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Ophthalmology – Epiphora
Epiphora, commonly referred to as excessive tearing, results from an imbalance between tear production and tear drainage. Tears are produced by the lacrimal glands and normally drain through the nasolacrimal system into the nose. Any disruption in this balance—either overproduction due to irritation or impaired drainage due to obstruction—can lead to tearing.
Epidemiologically, epiphora shows a bimodal distribution, occurring most often in infants and older adults. In infants, the most common cause is congenital nasolacrimal duct obstruction, affecting about 5% of newborns, with 90% resolving spontaneously by age 1. In adults, tearing is frequently due to dry eye syndrome, particularly in postmenopausal women, where ocular surface irritation leads to reflex tearing.
The pathophysiology involves disruption of the normal tear film dynamics. Tears consist of aqueous, lipid, and mucin layers that maintain ocular surface health. Blinking helps pump tears into the drainage system. In infants, incomplete canalization of the nasolacrimal duct leads to obstruction. In adults, dry eye or tear film instability causes irritation and reflex tearing. Other contributors include blepharitis (affecting lipid layer), decreased tear production, eyelid malposition (e.g., ectropion), or obstruction from inflammation, trauma, or infection.
Etiologically, epiphora can be broadly divided into overproduction and outflow obstruction. Overproduction is usually secondary to ocular surface irritation, such as from trichiasis, entropion, keratitis, uveitis, conjunctivitis, or foreign bodies. Outflow obstruction may occur anywhere along the lacrimal drainage pathway due to infection (dacryocystitis), inflammation, trauma, or medication-induced stenosis. Poor tear pump function from eyelid laxity or facial nerve palsy may also contribute.
Clinically, infants present with constant tearing shortly after birth, often accompanied by crusting of eyelashes, especially after sleep, and symptoms may worsen with nasal congestion. Adults with dry eye typically report intermittent tearing, worsened by activities that reduce blinking (e.g., reading, screen use, driving) or environmental factors like wind and cold air. In contrast, patients with obstruction often have constant tearing and may have a history of infection or trauma.
Physical examination includes assessment of the tear film quality and quantity, eyelid position (looking for entropion, ectropion, or misdirected lashes), and ocular surface for signs of dry eye or inflammation. Evaluation of the lacrimal drainage system includes inspection of the puncta, canaliculi, and lacrimal sac, with palpation to check for reflux of discharge suggestive of obstruction or infection.
Diagnostic testing may include the fluorescein dye disappearance test, where persistence of dye suggests impaired drainage. Schirmer testing evaluates tear production, with less than 5 mm of wetting in 5 minutes indicating dry eye. Additional studies such as dacryocystography or lacrimal scintigraphy can help differentiate obstruction from pump failure. Imaging (CT scan) may be used if structural abnormalities, cysts, or tumors are suspected. Lacrimal irrigation in-office is a useful diagnostic tool in older children and adults.
The differential diagnosis varies by age. In children, causes include congenital nasolacrimal duct obstruction, congenital glaucoma, and epiblepharon. In adults, common causes include dry eye, nasolacrimal duct obstruction, eyelid malposition, trichiasis, and facial nerve palsy, while acute causes include conjunctivitis, keratitis, uveitis, or foreign body.
Management depends on the underlying cause. In infants, conservative treatment includes topical antibiotic ointment for discharge and lacrimal sac massage, which can help open the duct. Most cases resolve spontaneously. In adults with dry eye, artificial tears are first-line, with second-line options including topical cyclosporine or short-term steroids for inflammation. Acute causes require treatment of the underlying condition, such as antibiotics for infection or removal of a foreign body.
Procedural interventions include punctal occlusion for dry eye, punctoplasty for stenosis, and probing and irrigation for congenital obstruction. Surgical options such as dacryocystorhinostomy (DCR) are used for persistent nasolacrimal duct obstruction. Eyelid malpositions may require entropion or ectropion repair.
Follow-up varies by age and severity. Infants are typically observed during the first year, with surgery considered if symptoms persist beyond age 1. Adults are managed based on cause, with surgical follow-up as needed. Prognosis is excellent in pediatric cases, while in adults it depends on the underlying etiology—patients with obstruction often do well after surgery, whereas those with chronic dry eye may have ongoing intermittent symptoms.
Epiphora, commonly referred to as excessive tearing, results from an imbalance between tear production and tear drainage. Tears are produced by the lacrimal glands and normally drain through the nasolacrimal system into the nose. Any disruption in this balance—either overproduction due to irritation or impaired drainage due to obstruction—can lead to tearing.
Epidemiologically, epiphora shows a bimodal distribution, occurring most often in infants and older adults. In infants, the most common cause is congenital nasolacrimal duct obstruction, affecting about 5% of newborns, with 90% resolving spontaneously by age 1. In adults, tearing is frequently due to dry eye syndrome, particularly in postmenopausal women, where ocular surface irritation leads to reflex tearing.
The pathophysiology involves disruption of the normal tear film dynamics. Tears consist of aqueous, lipid, and mucin layers that maintain ocular surface health. Blinking helps pump tears into the drainage system. In infants, incomplete canalization of the nasolacrimal duct leads to obstruction. In adults, dry eye or tear film instability causes irritation and reflex tearing. Other contributors include blepharitis (affecting lipid layer), decreased tear production, eyelid malposition (e.g., ectropion), or obstruction from inflammation, trauma, or infection.
Etiologically, epiphora can be broadly divided into overproduction and outflow obstruction. Overproduction is usually secondary to ocular surface irritation, such as from trichiasis, entropion, keratitis, uveitis, conjunctivitis, or foreign bodies. Outflow obstruction may occur anywhere along the lacrimal drainage pathway due to infection (dacryocystitis), inflammation, trauma, or medication-induced stenosis. Poor tear pump function from eyelid laxity or facial nerve palsy may also contribute.
Clinically, infants present with constant tearing shortly after birth, often accompanied by crusting of eyelashes, especially after sleep, and symptoms may worsen with nasal congestion. Adults with dry eye typically report intermittent tearing, worsened by activities that reduce blinking (e.g., reading, screen use, driving) or environmental factors like wind and cold air. In contrast, patients with obstruction often have constant tearing and may have a history of infection or trauma.
Physical examination includes assessment of the tear film quality and quantity, eyelid position (looking for entropion, ectropion, or misdirected lashes), and ocular surface for signs of dry eye or inflammation. Evaluation of the lacrimal drainage system includes inspection of the puncta, canaliculi, and lacrimal sac, with palpation to check for reflux of discharge suggestive of obstruction or infection.
Diagnostic testing may include the fluorescein dye disappearance test, where persistence of dye suggests impaired drainage. Schirmer testing evaluates tear production, with less than 5 mm of wetting in 5 minutes indicating dry eye. Additional studies such as dacryocystography or lacrimal scintigraphy can help differentiate obstruction from pump failure. Imaging (CT scan) may be used if structural abnormalities, cysts, or tumors are suspected. Lacrimal irrigation in-office is a useful diagnostic tool in older children and adults.
The differential diagnosis varies by age. In children, causes include congenital nasolacrimal duct obstruction, congenital glaucoma, and epiblepharon. In adults, common causes include dry eye, nasolacrimal duct obstruction, eyelid malposition, trichiasis, and facial nerve palsy, while acute causes include conjunctivitis, keratitis, uveitis, or foreign body.
Management depends on the underlying cause. In infants, conservative treatment includes topical antibiotic ointment for discharge and lacrimal sac massage, which can help open the duct. Most cases resolve spontaneously. In adults with dry eye, artificial tears are first-line, with second-line options including topical cyclosporine or short-term steroids for inflammation. Acute causes require treatment of the underlying condition, such as antibiotics for infection or removal of a foreign body.
Procedural interventions include punctal occlusion for dry eye, punctoplasty for stenosis, and probing and irrigation for congenital obstruction. Surgical options such as dacryocystorhinostomy (DCR) are used for persistent nasolacrimal duct obstruction. Eyelid malpositions may require entropion or ectropion repair.
Follow-up varies by age and severity. Infants are typically observed during the first year, with surgery considered if symptoms persist beyond age 1. Adults are managed based on cause, with surgical follow-up as needed. Prognosis is excellent in pediatric cases, while in adults it depends on the underlying etiology—patients with obstruction often do well after surgery, whereas those with chronic dry eye may have ongoing intermittent symptoms.
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Ophthalmology – Episcleritis
Episcleritis is a benign, self-limited inflammatory condition affecting the episclera, the thin vascular layer just beneath the conjunctiva. It is typically mild, though it may be recurrent, and most commonly affects young adults, with a higher prevalence in females. Up to 30% of cases are associated with an underlying systemic condition.
There are two main clinical forms. Simple episcleritis presents with intermittent episodes of redness that resolve within 2–3 weeks. Nodular episcleritis is less common but tends to be more painful, prolonged, and characterized by a localized, raised inflammatory nodule. This form is more frequently associated with systemic disease.
The exact pathophysiology is not fully understood but is believed to involve a localized inflammatory response to an inciting trigger. The etiology is often idiopathic, though it may be associated with collagen vascular diseases (such as rheumatoid arthritis or lupus), infections (e.g., Lyme disease or syphilis), and other systemic conditions like gout or rosacea. Stress and hormonal changes have also been implicated.
Patients typically present with acute onset of redness, mild irritation, and tearing, often in a sectoral (localized) or diffuse pattern. Unlike more severe inflammatory conditions, pain is usually mild or absent, and vision is typically unaffected.
On examination, there is sectoral or diffuse conjunctival/episcleral injection, sometimes with a mobile, localized nodule. A key distinguishing feature is that the inflamed area can be moved over the sclera with a cotton-tipped applicator after topical anesthesia. Additionally, instillation of 2.5% phenylephrine drops causes blanching of the superficial vessels, helping differentiate episcleritis from deeper conditions like scleritis. About 10% of patients may have associated anterior uveitis, so a careful anterior segment exam is important.
Diagnosis is primarily clinical. Laboratory testing is not routinely required for isolated cases but should be considered in recurrent, severe, or nodular episcleritis, especially if systemic disease is suspected. Workup may include CBC, ESR, ANA, rheumatoid factor, uric acid levels, chest X-ray, and syphilis testing (VDRL, FTA-ABS).
The differential diagnosis includes conjunctivitis, scleritis (which is more painful and does not blanch with phenylephrine), and pingueculitis.
Management is usually conservative. First-line treatment includes artificial tears and cool compresses, which are often sufficient due to the self-limiting nature of the condition. For symptomatic relief, topical antihistamines or NSAIDs may be used. In more moderate cases, oral NSAIDs (e.g., indomethacin) or a short course of topical corticosteroids may be prescribed.
Follow-up is generally not required for isolated cases but is recommended for recurrent episodes or atypical presentations. Referral to an ophthalmologist is advised if there are corneal changes, persistent symptoms, or suspicion of underlying systemic disease.
The prognosis is excellent, with most cases resolving without complications. However, recurrence is common, and identifying any associated systemic condition is important for long-term management.
Episcleritis is a benign, self-limited inflammatory condition affecting the episclera, the thin vascular layer just beneath the conjunctiva. It is typically mild, though it may be recurrent, and most commonly affects young adults, with a higher prevalence in females. Up to 30% of cases are associated with an underlying systemic condition.
There are two main clinical forms. Simple episcleritis presents with intermittent episodes of redness that resolve within 2–3 weeks. Nodular episcleritis is less common but tends to be more painful, prolonged, and characterized by a localized, raised inflammatory nodule. This form is more frequently associated with systemic disease.
The exact pathophysiology is not fully understood but is believed to involve a localized inflammatory response to an inciting trigger. The etiology is often idiopathic, though it may be associated with collagen vascular diseases (such as rheumatoid arthritis or lupus), infections (e.g., Lyme disease or syphilis), and other systemic conditions like gout or rosacea. Stress and hormonal changes have also been implicated.
Patients typically present with acute onset of redness, mild irritation, and tearing, often in a sectoral (localized) or diffuse pattern. Unlike more severe inflammatory conditions, pain is usually mild or absent, and vision is typically unaffected.
On examination, there is sectoral or diffuse conjunctival/episcleral injection, sometimes with a mobile, localized nodule. A key distinguishing feature is that the inflamed area can be moved over the sclera with a cotton-tipped applicator after topical anesthesia. Additionally, instillation of 2.5% phenylephrine drops causes blanching of the superficial vessels, helping differentiate episcleritis from deeper conditions like scleritis. About 10% of patients may have associated anterior uveitis, so a careful anterior segment exam is important.
Diagnosis is primarily clinical. Laboratory testing is not routinely required for isolated cases but should be considered in recurrent, severe, or nodular episcleritis, especially if systemic disease is suspected. Workup may include CBC, ESR, ANA, rheumatoid factor, uric acid levels, chest X-ray, and syphilis testing (VDRL, FTA-ABS).
The differential diagnosis includes conjunctivitis, scleritis (which is more painful and does not blanch with phenylephrine), and pingueculitis.
Management is usually conservative. First-line treatment includes artificial tears and cool compresses, which are often sufficient due to the self-limiting nature of the condition. For symptomatic relief, topical antihistamines or NSAIDs may be used. In more moderate cases, oral NSAIDs (e.g., indomethacin) or a short course of topical corticosteroids may be prescribed.
Follow-up is generally not required for isolated cases but is recommended for recurrent episodes or atypical presentations. Referral to an ophthalmologist is advised if there are corneal changes, persistent symptoms, or suspicion of underlying systemic disease.
The prognosis is excellent, with most cases resolving without complications. However, recurrence is common, and identifying any associated systemic condition is important for long-term management.
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Ophthalmology – Epiretinal Membranes (ERM)
Epiretinal membranes (ERM), also known as macular pucker, cellophane maculopathy, or surface wrinkling retinopathy, are thin fibrocellular layers that form on the inner surface of the retina, particularly over the macula. While many cases are mild and asymptomatic, ERMs can distort the retinal architecture, leading to blurred vision and metamorphopsia (distorted vision). They are commonly associated with posterior vitreous detachment (PVD) and may coexist with vitreomacular traction.
ERM is primarily a disease of the elderly population, with prevalence increasing significantly with age. It is found in about 2% of individuals at age 50, rising to 20% by age 75. Although bilateral in 20–30% of cases, it is often asymmetric. Risk factors include female gender, aging, prior ocular surgery or trauma, diabetes, retinal vascular disease, intraocular inflammation, and vitreous hemorrhage. Pediatric cases are rare and usually secondary to other ocular abnormalities.
The pathophysiology involves abnormal proliferation of glial cells (including Müller cells, astrocytes, fibrocytes, and myofibroblasts) on the retinal surface. These cells often migrate after a posterior vitreous detachment, although they may appear earlier. Over time, these cells can acquire contractile properties, exerting traction on the retina and leading to wrinkling, distortion, and reduced visual acuity.
ERM can be classified as idiopathic (primary) or secondary. Idiopathic ERMs occur without an identifiable cause, while secondary ERMs develop in association with retinal vascular diseases, inflammation, trauma, or prior surgery.
Clinically, many patients are asymptomatic, especially in early stages. Symptomatic patients may report gradual vision loss, distortion of straight lines (metamorphopsia), difficulty reading, or central blurring. Occasionally, patients may experience diplopia or photopsias.
On examination, subtle ERMs may appear as a shiny, glistening reflex on the macula, while more advanced cases show retinal folds (striae), vessel tortuosity, and macular thickening. In some cases, cystoid macular edema (CME) or small hemorrhages may be present due to traction.
Diagnosis is primarily clinical but is best confirmed with imaging. Optical coherence tomography (OCT) is the gold standard and demonstrates retinal surface wrinkling, thickening, and possible cystoid changes. OCT also helps assess prognosis, as disruption of photoreceptor layers or significant edema correlates with poorer outcomes. Fluorescein angiography (FA) may be used to evaluate for underlying vascular disease or macular leakage. Amsler grid testing is useful for monitoring visual distortion.
The differential diagnosis includes proliferative diabetic retinopathy, retinal vein occlusion-related fibrosis, and incomplete posterior vitreous detachment with adherent posterior hyaloid.
Management depends on symptom severity. Asymptomatic patients require no treatment and can be observed with periodic follow-up. For patients with mild edema, topical NSAIDs or steroids may be used. However, medical therapy is generally limited in effectiveness for ERM itself.
Definitive treatment is surgical, indicated in patients with significant visual symptoms or visual acuity worse than ~20/40. The procedure involves pars plana vitrectomy with membrane peeling, often including removal of the internal limiting membrane (ILM) to reduce recurrence risk. Advances in minimally invasive vitrectomy have improved recovery times and outcomes.
Follow-up includes routine monitoring and Amsler grid use, with prompt reassessment if symptoms worsen. Many ERMs remain stable for years, but progression can occur, especially after acute PVD or ocular surgery.
The prognosis is generally favorable. Asymptomatic patients maintain good vision, while 80–90% of surgical patients experience improvement of at least two Snellen lines. However, complete restoration to normal vision (20/20) is uncommon, and outcomes depend largely on preoperative visual acuity and retinal integrity.
Complications include cataract formation (most common), retinal tears or detachment, recurrent ERM, retinal phototoxicity, and rarely endophthalmitis.
Epiretinal membranes (ERM), also known as macular pucker, cellophane maculopathy, or surface wrinkling retinopathy, are thin fibrocellular layers that form on the inner surface of the retina, particularly over the macula. While many cases are mild and asymptomatic, ERMs can distort the retinal architecture, leading to blurred vision and metamorphopsia (distorted vision). They are commonly associated with posterior vitreous detachment (PVD) and may coexist with vitreomacular traction.
ERM is primarily a disease of the elderly population, with prevalence increasing significantly with age. It is found in about 2% of individuals at age 50, rising to 20% by age 75. Although bilateral in 20–30% of cases, it is often asymmetric. Risk factors include female gender, aging, prior ocular surgery or trauma, diabetes, retinal vascular disease, intraocular inflammation, and vitreous hemorrhage. Pediatric cases are rare and usually secondary to other ocular abnormalities.
The pathophysiology involves abnormal proliferation of glial cells (including Müller cells, astrocytes, fibrocytes, and myofibroblasts) on the retinal surface. These cells often migrate after a posterior vitreous detachment, although they may appear earlier. Over time, these cells can acquire contractile properties, exerting traction on the retina and leading to wrinkling, distortion, and reduced visual acuity.
ERM can be classified as idiopathic (primary) or secondary. Idiopathic ERMs occur without an identifiable cause, while secondary ERMs develop in association with retinal vascular diseases, inflammation, trauma, or prior surgery.
Clinically, many patients are asymptomatic, especially in early stages. Symptomatic patients may report gradual vision loss, distortion of straight lines (metamorphopsia), difficulty reading, or central blurring. Occasionally, patients may experience diplopia or photopsias.
On examination, subtle ERMs may appear as a shiny, glistening reflex on the macula, while more advanced cases show retinal folds (striae), vessel tortuosity, and macular thickening. In some cases, cystoid macular edema (CME) or small hemorrhages may be present due to traction.
Diagnosis is primarily clinical but is best confirmed with imaging. Optical coherence tomography (OCT) is the gold standard and demonstrates retinal surface wrinkling, thickening, and possible cystoid changes. OCT also helps assess prognosis, as disruption of photoreceptor layers or significant edema correlates with poorer outcomes. Fluorescein angiography (FA) may be used to evaluate for underlying vascular disease or macular leakage. Amsler grid testing is useful for monitoring visual distortion.
The differential diagnosis includes proliferative diabetic retinopathy, retinal vein occlusion-related fibrosis, and incomplete posterior vitreous detachment with adherent posterior hyaloid.
Management depends on symptom severity. Asymptomatic patients require no treatment and can be observed with periodic follow-up. For patients with mild edema, topical NSAIDs or steroids may be used. However, medical therapy is generally limited in effectiveness for ERM itself.
Definitive treatment is surgical, indicated in patients with significant visual symptoms or visual acuity worse than ~20/40. The procedure involves pars plana vitrectomy with membrane peeling, often including removal of the internal limiting membrane (ILM) to reduce recurrence risk. Advances in minimally invasive vitrectomy have improved recovery times and outcomes.
Follow-up includes routine monitoring and Amsler grid use, with prompt reassessment if symptoms worsen. Many ERMs remain stable for years, but progression can occur, especially after acute PVD or ocular surgery.
The prognosis is generally favorable. Asymptomatic patients maintain good vision, while 80–90% of surgical patients experience improvement of at least two Snellen lines. However, complete restoration to normal vision (20/20) is uncommon, and outcomes depend largely on preoperative visual acuity and retinal integrity.
Complications include cataract formation (most common), retinal tears or detachment, recurrent ERM, retinal phototoxicity, and rarely endophthalmitis.
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Toxicology – Drugs causing Hypotenssion
C – Clonidine:
A central-acting α₂ receptor agonist that can initially cause hypertension followed by hypotension.
C – Calcium Channel Blockers:
A class of antihypertensive and antianginal medications that decrease heart rate and dilate peripheral vasculature.
R – Reserpine:
A sympatholytic antihypertensive medication that blocks the reuptake of norepinephrine, dopamine, and serotonin, leading to enhanced degradation by MAO in the synaptic space.
A – Antidepressants:
Tricyclic antidepressants (TCAs) can induce hypotension through α₁ receptor blockade and by causing cardiac dysrhythmias and subsequent cardiac collapse.
A – Aminophylline:
A methylxanthine that acts as an adenosine receptor antagonist, β-blocker, and phosphodiesterase inhibitor that can cause hypotension and cardiac collapse in overdose settings.
S – Sedative–Hypnotics:
Hypotension can occur secondary to myocardial depression.
H – Heroin:
Opiates can induce hypotension secondary to histamine release, direct vasodilation, or through a centrally mediated decrease of vagal tone.
Treatment:
Hypotension is best treated with large fluid boluses followed by the administration of antidotes and/or treatment of the respective toxin. Pressors may be indicated if the patient remains hypotensive after fluid resuscitation.
C – Clonidine:
A central-acting α₂ receptor agonist that can initially cause hypertension followed by hypotension.
C – Calcium Channel Blockers:
A class of antihypertensive and antianginal medications that decrease heart rate and dilate peripheral vasculature.
R – Reserpine:
A sympatholytic antihypertensive medication that blocks the reuptake of norepinephrine, dopamine, and serotonin, leading to enhanced degradation by MAO in the synaptic space.
A – Antidepressants:
Tricyclic antidepressants (TCAs) can induce hypotension through α₁ receptor blockade and by causing cardiac dysrhythmias and subsequent cardiac collapse.
A – Aminophylline:
A methylxanthine that acts as an adenosine receptor antagonist, β-blocker, and phosphodiesterase inhibitor that can cause hypotension and cardiac collapse in overdose settings.
S – Sedative–Hypnotics:
Hypotension can occur secondary to myocardial depression.
H – Heroin:
Opiates can induce hypotension secondary to histamine release, direct vasodilation, or through a centrally mediated decrease of vagal tone.
Treatment:
Hypotension is best treated with large fluid boluses followed by the administration of antidotes and/or treatment of the respective toxin. Pressors may be indicated if the patient remains hypotensive after fluid resuscitation.
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Toxicology – APPROACH TO THE POISONED PATIENT
ABC’s:
As with all emergency department patients, first ensure the patient has a patent airway, is breathing, and has a pulse. Immediate intervention is required if any or all of these are absent.
Vital Signs:
Temperature, heart rate, blood pressure, respiratory rate, and O₂ saturation will help guide the diagnosis and help categorize the intoxication or overdose into one of the more common toxidromes.
History:
Attempt to get a good history using collateral sources if possible, as the poisoned patient is often unreliable or containers altered. EMS, family members, occupation, past medical records, and empty pill bottles can provide insight into the potential toxin or overdose.
Physical:
In addition to vital signs, physical examination will help tease out the clinical toxidrome.
PEARLS
ABC’s:
As with all emergency department patients, first ensure the patient has a patent airway, is breathing, and has a pulse. Immediate intervention is required if any or all of these are absent.
Vital Signs:
Temperature, heart rate, blood pressure, respiratory rate, and O₂ saturation will help guide the diagnosis and help categorize the intoxication or overdose into one of the more common toxidromes.
History:
Attempt to get a good history using collateral sources if possible, as the poisoned patient is often unreliable or containers altered. EMS, family members, occupation, past medical records, and empty pill bottles can provide insight into the potential toxin or overdose.
- What: Consider what medications the patient has access to including his or her own, as well as those of parents, friends, significant others, children and visiting relatives. Ask if the drug is an immediate-release or sustained-release product.
- When: A time frame of suspected ingestion can influence treatment options and patient disposition. For example, some toxins have a delayed onset and some antidotes must be given within a specific time frame.
- Dose: Assume that any unreliable patient took the highest possible dose. Count the number of pills remaining in their prescription bottles and subtract that amount from the initial number prescribed. Assume all missing pills were taken as a single overdose.
- Why: Was this an accidental ingestion, a therapeutic misadventure in pursuit of a “high” or in pursuit of better treatment outcomes, or was it a suicide attempt? The answer will help determine the patient’s disposition.
- Coingestions: Multiple drug ingestions are common; alcohol is the most common coingestion.
Physical:
In addition to vital signs, physical examination will help tease out the clinical toxidrome.
- Mental Status: Agitation / somnolence / paranoid / obtunded / comatose
- Skin: Wet / dry / cyanotic / erythematous / pale / hot / cold
- Eyes: Miosis / mydriasis / nystagmus / conjunctival injection / jaundice
- Mucous Membranes: Wet and salivating / dry and chapped
- Heart/EKG: Tachycardia / bradycardia / QRS widened / QT prolongation
- Lungs: Tachypnea / bradypnea / rales / wheezing / crackles
- Bowel Sounds: Hyperactive / normal / absent
- Neurological: Hyperreflexia / hyporeflexia
PEARLS
- US Poison Control Center: 1-800-222-1222
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Ophthalmology – Esotropia (Comitant)
Comitant esotropia is a form of strabismus in which one eye deviates inward toward the nose, with the key feature that the angle of deviation remains the same in all directions of gaze. It may be intermittent or constant and includes several subtypes such as accommodative, nonaccommodative, sensory, congenital/infantile, consecutive (after exotropia surgery), and cyclic esotropia. Rarely, it may be associated with systemic conditions such as ocular myasthenia gravis or thyroid eye disease.
This condition is relatively common in childhood, with an incidence of about 111 per 100,000 children under 19 years and a prevalence of approximately 2% in children under 6 years. Risk factors include hyperopia (farsightedness), poor vision in one or both eyes (sensory esotropia), prematurity, cerebral palsy, seizure disorders, and developmental delay. There is also a multifactorial genetic component, particularly in accommodative esotropia, where a strong family history is often present.
The pathophysiology depends on the subtype. In accommodative esotropia, excessive focusing effort to overcome hyperopia leads to increased convergence, resulting in inward deviation. In other forms, no clear abnormality in muscles or nerves is identified. Acute onset esotropia may raise concern for intracranial pathology such as tumors, Chiari malformation, or hydrocephalus.
Etiologically, accommodative esotropia is strongly linked to uncorrected hyperopia. Sensory esotropia arises when poor vision disrupts binocular alignment, often due to conditions like cataract or retinal disease. Acute comitant esotropia may indicate neurologic disease, and should prompt further evaluation.
Clinically, esotropia is often first noticed by parents in children, sometimes beginning intermittently and progressing to constant deviation. Symptoms may include crossed eyes, diplopia (in acute cases), or decreased vision. A history of neurologic issues, developmental delay, or prematurity may also be present.
On examination, a complete ophthalmic evaluation is essential. This includes cycloplegic refraction (often requiring atropine), assessment of ocular alignment in all gaze positions, and testing of stereoacuity. The AC/A ratio (accommodative convergence to accommodation) is particularly important in evaluating accommodative esotropia. Visual acuity testing is crucial to identify amblyopia, a common associated condition.
Diagnostic testing is usually not required unless atypical features are present. In suspected cases of myasthenia gravis, antibody testing or a Tensilon test may be performed. If thyroid eye disease is suspected, thyroid function tests are indicated. Neuroimaging (MRI of brain and orbits) is reserved for cases with acute onset or associated neurologic signs.
The differential diagnosis includes pseudoesotropia (common in infants with prominent epicanthal folds), incomitant esotropia, and systemic conditions like myasthenia gravis or thyroid eye disease.
Management depends on the cause. First-line treatment for accommodative esotropia is full correction of hyperopia with glasses or contact lenses, which often restores alignment. In cases with high AC/A ratio, bifocals may be required. Treatment of amblyopia with patching or atropine drops is critical.
Medications are generally not used, except in specific conditions such as myasthenia gravis. Vision therapy has no proven role in treatment.
Surgical intervention is indicated when alignment cannot be adequately controlled with optical correction. Procedures typically involve recession or resection of extraocular muscles, most commonly bilateral medial rectus recession. Surgery is usually performed on an outpatient basis.
Follow-up is essential, especially in children. Stable accommodative esotropia is typically monitored every 3–4 months, while more variable cases require closer observation. Parents should monitor eye alignment, and patients should report frequency of diplopia if present.
The prognosis varies by subtype. In accommodative esotropia, approximately one-third require lifelong glasses, one-third outgrow the need, and one-third eventually need surgery. Outcomes depend on early detection and treatment, particularly for preventing amblyopia. Acute cases depend on the underlying cause.
Complications include amblyopia and potential over- or undercorrection after surgery. Rare surgical risks include infection, hemorrhage, or muscle complications, though overall outcomes are generally favorable with appropriate management.
Comitant esotropia is a form of strabismus in which one eye deviates inward toward the nose, with the key feature that the angle of deviation remains the same in all directions of gaze. It may be intermittent or constant and includes several subtypes such as accommodative, nonaccommodative, sensory, congenital/infantile, consecutive (after exotropia surgery), and cyclic esotropia. Rarely, it may be associated with systemic conditions such as ocular myasthenia gravis or thyroid eye disease.
This condition is relatively common in childhood, with an incidence of about 111 per 100,000 children under 19 years and a prevalence of approximately 2% in children under 6 years. Risk factors include hyperopia (farsightedness), poor vision in one or both eyes (sensory esotropia), prematurity, cerebral palsy, seizure disorders, and developmental delay. There is also a multifactorial genetic component, particularly in accommodative esotropia, where a strong family history is often present.
The pathophysiology depends on the subtype. In accommodative esotropia, excessive focusing effort to overcome hyperopia leads to increased convergence, resulting in inward deviation. In other forms, no clear abnormality in muscles or nerves is identified. Acute onset esotropia may raise concern for intracranial pathology such as tumors, Chiari malformation, or hydrocephalus.
Etiologically, accommodative esotropia is strongly linked to uncorrected hyperopia. Sensory esotropia arises when poor vision disrupts binocular alignment, often due to conditions like cataract or retinal disease. Acute comitant esotropia may indicate neurologic disease, and should prompt further evaluation.
Clinically, esotropia is often first noticed by parents in children, sometimes beginning intermittently and progressing to constant deviation. Symptoms may include crossed eyes, diplopia (in acute cases), or decreased vision. A history of neurologic issues, developmental delay, or prematurity may also be present.
On examination, a complete ophthalmic evaluation is essential. This includes cycloplegic refraction (often requiring atropine), assessment of ocular alignment in all gaze positions, and testing of stereoacuity. The AC/A ratio (accommodative convergence to accommodation) is particularly important in evaluating accommodative esotropia. Visual acuity testing is crucial to identify amblyopia, a common associated condition.
Diagnostic testing is usually not required unless atypical features are present. In suspected cases of myasthenia gravis, antibody testing or a Tensilon test may be performed. If thyroid eye disease is suspected, thyroid function tests are indicated. Neuroimaging (MRI of brain and orbits) is reserved for cases with acute onset or associated neurologic signs.
The differential diagnosis includes pseudoesotropia (common in infants with prominent epicanthal folds), incomitant esotropia, and systemic conditions like myasthenia gravis or thyroid eye disease.
Management depends on the cause. First-line treatment for accommodative esotropia is full correction of hyperopia with glasses or contact lenses, which often restores alignment. In cases with high AC/A ratio, bifocals may be required. Treatment of amblyopia with patching or atropine drops is critical.
Medications are generally not used, except in specific conditions such as myasthenia gravis. Vision therapy has no proven role in treatment.
Surgical intervention is indicated when alignment cannot be adequately controlled with optical correction. Procedures typically involve recession or resection of extraocular muscles, most commonly bilateral medial rectus recession. Surgery is usually performed on an outpatient basis.
Follow-up is essential, especially in children. Stable accommodative esotropia is typically monitored every 3–4 months, while more variable cases require closer observation. Parents should monitor eye alignment, and patients should report frequency of diplopia if present.
The prognosis varies by subtype. In accommodative esotropia, approximately one-third require lifelong glasses, one-third outgrow the need, and one-third eventually need surgery. Outcomes depend on early detection and treatment, particularly for preventing amblyopia. Acute cases depend on the underlying cause.
Complications include amblyopia and potential over- or undercorrection after surgery. Rare surgical risks include infection, hemorrhage, or muscle complications, though overall outcomes are generally favorable with appropriate management.
- Published on
Surgery - Surgical Terms
Allen’s Test
Allen’s test is used to assess the adequacy of blood flow to the hand via the radial and ulnar arteries. The patient is asked to clench their fist to expel blood while both arteries are compressed. After opening the blanched hand, one artery is released to observe if normal color returns, indicating patency. The process is then repeated for the other artery.
Argyll Robertson Pupil
Argyll Robertson pupil is characterized by pupils that constrict during accommodation (focusing on near objects) but do not respond to light. This dissociation is remembered by the mnemonic: Accommodation Reflex Present, Pupillary Response Absent.
Barton’s Fracture
Barton’s fracture is a fracture-dislocation of the distal radius involving the articular surface, typically affecting the volar lip. The distal fragment and hand are displaced proximally and volarly, and it can sometimes be mistaken for a Colles’ fracture.
Battle’s Sign
Battle’s sign refers to bruising over the mastoid region (behind the ear) and is a clinical indicator of a basal skull fracture.
Beck’s Triad
Beck’s triad is a set of three clinical signs seen in cardiac tamponade: raised jugular venous pressure, muffled heart sounds, and hypotension.
Bell’s Palsy
Bell’s palsy is an acute lower motor neuron facial nerve paralysis of unknown cause. It presents with unilateral facial weakness and is diagnosed after excluding other causes.
Chvostek’s Sign
Chvostek’s sign is a clinical sign of hypocalcaemia. Tapping over the facial nerve triggers twitching of the facial muscles.
Colles’ Fracture
Colles’ fracture is a fracture of the distal radius, typically within 2 cm of the wrist joint, with dorsal displacement of the distal fragment, producing a characteristic “dinner fork” deformity.
Compartment Syndrome
Compartment syndrome occurs when pressure within a closed anatomical space rises to a level that compromises circulation and tissue viability, potentially leading to permanent damage if untreated.
Cushing’s Triad
Cushing’s triad is associated with raised intracranial pressure and consists of hypertension, bradycardia, and irregular respirations.
De Quervain’s Tenosynovitis
De Quervain’s tenosynovitis is inflammation of the extensor pollicis brevis and abductor pollicis longus tendons due to repetitive use, causing pain on thumb movement.
Finkelstein’s Test
Finkelstein’s test is used to diagnose De Quervain’s tenosynovitis. The patient makes a fist with the thumb inside, and ulnar deviation of the wrist causes pain due to tendon stretching.
Frey’s Syndrome
Frey’s syndrome is characterized by sweating and flushing over the cheek when eating or thinking about food. It occurs due to misdirected regeneration of autonomic fibers after parotid gland injury.
Galeazzi Fracture
Galeazzi fracture involves a fracture of the radial shaft with dislocation of the distal radioulnar joint, disrupting the forearm axis.
Gradenigo’s Syndrome
Gradenigo’s syndrome is associated with complications of otitis media and includes ear infection signs, ipsilateral abducens nerve palsy, and trigeminal nerve pain.
Hitselberger’s Sign
Hitselberger’s sign involves increased sensitivity of the posterior external auditory canal along with hearing loss, often seen in acoustic neuroma.
Horner’s Syndrome
Horner’s syndrome results from disruption of sympathetic innervation to the eye, causing ptosis, miosis, anhidrosis, and enophthalmos on the affected side.
Monteggia Fracture
Monteggia fracture consists of a fracture of the proximal ulna with dislocation of the radial head.
Osler–Rendu–Weber Syndrome
Osler–Rendu–Weber syndrome, or hereditary haemorrhagic telangiectasia, causes abnormal blood vessel formation leading to frequent nosebleeds and mucosal telangiectasia.
Pendred’s Syndrome
Pendred’s syndrome is an autosomal recessive condition characterized by congenital sensorineural hearing loss and the development of a thyroid goitre.
Pierre Robin Sequence
Pierre Robin sequence includes a small mandible, cleft palate, and displacement of the tongue, often causing airway obstruction and feeding difficulties.
Raccoon Eyes
Raccoon eyes refer to bilateral periorbital bruising, commonly seen in basal skull fractures.
Refsum Disease
Refsum disease is a metabolic disorder presenting with retinitis pigmentosa, cerebellar ataxia, peripheral neuropathy, and hearing loss.
Ramsay Hunt Syndrome
Ramsay Hunt syndrome is caused by herpes zoster infection of the facial nerve and presents with facial paralysis and painful vesicles in the ear.
Smith’s Fracture
Smith’s fracture is a distal radius fracture with volar displacement of the distal fragment, usually resulting from a fall onto a flexed wrist.
Superior Vena Cava Syndrome
Superior vena cava syndrome occurs when there is obstruction of the SVC, leading to swelling and venous congestion of the face, neck, and upper chest.
Thoracic Outlet Syndrome
Thoracic outlet syndrome involves compression of nerves or blood vessels at the thoracic outlet, leading to upper limb symptoms.
Thornwaldt’s Cyst
Thornwaldt’s cyst is a benign cyst in the nasopharynx arising from the pharyngeal bursa and may cause nasal obstruction.
Treacher Collins Syndrome
Treacher Collins syndrome is a genetic disorder causing underdevelopment of facial bones, particularly the jaw and ears, often with hearing impairment.
Trousseau’s Sign
Trousseau’s sign is seen in hypocalcaemia, where inflation of a blood pressure cuff induces carpopedal spasm.
Waardenburg Syndrome
Waardenburg syndrome is a genetic condition characterized by wide-set eyes, pigment abnormalities such as a white forelock, and sensorineural hearing loss.
If you want, I can convert this into exam flashcards, OSCE notes, or ultra-short one-liners for quick recall.
Allen’s Test
Allen’s test is used to assess the adequacy of blood flow to the hand via the radial and ulnar arteries. The patient is asked to clench their fist to expel blood while both arteries are compressed. After opening the blanched hand, one artery is released to observe if normal color returns, indicating patency. The process is then repeated for the other artery.
Argyll Robertson Pupil
Argyll Robertson pupil is characterized by pupils that constrict during accommodation (focusing on near objects) but do not respond to light. This dissociation is remembered by the mnemonic: Accommodation Reflex Present, Pupillary Response Absent.
Barton’s Fracture
Barton’s fracture is a fracture-dislocation of the distal radius involving the articular surface, typically affecting the volar lip. The distal fragment and hand are displaced proximally and volarly, and it can sometimes be mistaken for a Colles’ fracture.
Battle’s Sign
Battle’s sign refers to bruising over the mastoid region (behind the ear) and is a clinical indicator of a basal skull fracture.
Beck’s Triad
Beck’s triad is a set of three clinical signs seen in cardiac tamponade: raised jugular venous pressure, muffled heart sounds, and hypotension.
Bell’s Palsy
Bell’s palsy is an acute lower motor neuron facial nerve paralysis of unknown cause. It presents with unilateral facial weakness and is diagnosed after excluding other causes.
Chvostek’s Sign
Chvostek’s sign is a clinical sign of hypocalcaemia. Tapping over the facial nerve triggers twitching of the facial muscles.
Colles’ Fracture
Colles’ fracture is a fracture of the distal radius, typically within 2 cm of the wrist joint, with dorsal displacement of the distal fragment, producing a characteristic “dinner fork” deformity.
Compartment Syndrome
Compartment syndrome occurs when pressure within a closed anatomical space rises to a level that compromises circulation and tissue viability, potentially leading to permanent damage if untreated.
Cushing’s Triad
Cushing’s triad is associated with raised intracranial pressure and consists of hypertension, bradycardia, and irregular respirations.
De Quervain’s Tenosynovitis
De Quervain’s tenosynovitis is inflammation of the extensor pollicis brevis and abductor pollicis longus tendons due to repetitive use, causing pain on thumb movement.
Finkelstein’s Test
Finkelstein’s test is used to diagnose De Quervain’s tenosynovitis. The patient makes a fist with the thumb inside, and ulnar deviation of the wrist causes pain due to tendon stretching.
Frey’s Syndrome
Frey’s syndrome is characterized by sweating and flushing over the cheek when eating or thinking about food. It occurs due to misdirected regeneration of autonomic fibers after parotid gland injury.
Galeazzi Fracture
Galeazzi fracture involves a fracture of the radial shaft with dislocation of the distal radioulnar joint, disrupting the forearm axis.
Gradenigo’s Syndrome
Gradenigo’s syndrome is associated with complications of otitis media and includes ear infection signs, ipsilateral abducens nerve palsy, and trigeminal nerve pain.
Hitselberger’s Sign
Hitselberger’s sign involves increased sensitivity of the posterior external auditory canal along with hearing loss, often seen in acoustic neuroma.
Horner’s Syndrome
Horner’s syndrome results from disruption of sympathetic innervation to the eye, causing ptosis, miosis, anhidrosis, and enophthalmos on the affected side.
Monteggia Fracture
Monteggia fracture consists of a fracture of the proximal ulna with dislocation of the radial head.
Osler–Rendu–Weber Syndrome
Osler–Rendu–Weber syndrome, or hereditary haemorrhagic telangiectasia, causes abnormal blood vessel formation leading to frequent nosebleeds and mucosal telangiectasia.
Pendred’s Syndrome
Pendred’s syndrome is an autosomal recessive condition characterized by congenital sensorineural hearing loss and the development of a thyroid goitre.
Pierre Robin Sequence
Pierre Robin sequence includes a small mandible, cleft palate, and displacement of the tongue, often causing airway obstruction and feeding difficulties.
Raccoon Eyes
Raccoon eyes refer to bilateral periorbital bruising, commonly seen in basal skull fractures.
Refsum Disease
Refsum disease is a metabolic disorder presenting with retinitis pigmentosa, cerebellar ataxia, peripheral neuropathy, and hearing loss.
Ramsay Hunt Syndrome
Ramsay Hunt syndrome is caused by herpes zoster infection of the facial nerve and presents with facial paralysis and painful vesicles in the ear.
Smith’s Fracture
Smith’s fracture is a distal radius fracture with volar displacement of the distal fragment, usually resulting from a fall onto a flexed wrist.
Superior Vena Cava Syndrome
Superior vena cava syndrome occurs when there is obstruction of the SVC, leading to swelling and venous congestion of the face, neck, and upper chest.
Thoracic Outlet Syndrome
Thoracic outlet syndrome involves compression of nerves or blood vessels at the thoracic outlet, leading to upper limb symptoms.
Thornwaldt’s Cyst
Thornwaldt’s cyst is a benign cyst in the nasopharynx arising from the pharyngeal bursa and may cause nasal obstruction.
Treacher Collins Syndrome
Treacher Collins syndrome is a genetic disorder causing underdevelopment of facial bones, particularly the jaw and ears, often with hearing impairment.
Trousseau’s Sign
Trousseau’s sign is seen in hypocalcaemia, where inflation of a blood pressure cuff induces carpopedal spasm.
Waardenburg Syndrome
Waardenburg syndrome is a genetic condition characterized by wide-set eyes, pigment abnormalities such as a white forelock, and sensorineural hearing loss.
If you want, I can convert this into exam flashcards, OSCE notes, or ultra-short one-liners for quick recall.
- Published on
1. Infectious Disease and Microbiology - Malaria
Malaria is a vector-borne parasitic disease transmitted by the bite of an infected female Anopheles mosquito. It is caused by protozoa of the genus Plasmodium and remains one of the most significant global infectious diseases, particularly affecting tropical and subtropical regions. The infection begins when sporozoites are introduced into the bloodstream, subsequently invading liver cells and later red blood cells, leading to systemic illness.
Malaria has a massive global burden, with hundreds of millions of cases annually and millions of deaths, most of which occur in children. It affects over 40% of the world’s population across more than 100 countries. Different species have distinct geographic distributions: Plasmodium falciparum predominates in Africa and is responsible for the most severe disease, while P. vivax, P. ovale, and P. malariae are distributed across other regions. Risk factors include travel to endemic areas, lack of immunity, and, rarely, transmission through blood transfusion or from mother to fetus. Certain genetic traits, such as sickle cell trait, offer partial protection against severe disease.
The pathophysiology involves a complex life cycle between the mosquito and human host. After liver-stage development, parasites invade red blood cells, multiply, and cause their destruction. This leads to hemolysis, release of inflammatory cytokines, and the characteristic febrile illness. P. falciparum is particularly dangerous due to its ability to cause cytoadherence, leading to sequestration of infected red blood cells in small blood vessels, resulting in impaired blood flow and organ dysfunction.
Clinically, malaria presents with nonspecific symptoms such as fever, malaise, headache, and myalgias. A hallmark feature is the malarial paroxysm, consisting of a cold stage with chills, a hot stage with high fever (often exceeding 40°C), and a sweating stage with resolution of fever and profound fatigue. Splenomegaly and tachycardia are common findings. Although fever patterns may be cyclic (tertian or quartan), this periodicity is not always reliable for diagnosis.
Diagnosis is primarily established by microscopic examination of thick and thin blood smears, which allows detection and identification of the parasite species. Rapid diagnostic tests detecting specific antigens are also widely used, especially in resource-limited settings. Laboratory findings often include anemia, thrombocytopenia, and markers of hemolysis. Molecular methods such as PCR can provide confirmation but are not routinely available.
Treatment depends on the species, severity, and drug resistance patterns. Uncomplicated malaria caused by chloroquine-sensitive strains can be treated with chloroquine, while resistant infections require agents such as atovaquone-proguanil, artemisinin-based combinations, or quinine-based regimens. Severe malaria, particularly due to P. falciparum, is a medical emergency requiring intravenous therapy such as artesunate or quinidine, along with intensive supportive care. Monitoring for complications such as hypoglycemia and renal failure is essential.
Preventive strategies focus on reducing mosquito exposure and chemoprophylaxis. Measures include insecticide-treated bed nets, protective clothing, and repellents such as DEET. Travelers to endemic regions may require prophylactic medications depending on resistance patterns. Individuals returning to endemic areas after prolonged absence are at increased risk due to loss of immunity.
The prognosis of malaria depends on early diagnosis and appropriate treatment. Uncomplicated malaria generally responds well to therapy, while untreated P. falciparum infection can lead to severe complications such as cerebral malaria, renal failure, metabolic acidosis, and death. Prompt recognition and management are critical to reducing morbidity and mortality.
Malaria is a vector-borne parasitic disease transmitted by the bite of an infected female Anopheles mosquito. It is caused by protozoa of the genus Plasmodium and remains one of the most significant global infectious diseases, particularly affecting tropical and subtropical regions. The infection begins when sporozoites are introduced into the bloodstream, subsequently invading liver cells and later red blood cells, leading to systemic illness.
Malaria has a massive global burden, with hundreds of millions of cases annually and millions of deaths, most of which occur in children. It affects over 40% of the world’s population across more than 100 countries. Different species have distinct geographic distributions: Plasmodium falciparum predominates in Africa and is responsible for the most severe disease, while P. vivax, P. ovale, and P. malariae are distributed across other regions. Risk factors include travel to endemic areas, lack of immunity, and, rarely, transmission through blood transfusion or from mother to fetus. Certain genetic traits, such as sickle cell trait, offer partial protection against severe disease.
The pathophysiology involves a complex life cycle between the mosquito and human host. After liver-stage development, parasites invade red blood cells, multiply, and cause their destruction. This leads to hemolysis, release of inflammatory cytokines, and the characteristic febrile illness. P. falciparum is particularly dangerous due to its ability to cause cytoadherence, leading to sequestration of infected red blood cells in small blood vessels, resulting in impaired blood flow and organ dysfunction.
Clinically, malaria presents with nonspecific symptoms such as fever, malaise, headache, and myalgias. A hallmark feature is the malarial paroxysm, consisting of a cold stage with chills, a hot stage with high fever (often exceeding 40°C), and a sweating stage with resolution of fever and profound fatigue. Splenomegaly and tachycardia are common findings. Although fever patterns may be cyclic (tertian or quartan), this periodicity is not always reliable for diagnosis.
Diagnosis is primarily established by microscopic examination of thick and thin blood smears, which allows detection and identification of the parasite species. Rapid diagnostic tests detecting specific antigens are also widely used, especially in resource-limited settings. Laboratory findings often include anemia, thrombocytopenia, and markers of hemolysis. Molecular methods such as PCR can provide confirmation but are not routinely available.
Treatment depends on the species, severity, and drug resistance patterns. Uncomplicated malaria caused by chloroquine-sensitive strains can be treated with chloroquine, while resistant infections require agents such as atovaquone-proguanil, artemisinin-based combinations, or quinine-based regimens. Severe malaria, particularly due to P. falciparum, is a medical emergency requiring intravenous therapy such as artesunate or quinidine, along with intensive supportive care. Monitoring for complications such as hypoglycemia and renal failure is essential.
Preventive strategies focus on reducing mosquito exposure and chemoprophylaxis. Measures include insecticide-treated bed nets, protective clothing, and repellents such as DEET. Travelers to endemic regions may require prophylactic medications depending on resistance patterns. Individuals returning to endemic areas after prolonged absence are at increased risk due to loss of immunity.
The prognosis of malaria depends on early diagnosis and appropriate treatment. Uncomplicated malaria generally responds well to therapy, while untreated P. falciparum infection can lead to severe complications such as cerebral malaria, renal failure, metabolic acidosis, and death. Prompt recognition and management are critical to reducing morbidity and mortality.
- Published on
Infectious Disease and Microbiology - Measles
Measles is a highly contagious viral disease characterized by fever and a distinctive maculopapular rash that begins on the face and spreads downward to the trunk and extremities. The rash is typically preceded by a prodromal phase of cough, coryza, and conjunctivitis, along with the pathognomonic Koplik’s spots on the buccal mucosa. While often self-limited in healthy children, measles remains a major cause of morbidity and mortality, particularly in malnourished or immunocompromised populations.
Globally, measles continues to affect millions of individuals each year, with significant mortality despite widespread vaccination efforts. Although vaccination coverage has improved, outbreaks still occur, especially in low-income countries and in areas affected by conflict or poor healthcare access. Individuals at highest risk include those who are unvaccinated, immunocompromised, pregnant, malnourished, or at extremes of age. Healthcare workers without immunity are also at risk and may contribute to transmission.
The virus spreads via respiratory droplets and initially infects the respiratory mucosa before disseminating through lymphatic and hematogenous routes. It affects multiple organ systems including the skin, conjunctiva, lungs, and gastrointestinal tract. The appearance of the rash corresponds with the host immune response and marks the decline in viral transmissibility. The causative agent is the measles (rubeola) virus, an RNA virus of the Paramyxoviridae family.
Clinically, measles begins with a prodrome of high fever, cough, conjunctivitis, and coryza. Koplik’s spots—small white lesions on the buccal mucosa—appear early and are highly characteristic. This is followed by a red maculopapular rash that starts behind the ears and on the forehead, then spreads downward. The rash typically lasts about five days before fading, sometimes followed by desquamation. In partially immune individuals, atypical and milder presentations may occur.
Diagnosis is primarily clinical, based on characteristic signs and symptoms. Laboratory findings may include leukopenia, T-cell cytopenia, and thrombocytopenia. Serologic testing can confirm diagnosis in atypical cases. Chest imaging may reveal interstitial pneumonitis in severe disease. Viral detection can be performed using immunofluorescence or PCR from respiratory secretions or urine, though this is not always necessary in typical cases.
There is no specific antiviral therapy for measles. Management is mainly supportive, focusing on hydration, fever control, and monitoring for complications. The World Health Organization recommends vitamin A supplementation in children, particularly in developing countries, as it reduces morbidity and mortality. Ribavirin may be considered in severe cases among immunocompromised patients. Antibiotics are reserved only for secondary bacterial infections. Post-exposure prophylaxis with immune serum globulin may prevent or attenuate disease in high-risk individuals.
Prevention is primarily achieved through vaccination with the measles-containing vaccine (commonly the MMR vaccine). The standard schedule includes an initial dose at 12–15 months and a booster at 4–6 years. Vaccination has dramatically reduced global incidence, and there is no evidence linking the vaccine to autism. Certain groups, such as pregnant women and severely immunocompromised individuals, should not receive the live vaccine.
The prognosis is generally excellent in healthy individuals, with lifelong immunity following recovery. However, complications are common in vulnerable populations and may include pneumonia, encephalitis, otitis media, severe diarrhea, and blindness. A rare but fatal long-term complication is subacute sclerosing panencephalitis (SSPE), which can occur years after the initial infection.
Measles is a highly contagious viral disease characterized by fever and a distinctive maculopapular rash that begins on the face and spreads downward to the trunk and extremities. The rash is typically preceded by a prodromal phase of cough, coryza, and conjunctivitis, along with the pathognomonic Koplik’s spots on the buccal mucosa. While often self-limited in healthy children, measles remains a major cause of morbidity and mortality, particularly in malnourished or immunocompromised populations.
Globally, measles continues to affect millions of individuals each year, with significant mortality despite widespread vaccination efforts. Although vaccination coverage has improved, outbreaks still occur, especially in low-income countries and in areas affected by conflict or poor healthcare access. Individuals at highest risk include those who are unvaccinated, immunocompromised, pregnant, malnourished, or at extremes of age. Healthcare workers without immunity are also at risk and may contribute to transmission.
The virus spreads via respiratory droplets and initially infects the respiratory mucosa before disseminating through lymphatic and hematogenous routes. It affects multiple organ systems including the skin, conjunctiva, lungs, and gastrointestinal tract. The appearance of the rash corresponds with the host immune response and marks the decline in viral transmissibility. The causative agent is the measles (rubeola) virus, an RNA virus of the Paramyxoviridae family.
Clinically, measles begins with a prodrome of high fever, cough, conjunctivitis, and coryza. Koplik’s spots—small white lesions on the buccal mucosa—appear early and are highly characteristic. This is followed by a red maculopapular rash that starts behind the ears and on the forehead, then spreads downward. The rash typically lasts about five days before fading, sometimes followed by desquamation. In partially immune individuals, atypical and milder presentations may occur.
Diagnosis is primarily clinical, based on characteristic signs and symptoms. Laboratory findings may include leukopenia, T-cell cytopenia, and thrombocytopenia. Serologic testing can confirm diagnosis in atypical cases. Chest imaging may reveal interstitial pneumonitis in severe disease. Viral detection can be performed using immunofluorescence or PCR from respiratory secretions or urine, though this is not always necessary in typical cases.
There is no specific antiviral therapy for measles. Management is mainly supportive, focusing on hydration, fever control, and monitoring for complications. The World Health Organization recommends vitamin A supplementation in children, particularly in developing countries, as it reduces morbidity and mortality. Ribavirin may be considered in severe cases among immunocompromised patients. Antibiotics are reserved only for secondary bacterial infections. Post-exposure prophylaxis with immune serum globulin may prevent or attenuate disease in high-risk individuals.
Prevention is primarily achieved through vaccination with the measles-containing vaccine (commonly the MMR vaccine). The standard schedule includes an initial dose at 12–15 months and a booster at 4–6 years. Vaccination has dramatically reduced global incidence, and there is no evidence linking the vaccine to autism. Certain groups, such as pregnant women and severely immunocompromised individuals, should not receive the live vaccine.
The prognosis is generally excellent in healthy individuals, with lifelong immunity following recovery. However, complications are common in vulnerable populations and may include pneumonia, encephalitis, otitis media, severe diarrhea, and blindness. A rare but fatal long-term complication is subacute sclerosing panencephalitis (SSPE), which can occur years after the initial infection.
- Published on
Infectious Disease and Microbiology - Mastoiditis
Mastoiditis is an infection and inflammation of the mastoid air cells of the temporal bone, typically classified as acute or chronic based on duration. Acute mastoiditis usually follows untreated or inadequately treated middle ear infection, whereas chronic mastoiditis is characterized by persistent ear discharge lasting more than three weeks, often associated with a perforated tympanic membrane.
The incidence of mastoiditis has significantly declined in the antibiotic era due to prompt treatment of otitis media. However, a recent shift toward conservative management of ear infections has led to a slight increase in cases in some regions. It remains a relatively rare condition, with incidence rates ranging from approximately 1.2 to 3.8 cases per 100,000 patient-years. Risk factors include inadequate treatment of otitis media, lack of vaccination against Streptococcus pneumoniae and Haemophilus influenzae, and the presence of cochlear implants.
The disease typically develops as an extension of infection from the middle ear into the mastoid air cells. In acute mastoiditis, the most common causative organisms mirror those of acute otitis media, including Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus pyogenes, and Pseudomonas aeruginosa. Chronic mastoiditis is often polymicrobial, involving organisms such as Pseudomonas aeruginosa, Staphylococcus aureus, gram-negative bacilli, anaerobes, and rarely fungi or mycobacteria.
Clinically, patients often present with symptoms of acute otitis media, including fever, ear pain, and hearing impairment. Physical examination reveals erythema of the tympanic membrane, ear discharge (otorrhea), and characteristic postauricular findings such as swelling, tenderness, and redness over the mastoid region. A key sign is displacement of the pinna outward and downward. In chronic cases, symptoms may be more subtle, including persistent ear discharge and hearing loss.
Diagnosis is supported by laboratory findings such as elevated white blood cell count and inflammatory markers (CRP and ESR). Imaging plays a crucial role, with radiographs showing destruction of mastoid air cell septa and fluid accumulation, while CT or MRI provides detailed assessment of disease extent and complications. Microbiological diagnosis is achieved through culture of ear discharge or middle ear fluid obtained via tympanocentesis.
Management requires prompt and aggressive treatment due to the risk of serious complications. Intravenous antibiotics are the mainstay of therapy, typically using broad-spectrum agents such as third- or fourth-generation cephalosporins, piperacillin-tazobactam, or combinations targeting resistant organisms. Treatment duration is usually 3–4 weeks, with transition to oral therapy after clinical improvement. Chronic mastoiditis may also require local antibiotic therapy and meticulous ear care.
Surgical intervention is indicated in cases of treatment failure, complications, or evidence of bone destruction. Procedures such as mastoidectomy are performed to remove infected tissue and prevent further spread. Less invasive approaches, including drainage and ventilation tube placement, may be considered in selected cases without intracranial involvement.
The prognosis is generally very good when mastoiditis is diagnosed early and treated appropriately. However, delayed or inadequate treatment can lead to serious complications, including subperiosteal abscess, facial nerve paralysis, intracranial infections such as meningitis or brain abscess, and permanent hearing loss.
