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Molecular analysis of viridans and nutritionally deficient (variant) streptococci causing sequential episodes of endocarditis in a patient.

D S Stein·C R Libertin
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Abstract

Clinical blood isolates from sequential episodes of endocarditis occurring over a six-month period of time in an addict were investigated. The pathogens were Streptococcus sanguis II, Streptococcus mitis, and a nutritionally deficient (variant) streptococcus. The authors determined the DNA relatedness of these isolates by antibiograms, plasmid profiles, chromosomal endonuclease restriction digestions, and dot blot DNA-DNA hybridization analyses. The S. sanguis II and nutritionally deficient streptococcal strain had similar antibiograms being resistant to penicillin; neither produced beta-lactamase. No plasmids were found. The restriction endonuclease chromosomal digestion patterns of these isolates were unique and epidemiologically unrelated to each other. Dot blot DNA-DNA hybridizations, using the nutritionally deficient streptococcal DNA as the probe, showed homology to the preceding clinical isolates, S. sanguis II and S. mitis, at 15.4% and 45.1% hybridization levels, respectively. The nutritionally deficient streptococcus was only 4.2% homologous to a S. mitis ATCC strain and another nutritionally deficient streptococci isolate. Therefore, this patient had endocarditis with three distinct streptococcal strains.

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AdultDNAEndocarditis, BacterialFemaleGenetic VariationHumansNucleic Acid HybridizationStreptococcal InfectionsStreptococcusCase ReportsJournal ArticleResearch Support, Non-U.S. Gov't

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D S Stein, C R Libertin. 1989. Molecular analysis of viridans and nutritionally deficient (variant) streptococci causing sequential episodes of endocarditis in a patient.. https://doi.org/10.1093/ajcp%2F91.5.620

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