Two cases of palmar petechiae as a presentation of dermatitis herpetiformis

Abstract

Conflict of interest: none declared. Haemorrhagic palmoplantar lesions are a recognised presentation of childhood dermatitis herpetiformis (DH), with a few reported adult cases.1, 2 We report two cases of palmar petechiae as a presenting feature of adult DH. Patient 1 was a 34‐year‐old woman, who presented with an 18‐year history of a rash affecting her fingertips and toes, most prominent on her dominant hand and preceded by an itchy sensation. On physical examination, multiple petechial lesions were seen on her fingertips and toes (Fig. 1a), together with a small tense blister filled with serosanguinous fluid on the right hand. Screening for anti‐mitochondrial, anti‐smooth muscle, anti‐parietal cell, anti‐liver kidney microsomal antibodies, cytoplasmic antinuclear cytoplasmic antibodies (ANCA) perinuclear ANCA, thrombophilia and porphyria was negative. She had a weakly positive antinuclear antibody titre with a nucleolar pattern. Histological examination of a petechial lesion found disruption of the keratin layer with haemorrhage, intracorneal vesicle formation and red cell extravasation in the dermis with moderate oedema. Histological examination of a biopsy taken from the blister on the right hand revealed a subepidermal split with abundant neutrophils, lymphocytes and histiocytes. Effacement of the dermal papillae was noted (Fig. 1b). Direct immunofluorescence of perilesional skin showed fibrillar deposits of IgA and fibrinogen within the dermal papillae (Fig. 1c). Anti‐endomysial IgA antibodies were negative on indirect immunofluorescence, but duodenal biopsies confirmed subtotal villous atrophy (Fig. 1d).