The clinical spectrum of infections with viridans streptococci in bone marrow transplant patients

A retrospective review of 832 bone marrow transplant patients was performed to determine the clinical spectrum and risk factors for viridans streptococci infections. The incidence of viridans streptococci cultured from the blood and/or cerebrospinal fluid was 15% (123/832), occurring within 15 days of bone marrow transplant in 78% of patients, usually during profound neutropenia. Strep. mitis was the most frequent isolate (47%). Only 27% (33/123) of patients were symptomatic beyond fever, usually with neurologic, pulmonary, and/or cardiovascular manifestations. Ten (8%) of 123 culture positive patients developed a fulminant cardiorespiratory collapse, with a 60% mortality. One additional death occurred due to cerebritis. However, a time dependent covariate analysis found no significant difference in overall mortality (p = 0.30) or duration of hospitalization (p = 0.50) in patients with or without viridans streptococci infections. A multivariate analysis revealed that age less than 18 years (RR = 1.5, p = 0.04) and a primary diagnosis of acute lymphocytic leukemia (RR = 1.5, p = 0.07) were independent and significant risk factors for viridans streptococci infections. Sex, conditioning regimen, donor type, in vitro bone marrow treatment, and acute graft-versus-host disease were not significant. Viridans streptococci should be recognized as pathogens in bone marrow transplant patients which require appropriate antibiotics and aggressive supportive therapy.