Granular IgA deposit at dermal papilla are found in: (LQ)
|B||IgA disease of childhood|
1. IgA deposits in dermis are seen in the following conditions:
2. Granular deposits (at tips of dermal papilla) àDermatitis Herpetiformis (option A)
3. Linear deposits à CBDC and Linear IgA dermatoses of Adults (option B)….
4. Dermatitis Herpetiformis (DH)
1. Subclinical gluten sensitive enteropathy. (in ~ all)
2. HLA – B8 / DRw3 & HLA DQW2 haplotype (~90%)
3. Increased incidence of thyroid abnormalities, achlorhydria, atrophic gastritis, and Anti gastric parietal cell antibodies.
4. As in patients with celiac ds., dietary gluten sensitivity in DH is associated with IgA endomysial autoantibodies that target tissue transglutaminase.
5. IgA autoantibodies against epidermal transglutaminase & granular deposits of IgA in papillary dermis.
1. Intensely pruritic, papulovesicular skin ds, characterized by lesions symmetrically distributed over extensor surfaces (i.e. elbows, knees, buttocks, back scalp & posterior neck) (important).
2. Primary lesion is a papule, papulovesicle or urticarial plaque. Because pruritus is prominent, patients may present with excoriation & crusted papules with no observable primary lesion.
3. May present at any age including childhood; but 2nd – 4th decades are most commonly involved.
Diagnosis & Treatment:
1. Biopsy reveal subepidermal blister with neutrophils in dermal papillae.
2. Diagnosis is confirmed by direct immunofluorescence microscopy of normal appearing perilesional skin, by demonstration of granular deposits of IgA (with or without complements) in papillary dermis and along the epidermal basement membrane zone.
3. IgA deposits in skin are unaffected by control of disease with medication dapsone; but decrease or disappear in patients maintained on long periods on a strict gluten – free diet.
4. Herpes Gestation(option C):
a. Autoimmune vesiculobullous disorder seen in pregnancy
b. Linear IgG deposits in BMZ (base membrane zone)
5. Bullous Pemphigoid (option D):
a. Linear IgG deposits in BMZ (base membrane zone)