Emerging trends in invasive and noninvasive isolates of Streptococcus agalactiaein a Latin American hospital: a 17-year study

Abstract

BackgroundStreptococcus agalactiae or group B Streptococcus (GBS) has been recognized as a lethal pathogen in neonates worldwide. S. agalactiae infections also severely affect pregnant women and immunosuppressed adults with substantial attributable morbidity and mortality. However, in Latin America, studies on the epidemiology and behaviour of S. agalactiae infections remain limited.MethodsTo better understand the behaviour of S. agalactiae infections in our region, we conducted a retrospective study to phenotypically describe S. agalactiae isolates collected in one of the largest hospitals in Colombia at two time periods: 1994–2001 and 2004–2012. The isolates were identified by biochemical analysis and tested for antimicrobial susceptibility.ResultsIn 1994–2001 a total of 201 S. agalactiae isolates were found in urine 38.3%, vaginal exudates 27.8%, soft tissue 12.9%, and blood 8.5%. Susceptibility to ampicillin or penicillin was 94% whereas resistance to erythromycin and clindamycin were 2.8% and 5.2% respectively. In total 46 culture-positive cases of invasive infections were reported, 11 (24%) in neonates and 35 (76%) in adults. In 2004–2012 a total of 671 isolates were found in urine 47.8%, vaginal exudates 32.6%, soft tissue 2.7% and blood 9%. Susceptibility rates to ampicillin and penicillin were 98% whereas resistance to erythromycin and clindamycin were 12.5% and 9.4%. A total of 95 severe infections were reported: 12 (12.6%) were in neonates, 5 (5.3%) in children and 78 (82.1%) in adults. Over the 17-year study period the averaged prevalence of invasive S. agalactiae isolates was 17.4%. The estimated incidence for neonatal infections was 1.34 per 1000 livebirths (0.99 × 1000 livebirths for early- onset disease and 0.35 × 1000 livebirths for late- onset disease) whereas for non-pregnant adults the estimated incidence was 0.75 × 1000 admissions.ConclusionsA remarkable increase in bloodstream infections in immunosuppressed adults and a shift to early neonatal S. agalactiae infections were seen over time. We also found an increase in S. agalactiae resistance to erythromycin and clindamycin during the study period, and the emergence of penicillin-nonsusceptible isolates. Our findings are consistent with the global trends described elsewhere, reinforcing the need for S. agalactiae control measures in our region.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2334-14-428) contains supplementary material, which is available to authorized users.

Vigilancia de la sensibilidad a penicilina en Streptococcus agalactiae recuperados de embarazadas entre las 35-37 semanas de gestación

“…Las diferencias encontradas con otros autores pueden deberse al origen de las cepas de SGB 0,047 µg estudiadas. Mientras que las incluidas en este trabajo son cepas colonizantes obtenidas de hisopos vagino-rectales de mujeres embarazadas con 35-37 semanas de su edad gestacional, no hospitalizadas; las otras investigaciones incluyen, además, aislamientos provenientes de esputo, sangre, infecciones de piel y partes blandas y cepas de origen no especificado, aisladas del ambiente hospitalario donde es más frecuente encontrar cepas que han adquirido mecanismos de resistencia (13,14,17,(27)(28)(29)(30)(31) . Estos resultados, obtenidos para la provincia de Misiones, continúan apoyando el uso de penicilina administrada intra-parto, en la prevención de la severa enfermedad neonatal y en el tratamiento de otras infecciones causadas por SGB, en pacientes que no presenten alergia a antimicrobianos beta-lactámicos.…”

Ceftaroline activity on certain respiratory tract and wound infection agents at the minimum inhibitory concentration level

“…Crespo-Ortiz et al reported in a 17-year retrospective study that resistance to S. agalactiae isolates was emerging in Colombia [13]. While no resistance to cefaclor and cefuroxime was noted with M. catharralis isolates during 1993-1994, Hsu et al reported 8.3% and 1.3% resistance, respectively, in their study.…”

Streptococcus agalactiae en adultos no gestantes. Análisis de 10 años en un Hospital Universitario

“…A lo largo de los últimos 25 años ha sido notable el incremento de las infecciones invasivas por S. agalactiae en adultos 11 . Este incremento podría estar relacionado con la mayor esperanza de vida de los adultos mayores con enfermedades crónicas debilitantes 12 , siendo éstas un factor predisponente para adquirir una infección por SGB, en especial en aquellos que padecen DBT o algún tipo de neoplasia 13,14 .…”