B71-05 Not All Lung Mass Are Cancer, a Case of Pulmonary Nocardia

Abstract Introduction Nocardia is an aerobic gram-positive, branching actinomycetes found in soil and water. It most commonly affects immunosuppressed individuals. Case 61 year-old male with history of colon cancer s/p chemoradiation and untreated HIV presented with generalized weakness, progressive dyspnea, and decreased appetite. Labs were obtained that showed a CD4 count of 4 and a viral load of 30,600 in setting of ART non-adherence. The patient went into paroxysmal Atrial fibrillation with RVR thus CTA chest was performed to rule out a pulmonary embolism. Diagnostic imaging revealed right upper lobe lung mass with satellite nodular densities and right peritracheal adenopathy. Patient underwent diagnostic bronchoscopy with EBUS to determine neoplastic vs infectious etiology. BAL was found to be growing nocardia, and patient was started on imipenem and Trimethoprim-Sulfamethoxazole.Lymph node biopsy showed neutrophil predominant infiltrates but was negative for malignant cells.CT brain ruled out Nocardia brain abscess. Discussion This case reinforces the importance of considering nocardia in HIV patient presenting with pulmonary mass or persistent pneumonia unresponsive to routine antibiotics. Since our patient was a heavy smoker and lost followup for colon cancer, differential diagnosis for lung mass included secondary metastasis due to colon cancer. Early microbiologic confirmation through BAL is essential to guide therapy and prevent dissemination. Clinicians should maintain a high level of suspicion for nocardiosis in immunocompromised populations, as early recognition can be lifesaving. Conclusion Pulmonary nocardia is a rare diagnosis, and its clinical presentation is nonspecific. It should be considered in an immunosuppressed patient to start timely appropriate treatment. This abstract is funded by: none