420 SPO Abstracts

443 PERIPARTUM BLOOD/SECRETION CONTACT LINKED TO VERTICAL TRANSMISSION OF HIV INFECTION. K. Kondurix, T. Jones, E. Moorex, D. Harrisonx, N. RoumayahX

, S. Bottoms, F. Cohenx. Dept. Pediatrics and Ob/Gyn, Wayne State Univ., Detroit MI OBJECTIVE: We analyzed the effect of intrapartum and postnatal events in vertical transmission of HIV infection. STUDY DESIGN: The records of 78 HIV-infected pregnant women and their infants delivering between 1985 and 1991 were evaluated. Infants were divided into two groups: infected (26) and non-infected (52). Factors analyzed included ruptured membranes, scalp electrode, fetal scalp sampling, episiotomy, vaginal bleeding prior to delivery, cesarean section, baby bath after 120 minutes, baby blood draw prior to bath, and whether HIV status of mother was known at time of delivery. Data were analyzed using multiway contingency table analysis. RESULTS: Membrane rupture >2 hours, vaginal bleeding, episiotomy, and fetal scalp sampling were associated with infant infection (p< 0.05). There appeared to be a trend for baby blood draw prior to bath (p < 0.07) and scalp electrode (p < 0.08) to be linked to infant infection. Cesarean section, time of baby bath, or whether maternal HIV status was known at time of delivery were not significantly associated with infant infection. CONCLUSION: Peripartum contact with maternal blood and secretions significantly increases the risk for vertical transmission of HIV infection; every effort should be made to minimize it.

444 RAPID DNA PROBE FOR GROUP B STREPTOCOCCUS. R. Welch, M. Jordan,x N. Tierney,X E. Horowitz,X W. LeBar.x

Dept Ob/Gyn, Providence Hospital/WSU, Southfield, MI. OBJECTIVE: Group B streptococci (GBS) is the most common life-threatening neonatal infection. Rapid screening of women for GBS during labor is currently unavailable. We evaluated the ability of a new, rapid DNA-probe (AccuProbetm

, GEN-Probe, San Diego) to detect maternal GBS colonization. STUDY DESIGN: Vaginal/rectal swabs were obtained at the first prenatal visit. Results of AccuProbe assay were compared with bacterial cultures. Colonization was classified as light (colonies present in only one quadrant of the culture plate), or heavy (growth in the second through fourth quadrants). Analysis was by Chi-Square test of proportions. RESULTS: Of the 232 women tested for GBS, 34 had positive vaginal/rectal cultures (14% prevalence). Compared with vaginal cultures, AccuProbe's overall sensitivity was 47%; specificity 92%. With heavy vaginal colonization alone, AccuProbe detected 75%, compared with 12% with light colonization. CONCLUSIONS: The AccuProbe appears to detect 3 out of 4 patients with heavy vaginal GBS colonization. While the risk of vertical transmission to the neonate is greatest with heavy GBS colonization, risk from light colonization is alsQ present. It appears that AccuProbe screening during labor will only partially reduce neonatal GBS risk.

January 1993 Am J Obstet Gyneco1

445 ANTENATAL ASSESSMENT OF GROUP B STREPTOCOCCUS PREVALENCE: IS SCREENING WORTHWHILE? G. Gilson, M. Wellhoner, M. Platt" L. Nimms" L. Volpicelli" L. Curet. Depts. Ob/Gyn and Microbiology, Univ. of New Mexico, Albuquerque, NM. OBJECTIVE: We investigated the prevalence of group B streptococcus (GBS) carriage in our obstetric population to assess whether carrier status might be predicted, and if knowledge of same would intluence peripartum management. STUDY DESIGN: Vaginal and rectal swabs for GBS from 352 early third trimester women were incubated in selective medium. GBS carriers were treated with intrapartum antibiotics if they had a high-risk condition. Characteristics of GBS (+) and (-) women were compared. RESULTS: The overall prevalence of GBS carriage in this population was 18.5%. Of the GBS (+) patients, rectal (R), vaginal (V) and both sites were (+) in 25%, 29%, and 46% respectively. There was no significant difference in age, parity, ethnicity, gestational age, birth weight, Apgars, c-section, amnionitis, preterm labor, PROM, endometritis, or neonatal sepsis between GBS( +) and (-) women. Six high-risk women received intrapartum antibiotics because of being unexpectantly GBS( +). CONCLUSIONS: I)Antenatal screening appears to be beneficial for timely recognition of infants at risk. 2)No patient characteristic studied is capable of predicting who will be GBS (+). 3)Use of selective medium and sampling from both (R) and (V) sites are crucial for carrier detection. 4)We recommend that GBS screening be incorporated into standard obstetric practice.

446 A RANDOMIZED, PROSPECTIVE TRIAL OF AMOXICILLIN VERSUS ERYTHROMYCIN FOR THE TREATMENT OF CHLAMYDIA IN PREGNANCY. N. Silverman. M. Hochman,x M. Sullivan,x M. Womack.x Dept. of Ob/Gyn, Jefferson Medical College, Philadelphia, P A. OBJECTIVE: The importance of treating maternal chlamydia infections prior to delivery, along with high reported rates of noncompliance with traditional erythromycin therapy, led us to evaluate the efficacy of amoxicillin as an alternate therapy, comparing its chlamydia cure rate and side-effect profile to that of erythromycin. STUDY DESIGN: In a randomized, prospective fashion, 39 pregnant women with chlamydia infection diagnosed by McCoy cell culture were assigned to receive either amoxicillin (AM) 500 mg, 3 times daily (20 patients) or erythromycin (ER) 500 mg, 4 times daily (19 patients) for 7 days. Patients' parmers received doxycycline. Compliance information was obtained via a standardized questionnaire. Patients with positive follow up cultures were crossed over into the alternate treatment arm and re­cultured at a later visit. Cure and side effect rates between the two treatment groups were compared by chi-square analysis and Fisher's exact test where appropriate. RESULTS: The initial cure rates were 83.3% (15/18) for the AM group and 82.4% (14/17) for ER, prior to crossover (p=O.71). Two patients in each group were lost to followup, while one patient stopped ER therapy due to side effects and was placed in the AM group. Overall cure rates after crossover were 85.7% (18/21) for AM and 85.0% (17/20) for ER (1""0.71). In the AM group, 14.3% of patients reported side effects compared to 35% treated with ER (p=O.24), though 5 ER-treated patients compared to none of those in the AM arm stopped therapy due to side effects (p=0.05). CONCLUSIONS: The preliminary data from this study suggest that amoxicillin offers a reasonable alternative to erythromycin for the treatment of chlamydia in pregnancy, on the basis of both cure rates and patient compliance.