Abstract Background Neisseria meningitidis (N. meningitidis) is an uncommon cause of pleuropulmonary infection, accounting for 5-15% of cases. Most infections manifest as meningitis or meningococcemia with meningococcal pneumonia being the second most common manifestation of invasive meningococcal disease. In contrast, pleural empyema due to N. meningitidis is exceedingly rare, with only a few adult cases reported to date. Reported risk factors include hematologic malignancy, complement deficiency, and immunosuppressive therapy. In immunocompromised hosts, atypical presentations can delay recognition and treatment. We present a case of N. meningitidis empyema in a patient with relapsed multiple myeloma. Case Presentation A 55-year-old man with IgG κ multiple myeloma on teclistamab presented with three days of chest pain. He was afebrile, tachycardic, and tachypneic. Chest radiograph and CT angiogram were unremarkable. Pain was attributed to vertebral compression fractures, and he was discharged with analgesics. Four days later, he re-presented with worsening left chest wall pain and new hypoxemia requiring 2–3 L oxygen. Lab work revealed thrombocytopenia (32 × 10³/µL), transaminitis (AST/ALT ≈ 90 U/L), and indirect hyperbilirubinemia (total 2.0 mg/dL; indirect 1.3 mg/dL). CT angiogram again excluded pulmonary embolism but showed a small left pleural effusion.On hospital day 1, he developed hypotension requiring vasopressors. Empiric antibiotics (vancomycin, cefepime, metronidazole) were initiated. Chest imaging demonstrated progressive left-sided opacification. By day 2, respiratory distress worsened with complete white-out and mediastinal shift on chest imaging. A 14F pleural catheter was inserted and drained amber fluid with gram-negative cocci on gram stain. Both blood and pleural cultures later grew pan-sensitive N. meningitidis. Due to diminished drainage on hospital day 4, intrapleural tPA/dornase was administered, after which the effusion became serosanguinous with concern for intraparenchymal hemorrhage though hemoglobin remained stable. Serial imaging demonstrated interval improvement in aeration of the left lung and reduction in pleural fluid volume, and the catheter was removed on day 7. The patient improved on cefepime and was discharged on ceftriaxone 2grams daily for four weeks. Discussion We describe a rare case of N. meningitidis empyema in a patient on teclistamab therapy for multiple myeloma. This patient’s myeloma and B-cell–directed immunotherapy likely impaired humoral immunity, facilitating airway colonization, bacteremia, and pleural seeding. The atypical afebrile presentation and initially unremarkable imaging delayed recognition. Only a few cases of N. meningitidis empyema have been described, underscoring the importance of diagnostic suspicion for unusual pathogens in immunocompromised hosts as prompt culture acquisition and early targeted antibiotic therapy can be lifesaving. This abstract is funded by: None
Narayanan et al. (Fri,) studied this question.