Genotype and Phenotype Relationship in MLSB Resistance in Streptococcus Pyogenes and Streptococcus Agalactiae Isolated in Central Italy

• Published in: International journal of immunopathology and pharmacology Vol. 19; no. 4; pp. 889 - 895
• Main Authors: Santino, I., Scazzocchio, F., Berlutti, F., Cipriani, P., Oliva, B., Paola, F., Del Piano, M.
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.10.2006
• Subjects: Anti-Bacterial Agents - pharmacology; Base Sequence; DNA Primers; Drug Resistance, Microbial; Genotype; Italy; Phenotype; Streptococcus agalactiae - drug effects; Streptococcus agalactiae - genetics; Streptococcus agalactiae - isolation & purification; Streptococcus pyogenes - drug effects; Streptococcus pyogenes - genetics; Streptococcus pyogenes - isolation & purification; Italy; erm(B) and mef(A); erm(A); macrolide-resistant; S. pyogenes; S. agalactiae
• ISSN: 0394-6320; 2058-7384
• DOI: 10.1177/039463200601900418

The aim of this work is to study a correlation between phenotype and genotype in clinical isolates of erythromycin-resistant Streptococcus spp. Among the 25 erythromycin-resistant S. pyogenes, we detected six strains with iMLSB nine with cMLSB and two with M phenotypes. Among 14 erythromycin-resistant S. agalactiae, we detected five strains with iMLSB, seven with cMLSB and none with an M phenotype. Moreover, 8 S. pyogenes and 2 S. agalactiae showed a phenotype not matching the known ones described in literature, defining an “unknown phenotype”. Upon examination, the genetic profiles, erm(A), erm(B) and mef(A), of the clinical isolates did not easily correlate with a specific phenotype. Our findings highlighted that the whole matter of phenotypic diversity in macrolide-resistant S. pyogenes and S. agalactiae strains and the correlation with their genetic profiles should be submitted to a more careful analysis of phenotypic and genotypic characterization.