Gingivitis and toothbrushes: potential roles in viridans streptococcal bacteraemia

We report a case of Streptococcus oralis bacteraemia in a paediatric neutropenic patient with acute myeloid leukaemia whose predominant form of oral compromise was severe gingivitis, rather than mucositis. By phenotypic and genotypic analyses, the strain of S. oralis from blood culture was indistinguishable from an isolate from his mouth, suggesting that gingivitis may have provided a portal of entry for viridans streptococci into the bloodstream. To improve the patient's oral and dental hygiene and reduce gingivitis, conventional disposable foam toothettes were substituted with a new soft toothbrush for use as part of the oral care protocol. As there are no guidelines regarding the frequency of replacement of toothbrushes used by immunocompromised patients, the brush was swabbed regularly and culture performed to detect microbial colonization. Viridans streptococci were cultured from the toothbrush after 2 weeks of use. Phenotypic, followed by genotypic analyses, demonstrated that a strain of S. oralis from the toothbrush was indistinguishable from the strain previously isolated from blood culture and mouth. Soft toothbrushes may be useful tools for maintaining oral hygiene in immunocompromised individuals. However the results of this study indicate that regular replacement is warranted, as the toothbrush itself may become colonized with the organisms responsible for bacteraemia.