Prevalence and mechanisms of erythromycin and clindamycin resistance in clinical isolates of beta-haemolytic streptococci of Lancefield groups A, B, C and G in Seville, Spain.
Susceptibility to erythromycin and clindamycin was determined in 860 consecutive clinical isolates of beta-haemolytic streptococci belonging to groups A (GAS, n = 134), B (GBS, n = 689), C (GCS, n = 19) and G (GGS, n = 18). Erythromycin resistance was 26.1% in GAS, 15.7% in GBS, 5.3% in GCS and 33.3% in GGS. The highest rate of clindamycin resistance (33.3%) was in GGS, followed by GBS (15.8%), GCS (15.8%) and GAS (5.2%). The M phenotype was predominant in GAS (80%), the constitutive MLS(B) phenotype was predominant in GBS (75%), and all GGS isolates showed the inducible MLS(B) phenotype. The uncommon erythromycin-susceptible and clindamycin-resistant phenotype was found in four GBS and two GCS isolates.
Merino Díaz
L
L
Servicio de Microbiología, Hospitales Universitarios, Virgen del Rocío, Sevilla, Spain.
Torres Sánchez
M J
MJ
Aznar Martín
J
J
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002981:Clindamycin / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D004917:Erythromycin / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008826:Microbial Sensitivity Tests; D013030:Spain; D013290:Streptococcal Infections / Q000382:microbiology; D013291:Streptococcus / Q000187:drug effects* / Q000302:isolation & purification; D025381:Streptogramin B / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D025381:Streptogramin B; D002981:Clindamycin; D004917:Erythromycin