Case Presentation: A 31-year-old female with diabetes mellitus, history of IV drug use on methadone, and untreated HCV infection presented with shortness of breath for one week. She developed a cough productive of green sputum with associated shortness of breath, subjective fevers, chills, pleuritic chest pain, nausea, and vomiting. One day prior to symptoms starting, she used IV heroin, because she was unable to obtain her methadone from her clinical provider. The patient denied any other drug use and stated that her symptoms had been progressive. The day of presentation she had awoken unable to breathe, which prompted her to call EMS, who found her with a room air oxygen saturation of 60%.Her presenting vitals were HR 138 RR 37 T 35.7 C, and she had a 15L oxygen requirement. Initial labs showed a leukocytosis of 16.6, lactate of 3.4, creatinine 1.36, and blood glucose of 421. Chest X-ray showed consolidation of the right middle and lower lobes with associated pleural effusion. CT chest showed large right loculated pleural effusion and TEE was negative for endocarditis. Patient had a dental panorex, which revealed numerous dental caries. Vancomycin, zosyn, and insulin were given initially. She was admitted for sepsis and respiratory failure due to pneumonia. Blood cultures and HIV were negative. Her A1C was 15.8, and initial pleural fluid sampling showed straw colored and opaque fluid. Fluid analysis showed glucose of 5, LDH <3, protein <2, and pH <6.8.Initial pleural fluid cultures grew gram-positive rods with “bead-like” appearance. She was treated with multiple broad spectrum antibiotics including zosyn, meropenem, TMP/SMX, and azithromycin before speciation could be finalized due to concern for resistant organisms and nocardia. Pulmonology placed a chest tube for tPA/dornase treatment. CT surgery was consulted due to concern for persistent air leak. They continued tPA/dornase due to patient preference for non-surgical management. Daily chest radiographs showed improvement in aeration and decrease in the size of the empyema. Pleural cultures eventually confirmed lactobacillus speciation. After the patient consented, a video-assisted thoracoscopic decortication was performed without complication. All surgical samples grew lactobacillus. Final sensitivity of lactobacillus culture showed susceptibility to Unasyn. She was discharged with an 4 additional weeks of Unasyn therapy and CT surgery outpatient follow-up.
Discussion: Bacteria from the genus Lactobacillus are part of the natural microbiome of the human gastrointestinal and genitourinary tracts. Rarely thought of as pathogenic, they are often taken as a probiotic supplement to aid in digestive health. Although few published cases exist in the literature, lactobacillus can lead to pneumonia or empyema in susceptible patients. Suggested risk factors for development of lactobacillus infection include diabetes mellitus, dental caries, conditions predisposing to aspiration, or immune-compromised states.
Conclusions: In the case described, the patient had multiple risk factors for lactobacillus empyema including poorly controlled diabetes, poor dental health and injection drug use with associated aspiration risk. Gram stain of pleural fluid showed gram positive rods with a beadlike appearance and cultures eventually were finalized as lactobacillus.