Neutrophilic eccrine hidradenitis secondary to infection with Serratia marcescens

Neutrophilic eccrine hidradenitis (NEH) is a rare dermatosis which usually develops after administration of chemotherapeutic treatments. An infective origin is exceptional. We report a patient, previously operated on for ependymoma, who presented with an eruption typical of NEH even though he had not received chemotherapy. Culture of a skin biopsy revealed Serratia marcescens. The dermatosis improved after antibiotic therapy but recurred twice and culture again isolated S. marcescens; electron microscopy revealed cytoplasmic inclusions within neutrophils, suggestive of bacteria. The disease improved every time with appropriate antibiotic therapy. An infective aetiology for NEH is rare: three such cases have been reported, of which one was due to S. marcescens. The originality of our case is the recurrence of the disease on three occasions with the same bacterium isolated on each occasion, with disease remission after antibiotic therapy. This case confirms that infections may be a possible cause of NEH and underlines the necessity to search for infective agents, especially in patients immunocompromised by haematopoietic malignancies and/or chemotherapeutic treatments.