Empyema caused by Actinomyces odontolyticus: A case report.

Rationale: Actinomyces odontolyticus causes a rare, chronic granulomatous infection that is frequently associated with immunocompromised states. A odontolyticus can cause infection in multiple organs, but empyema is rare.

Patient Concerns: We report a case of empyema caused by A odontolyticus. The patient was a 64-year-old man. He was admitted to the hospital with a 5-day history of fever and dyspnea. He had caries and sequelae of cerebral apoplexy.

Diagnoses: Metagenome next generation sequencing of pleural effusion was positive for A odontolyticus. Pathogen was identified by biphasic culture of pleural effusion fluid.

Interventions: According to the drug sensitivity test, linezolid 0.6 g twice daily and clindamycin 0.6 g 3 times a day were administered intravenously. Thoracic drainage was initially performed, but the drainage was not sufficient. Medical thoracoscopy was performed to fully drain the pleural effusion.

Outcomes: After anti-infection and medical thoracoscopic therapy, the symptoms of this patient improved.

Lessons: Microbial metagenome sequencing can find pathogens that are difficult to culture by traditional methods. Adequate drainage was the key to the treatment of empyema. Medical thoracoscopy was recommended to remove the pleural effusion and spoilage when thoracic drainage is difficult. The common clinical features of A odontolyticus include a mass or swelling, abdominal disease, dental disease, and subcutaneous abscesses. Microbial metagenome sequencing can find pathogens that are difficult to culture by traditional methods. Adequate drainage was the key to the treatment of empyema. Medical thoracoscopy was recommended to remove the pleural effusion and spoilage when thoracic drainage is difficult.