Dermatitis and Treatment Modalities

1. Describe dermatitis, diagnostic criteria, and treatment modalities
2. Describe the drug therapy for Conjunctivitis and Otitis Media
3. Discuss Herpes Virus infections, patient presentation, and treatment
4. Describe the most common primary bacterial skin infections and the treatment of choice.

answer individually

Dermatitis

Description

Dermatitis is a general term that describes inflammation of the skin. It encompasses several types, including atopic dermatitis (eczema), contact dermatitis, seborrheic dermatitis, and stasis dermatitis. Dermatitis can present with various symptoms such as redness, swelling, itching, and lesions. The condition can be acute or chronic, with flares and remissions.

Diagnostic Criteria

Diagnosis is primarily clinical, based on the appearance of the skin and patient history. Specific criteria include:

• Atopic Dermatitis: Pruritus, chronic or relapsing history, characteristic distribution and morphology (e.g., face, neck, and extensor surfaces in infants; flexural surfaces in children and adults), and family history of atopy.
• Contact Dermatitis: History of exposure to irritants or allergens, localized skin changes at the contact site.
• Seborrheic Dermatitis: Greasy scales on erythematous background, typically affecting scalp, face, and upper chest.
• Stasis Dermatitis: Associated with venous insufficiency, presenting with erythema, scaling, and hyperpigmentation over the lower legs.

Treatment Modalities

Treatment varies depending on the type of dermatitis:

• Atopic Dermatitis: Emollients to restore skin barrier, topical corticosteroids, calcineurin inhibitors (e.g., tacrolimus), and antihistamines for pruritus.
• Contact Dermatitis: Avoidance of irritants/allergens, topical corticosteroids, and emollients.
• Seborrheic Dermatitis: Antifungal agents (e.g., ketoconazole shampoo), topical corticosteroids, and zinc pyrithione shampoos.
• Stasis Dermatitis: Compression therapy, topical corticosteroids, emollients, and treatment of underlying venous insufficiency.

Drug Therapy for Conjunctivitis and Otitis Media

Conjunctivitis

Conjunctivitis, or “pink eye,” can be viral, bacterial, or allergic.

• Viral Conjunctivitis: Often self-limiting. Artificial tears and cold compresses can provide symptomatic relief. Topical antiviral agents are used in severe cases (e.g., HSV conjunctivitis treated with topical trifluridine).
• Bacterial Conjunctivitis: Broad-spectrum antibiotic eye drops or ointments such as erythromycin, tobramycin, or fluoroquinolones (e.g., moxifloxacin).
• Allergic Conjunctivitis: Antihistamine or mast cell stabilizer eye drops (e.g., olopatadine, ketotifen), artificial tears, and avoiding allergens.

Otitis Media

Otitis media is a common infection of the middle ear.

• Acute Otitis Media (AOM): First-line treatment typically includes amoxicillin. If there is no improvement or if the patient has a penicillin allergy, alternatives include amoxicillin-clavulanate, cefdinir, or azithromycin.
• Chronic Suppurative Otitis Media: May require topical antibiotic drops (e.g., ofloxacin) and sometimes systemic antibiotics.
• Pain Management: Analgesics such as acetaminophen or ibuprofen.

Herpes Virus Infections

Description and Patient Presentation

Herpes virus infections are caused by herpes simplex virus (HSV) types 1 and 2, and varicella-zoster virus (VZV).

• HSV-1 and HSV-2: Present with painful vesicular lesions on mucosal surfaces (oral for HSV-1 and genital for HSV-2). Recurrent infections are common.
• VZV: Causes chickenpox (varicella) in primary infection and shingles (herpes zoster) upon reactivation. Presents with a painful, unilateral vesicular rash in a dermatomal distribution.

Treatment

• HSV Infections: Antiviral therapy with acyclovir, valacyclovir, or famciclovir. Topical treatments may be used for oral herpes.
• VZV Infections: Antiviral therapy with acyclovir, valacyclovir, or famciclovir. Pain management includes analgesics and, for postherpetic neuralgia, gabapentin or pregabalin.

Primary Bacterial Skin Infections and Treatment

Common Infections

• Impetigo: Caused by Staphylococcus aureus or Streptococcus pyogenes. Presents with honey-colored crusted lesions, typically on the face and extremities.
• Cellulitis: Involves deeper dermis and subcutaneous tissues, commonly caused by S. aureus and S. pyogenes. Presents with erythema, swelling, warmth, and pain.
• Folliculitis: Infection of hair follicles, often caused by S. aureus, presenting as pustules centered on hair follicles.

Treatment

• Impetigo: Topical mupirocin or oral antibiotics such as cephalexin or dicloxacillin for extensive cases.
• Cellulitis: Oral or intravenous antibiotics depending on severity, typically cephalexin, dicloxacillin, or clindamycin. MRSA coverage with trimethoprim-sulfamethoxazole or doxycycline if indicated.
• Folliculitis: Topical mupirocin or clindamycin; oral antibiotics for more extensive cases.

Conclusion

Managing skin infections and inflammation involves accurate diagnosis and targeted treatment, often requiring a combination of topical and systemic therapies. Proper use of antibiotics and antiviral agents, along with symptomatic management, is crucial for effective care.