ANSWER: X-linked Dominant (XLD)Syndromes- Test Question

The correct answer is E. Incontinentia pigmenti

Correct Answer Explanation

Incontinentia pigmenti (IP) is an X-linked dominant disorder with skin lesions that follow the lines of Blaschko. It is characterized by four cutaneous stages: 1) inflammatory/vesicular; 2) verrucous; 3) hyperpigmented; 4) hypopigmented/atrophic. Stage 1 IP typically presents with linear erythema and vesicles during the first few weeks to months of life in an otherwise healthy baby girl. Vesiculobullous lesions are most common on the limbs and scalp, frequent on the trunk, and rare on the face. They resolve within days to weeks and are often replaced by verrucous linear plaques (stage 2) favoring the extremities and usually disappear late in infancy. Neonatal IP can usually be distinguished from other infectious conditions (i.e. scabies, herpes zoster, varicella, and other viral infections) by the child’s well-being, characteristic distribution, and a skin scraping. The early inflammatory phase demonstrates eosinophilic spongiosis and scattered dyskeratotic keratinocytes.

Incorrect Answer Explanation

A – Acropustulosis of infancy is a pruritic acral vesiculopustular eruption. The onset is usually between 3-6 months of age in classic form. It recurs in crops, typically every 3-4 weeks, with decreased frequency and severity over time; the classic form usually resolves completely by about 3 years of age. Symptomatic therapy with potent topical steroids and oral antihistamines is the gold standard.

B – Eosinophilic pustular folliculitis of infancy is characterized by recurrent pruritic crops of follicular vesiculopustules. It favors the scalp and face and occasionally involves the trunk and extremities. Therapy is symptomatic and spontaneous resolution usually occurs by 3 years of age.

C – Autosomal dominant hyper-IgE syndrome is a primary immunodeficiency syndrome with autosomal dominant inheritance due to STAT3 mutations. It is characterized by neonatal papulopustular and vesicular lesions with crusting favoring the face, scalp, and neck as well as the axillae and diaper area. During the first few weeks to months of life, serum IgE levels may not yet be elevated and other features such as cold abscesses, eczematous dermatitis, and recurrent infections are often absent.

D – Congenital erosive and vesicular dermatosis is a condition that typically presents at birth. The neonates, almost all of whom are premature, present with widespread erosions, vesicles, crusting, and scalded skin-like erythematous areas affecting up to 75% of the body surface area. Associated findings include collodion-like membrane, transparent areas of skin, livedo reticularis-like vascular pattern, and ulcerations. The lesions heal in 1-2 months with characteristic reticulate scars that often cover large areas of skin.