Unveiling the Complexity of Nocardia Septic Arthritis in an Immunocompromised Patient: A Case Report

Abstract

Background: Nocardiosis is the systemic manifestation of Nocardia infection, often found in immunocompromised individuals. Nocardia are transmitted via inhalation or skin wounds, disseminating hematogenously to organs and rarely, joints. We present a patient with immunosuppression who developed gout of the knee with superimposed Nocardial septic arthritis and a possible subsequent systemic infection.

Case presentation: A 74-year-old man presented with left lower extremity swelling and pain. He was taking immunosuppressive medication for antineutrophilic cytoplasmic antibody-positive vasculitis. A week prior, an arthrocentesis test was positive for gout. He received prednisone without improvement. A repeat arthrocentesis was positive for Nocardia farcinica septic arthritis. Chest imaging showed subpleural nodules. After failed antibiotics, a susceptibilities test yielded results that favored linezolid. The patient exhibited acute anemia from hematomas intramuscularly above the infection, which resolved with transfusions. Immunosuppression was stopped, and the patient recovered appropriately after the correct antibiotics were administered.

Conclusion: This case involves septic arthritis with possible pulmonary nodule involvement, showcasing the complexity of infections in immunocompromised individuals. Clinicians should maintain adequate suspicion for an infectious cause of arthritis in patients with immunosuppression. In our case, the hematomas are a curious finding, without known etiology. The question of when and how to reintroduce immunosuppressive agents while preventing the recurrence of nocardiosis remains a complex consideration.

Keywords: Nocardia; Nocardia infections; arthritis; case reports; gout; immunosuppression therapy; infectious.

Figure 1

The CT chest scans showed subpleural nodules, potentially related to nocardiosis.