Dermatology MCQ - Viral Infections - Personal protective equipment (PPE) related skin disorders

A 35-year-old healthcare worker develops erythema, papules, and scaling in the areas covered by her N95 mask and face shield after long shifts in the COVID-19 ICU. She reports itching and burning. The lesions are sharply demarcated to the sites of contact. Which of the following is the most likely diagnosis and the primary pathophysiological mechanism?

A) Irritant contact dermatitis; skin barrier disruption from friction, moisture, and pressure
B) Allergic contact dermatitis; type IV hypersensitivity to rubber accelerators or adhesives
C) Acne mechanica; follicular occlusion from pressure and friction
D) Pressure urticaria; mast cell degranulation from sustained pressure
E) Seborrheic dermatitis; Malassezia yeast overgrowth in sebum-rich areas

Correct Answer: A) Irritant contact dermatitis; skin barrier disruption from friction, moisture, and pressure

Explanation

This presentation is classic for irritant contact dermatitis (ICD) caused by prolonged use of personal protective equipment (PPE), such as masks, goggles, and face shields.

Key Clinical Features of PPE-Related ICD:

• Location: Sharply demarcated to areas of PPE contact (e.g., bridge of nose, cheeks, forehead, behind ears).

• Symptoms: Burning, stinging, itching, and pain.

• Signs: Erythema, papules, scaling, and sometimes fissures or erosions.

• Timing: Develops after repeated or prolonged exposure to PPE.

Pathophysiology:

• Skin Barrier Disruption:

  • Friction from tight-fitting PPE.

  • Occlusion and moisture buildup (sweat, humidity) under PPE.

  • Pressure points (e.g., from mask nose wire, goggles).

• This leads to damage of the stratum corneum, allowing penetration of irritants and loss of skin integrity.

• Not immune-mediated (unlike allergic contact dermatitis).

Why Not the Other Options?

• (B) Allergic contact dermatitis: Would involve a type IV hypersensitivity reaction to specific allergens (e.g., thiuram in rubber straps, formaldehyde in adhesives). It typically presents with vesicles and intense itching and may spread beyond the contact area. Less common than ICD in PPE-related cases.

• (C) Acne mechanica: Caused by heat, pressure, and friction leading to follicular occlusion. Presents with papules and pustules in areas under PPE, but lacks scaling and is more focused on hair follicles.

• (D) Pressure urticaria: Presents with wheals at sites of pressure after a delay (4-6 hours), not scaling or papules.

• (E) Seborrheic dermatitis: Presents with greasy scales in sebum-rich areas (scalp, nasolabial folds), not strictly limited to PPE contact sites.

Management:

• Barrier protection: Apply silicone-based barrier creams or films before donning PPE.

• Moisturizers: Use fragrance-free emollients after removing PPE to restore skin barrier.

• Proper PPE fit: Adjust to reduce friction and pressure.

• Topical corticosteroids: Low-potency (e.g., hydrocortisone 1%) for inflammation if needed.

Prevention:

• Skin checks: Regular inspection and early intervention.

• Rotate PPE: If possible, alternate types to reduce prolonged pressure on one area.

Note: PPE-related skin injury is common among healthcare workers. ICD is the most frequent cause, but allergic contact dermatitis should be considered if symptoms persist despite preventive measures. Always assess for both in refractory cases.