A70-07 Connecting the Dots: A Case Series on Miliary-pattern Lung Disease in a Border City in Southwestern United States

Abstract Introduction A miliary pattern on chest imaging is defined by innumerable, randomly distributed bilateral pulmonary nodules measuring 1-3 mm, reflecting hematogenous spread. In the southwestern United States, dust storms and arid conditions increase the risk of infection with endemic Coccidioides species, however, proximity to a tuberculosis (TB)-endemic region merits its consideration. Miliary opacities present a diagnostic challenge due to their broad differential. We report three cases from West Texas illustrating distinct etiologies of diffuse micronodular lung diseases. Case 1 A 55-year-old man with alcohol-related cirrhosis and type 2 diabetes mellitus presented with one-month of nonproductive cough, fatigue, anorexia, and unintentional 20-pound weight loss. He was born and raised in West Texas and reported prior outdoor work and recreational hiking. He was cachectic, febrile, and hypoxemic with rapid progression requiring emergent intubation and mechanical ventilation. Computed tomography (CT) revealed diffuse micronodules in a miliary pattern with lingular consolidation. Bronchoalveolar lavage and Karius testing detected Coccidioides immitis/posadasii. Amphotericin B was initiated. His course was complicated by subdural hematoma, renal and multiorgan failure; he passed away after his family chose comfort care. Case 2 An 89-year-old woman with end-stage renal disease and psoas abscess on outpatient antimicrobial therapy presented with fever, back pain, weakness, and weight loss. She had a remote history of immigration from a TB-endemic region. Workup revealed neutrophilic leukocytosis, elevated inflammatory markers and miliary micronodules on CT chest. QuantiFERON-TB Gold, blood cultures, and abscess cultures were negative. Magnetic resonance of the spine was consistent with epidural abscess. She deteriorated and ultimately succumbed following laminectomy with surgical drainage. Postmortem analysis of abscess fluid yielded acid-fast bacilli (AFB). Case 3 A 77-year-old man with alcohol-related cirrhosis, diabetes and untreated positive tuberculin skin test was admitted with fever, encephalopathy, and cachexia after a recent admission for pleural effusion managed with empiric antibiotics. Imaging revealed a moderate left pleural effusion. TB treatment was initiated after pleural fluid tested positive for AFB. Chest CT demonstrated a miliary pattern, with cavitation and tree-in-bud opacities suggestive of pulmonary TB. He underwent chest tube placement and intrapleural fibrinolytic therapy. Sputum and pleural cultures confirmed Mycobacterium tuberculosis. He was eventually discharged. Discussion These cases illustrate the diagnostic complexity and severity of miliary pattern lung disease. Two of our three patients did not survive. The broad differential diagnosis including infectious and noninfectious processes requires integration of risk factors, history, labs, serologies, microbiological studies, and tissue/fluid sampling. This abstract is funded by: None