D107-02 Coccidioides Infection in a Patient With Pulmonary Alveolar Proteinosis: A Rare Complication of an Uncommon Disease

Abstract Introduction Pulmonary alveolar proteinosis (PAP) is a rare disorder characterized by impaired surfactant clearance, leading to alveolar accumulation of surfactant lipoproteins1. Retrospective studies have shown an increased incidence of certain pulmonary infections in patients with PAP2. Here we detail a case of primary Coccidioides pneumonia in a patient with PAP. Case Presentation A 32-year-old man was diagnosed with PAP five years earlier when he presented with several months of productive cough and dyspnea. Computed tomography (CT) scan of the chest demonstrated septal thickening in a crazy-paving pattern (Panel A), and cytology from bronchoalveolar lavage (BAL) showed dense granular proteinaceous material compatible with PAP. The diagnosis was further confirmed by presence of antibodies against Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF). He was treated with whole lung lavage (WLL) and subsequently with inhaled recombinant GM-CSF. Two years later an episode of COVID-19 infection led to a flare of PAP. He was treated with dexamethasone, remdesivir, and repeat WLL.3 Current presentation was after he self-discontinued GM-CSF therapy approximately 12 months prior. He presented with 2-3 weeks of worsening productive cough, night sweats, and unintentional weight loss. He was febrile, hemodynamically stable and had no hypoxemia. CT scan of the chest demonstrated a cavitary lesion of the right upper lobe with surrounding dense consolidation and additional scattered ground-glass opacities throughout all lobes, and bulky mediastinal lymphadenopathy (Panel B). Bronchoscopy with BAL and EBUS/TBNA was performed. Lymph node aspiration identified Coccidioides immitis, which also grew on fungal culture from BAL. He received IV amphotericin B induction followed by a 24-week course of fluconazole. Follow-up CT scan showed resolution of the prior cavitary lesion and other radiographic changes (Panel C). He is currently maintained on inhaled GM-CSF on a weekly intermittent schedule. Discussion PAP patients are known to have an increased incidence of opportunistic pulmonary infections, most commonly Nocardia but also Mycobacterium, and fungal species. It is hypothesized that the increased risk of infection is due to the lack of neutrophil recruitment during infection as signaling from mature macrophages is essential for activating this part of the innate immune response. Our patient developed the Coccidioides infection soon after a trip to Northern Mexico where Coccidioides is endemic; he was not receiving treatment with GM-CSF at the time. Our case identifies another rare dimorphic fungal infection in this at-risk patient population. This abstract is funded by: None