Nocardia Bloodstream Infection: A Retrospective Clinical Analysis of Seven Cases in a Single Centre

Nocardiosis is a rare opportunistic infection caused by the Nocardia species. Nocardia bacteremia is a life-threatening presentation of disseminated nocardiosis that presents diagnostic and therapeutic challenges. We performed this retrospective analysis in a Chinese hospital from 2010 to 2019 to describe the characteristics of this rare bloodstream infection.

We searched the database of the real-time nosocomial infection surveillance system and identified patients whose blood cultures showed Nocardia bacteria growth. The medical records of these patients were extracted and analyzed by two independent researchers. The data included age, gender, complicating disease, duration from blood drawing to reporting, clinical signs and symptoms, blood routine and C-reactive protein results, radiological examinations, sites of involvement, antibiotic treatments, and outcomes.

Seven patients with Nocardia bacteremia were found. There were four male and three female patients, whose ages ranged from 41 to 75 years. Six (85.7%) patients had predisposing conditions and were administrated corticosteroids for various reasons before the identification of Nocardia infection. The most common symptom was fever (100%). Five patients presented with lung or skin involvement; meanwhile, three patients presented with brain involvement. One patient presented with pelvic and peritoneum involvement, respectively. The most common findings of chest CT imaging were consolidation, followed by nodules and cavitations. Trimethoprim/sulfamethoxazole was prescribed to all patients after the diagnosis of Nocardia bacteremia. Six patients recovered, and one patient ultimately died.

Nocardia bacteremia is a rare bloodstream infection that usually occurs in immunocompromised patients. Clinical manifestations of patients are nonspecific. It often causes multiple organ involvement, and early diagnosis and prompt aggressive interventions are important to improve the outcome of this disease.