Abstract

DELGADO-PICADO, Eugenia; SAENZ-SANCHEZ, Carmen  and  CALDERON-ZUNIGA, Alberto. Tasa de Colonización del Streptococcus Agalactiae en Gestantes y Neonatos, Hospital de las Mujeres Dr Adolfo Carit Eva. Rev. costarric. cienc. méd [online]. 2004, vol.25, n.1-2, pp.25-32. ISSN 0253-2948.

Since 1970, Streptococcus agalactiae or Group B Streptococcus (EGB), was added to the list of important germs due to its capacity to produce neonatal sepsis, infections in pregnants and inmunocompromised adults. In our environment do not exist data about their incidence. Its detection in pregnant women before the delivery is fundamental in order to prevent the vertical transmission to the newborns. This investigation has as objectives: estimate the rates of colonization in newborn and pregnants in different anatomical sites, and also urge Doctors and Microbiologists to take consciousness of its isolation and clinical importance. Since June 16^th 2002 until March 15^th 2004, in the Hospital de Las Mujeres, 2952 urine cultures, 667 blood cultures, 383 vaginal cultures in different gestacional ages, 53 cultures of surgical wounds and 7 cultures of amniotic fluid were analyzed. Conventional methods for the isolation of facultative aerobic and anaerobic bacteria were used; the identification and antimicrobial susceptibility test were carried out by Microscan automatized method. EGB was isolated in 43 occasions, 95.3% (41 cases) in Obstetrics and 4.7% in Neonatology, 5.4% (22 cases) in urinary tract, 3.7% (14 cases) in vaginal tract, 5.7% (3 cases) in skin and soft tissues, 28.5% (2 cases) in amniotic fluid, and 0.3% (2 cases) in blood (1.7 newborns/10.000 live births). The low incidence in vaginal cultures was due to the non use of additional culture media that can detect the microorganism in small amounts. The screening cultures were not taking on to 35-37 weeks of gestation; neither was it taken without especulum from the entrance from the vagina and/or anorectum zone. The incidence in urine tract would increase if EGB were reported > 10.000 UFC/ml in blood media. This is important because its presence in urine implies high density of vaginal tract colonization. The so low incidence of neonatal infection implied the presence of few virulent germs

Keywords : Streptococcus agalactiae; Group B Streptococcus; perinatal infection; neonatal sepsis.