Joan A. Regan

Antibiotic susceptibility profiles for group B streptococci isolated from neonates, 1995-1998

Antibiotic susceptibility profiles were analyzed for 119 invasive and 227 colonizing strains of group B streptococci isolated from neonates at 6 US academic centers. All strains were susceptible to penicillin, vancomycin, chloramphenicol, and cefotaxime. The rate of resistance to erythromycin was 20.2% and to clindamycin was 6.9%. Resistance to erythromycin increased in 1997. Type V strains were more resistant to erythromycin than were type Ia (P=.003) and type Ib (P=.004) strains and were more resistant to clindamycin than were type Ia (P<.001), type Ib (P=.01), and type III (P=.001) strains. Resistance rates varied with geographic region: in California, there were high rates of resistance to erythromycin and clindamycin (32% and 12%, respectively), and low rates in Florida (8.5% and 2.1%, respectively). Penicillin continues to be the drug of choice for treatment of group B streptococcus infection. For women who are penicillin intolerant, however, the selection of an alternative antibiotic should be guided by contemporary resistance patterns observed in that region.

Level of Maternal IgG Anti-Group B Streptococcus Type III Antibody Correlated with Protection of Neonates against Early-Onset Disease Caused by This Pathogen

The present study estimates the level of maternal immunoglobulin (Ig) G anti-group B streptococcus (GBS) type III required to protect neonates against early-onset disease (EOD) caused by this pathogen. Levels of maternal serum IgG anti-GBS type III, measured by enzyme-linked immunosorbent assay, in 26 case patients (neonates with EOD caused by GBS type III) and 143 matched control subjects (neonates colonized by GBS type III who did not develop EOD) of > or = 34 weeks gestation were compared. The probability of EOD decreased with increasing levels of maternal IgG anti-GBS type III (P = .01). Neonates whose mothers had > or = 10 microg/mL IgG anti-GBS type III had a 91% lower risk for EOD, compared with those whose mothers had levels of < 2 microg/mL. A vaccine that induces IgG anti-GBS type III levels of > or = 10 microg/mL in mothers can be predicted to offer a significant degree of protection against EOD caused by this pathogen.

Level of Maternal Antibody Required to Protect Neonates against Early-Onset Disease Caused by Group B Streptococcus Type Ia: A Multicenter, Seroepidemiology Study

Because of the difficulty of conducting efficacy trials of vaccines against group B streptococcus (GBS), the licensure of these vaccines may have to rely on studies that measure vaccine-induced antibody levels that correlate with protection. This study estimates the level of maternal antibody required to protect neonates against early-onset disease (EOD) caused by GBS type Ia. Levels of maternal serum IgG GBS Ia antibodies, measured by ELISAs in 45 case patients (neonates with EOD caused by GBS Ia) and in 319 control subjects (neonates colonized by GBS Ia but without EOD) born at > or =34 weeks gestation were compared. The probability of developing EOD declined with increasing maternal levels of IgG GBS Ia antibody (P = .03). Neonates whose mothers had levels of IgG GBS Ia antibody > or =5 microg/mL had an 88% lower risk (95% confidence interval, 7%-98%) of developing type-specific EOD, compared with those whose mothers had levels < 0.5 microg/mL. A vaccine that induces IgG GBS Ia antibody levels > or =5 microg/mL in mothers can be predicted to confer a high degree of type-specific immunity to EOD to their infants.

Capsular Polysaccharide Types of Group B Streptococcal Isolates from Neonates with Early-Onset Systemic Infection

The distribution of serotypes of group B streptococci (GBS) isolated from 67 infants with early-onset sepsis are described. Case-infants were assembled from 13 hospitals across the United States from 15 July 1995 to 5 February 1997 through prospective active surveillance. The distribution of GBS serotypes was Ia, 40%; Ib, 9%; II, 6%; III, 27%; V, 15%; and nontypeable, 3%. Type V occurred more frequently in the northeast region (New York and New Jersey) than in other regions (29% vs. 9%, P = .06). Conversely, type III occurred significantly less frequently in the northeast region than other regions (10% vs. 35%, P = .04). GBS types Ia, III, and V accounted for 82% of the isolates. This report supports previous observations about the emergence of GBS type V, but our data caution that conclusions about serotype distributions based on one geographic location or on a small number of patients may not be generally applicable. Continued monitoring seems necessary for the design of a GBS vaccine.

Vertical transmission of Ureaplasma urealyticum from mothers to preterm infants

Ureaplasma urealyticum is a common component of the vaginal flora during pregnancy. Although colonization of low birth weight infants with U. urealyticum occurs frequently, the actual rate of vertical transmission of U. urealyticum in preterm infants has not been determined. Sixty-five preterm infants (<37 weeks of gestation) born to mothers colonized with U. urealyticum had eye, throat, vagina and rectum cultured for U. urealyticum at 1, 3 and 7 days of age and weekly thereafter for the first month of life while the infants remained in the hospital. Thirty-eight infants (58%) had at least one culture site positive for U. urealyticum (eye, 8%; throat, 37%; vagina, 54%; and rectum, 18%). Vertical transmission was not affected by method of delivery or duration of rupture of amniotic membranes. The rate of vertical transmission of U. urealyticum was higher among infants with birth weight less than 1000 g (89%) than among those with birth weight of 1000 g or greater (54%) (P = 0.07). Chronic lung disease developed in 9 of the 65 (14%) infants; 8 were colonized with U. urealyticum. The high rate of ureaplasmal colonization and chronic lung disease in infants less than 1000 g makes these infants a suitable target population for a clinical treatment trial to determine whether eradication of U. urealyticum would decrease the incidence of chronic lung disease.

Phylogenetic Lineages of Invasive and Colonizing Strains of Serotype III Group B Streptococci from Neonates: a Multicenter Prospective Study

ABSTRACT This study compares the phylogenetic lineages of invasive serotype III group B streptococci (GBS) to those of colonizing strains in order to determine lineages associated with invasive disease. Isolates from 29 infants with early-onset disease (EOD) and from 196 colonized infants, collected in a prospective, multicenter study, were assigned a sequence type (ST) by multilocus sequence typing. Overall, 54.5% of the isolates were in the ST-19 complex, and 40.4% were in the ST-17 complex. Invasive strains were more likely to be in the ST-17 complex than were colonizing strains (59% versus 38%, P = 0.03). After we adjusted for potential confounders, the ST-17 complex was more likely to be associated with EOD than were other lineages (odds ratio = 2.51, 95% confidence interval = 1.02 to 6.20). These data support the hypothesis that ST-17 complex GBS are more virulent than other serotype III GBS.

Vertical transmission of Ureaplasma urealyticum in full term infants

Ureaplasma urealyticum is a common inhabitant of the urogenital tract of pregnant women. Although colonization of newborn infants with U. urealyticum has been documented previously, the actual rate of vertical transmission has not been determined. Cervical cultures for U. urealyticum were performed on 1315 pregnant women on admission to the labor suite. A positive culture was found in 810 (62%). Eye, nasopharyngeal and/or throat, vaginal and rectal cultures were obtained in the first 5 days of life from 132 full term infants born to mothers colonized with U. urealyticum. Fifty-nine infants (45%) had at least one culture site positive for U. urealyticum (eye, 4%; nasopharynx 24%; throat, 16%; vagina, 53%; and rectum, 9%). None of the infants had evidence of disease caused by U. urealyticum during the nursery stay. Vertical transmission was not affected by the method of delivery. However, among the vaginally delivered infants, rupture of membranes greater than 1 hour correlated with an increased rate of vertical transmission of U. urealyticum (52%) compared with rupture of membranes less than or equal to 1 hour (22%) (P less than 0.05). Because vertical transmission of U. urealyticum occurs frequently, caution must be exercised when attributing disease to U. urealyticum based solely on positive cultures of mucosal surfaces.

Double-Blind Placebo-Controlled Treatment Trial of Chlamydia trachomatis Endocervical Infections in Pregnant Women.

Objective: The purpose of this study was to determine if treatment of pregnant women with Chlamydia trachomatis infection would lower the incidence of preterm delivery and/or low birth weight. Methods: Pregnant women between the 23rd and 29th weeks of gestation were randomized in double-blind fashion to receive either erythromycin 333 mg three times daily or an identical placebo. The trial continued until the end of the 35th week of gestation. Results: When the results were examined without regard to study site, erythromycin had little impact on reducing low birth weight (8% vs. 11%, P = 0.4) or preterm delivery (13% vs. 15%, P = 0.7). At the sites with high persistence of C. trachomatis in the placebo-treated women, low birth weight infants occurred in 9 (8%) of 114 erythromycin-treated and 18 (17%) of 105 placebo-treated women (P = 0.04) and delivery <37 weeks occurred in 15 (13%) of 115 erythromycin-treated and 18 (17%) of 105 placebo-treated women (P = 0.4). Conclusions: The results of this trial suggest that the risk of low birth weight can be decreased by giving erythromycin to some women with C. trachomatis. Due to the high clearance rate of C. trachomatis in the placebo group, these data do not provide unequivocal evidence that erythromycin use in all C. trachomatis-infected women prevents low birth weight.

Acquired coarctation of the aorta.

SummaryCoarctation of the aorta is usually caused by a congenital narrowing of the aorta. This report describes two children who developed hypertension secondary to an acquired coarctation of the aorta. In one patient the coarctation was temporally related to umbilical artery catheterization and was associated with thrombosis and aneurysmal dilatation of the aorta. In the second patient, the coarctation occurred after surgical aortotomy during the removal of an intrathoracic neuroblastoma. Patients who have interventional damage to the aorta should be periodically examined for the appearance of a coarctation. Although an acquired coarctation of the aorta is an infrequent complication of invasive or surgical procedures, it should be identified since it represents a remediable cause of hypertension in children.

Antibiotic Susceptibility of Invasive Group B Streptococci from Neonates with Early-Onset Disease - A Multi Center Study 1995-97

Antibiotic Susceptibility of Invasive Group B Streptococci from Neonates with Early-Onset Disease - A Multi Center Study 1995-97