[Primary cutaneous aspergillosis in an immunocompetent farmworker]

Aspergillosis is an uncommon fungal infection in which primary cutaneous sites are very rare. Most cases occur in immunodepressed patients and are disseminated in the blood. We report a case of primary cutaneous aspergillosis in a 37-year-old immunocompetent farmworker presenting as a kerion-like lesion.

A 37-year-old farmworker presented erythematous and nodular lesions of the face. These lesions were not associated with any general symptoms and failed to respond to antibiotic treatment. Histological examination of a skin biopsy sample showed a granulomatous reaction in the dermis associated with an extensive neutrophilic infiltrate. PAS staining revealed the presence of right-angled branched hyphae with conidia. Aspergillus fumigatus was isolated and identified in cultures. Clinical and biological examinations did not reveal any systemic localisation of aspergillosis, ruling out the hypothesis of blood dissemination. This primary cutaneous infection occurred in an immunocompetent patient, in whom laboratory tests ruled out any underlying immunosuppression. Systemic antifungal treatment with voriconazole led to complete resolution.

Reports in the literature of primary cutaneous aspergillosis in immunocompetent patients are extremely rare. Clinical lesions may comprise often painful weeping or necrotic macules or papules or subcutaneous nodules that can progress towards abscess or necrosis. The semiological similarity between these lesions and kerions can lead to misdiagnosed cases and delayed treatment.