Cutaneous nocardiosis

Nocardiosis is a rare infection, potentially severe when the diagnosis is delayed and/or the response to treatment is ineffective because of multidrug resistance. The number of patients suffering from nocardiosis is constantly rising worldwide, and especially the occurrence among immunocompetent patients is a matter of concern. Surgical site infections, although rare, should be considered among risks factors. Skin manifestations are often the first signs of the infection, both for direct inoculum (primary cutaneous infection) or disseminated disease. Clinicians might be misguided from the variable, unspecific, polymorphous skin eruptions, simulating more common diseases. Especially in the immune suppressed patients symptoms might evoke the same disease for which the patient is under treatment. The dermatologist’s expertise and high level of suspicion are crucial to settle the extensive differential diagnosis, cooperating with the pathologist, and microbiologist to find out the causative organism. Molecular methods of identification could improve diagnosis and the chances of survival, but are not routinely performed in many laboratories.