Vesiculobullous Diseases: Dermatitis Herpetiformis

Question 1

Dermatitis Herpetiformis

Clinical Feature. SYmp only

Answer 1

• grouped papules/vesicles/urticarial wheals on an erythematous base, associated with intense pruritus,
burning, stinging, excoriations
• lesions grouped, bilaterally symmetrical

Question 2

Dermatitis Herpetiformis. sites

Answer 2

• common sites: extensor surfaces of elbows/knees, sacrum, buttocks, scalp

Question 3

Dermatitis Herpetiformis.

Pathophysiology + gens

Answer 3

transglutaminase IgA deposits in the skin alone or in immune complexes leading to eosinophil and
neutrophil infilltration
• 90% have HLA B8, DR3, DQWZ

Question 4

Dermatitis Herpetiformis. Asoc Pathologies

Answer 4

• 90-100% associated with an often subclinical gluten-sensitive enteropathy (i.e. celiac disease)
• 30% have thyroid disease; increased risk of intestinal lymphoma in untreated comorbid celiac disease;
iron/folate deciency is common

Question 5

Dermatitis Herpetiformis Epidemiology

Answer 5

• 20-60 yr old, M:F = 2:1

Question 6

Dermatitis Herpetiformis Investigations

Answer 6

biopsy

• immunofluorescence shows IgA deposits in perilesional skin

Question 7

Dermatitis Herpetiformis Management

Answer 7

dapsone (sulfapyridine if contraindicated or poorly tolerated)
• gluten-free diet for life – this can reduce risk of lymphoma