Name
DERMATITIS, HERPETIFORMIS
DESCRIPTION
DETAIL
CAUSES : UNKNOWN -------------------------------------------------------------------------- DIFFERENTIAL DIAGNOSIS : β’ Scabies β’ Erythema multiforme β’ Bullous pemphigoid β’ Linear IgA disease β’ Transient acantholytic dermatosis β’ Subcorneal pustular dermatosis β’ Erythema elevatum diutinum β’ Papular urticaria β’ Eczema β’ Tinea corporis β’ Excoriations* Abnormal thyroid function tests may occur SPECIAL TESTS : Direct immunofluorescence reveals granular IgA deposition in the dermal papilla IMAGING : Thyroid scan if indicated by physical exam DIAGNOSTIC PROCEDURES : β’ Skin biopsy β’ IgA anti-endomysial antibodies
TYPENOTES
RISK FACTORS : Gluten-sensitive enteropathy, Family history of dermatitis herpetiformisDRUG(S) OF CHOICE : Dapsone 50 mg per day will usually improve symptoms within 24 to 48 hours in adults. Average maintenance dose is 25 to 200 mg per day. ALTERNATIVE DRUGS : Sulfapyridine, colchicine, prednisone, tetracycline plus nicotinamide, cyclosporin, systemic steroids, topical steroids PATIENT MONITORING : β’ Baseline CBC and liver function studies should be obtained β’ G6PD should be quantifi ed in Asians, blacks and those of southern Mediterranean descent β’ CBC should be checked weekly for fi rst month, monthly for the next fi ve months and semi-annually thereafter β’ Chemistry profi le should be checked every six months β’ Patient should be made aware of potential hemolytic anemia and the blue-gray discoloration associated with methemoglobinemia EXPECTED COURSE/PROGNOSIS : β’ Patients respond dramatically to dapsone β’ Strict adherence to a gluten-free diet will produce improvement of clinical symptoms and a decrease in dapsone requirement in the majority of patients β’ Occasional new lesions (2-3 per week) are to be expected and are not an indication for altering daily dosage DIET : Clinical improvement occurs with gluten-free diet
RELATED DISEASE
Not Available Disease
DISEASE
INVESTIGATION
COMPLETE BLOOD COUNT, THYROID SCAN, BIOPSY, THYROID PROFILE