A Case of Nocardia kroppenstedtii Infection Successfully Treated With a Multidisciplinary Approach.

Nocardia species constitute a diverse group of microorganisms classified as aerobic actinomyces. Among these species, many have been implicated as causative agents of severe human infections, particularly in immunocompromised patients, affecting lungs, skin, and nervous system. Here, we described a rare species, identified as Nocardia kroppenstedtii, isolated at the Complex Operative Unit of Virology and Microbiology from the subxiphoid formation and pseudonodular formation in the left leg of a 69-year-old immunocompetent patient, who was hospitalized and treated at the Complex Operative Unit of Internal Medicine and Geriatrics of the University Hospital of Campania "Luigi Vanvitelli" in an antimicrobial diagnostic stewardship context. This rare pathogen was first isolated in 2014 from a bronchoalveolar lavage sample obtained from a lung transplant recipient. Since then, only five cases of clinical interest have been described in literature.