[Plantar hidradenitis].

INTRODUCTION

Plantar hidradenitis, one of several possible causes of painful papulo-nodular lesions of the foot in children and young adults, was recently described as the presence of characteristic lesions of the eccrine sweat glands.

CASE REPORT

A 15-year-old boy consulted for a sudden-onset painful eruption on the sole of the right foot. Physical examination revealed papulo-nodular erythromato-violet infiltrated lesions located on the anterior part of the right planta. Histology examination showed dense neutrophil inflammatory infiltration predominating at the dermo-hypodermic junction around the eccrine sweat glands. The excretory ducts of the sweat glands were infiltrated but the secretory glomerulae were intact. A dense infiltration of venular thrombi without vasculitis was also seen. The lesion regressed with aspirin (8 days) and rest. No recurrence has been recorded after 18 months.

DISCUSSION

This clinical and histological presentation led to the diagnosis of plantar hidradenitis, confirming the disease entity. Former cases may have been described as trauma-induced plantar urticaria or plantar erythema nodosum. This diagnosis should be entertained in children or young adults with painful papulo-nodular eruptions of the soles. The histology examination should include the eccrine sweat glands.