Mara J. Dinsmoor

Risk Factors and Opportunities for Prevention of Early-onset Neonatal Sepsis: A Multicenter Case-Control Study

Background. Early-onset group B streptococcal (GBS) prevention efforts are based on targeted use of intrapartum antibiotic prophylaxis (IAP); applicability of these prevention efforts to infections caused by other organisms is not clear. Methods. Multicenter surveillance during 1995 to 1996 for culture-confirmed, early-onset sepsis in an aggregate of 52 406 births; matched case-control study of risk factors for GBS and other sepsis. Results. Early-onset disease occurred in 188 infants (3.5 cases per 1000 live births). GBS (1.4 cases per 1000 births) andEscherichia coli (0.6 cases per 1000 births) caused most infections. GBS sepsis less often occurred in preterm deliveries compared with other sepsis. Compared with gestation-matched controls without documented sepsis, GBS disease was associated with intrapartum fever (matched OR, 4.1; CI, 1.2–13.4) and frequent vaginal exams (matched OR, 2.9; CI, 1.1–8.0). An obstetric risk factor—preterm delivery, intrapartum fever, or membrane rupture ≥18 hours—was found in 49% of GBS cases and 79% of other sepsis. IAP had an adjusted efficacy of 68.2% against any early-onset sepsis. Ampicillin resistance was evident in 69% of E coliinfections. No deaths occurred among susceptible E coliinfections, whereas 41% of ampicillin-resistant E coliinfections were fatal. Ninety-one percent of infants who developed ampicillin-resistant E coli infections were preterm, and 59% of these infants were born to mothers who had received IAP. Conclusions. Either prenatal GBS screening or a risk-based strategy could potentially prevent a substantial portion of GBS cases. Sepsis caused by other organisms is more often a disease of prematurity. IAP seemed efficacious against early-onset sepsis. However, the severity of ampicillin-resistant E colisepsis and its occurrence after maternal antibiotics suggest caution regarding use of ampicillin instead of penicillin for GBS prophylaxis.

A randomized trial of intrapartum versus immediate postpartum treatment of women with intra-amniotic infection

&NA; A randomized trial of intrapartum versus postpartum antibiotic treatment of women with intra‐amniotic infection was conducted. Intra‐amniotic infection was treated with ampicillin and gentamicin during labor (at the time of diagnosis) in 26 women and immediately after umbilical cord clamping in 19 women. Intrapartum treatment led to a lower incidence of neonatal sepsis (0 versus 21%; P = .03) and a shorter neonatal hospital stay (3.8 versus 5.7 days; P = .02) when compared with postpartum treatment. There were no significant differences in the microbiologic results, the gestational age, or the birth weight between the groups. Intrapartum‐treated mothers had a shorter mean postpartum stay, a lower mean number of febrile days, and a lower mean peak postpartum temperature than did postpartum‐treated mothers; these differences were all statistically significant (P = .05). The treatment of clinical intra‐amniotic infection during labor results in improved outcome.

Red blood cell transfusion and cesarean section

OBJECTIVE Our objective was to determine the incidence of blood transfusion in patients delivered by cesarean section and to identify factors predictive of the need for transfusion. STUDY DESIGN A chart review was performed on cesarean patients receiving blood transfusion over a year at the Medical College of Virginia Hospital and an equal number of randomly selected cesarean patients. RESULTS Sixty-one (6.8%) patients received a packed red blood cell transfusion intraoperatively or postoperatively. Transfusion was associated with lower gestational ages, antepartum bleeding, arrest of descent, and longer postoperative stays. After stepwise logistic regression analysis, only antepartum bleeding and preoperative hemoglobin were significant independent predictors of the need for blood transfusion. CONCLUSION Transfusion with cesarean section is common and is associated with antepartum bleeding and other primarily intrapartum and unpredictable factors.

Perioperative antibiotic prophylaxis for nonlaboring cesarean delivery.

OBJECTIVE: To estimate the efficacy of antibiotic prophylaxis at the time of nonlaboring cesarean delivery in reducing postpartum infection-related complications. METHODS: We performed a secondary analysis of an observational study of cesarean deliveries performed at 13 centers from 1999–2000. Patients were included if they had cesarean delivery before labor, did not have intrapartum infection, and were not given antibiotics at delivery for reasons other than prophylaxis. The occurrence of postpartum endometritis, wound infection, and other, less common infection-related complications was compared between those who did and did not receive antibiotic prophylaxis. Results were adjusted for smoking, payer status, gestational age and body mass index at delivery, race, diabetes, antepartum infections, presence of anemia, operative time, type of cesarean delivery (primary or repeat), and center. RESULTS: Of the 9,432 women who met study criteria, the 6,006 (64%) who received antibiotic prophylaxis were younger, heavier at delivery, and were more likely to be African American, receive public insurance, and have diabetes. Patients who received antibiotic prophylaxis were less likely to develop postpartum endometritis (121 [2.0%] compared with 88 [2.6%], adjusted odds ratio [OR] 0.40, 95% confidence interval [CI] 0.28–0.59) or wound infection (31 [0.52%] compared with 33 [0.96%], adjusted OR 0.49, 95% CI 0.28–0.86). CONCLUSION: Antibiotic prophylaxis at the time of nonlaboring cesarean delivery significantly reduces the risks of postpartum endometritis and wound infection. LEVEL OF EVIDENCE: III

In utero progression of mild fetal ventriculomegaly

To evaluate the progression in utero of mild isolated fetal ventriculomegaly (defined as a transverse diameter of the atrium of the lateral ventricle measuring between 10 and 15 mm), and to estimate the proportion of fetuses that normalize (diameter decreasing to less than 10 mm), stabilize (remaining between 10 and 15 mm), or progress to more severe ventriculomegaly (becoming greater than 15 mm).

Transmission of genital mycoplasmas from mother to neonate in women with prolonged membrane rupture

Colonization of the neonate with genital mycoplasmas occurs during passage through a colonized birth canal or in utero via contamination of the amniotic fluid. To define further the route of transmission we obtained cultures from the maternal vagina, the amniotic fluid and the neonatal pharynx in 131 mother-baby pairs. Sixty-six percent (33 of 50) of the corresponding amniotic fluids were colonized when the vagina was colonized with Mycoplasma hominis. When the amniotic fluid contained M. hominis, 26% (9 of 34) of the neonates were colonized. Sixty percent (66 of 110) of the corresponding amniotic fluids were colonized when the vagina was colonized with Ureaplasma urealyticum. When the amniotic fluid contained U. urealyticum, 32% (22 of 69) of the neonates were colonized. No neonates were colonized with M. hominis without prior colonization of both the vagina and the amniotic fluid. We conclude that colonization of the amniotic fluid is an important intermediate step in colonization of the neonate with genital mycoplasmas.

Risk Factors and Opportunities for Prevention of Early-Onset Neonatal Sepsis: A Multicenter Case-Control Study

BACKGROUND Early-onset group B streptococcal (GBS) prevention efforts are based on targeted use of intrapartum antibiotic prophylaxis (IAP); applicability of these prevention efforts to infections caused by other organisms is not clear. METHODS Multicenter surveillance during 1995 to 1996 for culture-confirmed, early-onset sepsis in an aggregate of 52 406 births; matched case-control study of risk factors for GBS and other sepsis. RESULTS Early-onset disease occurred in 188 infants (3.5 cases per 1000 live births). GBS (1.4 cases per 1000 births) and Escherichia coli (0.6 cases per 1000 births) caused most infections. GBS sepsis less often occurred in preterm deliveries compared with other sepsis. Compared with gestation-matched controls without documented sepsis, GBS disease was associated with intrapartum fever (matched OR, 4.1; CI, 1.2-13.4) and frequent vaginal exams (matched OR, 2.9; CI, 1.1-8. 0). An obstetric risk factor-preterm delivery, intrapartum fever, or membrane rupture >/=18 hours-was found in 49% of GBS cases and 79% of other sepsis. IAP had an adjusted efficacy of 68.2% against any early-onset sepsis. Ampicillin resistance was evident in 69% of E coli infections. No deaths occurred among susceptible E coli infections, whereas 41% of ampicillin-resistant E coli infections were fatal. Ninety-one percent of infants who developed ampicillin-resistant E coli infections were preterm, and 59% of these infants were born to mothers who had received IAP. CONCLUSIONS Either prenatal GBS screening or a risk-based strategy could potentially prevent a substantial portion of GBS cases. Sepsis caused by other organisms is more often a disease of prematurity. IAP seemed efficacious against early-onset sepsis. However, the severity of ampicillin-resistant E coli sepsis and its occurrence after maternal antibiotics suggest caution regarding use of ampicillin instead of penicillin for GBS prophylaxis.

HEPATITIS IN THE OBSTETRIC PATIENT

The six agents identified thus far that cause viral hepatitis are reviewed, and their impact upon pregnancy is described. Although it is the most common cause of jaundice during pregnancy, viral hepatitis does not generally increase the risk of pregnancy complications, nor is it teratogenic. Vertical transmission of some types of viral hepatitis does occur, however.

Use of intrapartum antibiotics and the incidence of postnatal maternal and neonatal yeast infections.

Objectives: To estimate 1) the risk of candidiasis (neonatal thrush or breast infections or both) in nursing mother–infant pairs and 2) whether receipt of intrapartum antibiotics increases this risk. Methods: Demographic and obstetric data were obtained at delivery, and telephone follow-up was obtained at 1 week and 1 and 3 months and recorded in the Lactation Services database, which was reviewed retrospectively. The diagnoses of thrush and breast candidiasis were based on symptoms and patient reports, as per standard clinical practice. For statistical analysis, &khgr;2 analysis and Student t test were used. A value of P < .05 was considered significant. Results: A total of 811 nursing mother–infant pairs were seen between February 1, 2001, and August 31, 2002. Mother–infant pairs with follow-up who nursed for 1 month or longer were included (n = 435). Of these, 173 (39.8%) received intrapartum antibiotics, most (78.6%) for group B streptococci prophylaxis. Overall, 46 mother–infant pairs (10.6%) had either thrush or breast candidiasis (32 with both) within 1 month of delivery. Mothers who were exposed to intrapartum antibiotics were significantly more likely to develop breast candidiasis (odds ratio 2.1, 95% confidence interval 1.08–4.08). Antibiotic-exposed neonates were more likely to develop thrush, although this was not statistically significant. (odds ratio 1.87, 95% confidence interval 0.97–3.63). Antibiotic-exposed infants were younger (mean ± standard deviation, 38.5 ± 1.9 weeks compared with 39.0 ± 1.3 weeks; P = .002), but there were no differences in maternal age, gravity or parity, or route of delivery. Conclusions: Neonatal thrush and maternal breast candidiasis are common early postnatal complications. The higher rates of thrush and breast candidiasis in antibiotic-exposed mother–infant pairs merits further study. Level of Evidence: II-2

Lack of an effect of protease inhibitor use on glucose tolerance during pregnancy

OBJECTIVE: We hypothesized that HIV-positive women on protease inhibitors (PIs) would be more likely to have an elevated glucola test result than those not on PIs. METHODS: We reviewed our database of all HIV-positive pregnant women seen at our hospital. Serum glucose was measured 1 hour following a 50-g glucola load, at approximately 26-28 weeks of gestation. Statistical analysis was performed using Students t-test, Fishers exact test, and the Mann-Whitney rank sum test. RESULTS: Forty-one HIV-infected pregnant women with glucola testing were seen between January 1, 1997 and March 1, 2000. Fourteen patients were on PIs at the time of glucola. One patient in each group had an abnormal glucola test result (glucose >/= 140 mg/dl); both had normal 3-hour glucose tolerance tests. The glucola test results were similar between the PI-exposed and unexposed, with a mean difference of 5.8 mg/dl (95% confidence interval 9.2-20.8 mg/dl). Two neonates (both exposed to PI) had hypoglycemia (glucose < 40 mg/dl). CONCLUSIONS: The use of PIs does not significantly increase the risk of an elevated glucola result, nor is the mean glucola result increased in the women on PIs. The finding of hypoglycemia in neonates exposed to PIs merits further investigation.