INVESTIGADORES
MOLLERACH Marta Eugenia
congresos y reuniones científicas
Título:
First isolation of Streptococcus agalactiae with reduced susceptibility to penicillin in Argentina.
Autor/es:
VIDAL P; BERTOLINI P; FLORES G; ARIAS B; BONOFIGLIO L; MOLLERACH M; LOPARDO H
Lugar:
Buenos Aires
Reunión:
Simposio; XIX Lancefield International Symposium on Streptococci & Streptococcal Diseases; 2014
Institución organizadora:
Lancefield Society
Resumen:
Introduction: Reduced susceptibility to penicillin (RSP) has already been described in Canada, USA, France, China and Japan. It was found that altered PBP, especially PBP2X makes a major contribution to the reduction of group B streptococcus (GBS) susceptibility to beta-lactams. Objective: to highlight the first isolation of a GBS with (RSP) in Argentina. Materials and methods: For urine cultures chocolate agar and CLED agar plates were used. Antimicrobial susceptibility tests were performed by the disk diffusion method, the Etest, and, only for penicillin, the broth dilution method following CLSI recommendations. Serotype was determined using a PCR method as was described and confirmed by sequencing. Case report: It was a diabetic 59 y-o patient with a history of hypertension and hypercholesterolemia. A prostatic adenoma was diagnosed and because an acute orchiepididymitis he received ciprofloxacin (500mg/d) during 28 days. Before the chirurgic intervention a urine culture yielded > 100000 CFU/ml of GBS as a unique organism. This strain was serotype V. It was resistant to erythromycin, levofloxacin, ofloxacin and ciprofloxacin, intermediately susceptible to penicillin (MIC=0.5mg/L) but susceptible to ceftriaxone (MIC =0.032 mg/L. One week later, in a new urine culture, the same result was obtained. In this instance, the patient was treated with ceftriaxone during 10 days and control urine cultures became negative. Discussion: The isolation of GBS with RSP has been especially reported in Japan since the last ten years. They were sporadically found in other countries but to the best of our knowledge this is the first isolation of this kind in South America. We feel that they may be overlooked taking into account that penicillin disk diffusion test appears not to be a good screening method. Conclusion: The first GBS with RSP was found in Argentina. Although clinical impact is not yet clearly defined, we highlight this finding because we think it would be a growing and more extended phenomenon, probably not detected by current susceptibility tests.