Dermatitis herpetifomis is associated with:
Ans: (b) HLA DQ2 and HLA DQ8HLA Associations in Bullous DisordersDiseaseAutoantibodiesHLA AssociationPemphigus vulgarisDg IIIHLA DR4*HLADR6HLADQ8HLADR14Pemphigus foliaceusDglHLA DR1*HLA DR4HLADR14Epidermolysis bullosa acquisitaCollagen type VIIHLA DR2*Dermatitis herpetiformisUnknownHLA DQ2*HLA DR3*HLA DQ8*HLADR7DERMATITIS HERPETIFORMIS (DH)EpidemiologyAge-20 to 40 years, M=F, Whites>Blacks/Asians EtiologyGenetics: HLA B8, DRw17 and DQw2External factors: Gluten containing diet like wheat, barley, oats and ryeAntigen: Gut epithelial antigen that cross reacts with skinAntibodies: IgA directed against gliadin and autoantigens like reticulin and endomysium PathogenesisGluten or its fragments are taken up by antigen presenting cells like lymphocytesActivation of cytokines and inflammatory cellsPlasma cells release lgA2 directed against gliadinCross-reacts with autoantigens of skin and gut like reticulin, endomyosiumClinical FeaturesIntensely pruriticMost vesicles have been scratched awayChronic recurrent grouped papulo vesicles, symmetricallyMost common on extensor surfaces, back of neck and sacrum, buttocksAssociated with gluten-sensitive enteropathyDiagnosisTzanck smear: Plenty of neutrophilsHistopathology: Neutrophilic microabscesses at the tips of dermal papilla with sub-epidermal vesicleImmunopathology: Clinically normal skin on forearm or buttock shows granular IgA deposits in the dermal papilla.TreatmentStrict gluten free dietSystemic steroids not the mainstay of therapyDapsone 100-200 mg/daySulphapyridine 1.5 g/dayTetracycline with nicotinamideColchicine when the above drugs are contraindicated
HLA DR4
HLA DQ2 and HLA DQ8
HLACW6
HLADR2
Papulosquamous Disorders