Dermatitis herpetiformis

Diagnosis: Dermatitis herpetiformis

Dermatitis herpetiformis

Clinical Presentation

Dermatitis herpetiformis

Clinical History

Intensely pruritic, grouped papulovesicles on extensor surfaces (elbows, knees, buttocks). GI symptoms may be absent. Evaluate for celiac disease with tissue transglutaminase antibodies.

Treatment

Dapsone 50-150 mg/day (rapid response within days). Check G6PD before starting. Gluten-free diet (GFD) — can reduce or eliminate need for dapsone after months. Monitor CBC for dapsone-related hemolysis and methemoglobinemia.

Differential Diagnosis

• Linear IgA bullous dermatosis • Scabies • Eczema/atopic dermatitis • Bullous pemphigoid • Erythema multiforme • Prurigo nodularis • Insect bite reactions

Key Learnings

• Pathognomonic cutaneous manifestation of celiac disease — virtually all patients have gluten-sensitive enteropathy • Classic DIF: granular IgA deposits at dermal papillae tips — this is the diagnostic gold standard • Symmetrical distribution: elbows, knees, buttocks, shoulders, sacrum • Intensely pruritic — vesicles often excoriated by the time of examination • Responds dramatically to dapsone (often within 24-48 hours) • Gluten-free diet is the only treatment that addresses both skin and GI disease • Check G6PD before starting dapsone (risk of hemolytic anemia)

Tags: Dermatitis herpetiformis, dermatologist, dermatology, kodachrome