Abstract Community acquired pneumonia (CAP), the most common infectious etiology for hospitalization in U.S. adults, is most often secondary to Streptococcus (S.) pneumoniae. Cavitation is a rare complication of pneumonia due to S. pneumoniae in adults, more commonly seen with Staphylococcus aureus or fungal pathogens. One case series of adults with S. pneumoniae found necrotizing changes, including cavitations and abscesses, in only 6.6% of chest images. We present two cases of cavitary S. pneumoniae. A 36-year-old female with systemic lupus erythematosus and renal transplant was transferred for bilateral lung consolidations. She reported two weeks of dry cough and travel to the Midwestern and Southern United States, Canada, and Jamaica. Vital signs were normal on room air. Laboratory studies revealed white blood cell count 25 K/uL, CRP 31 mg/dL, and procalcitonin 0.67 ng/mL. Blood and sputum cultures remained negative. CT chest without contrast showed large cavitary consolidations in the left upper lobe and a thick-walled cavity with an air-fluid level in the lingula (Images 1, 2). Vancomycin, cefepime, azithromycin, and isavuconazonium were initiated. Flexible bronchoscopy with bronchoalveolar lavage (BAL) revealed thick, white, adherent secretions. A pneumonia polymerase chain reaction (PCR) panel of the BAL fluid was positive for S. pneumoniae and parainfluenza. A serum microbial cell free DNA test (Karius, Inc. laboratory) was sent. Patient improved to baseline health and, three weeks after discharge, Karius test found 103,541 molecules/100 nanoliters of S. pneumoniae DNA fragments.A 58-year-old female with history of psychosis and substance abuse was transferred for respiratory failure in the setting of bilateral lung consolidations and heart block secondary to endocarditis. Preceding history was limited. Patient arrived intubated/mechanically ventilated and intermittently paced via transvenous pacer. She was afebrile. Laboratory studies found no leukocytosis and procalcitonin 2.78 ng/mL. Sputum cultures were positive for candida. Blood cultures remained negative. CT chest without contrast revealed bilateral cavitary consolidations with a loculated right middle lobe abscess (Images 3, 4). Vancomycin and piperacillin-tazobactam were initiated. Flexible bronchoscopy with BAL revealed small, thick, brown secretions. A pneumonia PCR panel of the BAL fluid was positive for S. pneumoniae. Patient was extubated after seven days and continued to improve. Cavitary S. pneumoniae is likely underdiagnosed. These cases, the first in an immunocompromised and the second in an immunocompetent host, highlight that molecular diagnostics, including PCR and microbial cfDNA testing, can identify this entity even when imaging is nonclassical and cultures are negative. This abstract is funded by: None
Rubel et al. (2026) studied this question.