A 9-month-old infant develops symmetrical vesicobullous and eczematous lesions around the mouth, anus, and on the hands and feet, along with chronic diarrhea and diffuse alopecia. Symptoms began shortly after weaning from breast milk. Serum alkaline phosphatase is low for age.

• A Langerhans cell histiocytosis
• B Kwashiorkor with flaky paint dermatosis
• C Acrodermatitis enteropathica due to zinc deficiency ✓
• D Congenital syphilis

Explanation

Acrodermatitis enteropathica is an autosomal recessive defect of zinc absorption (SLC39C4 gene) presenting around weaning with the triad of periorificial and acral dermatitis, diarrhea, and alopecia. Alkaline phosphatase is a zinc-dependent metalloenzyme, so it falls in zinc deficiency, a useful corroborating clue. Kwashiorkor edema and hair pigment changes are absent here, LCH typically involves the scalp and seborrheic areas with petechiae, and congenital syphilis features palmoplantar rash with hepatosplenomegaly and snuffles.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.