Introduction: Capnocytophaga is commonly found in normal human oral flora, occasionally causing periodontal disease. Few cases of capnocytophaga empyema have been reported, typically in immunocompromised patients. There are no known established risk factors for capnocytophaga empyema due to its rare presentation. Early identification through culture is important as infection can lead to severe respiratory distress, septicemia, and shock, and carries a high mortality rate if left untreated. We present a case of a 56-year-old male, with no previous medical history who presented with shortness of breath and was found to have capnocytophaga empyema. 

Case Presentation: A 56-year-old Caucasian male with no known medical history aside from tobacco and alcohol dependence presented to the emergency department with cough, worsening shortness of breath and foul smelling sputum. Vitals showed heart rate of 138 bpm and oxygen saturation of 87% on noninvasive mechanical ventilation. Physical exam revealed poor oral dentition, bilateral lung crackles, severe respiratory distress, and jaundice. Labs showed leukocytosis, lactic acidosis, and elevated procalcitonin. Computed Tomography (CT) of the abdomen and pelvis revealed complex right pleural effusion, bilateral lower lobe and right middle lobe consolidations, and partially enhancing lesion in the right hepatic lobe. CT angiography of the chest confirmed pneumonia and a right hydropneumothorax possibly representing empyema. The patient was intubated for worsening respiratory status and started on empiric vancomycin, ceftriaxone and metronidazole for community acquired pneumonia complicated by possible empyema. A thoracostomy tube was placed and drained purulent, foul-smelling fluid. Pleural fluid analysis revealed an exudative process with cultures showing capnocytophaga species. Antibiotic therapy was deescalated to cefepime and metronidazole as identification and sensitivities were delayed due to innate microbiologic characteristics of the organism. 

Final Diagnosis: Capnocytophaga empyema 

Management/Outcome and Follow-up: The patient eventually improved and was subsequently extubated with removal of the chest tube. The patient was discharged with cefuroxime 500 mg orally twice daily for four weeks. The patient was seen in the outpatient setting with no complications at follow-up.

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