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P Duff

Publications and source records attributed to P Duff.

At least 19 recordsLinked to original sources
PubMed2001

Infection, antibiotics, and preterm delivery.

The relationship between genital tract infection and preterm delivery has been established on the basis of biochemical, microbiological, and clinical evidence. In theory, pathogenic bacteria may ascend from the lower reproductive tract into the uterus, and the resulting inflammation leads to preterm labor, rupture of the membranes, and birth. A growing body of evidence suggests that preterm labor and/rupture of the membranes are triggered by micro-organisms in the genital tract and by the host response to these organisms, ie, elaboration of cytokines and proteolytic enzymes. Epidemiologic and in vitro studies do not prove a cause-and-effect relationship between infection and preterm birth. However, the preponderance of evidence indicates that treatment of asymptomatic bacteriuria and symptomatic lower genital tract infections such as bacterial vaginosis (BV), trichomoniasis, gonorrhea, and chlamydia will lower the risk of preterm delivery. Based on current evidence, pregnant women who note an abnormal vaginal discharge should be tested for BV, trichomonas, gonorrhea, and chlamydia. Those who test positive should be treated appropriately. A 3- to 7-day course of antibiotic treatment for asymptomatic bacteriuria during pregnancy is clinically indicated to reduce the risk of pyelonephritis and preterm delivery. Routine screening for chlamydia and gonorrhea should be performed for women at high risk of acquiring sexually transmitted diseases. The practice of routine screening for BV in asymptomatic women who are at low risk for preterm delivery cannot be supported based on evidence from the literature. Routine screening for asymptomatic bacteriuria during pregnancy is cost-effective, particularly in high-prevalence populations. The results of antibiotic trials for the treatment of preterm labor have been inconsistent. In the absence of reasonable evidence that antimicrobial therapy leads to significant prolongation of pregnancy in the setting of preterm labor, antibiotics should be used only for protecting the neonate from group B streptococci sepsis. They should not be used for the purpose of prolonging pregnancy. Multiple investigations have shown that, in patients with preterm premature rupture of the membranes, prophylactic antibiotics are of value in prolonging the latent period between rupture of the membranes and onset of labor and in reducing the incidence of maternal and neonatal infection. The most extensively tested effective antibiotic regimen for prophylaxis involves erythromycin alone or in combination with ampicilln. Controversy still exists regarding the appropriate length and route of antibiotic prophylaxis.

Anti-Bacterial Agents↗
PubMed2001

Amniotic fluid concentrations of matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 1 during pregnancy and labor.

OBJECTIVE: This study was undertaken to determine whether obstetric factors affect the concentrations of matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 1 in the amniotic fluid. STUDY DESIGN: We prospectively collected amniotic fluid samples from 109 women at various stages of pregnancy and labor and determined matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 1 concentrations by means of enzyme-linked immunosorbent sandwich assay systems. With multiple regression analysis we evaluated relationships between amniotic fluid matrix metalloproteinase 9 concentration and tissue inhibitor of metalloproteinase 1 concentration and the following factors: gestational age, presence of labor, cervical dilatation, membrane status, presence of clinical chorioamnionitis, and microbial colonization of the amniotic fluid. RESULTS: The detectable presence of amniotic fluid matrix metalloproteinase 9 was independently associated with intra-amniotic infection, labor, cervical dilatation, and spontaneous rupture of membranes. Chorioamnionitis and amniotic fluid matrix metalloproteinase 9 concentrations were correlated with tissue inhibitor of metalloproteinase 1 levels. CONCLUSIONS: Intra-amniotic infection, advanced labor, and rupture of membranes before the onset of labor were independently associated with the presence of matrix metalloproteinase 9 in the amniotic fluid. Both pathologic and physiologic processes appear to produce shifts in the balance between degradation and synthesis of the extracellular matrix.

Amniotic Fluid↗
PubMed2001

Performance characteristics of putative tests for subclinical chorioamnionitis.

OBJECTIVE: To evaluate amniotic fluid glucose, matrix metalloproteinase (MMP)-9, interleukin (IL)-6, and IL-12 for diagnosing subclinical chorioamnionitis in women with preterm labor. METHODS: Forty-four women in preterm labor at 22-35 weeks gestation with suspected subclinical chorioamnionitis underwent amniocentesis. Amniotic fluid analysis included Gram stain, culture, and determination of glucose, MMP-9, IL-6, and IL-12 concentrations. Median values of these analytes were compared using the Mann-Whitney U test. Sensitivity, specificity, and positive and negative predictive values were calculated for tests using a positive amniotic fluid culture or delivery within 24 hours as the key outcome variables. RESULTS: Amniotic fluid concentrations of glucose, MMP-9, and IL-6 correlated closely with positive culture or delivery within 24 hours. IL- 12 concentrations did not correlate with either a positive culture or delivery within 24 hours. CONCLUSIONS: Amniotic fluid glucose, MMP-9, and IL-6 reliably predict microbial invasion of the amniotic cavity or imminent delivery. IL- 12 values did not correlate with amniotic fluid culture results or imminent delivery.

Amniocentesis↗
PubMed2001

Fas and Fas ligand expression in maternal blood and in umbilical cord blood in preeclampsia.

The Fas-Fas ligand (FasL) pathway of apoptosis is abnormally activated in diseases associated with impaired immune tolerance or chronic inflammation. Pregnancy-related hypertension is a spectrum of disease that commonly causes significant morbidity in women and in their newborn infants, is associated with generalized inflammation, and may be causally related to impaired maternal-fetal tolerance. Our recent observation of enhanced trophoblast expression of FasL in one form of pregnancy-related hypertension led us to hypothesize that this group of disorders might be associated with abnormal activation of the Fas-FasL pathway. To test this hypothesis, we prospectively quantified soluble and leukocyte-associated Fas receptor and FasL in the maternal and umbilical cord blood (CB) sera of 20 gestations complicated by preeclampsia and of 18 normal control gestations, using ELISA and flow cytometric analyses. We determined higher soluble FasL levels in paired maternal and CB sera of hypertensive gestations compared with control gestations (p < 0.01); in contrast, soluble Fas levels were similar between groups. Surface expression of FasL was lower on maternal (p < 0.01) and CB (p < 0.05) neutrophils from affected gestations, whereas surface Fas expression was lower on maternal (p < 0.02), but not CB, neutrophils and lymphocytes. We conclude that expression of Fas and FasL in sera and on leukocytes is altered in gestations complicated by preeclampsia, and speculate that activation of the Fas-FasL pathway mediates associated pathologic processes in affected women and in their neonates.

Antigens, Surface↗
PubMed2000

Expanded-spectrum antibiotics with preterm premature rupture of membranes.

OBJECTIVE: To compare maternal infection rates, neonatal sepsis rates, and bacterial resistance patterns in cases of neonatal sepsis for three antibiotic protocols for women with preterm premature rupture of membranes (PROM). METHODS: From January 1, 1988 to February 28, 1998, women with preterm PROM not requiring immediate delivery were treated according to one of three antibiotic protocols. During three distinct periods, patients received no antibiotics, intravenous ampicillin for 48 hours followed by oral amoxicillin, or intravenous ticarcillin-clavulanic acid for 48 hours followed by oral amoxicillin-clavulanic acid. Rates of chorioamnionitis, endometritis, and neonatal sepsis were compared, as were antimicrobial resistance patterns. Statistical analysis was done using chi(2) analysis, Fisher exact test, and the log-likelihood ratio test. The Bonferroni correction was used for multiple comparisons. RESULTS: During the three periods, preterm PROM was diagnosed in 1695 women. The incidence of endometritis was lower during the third (5.3%) compared with the first (15.1%, P <.001) and second (11.6%, P <.001) protocols. Chorioamnionitis rates were 13.6%, 12.7%, and 15.6% (P =.34) for the first, second, and third periods, respectively, and neonatal sepsis rates were 2.2%, 0.6%, and 1.1% (P =.08), respectively. Neonatal sepsis with gram-negative (P =.02) and ampicillin-resistant (P =.04) organisms was more likely when mothers received antepartum ampicillin or ticarcillin-clavulanic acid. CONCLUSION: Antibiotic therapy for patients with preterm PROM was associated with a decrease in the rate of endometritis and a trend toward less neonatal sepsis but an increase in the proportion of gram-negative and ampicillin-resistant organisms causing neonatal sepsis.

Adult↗
PubMed2000

Amniotic fluid indices of fetal pulmonary maturity with preterm premature rupture of membranes.

OBJECTIVE: To evaluate the performance of the TDx/TDxFLx fetal lung maturity II assay (Abbott Laboratories; Abbott Park, IL) on amniotic fluid (AF) specimens collected vaginally from women with preterm premature rupture of membranes (PROM). METHODS: We reviewed charts of patients with preterm PROM treated at Shands Hospital at the University of Florida from January 1, 1995, to June 30, 1999. Negative predictive values (prediction of the absence of neonatal respiratory distress) of mature (at or above 55 mg/g) and borderline (40-54 mg/g) test results were calculated for 153 women. RESULTS: Respiratory distress syndrome (RDS) occurred with frequencies of one in 42 and three in 29 cases with mature and borderline test results, respectively. All cases of RDS were mild, defined as sustained tachypnea with or without need for supplemental oxygen. With an immature (less than 40 mg/g) test result, 20 of 82 infants developed RDS, and half of those cases were severe, defined as needing mechanical ventilation. Negative predictive values of mature and borderline tests were 97.6% (95% confidence interval [CI] 92.9, 100) and 89.7% (95% CI, 78.3, 100), respectively. CONCLUSION: Mature results from fetal lung maturity tests of vaginally collected AF predict the absence of RDS with a high degree of accuracy.

Adult↗
PubMed1999

Prophylactic cefazolin in amnioinfusions administered for meconium-stained amniotic fluid.

OBJECTIVE: To determine if amnioinfusion with an antibiotic solution decreased the rate of clinical chorioamnionitis and puerperal endometritis in patients with meconium-stained amniotic fluid. METHODS: Patients in labor at 36 weeks of gestation or greater with singleton pregnancies and meconium-stained amniotic fluid were randomized to receive either cefazolin, 1 g/1,000 mL, of normal saline (n = 90) or normal saline (n = 93) amnioinfusion. Rates of clinically diagnosed chorioamnionitis and endometritis and of suspected and culture-proven neonatal infection were determined. RESULTS: Between the study and control groups, the incidences of clinical chorioamnionitis (7.8% vs. 8.6%), endometritis (2.4% vs. 3.5%), aggregate intrauterine infection (10.0% vs. 11.8%), suspected neonatal infection (17.8% vs. 21.5%), and proven neonatal infection (0.0% vs. 2.2%) were not significantly different. CONCLUSIONS: Prophylactic use of cefazolin in amnioinfusions did not significantly reduce rates of maternal or neonatal infection in patients with meconium-stained amniotic fluid.

Adult↗
PubMed1999

Maternal and neonatal infection rates with three different protocols for prevention of group B streptococcal disease.

OBJECTIVES: We compared maternal and neonatal infection rates under 3 different group B streptococcal prevention strategies and also evaluated reasons for each protocol's failures in preventing neonatal disease. STUDY DESIGN: Women who were delivered at our center from August 1, 1991, through April 30, 1998, were managed by 1 of 3 protocols for prevention of early-onset neonatal group B streptococcal infection: a selective screening protocol, The American College of Obstetricians and Gynecologists protocol, and the Centers for Disease Control and Prevention-recommended universal screening strategy. We compared maternal infection rates and neonatal group B streptococcal infection rates under each protocol. We also compared reasons for each protocol's failures in preventing neonatal infection. RESULTS: Clinical chorioamnionitis rates were 7.4% with selective screening, 7.7% under The American College of Obstetricians and Gynecologists' protocol, and 5.2% with universal screening (relative risk 0.7, 95% confidence interval 0.6-0.8). Endometritis rates were 4.0% with selective screening, 4.6% with The American College of Obstetricians and Gynecologists protocol, and 2. 8% with universal screening (relative risk 0.7, 95% confidence interval 0.6-0.8). Overall neonatal group B streptococcal infection rates were lower under the 2 more recent strategies, but not significantly so. Despite the ability of universal screening to find more women at risk for group B streptococcal transmission, half of the neonatal infections under this protocol occurred when the mothers were not considered candidates for prophylaxis. CONCLUSIONS: The Centers for Disease Control and Prevention-endorsed universal screening strategy for group B streptococcal infection prevention was associated with significantly lower rates of clinical chorioamnionitis and endometritis than were the other strategies. We were unable to document statistically significant improvement in neonatal outcome under the universal screening protocol.

Anti-Bacterial Agents↗
PubMed1999

Amniotic fluid matrix metalloproteinase-9 levels in women with preterm labor and suspected intra-amniotic infection.

OBJECTIVE: To determine the accuracy of amniotic fluid (AF) matrix metalloproteinase-9 measurements for diagnosing intra-amniotic infection in women with preterm labor. METHODS: We performed amniocenteses in 44 women between 22 and 35 weeks' gestation who presented to our center with preterm labor and clinical suspicion of intra-amniotic infection. Each sample was analyzed by glucose measurement, Gram stain, and culture for aerobes, anaerobes, and mycoplasmas. We tested the AF for matrix metalloproteinase-9 using gelatin zymography and a commercial enzyme-linked immunosorbent assay (ELISA) system. We calculated accuracy and confidence intervals (CIs) for AF matrix metalloproteinase-9, glucose, and Gram stain for diagnosing intra-amniotic infection, using culture as the criterion standard. RESULTS: All patients who had matrix metalloproteinase-9 detectable by ELISA also demonstrated matrix metalloproteinase-9 by zymography. Six cases of intra-amniotic infection were confirmed by culture (prevalence 14%). The performance statistics of AF matrix metalloproteinase-9 for diagnosing intra-amniotic infection were: sensitivity 83% (95% CI 53, 99), specificity 95% (95% CI 88, 99), positive predictive value 71% (95% CI 37, 99), and negative predictive value 97% (95% CI 92, 99). Two women had false-positive results; one had gram-negative rods on the AF Gram stain and developed clinical signs and symptoms of chorioamnionitis several hours after amniocentesis and the other had a purulent vaginal discharge and an AF glucose level less than 15 mg/dL. Both delivered within 24 hours of amniocentesis. CONCLUSION: Measuring matrix metalloproteinase-9 in the AF appeared to be reliable for diagnosing intra-amniotic infection. An elevated matrix metalloproteinase-9 concentration in the AF at a preterm gestational age may portend imminent delivery regardless of microbiologic confirmation of intra-amniotic infection.

Adult↗
PubMed1998

The association of asymptomatic bacterial vaginosis with upper genital tract infection.

Objective: To determine whether asymptomatic bacterial vaginosis (BV) is associated with upper genital tract inflammation or bacterial colonization.Methods: Fifty nonpregnant women with intact uteri who planned to undergo gynecologic surgery and had no recent symptoms of vaginal infection were enrolled. We obtained a vaginal swab for Gram stain, endocervical swab for chlamydia and gonorrhea DNA probe testing, and Pipelle endometrial biopsy for aerobic and anaerobic cultures and histology. We correlated surgical findings and histology of available surgical specimens with the microbiologic results. The diagnosis of BV was made according to Speigel's criteria. Bacteria isolated from the uterus were classified as high virulence versus low virulence. Contingency tables were analyzed using the chi-square or Fisher Exact tests.Results: Twenty-one of 50 patients had BV on Gram stain, 3 had intermediate BV, and 3 had unreadable slides. Eleven patients had histologic endometritis, including 7 of the 21 with BV. The association between BV and endometritis was not statistically significant. Thirty-eight patients had a positive endometrial culture; 18 of these also had BV and 3 had intermediate BV. Of patients with a positive endometrial culture, isolates from those who also had BV or intermediate BV were more likely to be highly virulent pathogens compared to those who tested negative for BV (P <.05). No patients had positive gonorrhea or chlamydia tests. Of the 37 patients who underwent abdominal surgery, 20 had visible adhesions. The association between adhesions and endometritis, BV, or positive endometrial cultures was not significant.Conclusion: Patients with asymptomatic BV are more likely than patients without BV to have highly virulent bacteria isolated from the endometrium. BV may predispose to upper genital tract infection.

Journal Article↗
PubMed1998

Hepatitis A vaccine: ready for prime time.

Two new inactivated hepatitis A vaccines are available that confer long-term protection against infection. They are indicated for pre-exposure prophylaxis in persons older than 2 years of age. For one vaccine preparation, Vaqta (Merck and Co., West Point, PA), the recommended schedule for adults is a 1.0-mL (50 U of hepatitis A viral antigen) intramuscular dose initially, followed by a booster dose 6-12 months later. Children 2-17 years of age should receive 0.5 mL (25 U of hepatitis A viral antigen) initially, followed by a booster dose 6-18 months later. The adult dosage schedule for Havrix (SmithKline Beecham, Philadelphia, PA) is a 1.0-mL (1440 enzyme-linked immunosorbent assay [ELISA] units) intramuscular dose initially, followed by a 1.0-mL booster dose 6-12 months later. Patients 2-18 years of age should receive doses of 0.5 mL (720 ELISA units). Primary candidates for vaccination are travelers to regions of endemic disease, children living in high-prevalence areas, homosexual males, users of illicit intravenous drugs, persons working directly with nonhuman primates or hepatitis A virus, patients older than 30 years of age with chronic liver disease, and persons who have received a liver transplant or are awaiting one. Seroconversion rates in healthy children and adults exceed 95%. Both vaccines are safe for use in pregnancy. The cost of the vaccine for adult patients is approximately $50 to $60.

Female↗
PubMed1998

Preventing neural tube defects: the importance of periconceptional folic acid supplements.

OBJECTIVE: To inform the obstetrician-gynecologist of recent scientific evidence regarding the use of supplemental folic acid for prevention of neural tube defects (NTDs). DATA SOURCES: We selected English language articles via MEDLINE published from January 1990 through February 1997, using the search terms "folic acid" and "neural tube defect." Additional sources were identified through cross-referencing and through searching selected journals published from March through October 1997. METHODS OF STUDY SELECTION: Articles were selected on the basis of their relevance to the relationship between folate intake and NTD incidence, mechanisms of folate responsive NTD formation, and folate provision strategy. We referenced 55 papers in total. TABULATION, INTEGRATION, AND RESULTS: The majority of evidence demonstrates a decreased incidence of NTDs with increased folic acid consumption. The most convincing trials were performed in Europe among women who were planning pregnancy by using multivitamin or folic acid supplements. Some studies suggest that the protective effect of folate is explained, in many cases, not through correction of dietary deficiencies, but through correction of metabolic defects. Other evidence implies that it reduces NTDs by causing abortion of affected conceptuses. Supplemental folic acid tablets are the most proven means of improving an individual's folate status, but ensuring compliance with a strategy using vitamin tablets is problematic. CONCLUSION: Women of reproductive age should be advised to take multivitamin supplements containing 0.4 mg folic acid daily. Women with previously affected offspring who intend to become pregnant should take daily supplementation containing 4 mg of folic acid in the periconceptional period to reduce the risk of recurrence.

Female↗
PubMed1998

Hepatitis in pregnancy.

Currently, six distinct types of hepatitis virus have been identified: A, B, C, D, E, and G. Hepatitis A virus infection does not cause a chronic carrier state, and perinatal transmission is extremely uncommon. Hepatitis B can be transmitted perinatally, but immunization of the newborn with hepatitis B immune globulin and hepatitis B vaccine markedly reduces the risk of neonatal infection. Hepatitis D virus is dependent on coinfection with the hepatitis B virus for replication. Immunoprophylaxis against hepatitis B also is effective against hepatitis D. Hepatitis C virus is primarily transmitted by the parenteral route and is particularly likely to cause chronic liver disease. Perinatal transmission of hepatitis C principally occurs in women who have high titers of HCV-RNA or who are coinfected with human immunodeficiency virus. At this time, no immunoprophylaxis for hepatitis C is available. Hepatitis G, a recently described organism, is related to hepatitis C. Its clinical significance remains undetermined. Hepatitis E is transmitted in a manner similar to hepatitis A. Perinatal transmission is unusual, but maternal disease is often severe.

Female↗