Early-onset group B streptococcal infection after a combined maternal and neonatal group B streptococcal chemoprophylaxis strategy.
OBJECTIVE
In January 1995, a combined maternal and neonatal protocol for prevention of early-onset group B streptococcal (GBS) infection was implemented that consisted of a risk factor-based approach for maternal intrapartum chemoprophylaxis using ampicillin combined with a single intramuscular dose of penicillin given to all newborns within 1 hour of delivery. The objective of this study was to review the cases of early-onset GBS infections that occurred from 1995 to 1999 to identify factors associated with their continued occurrence despite implementation of a GBS chemoprophylaxis protocol.


METHODS
Infants <or=72 hours of age with early-onset GBS infection born at Parkland Memorial Hospital in Dallas from January 1995 to December 1999 were identified through a prospective laboratory-based surveillance system. Maternal and infant medical records were reviewed for clinical and demographic data.


RESULTS
There were 32 cases (0.47/1000 live births) of early-onset GBS infection for the 5-year period. This represented a 76% reduction compared with the rate from 1986 to 1994 (1.95/1000), when there was no protocol for GBS chemoprophylaxis. Thirteen cases (41%) did not have any identifiable maternal risk factor. Of the 19 cases (59%) with risk factors, maternal intrapartum fever was the most frequent (15 [79%]), followed by prematurity (6 [32%]) and prolonged rupture of membranes (6 [32%]). Among the 19 mothers with risk factors, 15 (79%) mothers received intrapartum chemoprophylaxis, and 12 (80%) of the 15 mothers had intrapartum fever. Only 33% of mothers with risk factors received >or=2 doses of intrapartum chemoprophylaxis, and among those with intrapartum fever, 25% received >or=2 doses. None of the 32 infants with early-onset GBS infection received the combination of intrapartum ampicillin and postnatal penicillin.


CONCLUSIONS
A combined obstetric and neonatal chemoprophylaxis protocol significantly reduced early-onset GBS infection. Maternal intrapartum fever was the most frequent risk factor associated with failure of chemoprophylaxis.
Velaphi
Sithembiso
S
Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas, 75390-9063, USA.
Siegel
Jane D
JD
Wendel
George D
GD
Cushion
Nancy
N
Eid
Walid M
WM
Sánchez
Pablo J
PJ
D000667:Ampicillin / Q000008:administration & dosage*; D019072:Antibiotic Prophylaxis / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005334:Fever / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control; D010406:Penicillins / Q000008:administration & dosage*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D018805:Sepsis / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D012720:Severity of Illness Index; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D013292:Streptococcus agalactiae; D011795:Surveys and Questionnaires; D017211:Treatment Failure
D010406:Penicillins; D000667:Ampicillin