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Pathology - Vitamin A Deficiency
Pathophysiology
Vitamin A is necessary for both the upkeep of the surface of the eyes and eyesight, particularly in the dark.
Additionally, normal immunological response as well as the growth and repair of epithelial cells depend on it. While it is rare in affluent nations, vitamin A insufficiency is widespread in poor nations. The majority of vitamin A is stored in the liver and released into the bloodstream with the use of a carrier protein. Vitamin A is a fat-soluble vitamin that is absorbed in the small intestine through the chylomicron pathway. Fat malabsorption-related disorders will reduce the absorption of vitamin A in the intestines, whereas liver disorders will reduce the storage of vitamin A.
The cycling of visual pigment molecules in the retina is insufficient to support vision in low light when retinal concentration is too low. The patient exhibits symptoms of poor surface upkeep, such as "Bittot's spots" and dry eyes. In children in the underdeveloped world, corneal scarring is a major cause of blindness and can happen. Recurrent colds and coughing are indicative of lowered immunity. Oral vitamin pills are a simple way to address the disease.
Pathophysiology
Vitamin A is necessary for both the upkeep of the surface of the eyes and eyesight, particularly in the dark.
Additionally, normal immunological response as well as the growth and repair of epithelial cells depend on it. While it is rare in affluent nations, vitamin A insufficiency is widespread in poor nations. The majority of vitamin A is stored in the liver and released into the bloodstream with the use of a carrier protein. Vitamin A is a fat-soluble vitamin that is absorbed in the small intestine through the chylomicron pathway. Fat malabsorption-related disorders will reduce the absorption of vitamin A in the intestines, whereas liver disorders will reduce the storage of vitamin A.
The cycling of visual pigment molecules in the retina is insufficient to support vision in low light when retinal concentration is too low. The patient exhibits symptoms of poor surface upkeep, such as "Bittot's spots" and dry eyes. In children in the underdeveloped world, corneal scarring is a major cause of blindness and can happen. Recurrent colds and coughing are indicative of lowered immunity. Oral vitamin pills are a simple way to address the disease.
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Pathology - Common Obesity
Pathophysiology
Excess adipose tissue is the condition known as common obesity. More than 25 kg/m2 is considered overweight, more than 30 kg/m2 is considered obese, and more than 40 kg/m2 is considered severely obese.
In America, the majority of adults are either overweight or obese.
Hypertension, type 2 diabetes, dyslipidemia, joint disease, and certain malignancies are examples of many comorbidities. An imbalance between energy intake and expenditure causes obesity and excess fat storage. The patient reports eating high-calorie fast food frequently and leads a sedentary lifestyle. The complicated pathophysiology governs hunger and satiety and is mediated by numerous neuronal and endocrine mechanisms that work through the hypothalamus. Leptin is a hormone secreted by adipose tissue that indicates an excess of fat storage. Normally, leptin's physiological negative feedback reduces appetite and raises calorie expenditure. One way to think of obesity is as a leptin resistance syndrome. Excess adipose tissue also releases other cytokines that are linked to insulin resistance, type 2 diabetes, and dyslipidemia. Hypertension is more likely when there is an increase in central sympathetic activity. Here, the high frequency of obesity in the entire family suggests that genetic factors play a significant role in obesity.
With supportive behavioral therapy, this patient—who is motivated to reduce weight—should be assisted in increasing his physical activity and reducing his energy intake.
Pathophysiology
Excess adipose tissue is the condition known as common obesity. More than 25 kg/m2 is considered overweight, more than 30 kg/m2 is considered obese, and more than 40 kg/m2 is considered severely obese.
In America, the majority of adults are either overweight or obese.
Hypertension, type 2 diabetes, dyslipidemia, joint disease, and certain malignancies are examples of many comorbidities. An imbalance between energy intake and expenditure causes obesity and excess fat storage. The patient reports eating high-calorie fast food frequently and leads a sedentary lifestyle. The complicated pathophysiology governs hunger and satiety and is mediated by numerous neuronal and endocrine mechanisms that work through the hypothalamus. Leptin is a hormone secreted by adipose tissue that indicates an excess of fat storage. Normally, leptin's physiological negative feedback reduces appetite and raises calorie expenditure. One way to think of obesity is as a leptin resistance syndrome. Excess adipose tissue also releases other cytokines that are linked to insulin resistance, type 2 diabetes, and dyslipidemia. Hypertension is more likely when there is an increase in central sympathetic activity. Here, the high frequency of obesity in the entire family suggests that genetic factors play a significant role in obesity.
With supportive behavioral therapy, this patient—who is motivated to reduce weight—should be assisted in increasing his physical activity and reducing his energy intake.
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Pathology - Acute Pancreatitis
Pathophysiology
The intrapancreatic activation of enzymes is the etiology of this inflammatory disease. Common symptoms include pain, nausea, vomiting, and intestinal ileus (seen here by a lack of bowel noises). Acute pancreatitis is frequently caused by trauma, drug side effects, hypertriglyceridemia, gallstones, and alcohol consumption.
Pancreatic autodigestion is accompanied by bleeding, necrosis, interstitial edema, intra-abdominal fluid accumulation, and the release of vasoactive peptides. The sickness can vary in severity and has the potential to be lethal. Increased AST/ALT and alkaline phosphatase levels, together with elevated serum amylase and lipase, are found in laboratory examination. If gallstone blockage is present, these levels are frequently accompanied by hyperbilirubinemia. Patients are treated with pain management, hydration support, and close observation to prevent complications like necrotizing disease or damage to the surrounding vascular structures.
Pathophysiology
The intrapancreatic activation of enzymes is the etiology of this inflammatory disease. Common symptoms include pain, nausea, vomiting, and intestinal ileus (seen here by a lack of bowel noises). Acute pancreatitis is frequently caused by trauma, drug side effects, hypertriglyceridemia, gallstones, and alcohol consumption.
Pancreatic autodigestion is accompanied by bleeding, necrosis, interstitial edema, intra-abdominal fluid accumulation, and the release of vasoactive peptides. The sickness can vary in severity and has the potential to be lethal. Increased AST/ALT and alkaline phosphatase levels, together with elevated serum amylase and lipase, are found in laboratory examination. If gallstone blockage is present, these levels are frequently accompanied by hyperbilirubinemia. Patients are treated with pain management, hydration support, and close observation to prevent complications like necrotizing disease or damage to the surrounding vascular structures.
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Pathology - Chronic Pancreatitis
Pathophysiology
There is a connection between chronic pancreatic insufficiency and chronic pancreatitis. Exocrine pancreatic insufficiency causes maldigestion and malabsorption of food, which leads to diarrhea and nasty feces. The loss of endocrine pancreatic function is indicated by hyperglycemia. Malnutrition and a particular decrease of B12 absorption, which requires pancreatic enzymes, can cause anemia. Despite the usual acute spike in blood lipase and amylase due to pancreatitis, this patient has a little amount of functional pancreatic tissue mass because to fibrosis and is in the late stages of chronic illness. The most prevalent cause of pathogenesis is chronic alcohol consumption, although there are numerous additional factors as well, such as gallstone disease, immunological disorders, and inherited diseases like cystic fibrosis.
It is believed that oxidative stress, toxicity from alcohol metabolism, duct blockage, and necrosis-fibrosis responses that occur after acute inflammation are responsible for the gland's destruction. Inflammation results from the gland's trypsinogen being activated improperly. Because of the pancreatic duct blockage, ischemia, necrosis, and inflammation, pain is a common observation. Imaging frequently reveals pancreatic duct dilating.
Pathophysiology
There is a connection between chronic pancreatic insufficiency and chronic pancreatitis. Exocrine pancreatic insufficiency causes maldigestion and malabsorption of food, which leads to diarrhea and nasty feces. The loss of endocrine pancreatic function is indicated by hyperglycemia. Malnutrition and a particular decrease of B12 absorption, which requires pancreatic enzymes, can cause anemia. Despite the usual acute spike in blood lipase and amylase due to pancreatitis, this patient has a little amount of functional pancreatic tissue mass because to fibrosis and is in the late stages of chronic illness. The most prevalent cause of pathogenesis is chronic alcohol consumption, although there are numerous additional factors as well, such as gallstone disease, immunological disorders, and inherited diseases like cystic fibrosis.
It is believed that oxidative stress, toxicity from alcohol metabolism, duct blockage, and necrosis-fibrosis responses that occur after acute inflammation are responsible for the gland's destruction. Inflammation results from the gland's trypsinogen being activated improperly. Because of the pancreatic duct blockage, ischemia, necrosis, and inflammation, pain is a common observation. Imaging frequently reveals pancreatic duct dilating.
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Pathology - Anoxic Brain Injury
Pathophysiology
A history of prolonged cardiac arrest that resulted in diminished brain perfusion may produce anoxic brain damage. The brain tissue becomes ischemic due to decreased perfusion. Watershed areas, or the regions of the brain between two arterial supplies that lose perfusion and become ischemic earliest after vascular insult, are the most susceptible to anoxic brain injury. The neocortex, basal ganglia, and hippocampal regions are the brain's watershed regions. Unfortunately, there is no cure for this person because neurons have a limited capacity for regeneration.
Pathophysiology
A history of prolonged cardiac arrest that resulted in diminished brain perfusion may produce anoxic brain damage. The brain tissue becomes ischemic due to decreased perfusion. Watershed areas, or the regions of the brain between two arterial supplies that lose perfusion and become ischemic earliest after vascular insult, are the most susceptible to anoxic brain injury. The neocortex, basal ganglia, and hippocampal regions are the brain's watershed regions. Unfortunately, there is no cure for this person because neurons have a limited capacity for regeneration.
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Pathology - Epidural Hematoma
Pathophysiology
Blunt head trauma can result in an epidural hematoma.
Ruptures of the middle meningeal artery arising from injuries to the temporoparietal area can cause epidural hematomas. This results in a biconvex lens-shaped collection of blood in the epidural space that does not cross suture lines. These individuals frequently experience lucid intervals, which are crucial for an early diagnosis. Some individuals may develop oculomotor palsy (cranial nerve III palsy) as a result of mass effect on the oculomotor nerve, which occurs when the hematoma compresses the brain in the direction of the midline. The mainstay of treatment is surgical blood extraction. Subdural hematomas are different from epidural hematomas in that they often develop more gradually, are caused by injury to the bridging veins, and have a crescent-shaped collection of blood because the suture lines have crossed.
Pathophysiology
Blunt head trauma can result in an epidural hematoma.
Ruptures of the middle meningeal artery arising from injuries to the temporoparietal area can cause epidural hematomas. This results in a biconvex lens-shaped collection of blood in the epidural space that does not cross suture lines. These individuals frequently experience lucid intervals, which are crucial for an early diagnosis. Some individuals may develop oculomotor palsy (cranial nerve III palsy) as a result of mass effect on the oculomotor nerve, which occurs when the hematoma compresses the brain in the direction of the midline. The mainstay of treatment is surgical blood extraction. Subdural hematomas are different from epidural hematomas in that they often develop more gradually, are caused by injury to the bridging veins, and have a crescent-shaped collection of blood because the suture lines have crossed.
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Pathology - Alzheimer's DIsease
Pathophysiology
The hallmark of Alzheimer's disease (AD) is a progressive decline in short-term memory and cognitive function. Amyloid plaques and neurofibrillary tangles are the histopathologic characteristics of AD. Hyperphosphorylated tau proteins, which are the building blocks of neurofibrillary tangles, have an impact on the microtubules that are a component of the neuronal transport system. The neuronal cells are poisoned by the beta-amyloid plaques. Due to the APP gene's location on chromosome 21, individuals with Down syndrome (trisomy 21) are more likely to develop early Alzheimer's disease. AD development is linked to mutations in the presenilin genes and APP, which can be hereditary or spontaneous. Furthermore, abnormalities in the secretase-mediated APP degradation pathway may result in beta-amyloid accumulation. Additionally, there is a correlation between AD and the apolipoprotein E allele's inheritance. Imaging studies of AD patients usually show atrophy of the temporal lobes, which is most likely caused by hippocampal neuron death brought on by a buildup of beta-amyloid plaques. Acetylcholinesterase inhibitors, like donepezil, or cholinergic medications, such galantamine and rivastigmine, are commonly used in treatment.
According to certain research, vitamin E has some utility as an adjuvant but not as a stand-alone treatment.
Pathophysiology
The hallmark of Alzheimer's disease (AD) is a progressive decline in short-term memory and cognitive function. Amyloid plaques and neurofibrillary tangles are the histopathologic characteristics of AD. Hyperphosphorylated tau proteins, which are the building blocks of neurofibrillary tangles, have an impact on the microtubules that are a component of the neuronal transport system. The neuronal cells are poisoned by the beta-amyloid plaques. Due to the APP gene's location on chromosome 21, individuals with Down syndrome (trisomy 21) are more likely to develop early Alzheimer's disease. AD development is linked to mutations in the presenilin genes and APP, which can be hereditary or spontaneous. Furthermore, abnormalities in the secretase-mediated APP degradation pathway may result in beta-amyloid accumulation. Additionally, there is a correlation between AD and the apolipoprotein E allele's inheritance. Imaging studies of AD patients usually show atrophy of the temporal lobes, which is most likely caused by hippocampal neuron death brought on by a buildup of beta-amyloid plaques. Acetylcholinesterase inhibitors, like donepezil, or cholinergic medications, such galantamine and rivastigmine, are commonly used in treatment.
According to certain research, vitamin E has some utility as an adjuvant but not as a stand-alone treatment.
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Pathology - Normal Pressure Hydrocephalus
Pathogenesis
Normal pressure hydrocephalus (NPH) is characterized by the typical trifecta of symptoms: urine incontinence, dementia, and gait abnormalities.
The three Ws stand for wet (urinary incontinence), wacky (dementia), and wobbly (gait disturbance), and are a useful acronym for remembering the trio. Cerebrospinal fluid (CSF) builds up as a result of reduced resorption at the arachnoid villi, causing non-pulmonary hydrolysis (NPH). CSF pressures are elevated but still fall within the normal range. The corticospinal tract fibers that pass through the internal capsule often stretch first, causing gait difficulty. Later in the course of the disease, disinhibition of bladder contractility leads to urinary incontinence. To determine whether the patient's symptoms have improved once the volume of CSF that is circulating is decreased, lumbar punctures can be done. Patients eventually require a ventriculoperitoneal shunt in order to stop the accumulation of CSF.
Pathogenesis
Normal pressure hydrocephalus (NPH) is characterized by the typical trifecta of symptoms: urine incontinence, dementia, and gait abnormalities.
The three Ws stand for wet (urinary incontinence), wacky (dementia), and wobbly (gait disturbance), and are a useful acronym for remembering the trio. Cerebrospinal fluid (CSF) builds up as a result of reduced resorption at the arachnoid villi, causing non-pulmonary hydrolysis (NPH). CSF pressures are elevated but still fall within the normal range. The corticospinal tract fibers that pass through the internal capsule often stretch first, causing gait difficulty. Later in the course of the disease, disinhibition of bladder contractility leads to urinary incontinence. To determine whether the patient's symptoms have improved once the volume of CSF that is circulating is decreased, lumbar punctures can be done. Patients eventually require a ventriculoperitoneal shunt in order to stop the accumulation of CSF.
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Pathology - Absence Seizures
Pathophysiology
Petit mal seizures were the previous name for absence seizures.
The majority of absence seizures occur in childhood and are characterized by brief (few seconds) episodes of altered consciousness that frequently manifest as gazing episodes. Lip-smacking and other automatisms (brief, unconscious activities) may be present in patients. In most cases, they have no postictal confusion and no memory of the incident or the passing of time. The EEG wave pattern and spike at 3 Hz are indicative of this diagnosis. Hyperventilation, which lowers carbon dioxide levels, can also cause seizures. Etosuximide is the preferred medication for the condition. Treatment usually has a positive effect on the patients, and by adulthood, the seizures frequently stop altogether.
Pathophysiology
Petit mal seizures were the previous name for absence seizures.
The majority of absence seizures occur in childhood and are characterized by brief (few seconds) episodes of altered consciousness that frequently manifest as gazing episodes. Lip-smacking and other automatisms (brief, unconscious activities) may be present in patients. In most cases, they have no postictal confusion and no memory of the incident or the passing of time. The EEG wave pattern and spike at 3 Hz are indicative of this diagnosis. Hyperventilation, which lowers carbon dioxide levels, can also cause seizures. Etosuximide is the preferred medication for the condition. Treatment usually has a positive effect on the patients, and by adulthood, the seizures frequently stop altogether.
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Pathology - Herpes Simplex Virus Encephalitis
Pathogenesis
Herpes Simplex Virus (HSV) involvement in the frontotemporal region might result in seizures. The temporal lobes are particularly susceptible to the virus's influence, which results in seizures and the accompanying symptoms of temporary aphasia. The brain parenchyma in the left motor cortex and temporal lobes is implicated in seizures when just the right side of the body is affected. Jacksonian march, or following somatotopic organization, is a seizure pattern that can be seen in primary motor cortex seizures. One of two possible causes of HSV encephalitis is the reactivation of a latent infection or original HSV infection. Predominant lymphocytosis, normal glucose, and normal protein in the CSF study indicate a viral origin (bacteria would induce a reduction in glucose and an increase in neutrophils). Seizures are prevented and acyclovir is used as treatment. This is regarded as a neurological emergency due to the disease's quick progression, and urgent treatment is essential.
Pathogenesis
Herpes Simplex Virus (HSV) involvement in the frontotemporal region might result in seizures. The temporal lobes are particularly susceptible to the virus's influence, which results in seizures and the accompanying symptoms of temporary aphasia. The brain parenchyma in the left motor cortex and temporal lobes is implicated in seizures when just the right side of the body is affected. Jacksonian march, or following somatotopic organization, is a seizure pattern that can be seen in primary motor cortex seizures. One of two possible causes of HSV encephalitis is the reactivation of a latent infection or original HSV infection. Predominant lymphocytosis, normal glucose, and normal protein in the CSF study indicate a viral origin (bacteria would induce a reduction in glucose and an increase in neutrophils). Seizures are prevented and acyclovir is used as treatment. This is regarded as a neurological emergency due to the disease's quick progression, and urgent treatment is essential.
