Full Answer Section

• Stasis Dermatitis: Occurs on the lower legs due to poor circulation and venous insufficiency, leading to swelling, discoloration, itching, and scaling.
• Dyshidrotic Eczema (Pompholyx): Characterized by itchy, fluid-filled blisters, usually on the palms, soles, and sides of the fingers and toes.

Diagnostic Criteria (General Principles):

Diagnosis of dermatitis is primarily clinical, based on patient history, symptoms, and physical examination of the skin. Specific diagnostic criteria vary slightly for each type:

• Clinical Presentation:
  • Symptoms: Itching (pruritus) is the cardinal symptom, often severe. Other common symptoms include redness (erythema), dry skin, scaling, blistering, oozing, crusting, and thickening of the skin (lichenification) from chronic scratching.
  • Location and Distribution: The location of the rash can offer clues (e.g., flexural creases for atopic dermatitis, contact areas for contact dermatitis, scalp/face for seborrheic dermatitis, lower legs for stasis dermatitis).
  • Course: Chronic and relapsing (atopic, seborrheic) vs. acute and resolving (acute contact).
• Patient History:
  • Personal and Family History: History of allergies, asthma, eczema (for atopic dermatitis).
  • Exposures: Recent contact with new substances (soaps, detergents, plants, metals) for contact dermatitis.
  • Aggravating Factors: Triggers like stress, hot showers, certain fabrics, weather changes.
  • Occupation/Hobbies: Relevant exposures.
• Physical Examination: Visual inspection of the skin lesions, assessing their morphology (macules, papules, vesicles, plaques), distribution, and signs of secondary infection.
• Exclusion of Other Conditions: Ruling out other skin conditions with similar appearances (e.g., psoriasis, fungal infections, scabies).
• Specific Tests (if indicated):
  • Patch Testing: For suspected allergic contact dermatitis, involves applying small amounts of potential allergens to the skin and observing reactions after 48-96 hours.
  • Skin Biopsy: Rarely needed for routine diagnosis, but may be performed in atypical cases or to rule out other dermatological conditions.
  • Blood Tests: Generally not diagnostic for dermatitis, but may be used to rule out systemic conditions.
  • Skin Swabs/Cultures: If secondary bacterial or fungal infection is suspected.

Treatment Modalities:

Treatment aims to reduce inflammation, alleviate itching, restore the skin barrier, and prevent flares.

1. General Measures/Self-Care (Cornerstone of Management):

   • Moisturizing: Frequent and liberal application of emollients (creams, ointments) to hydrate the skin and restore the skin barrier, especially after bathing. Ointments are often more effective than lotions.
   • Avoidance of Triggers: Identifying and avoiding irritants (harsh soaps, perfumes, hot water, rough fabrics) and allergens.
   • Lukewarm Baths/Showers: Short baths with lukewarm water, possibly with colloidal oatmeal.
   • Gentle Cleansers: Use mild, fragrance-free, soap-free cleansers.
   • Avoid Scratching: Keep nails short, consider gloves at night.
   • Stress Management: Stress can exacerbate many forms of dermatitis.

2. Topical Medications:

   • Corticosteroids: First-line for acute flares. Available in various potencies (low to high). Applied directly to the inflamed skin to reduce itching and inflammation. Potency and duration of use depend on severity and location.
   • Calcineurin Inhibitors (e.g., Tacrolimus, Pimecrolimus): Non-steroidal alternatives for sensitive areas (face, skin folds) or for long-term maintenance, especially in atopic dermatitis. They modulate the immune response in the skin.
   • PDE4 Inhibitors (e.g., Crisaborole): Topical anti-inflammatory medication for mild-to-moderate atopic dermatitis.
   • Topical Antibiotics: For localized secondary bacterial infections (e.g., mupirocin).
   • Antifungal Creams: For seborrheic dermatitis (e.g., ketoconazole shampoo/cream).

3. Oral/Systemic Medications (for severe or widespread cases):

   • Oral Antihistamines: For symptom relief, especially sedating ones at night to aid sleep (e.g., diphenhydramine) or non-sedating for daytime itching.
   • Oral Corticosteroids: For severe, acute flares that don’t respond to topical treatment. Used short-term due to significant side effects with prolonged use.
   • Systemic Immunosuppressants (e.g., Cyclosporine, Azathioprine, Methotrexate): For severe, recalcitrant cases of atopic dermatitis or other forms of severe dermatitis not controlled by other therapies.
   • Biologic Agents (e.g., Dupilumab, Tralokinumab, Lebrikizumab): Monoclonal antibodies that target specific inflammatory pathways (e.g., IL-4/IL-13) involved in atopic dermatitis. Used for moderate to severe cases unresponsive to conventional therapies.
   • Oral Antibiotics: For widespread secondary bacterial infections (e.g., cellulitis).

4. Phototherapy (Light Therapy):

   • Description: Exposure to controlled amounts of ultraviolet (UV) light (UVA, UVB, or narrowband UVB).
   • Goal: Reduces inflammation and itching, often used for chronic, widespread atopic dermatitis.

Drug Therapy for Conjunctivitis and Otitis Media

Conjunctivitis (“Pink Eye”)

Inflammation of the conjunctiva (the membrane lining the eyelids and covering the white part of the eye). It can be bacterial, viral, or allergic.

• Bacterial Conjunctivitis:
  • Drug Therapy: Topical antibiotic eye drops or ointments are the mainstay.
    • Common choices: Erythromycin ophthalmic ointment, polymyxin B-trimethoprim drops, fluoroquinolone drops (e.g., moxifloxacin, ciprofloxacin) for more severe cases or contact lens wearers.
    • Duration: Typically 5-7 days.
  • Rationale: To eradicate the bacterial infection, reduce symptoms, and prevent spread.
  • Note: Mild cases can sometimes resolve on their own, but antibiotics reduce duration and contagiousness.
• Viral Conjunctivitis:
  • Drug Therapy: Primarily supportive. No specific antiviral eyedrops are routinely used for common viral conjunctivitis (adenovirus).
    • Supportive care: Artificial tears for lubrication, cool compresses for comfort, and sometimes topical vasoconstrictors/antihistamines for itching/redness.
    • Specific cases: Antiviral agents (e.g., ganciclovir gel, trifluridine drops) may be used if herpes simplex virus (HSV) is suspected (herpes keratitis), but this is a more serious condition.
  • Rationale: Viral conjunctivitis is usually self-limiting (resolves in 1-3 weeks). Treatment focuses on symptom relief.
• Allergic Conjunctivitis:
  • Drug Therapy: Topical medications are preferred.
    • Antihistamine eye drops: (e.g., olopatadine, azelastine, ketotifen) for rapid relief of itching and redness.
    • Mast cell stabilizers: (e.g., cromolyn sodium) for preventing symptoms, often used prophylactically before allergen exposure.
    • Dual-acting agents: (antihistamine + mast cell stabilizer) are common.
    • Topical NSAIDs: For severe itching.
    • Topical corticosteroids: Short-term use for very severe, acute allergic reactions under ophthalmologist supervision due to side effects (e.g., glaucoma, cataracts).
  • Rationale: To block the allergic reaction, reduce inflammation, and alleviate symptoms.

Otitis Media (Middle Ear Infection)

Inflammation of the middle ear, most commonly acute otitis media (AOM), often caused by bacterial or viral infections.

• Bacterial Acute Otitis Media (AOM):
  • Drug Therapy: Oral antibiotics are the primary treatment.
    • First-line: Amoxicillin (high dose: 80-90 mg/kg/day for children) is the drug of choice for most cases due to its efficacy, safety, and narrow spectrum.
    • Second-line/Resistant cases/Recent antibiotic use/Co-occurring conjunctivitis: Amoxicillin-clavulanate (Augmentin).