B72-09 The Triple Threat: Unmasking Disseminated Blastomycosis After Post-viral Pneumonia in an Immunocompetent Host

Abstract Introduction Pulmonary infections with Blastomyces dermatitidis can range from asymptomatic nodules to life-threatening disseminated disease. Presented is a case of respiratory failure with disseminated blastomycosis post-Influenza-A bacterial pneumonia. Case Presented is a 61-year-old female with diabetes, coronary artery disease, hypertension and tobacco use admitted for acute hypoxic respiratory failure with post-influenza-A bacterial pneumonia. CT chest revealed right middle and lower lobe consolidations with scattered bilateral nodules and pleural effusions. Thoracentesis revealed lymphocytic exudative fluid without bacterial or fungal growth. Hypoxia progressed despite antibiotics and oseltamivir, requiring heated high-flow nasal cannula and ICU transfer. Antibiotics were broadened and workup for immunodeficiency and rheumatologic disease were unremarkable. Skin examination revealed diffuse violaceous umbilicated nodulocystic pustules. Repeat CT chest demonstrated improvement in consolidation but increasing and enlarging pulmonary nodules. Hence, fungal etiology was suspected and empiric itraconazole was initiated. Given high risk for bronchoscopy, noninvasive fungal evaluation revealed positivity for (1,3)-beta-D-glucan (175 pg/mL), serum blastomyces antigen and skin punch biopsy for blastomyces dermatitidis. The patient rapidly improved after initiation of itraconazole and subsequently discharged to long-term care with prolonged antifungals. Discussion Blastomyces is a dimorphic fungus with widespread manifestations across organ systems. Primary foci are pulmonary due to conidia inhalation, with more than 50% of cases mild and 7-15% progressing to acute respiratory distress syndrome. Cutaneous manifestations appear as irregular papulopustular or verrucous lesions, and bony involvement is common. Blastomycosis is generally more severe in the immunocompromised, although overall incidence is higher in immunocompetent hosts. Chest imaging characteristics are nonspecific and include consolidations, lymphadenopathy, nodules (seldom cavitary), pleural effusions, and interstitial or miliary disease. Diagnostic challenge and delay often occurs due to overlapping features with bacterial, viral or other fungal pneumonias, requiring high index of suspicion. While definitive diagnosis via culture requires time, alternatives in the acutely ill include staining, urine or serum blastomyces antigen, and markers such as (1,3)-beta-D-glucan. Suspicion should be raised, even in immunocompetent patients, when pneumonia progresses on broad spectrum antimicrobials, especially with the aforementioned findings. We speculate this case could represent emergence of asymptomatic or latent pulmonary Blastomycosis in the setting of influenza. Recognition was obscured until worsening hypoxia, diffuse pulmonary nodules and, critically, cutaneous manifestations prompted alternative diagnoses. In this atypical case, early recognition facilitated timely treatment which is critical to prevent morbidity and mortality associated with disseminated disease. This underscores the importance of maintaining suspicion for endemic mycoses, even in less typical presentations. This abstract is funded by: None