Abstract

Background: Nocardia spp are Gram-positive aerobic microorganisms that belong to the Nocardiaceae family, that most frequently cause infections in immunocompromised individuals and that are uncommonly associated to surgical site infections, especially following orthopedic surgery. The authors present a case of nocardial infection following an elective knee video arthroscopy in an immunocompetent adult and empathize the importance of the etiological diagnosis and treatment of this infection.

Case presentation: A 37-year-old immunocompetent female presented with painful edema, increased temperature and redness in the right knee, with the formation of nodules and abscesses one year after being submitted to a video arthroscopic procedure. Laboratory findings showed normochromic and normocytic moderate anemia and an elevated erythrocyte sedimentation rate, and MRI showed dense fluid collections in the medial portion of the knee. Nocardia spp was retrieved from tissue samples, and the patient was successfully treated with meropenem and trimethoprim-sulfamethoxazole for twelve months.

Conclusion: This is a case report of nocardial infection following elective orthopedic surgery in an immunocompetent patient. Nocardia spp is not a frequent pathogen in such SSI’s, but should be considered whenever chronic or recurrent nodular skin lesions are present, not only in immunocompromised hosts.

Keywords: Nocardial infections; Surgical site infections; Orthopedic surgery; Sulfamethaoxazole