Disseminated cutaneous nocardiosis mimicking cellulitis and erythema nodosum.

Infection with Nocardia asteroides is a rare, life-threatening infection, which is most commonly encountered in immunocompromised patients. Cutaneous involvement is usually seen with disseminated infection but may also occur as primary cutaneous nocardiosis. We present a case of an immunocompromised patient who presented with cellulitis of the right hand and disseminated subcutaneous nodules of the lower extremities resembling erythema nodosum. Cultures from both a skin biopsy of a subcutaneous nodule on the leg as well as a surgical specimen from the debridement of her hand grew Nocardia asteroides. The patient was treated successfully with trimethoprim-sulfamethoxazole. This case likely represents primary cutaneous nocardiosis with secondary dissemination, which has been rarely reported. It also emphasizes that nocardial infection should be considered in the differential diagnosis of lesions suggestive of cellulitis or erythema nodosum in the severely immunocompromised patient.