​Kembara Xtra - Medicine- Cellulitis

​Kembara Xtra - Medicine- Cellulitis 
Introduction 
With more than 650,000 admissions each year in the United States, skin infections are a significant health burden.
An acute bacterial infection that affects the dermis and subcutaneous tissue.
Orbital cellulitis is an infection of the eye posterior to the septum; sinusitis is the most common risk factor. Periorbital cellulitis is a bacterial infection of the eyelid and surrounding tissues.
- Facial cellulitis: preceded by otitis media or an upper respiratory infection
- Buccal cellulitis: a cheek infection in infants linked to bacteremia that was prevalent prior to receiving the Haemophilus influenzae type B vaccination
Children frequently get peritonsillar cellulitis, which is characterized by fever, sore throat, and "hot potato" speech. Perianal cellulitis is characterized by clearly delineated, brilliant perianal erythema.
- Necrotizing cellulitis: lower extremities infected with germs that produce gas; more prevalent in diabetics

Incidence and Prevalence in Epidemiology 
Males predominate over females. Seasonality hospitalizations for cellulitis are more common in the summer and less common in the winter. 
Incidence
 In 2015, there were 27 annual visits per 1,000 persons for purulent SSTI; 200/100,000 patient years ranged from 0.2 to 24.6 visits per 1000 people per year.
Prevalence
Purulent skin and soft tissue infection (SSTI) visits to U.S. ambulatory offices ranging from 5.4 to 11.35 million visits annually (1); 3.3 million new cases in the country in 2012 costing $15 billion.

Pathophysiology 
Bacterial invasion occurs when the skin's outermost layer, or epidermis, is breached, leading to cellulitis.
Biology, micro
The most prevalent pathogens are gram-negative aerobic bacilli, Staphylococcus aureus, including MRSA, and hemolytic streptococci (groups A, B, C, G, and F).
S. aureus and Pseudomonas aeruginosa are both seen in patients with periorbital and orbital cellulitis and IV drug users, respectively.
- Buccal cellulitis is caused by H. influenza.
- Necrotizing cellulitis caused by clostridium and non-spore-forming anaerobes (crepitant/gangrenous)
- Cellulitis caused by Streptococcus agalactiae after lymph node dissection
- Streptococcus iniae: immunocompromised hosts - Pasteurella multocida and Capnocytophaga canimorsus: cellulitis preceded by bites
– Mycobacterium, fungal (syphilis, aspergillosis, mucormycosis)
Genetics
no inherited pattern

Risk factors include: Skin barrier disruption from trauma, infection, bug bites, drug injections, body piercing, and maceration Inflammation from radiation therapy or excoriating skin conditions Edema from venous insufficiency; lymphatic obstruction from surgery or congestive heart failure (CHF)
Age, diabetes, hypertension, obesity, tinnitus, prior cellulitis, and recurrent cellulitis are all risk factors for the infection.
- Cellulitis recurrence score (predicts recurrence of lower extremity cellulitis based on presence of lymphedema, chronic venous insufficiency, peripheral vascular disease, and deep venous thrombosis) - Recurrent cellulitis is seen in immunocompromised patients (HIV/AIDS), steroids and TNF-α inhibitor therapy, diabetes, hypertension, cancer, peripheral arterial or venous diseases, chronic kidney disease, dialysis, IV or SC drug use.


Prevention measures include elevating the affected area, wearing compression socks, and using pneumatic pressure pumps to reduce edema. Diabetic patients should also maintain glycemic control and take good care of their feet.


Accompanying Conditions 
Obesity, venous insufficiency, lymphedema, and abscess

Diagnosis 

A fast developing unilateral area of erythema, warmth, swelling, and/or discomfort is a sign of the clinical diagnosis.

Providing the Past Portals of entry include prior trauma, surgery, animal or human bites, dermatitis, and fungus infections.
Aching, burning, or itching Chills, fever, and malaise


clinical assessment 
Check vital signs for stability in hemodynamics.
Regional lymphadenopathy, purulent discharge, localized pain and discomfort with erythema, induration, swelling, and warmth.
Proptosis, globe displacement, ocular movement restriction, vision loss, and diplopia are all symptoms of orbital cellulitis.

Malaise, anorexia, vomiting, itchiness, burning, and anterior neck swelling are symptoms of facial cellulitis.

Multiple Diagnoses 
erythema nodosum, sunburn, insect bites, deep vein thrombosis, thrombophlebitis, bursitis, dermatitis, herpes zoster, osteomyelitis, malignancy, and toxic shock syndrome


Diagnostic tests and laboratory results 

Initial examinations (lab, imaging)
Blood cultures, CPK, and CRP should be ordered if there are symptoms of a systemic disease (fever, heart rate greater than 100 beats per minute, or systolic blood pressure less than 90 mm Hg). Think about serum lactate levels.
Plain radiographs, CT scans, and MRIs are helpful in cases of osteomyelitis, fracture, necrotizing fasciitis, and retained foreign bodies. Open wounds should be swabbed for culture.
For assessing any potential underlying abscesses, MRI and ultrasound are the most helpful diagnostic tools.
Procalcitonin is not helpful in the diagnosis of early cellulitis. Gallium-67 scintigraphy aids in the detection of cellulitis superimposed on chronic limb lymphedema.
Other/Diagnostic Procedures
When children with H. influenzae type B or display meningeal symptoms and face cellulitis, lumbar puncture should be considered.

Administration General Therapy 
Sterile saline dressings or cool aluminum acetate compresses for pain alleviation Immobilize/elevate afflicted leg to minimize swelling Edema: compression stockings, pneumatic pumps; diuretic medication for CHF patients 
Mark the erythema's borders to track its development and how well it responds to treatment. If necessary, get a tetanus shot.


The First Line of Medicine
Target treatment for known pathogens and/or specific exposures, such as animal bites
Choosing an empiric antibiotic:
- Cellulitis that isn't purulent
Treatment should concentrate on MSSA and -hemolytic streptococci in cases of nonpurulent discharge.
 Outpatient: treatment lasts 5 to 10 days (5)[C]; studies have indicated that shorter courses of 5 days are equally beneficial as longer courses.
Cephalexin 500 mg PO every six hours (orally) for mild cellulitis; children: 25 to 50 mg/kg/day in three to four doses
Children should take 25 to 50 mg/kg of dicloxacillin four times daily.
Clindamycin 300–450 mg PO every 6–8 hours; for children, 20–30 mg/kg daily in 4 doses
Cefazolin 1 to 2 g IV q8h; children: 100 mg/kg/day IV in 2 to 4 divided doses; Oxacillin 2 g IV q4h; children: 150 to 200 mg/kg/day IV in 4 to 6 doses; IV: for quickly progressive cellulitis
Clindamycin 600 to 900 mg IV every eight hours; children: 25 to 40 mg/kg/day IV in three to four doses; Nafcillin 2 g IV every four hours;
- Purulent cellulitis (likely CA-MRSA): Culture purulent wounds and check back in 48 hours.
Incise abscesses, drain them, and begin empiric antibiotic therapy. Adapt duration based on clinical response; modify based on culture results:
Oral: Trimethoprim-sulfamethoxazole (TMP-SMX) 1 DS pill PO BID; children: dose based on TMP at 8 to 12 mg/kg/day divided in 2 doses; Clindamycin 300 to 450 mg PO; Children: 40 mg/kg/day in 3 to 4 days
Doxycycline 100 mg PO BID; for children older than 8 years old who weigh more than 45 kg, the dosage is 100 mg PO BID.
Linezolid 600 mg PO BID; children 12 years: 10 mg/kg/dose (maximum 600 mg/dose); Minocycline 200 mg PO once and then 100 mg PO BID; Children >8 years: 4 mg/kg PO once and then 4 mg/kg PO BID. 12 years: 600 mg PO BID; PO TID
Tedizolid 200 mg PO once daily; children: No recommended dosage has been determined.
Vancomycin 15 to 20 mg/kg/dose IV every 8 to 12 hours; Daptomycin 4 mg/kg/dose IV once daily; if bacteremia is present or suspected: 6 mg/kg IV once daily; Linezolid 600 mg IV BID; Tedizolid 200 mg IV once daily; Ceftaroline 600 mg IV q12h; Tigecycline 100 mg IV once, then 50 mg IV q12h; Necrotizing cellulitis: requires broad-spectrum
Penicillin plus gentamicin or fluoroquinolones are penicillinase-resistant medications for fresh water exposure; doxycycline 200 mg IV in two separate doses is a medication for salt water exposure.
Bites: Amoxicillin and clavulanic acid are suggested treatments for both human and canine bites. For animal or human bites, the combination of ticarcillin and clavulanic acid or a third-generation cephalosporin (such as ceftriaxone) with metronidazole is an appropriate parenteral therapy. Use fluoroquinolone along with metronidazole if you are allergic to penicillin.
Ceftriaxone IV for adult facial cellulitis

 Cephalexin, cephalexin plus doxycycline, or TMP-SMX plus amoxicillin clavulanate are all effective treatments for mild-to-moderate diabetic foot infections.
- Severe: combinations of antibiotics that target both gram-positive and gram-negative aerobes as well as anaerobes, such as ampicillin-sulbactam, imipenem-cilastatin, or meropenem; alternatively
Admit for empiric antibiotic therapy covering MRSA if there are signs of serious infection, toxicity, immunocompromised patients, or worsening illness despite empirical therapy.
Recurrent streptococcal cellulitis: penicillin 250 mg BID, or erythromycin 250 mg BID if penicillin allergy.
Dalbavancin, a second-generation lipoglycopeptide antibiotic that covers MRSA, can be used to treat cellulitis and is only needed to be taken once a week.
Child Safety Considerations

The Melbourne ASSET tool is useful in detecting the requirement for IV antibiotics in pediatric populations (sensitivity 60%, specificity 93%). Avoid doxycycline in children under the age of 8 and during pregnancy.

Erythromycin 500 mg PO every six hours in the event of a mild illness and a penicillin allergy.

Débridement for gas and pustular materials is one surgical procedure. Cellulitis of the head or neck may require intubation or tracheotomy.

Admission Marked systemic toxicity or worsening symptoms that do not go away after 24 to 48 hours of therapy Patients with underlying risk factors or severe comorbidities Patients with severe infection, tissue necrosis, or severe pain

Patient Follow-Up Monitoring
If the patient remains toxic or not improving, repeat the pertinent blood tests. Symptomatic improvement often happens in 24 to 48 hours, but visual improvement may take 72 hours.

dietary intake 
Sugar regulation in diabetics

Other
Excellent  skin care

In patients with recurrent cellulitis, low-dose penicillin prophylaxis reduces recurrence.

It has been demonstrated that older age, higher BMI, and diabetes mellitus reduce the early response to antibiotics.

Complications include bacterial meningitis, gangrene, local abscess, bacteremia, sepsis, superinfection with gram-negative organisms, lymphangitis, thrombophlebitis or venous thrombosis, and sepsis.

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