Streptococcus salivarius pneumonia with pulmonary nocardiosis in a rheumatoid arthritis patient treated with immunosuppressants / 대한내과학회지

ABSTRACT

Streptococcus salivarius is a Gram-positive organism that belongs to the viridians group of streptococci. It is a relatively non-virulent bacterium that is part of the normal flora. It is rarely isolated from blood and is usually considered a contaminant. Nevertheless, S. salivarius may cause life-threatening infections, especially in immunocompromised hosts. There have been relatively few reports of S. salivarius pneumonia. Nocardiosis is also a rare opportunistic infection. Pulmonary nocardiosis is difficult to diagnose and, consequently, the diagnosis is often delayed. We report an unusual presentation with multiple pulmonary mass-like consolidations caused by a mixed infection of S. salivarius and Nocardia sp. in a 58-year-old man with rheumatoid arthritis who was taking oral corticosteroid, methotrexate, and leflunomide. The patient's symptoms and radiographic findings improved after six weeks of antibiotic therapy