TB or Not TB: Lung Nocardiosis, a Tuberculosis Mimicker.

Nocardia, a gram-positive bacterium found in soil and water, rarely causes infections in immunocompetent patients. Diagnosing and treating nocardiosis can be challenging due to its infrequency and the similarity of its symptoms to other diseases. We describe the case of a middle-aged male with a history of latent tuberculosis who presented with hemoptysis. Imaging revealed a persistent lung mass, and pathology and microbiology studies confirmed Nocardia infection. The patient was treated with antibiotics and discharged home. Pulmonary nocardiosis can mimic tuberculosis, fungal infections, or malignancies. Immunocompetent patients make up one-third of the cases. Diagnosis can be difficult, as the organism takes time to grow in culture, but molecular techniques and histology can aid in diagnosis. Treatment often involves a six- to 12-month course of trimethoprim-sulfamethoxazole (TMP-SMX). Prompt identification of the etiological agent is essential for effective treatment, especially for immunocompetent patients who may not exhibit typical risk factors.

Streptococcus anginosus Lung Abscess With Complicated Parapneumonic Empyema.

A 55-year-old female with hypertension presented to our facility with complicated pneumonia. She complained of progressively worsening shortness of breath and pleuritic chest pain. She was in her usual state of health except for an upper respiratory infection treated with oral antibiotics a month prior. At the presentation, she was febrile, tachycardic, and hypoxic on room air. A chest computed tomography (CT) showed near-complete opacification of the right lung, a cavitation with the fluid level in the right middle lobe, and moderate-to-large effusion. Broad-spectrum antibiotics were started. Sputum culture was later positive for methicillin-resistant Staphylococcus aureus, which prompted antibiotic de-escalation to vancomycin. A chest tube was placed into the right pleural space draining 700 mL of exudative fluid, which cultures grew Streptococcus anginosus group (SAG) bacteria. Due to persistent respiratory distress and residual effusion, right thoracotomy and decortication were performed. A right upper lobe abscess ruptured into the pleural space was noted during the procedure. Pathology revealed necrotic tissue, and the microbiological workup was negative. The patient clinically improved postoperatively and was discharged home with oral Linezolid.