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Biomedical subjects

R S Gibbs

Publications and source records attributed to R S Gibbs.

At least 19 recordsLinked to original sources
PubMed1992

Characteristics of three vaginal flora patterns assessed by gram stain among pregnant women. Vaginal Infections and Prematurity Study Group.

This study was undertaken to define the characteristics and persistence of vaginal flora in 7918 pregnant women at 23 to 26 weeks' gestation. Vaginal smears were categorized as normal (predominant lactobacilli), intermediate (reduced lactobacilli), or positive for bacterial vaginosis. The women with normal flora were least likely to have elevated vaginal pH, amine odor, milky discharge, or colonization by Gardnerella, Bacteroides, or genital mycoplasmas. Women with intermediate vaginal flora had intermediate frequencies of these clinical signs and microorganisms. Group B streptococci and yeast were associated with normal or intermediate flora, whereas Neisseria gonorrhoeae and Chlamydia trachomatis were recovered more frequently from women with intermediate flora or bacterial vaginosis. Trichomonas vaginalis was most associated with intermediate flora. At follow-up, 81% of the women with normal flora had remained normal. Of the women with intermediate flora, 32% acquired bacterial vaginosis and 30% shifted to normal flora. Only 12% of the women with bacterial vaginosis had shifted to normal flora. We conclude that there are two primary stable vaginal flora patterns (normal flora or bacterial vaginosis) and a third less distinct transitional flora pattern between these two.

Adolescent↗
PubMed1992

A review of premature birth and subclinical infection.

Premature birth causes high rates of neonatal morbidity and mortality. There are multiple causes of preterm birth. This article reviews the evidence linking subclinical infection and premature birth. Although maternal genital tract colonization with specific organisms has been inconsistently associated with preterm birth and/or premature rupture of membranes, some infections have been consistently associated with preterm delivery. The association of histologic chorioamnionitis with prematurity is a consistent finding, but the mechanisms require further study. The relationship between histologic chorioamnionitis infection and the chorioamnionitis of prematurity requires additional research. A varying number of patients in "idiopathic" preterm labor have positive amniotic fluid cultures (0% to 30%), but it is not clear whether infection preceded labor or occurred as a result of labor. Evidence of subclinical infection as a cause of preterm labor is raised by finding elevated maternal serum C-reactive protein and abnormal amniotic fluid organic acid levels in some patients in preterm labor. Biochemical mechanisms for preterm labor in the setting of infection are suggested by both in vitro and in vivo studies of prostaglandins and their metabolites, endotoxin and cytokines. Some, but by no means all, antibiotic trials conducted to date have reported decreases in prematurity. These results support the hypothesis that premature birth results in part from infection caused by genital tract bacteria. In the next few years, research efforts must be prioritized to determine the role of infection and the appropriate prevention of this cause of prematurity.

Anti-Bacterial Agents↗
PubMed1992

Amniotic fluid tumor necrosis factor-alpha and interleukin-1 in a rabbit model of bacterially induced preterm pregnancy loss.

OBJECTIVE: The objective of this study was to determine whether the cytokines tumor necrosis factor-alpha, interleukin-1 alpha, and interleukin-1 beta were produced in the amniotic fluid of the rabbit after intracervical inoculation with Escherichia coli. STUDY DESIGN: Timed pregnant rabbits on day 21 (70% of gestation) were inoculated with a hysteroscope intracervically with 10(4) to 10(5) colony-forming units Escherichia coli or sterile saline solution. Escherichia coli-inoculated animals (N = 16) were put to death at 4, 8, 12, and 16 hours after inoculation. Control animals (N = 6) were put to death at similar intervals. At death, cultures were taken from endometrium, amniotic fluid, peritoneum, and blood. Amniotic fluid was collected and assayed for tumor necrosis factor bioactivity by a modified fibroblast cytotoxic assay in L929 cells, for interleukin-1 alpha, and interleukin-1 beta with a specific radioimmunoassay, and for prostaglandin E2 and prostaglandin F2 alpha by radioimmunoassay. RESULTS: Levels of amniotic fluid tumor necrosis factor-alpha, interleukin-1 alpha, and interleukin-1 beta were elevated as early as 4 hours after inoculation in some animals and by 12 to 16 hours after inoculation in all. Levels of all three cytokines correlated significantly with time from intracervical inoculation with Escherichia coli (p < 0.05). Levels of amniotic fluid prostaglandin E2 and prostaglandin F2 alpha correlated significantly with time from intracervical inoculation with Escherichia coli (p < 0.05). CONCLUSIONS: Levels of tumor necrosis factor-alpha, interleukin-1 alpha, interleukin-1 beta, prostaglandin E2 and prostaglandin F2 alpha are elevated in the amniotic fluid of rabbits after intracervical inoculation with Escherichia coli. Similarity exists between elevations of amniotic fluid cytokines in this model and in cases of intraamniotic infection and preterm labor unresponsive to tocolytics in humans. Modulation of cytokines may offer a strategy for improvement of outcome in this experimental model of infection-induced pregnancy loss.

Abortion, Veterinary↗
PubMed1992

Polymerase chain reaction-based genotyping for allotypic markers of immunoglobulin kappa shows allelic association of Km with kappa variable segment.

Allotypic markers of immunoglobulin kappa (Km) may be determined using a novel method of amplification of the constant segment (C kappa) (IGKC) by polymerase chain reaction (PCR) followed by restriction enzyme digestion. Restriction sites in the C kappa PCR product correlate with allotypic differences among Km(1), Km(1,2), and Km(3) alleles. An AccI site in the PCR product correlates with Km(3); and presence or absence of a MaeII site correlates with the Km(1) or Km(1,2) allele, respectively. Km allelic frequencies were determined in a Caucasian population and compared to genotypic frequencies of nearby polymorphic markers. Among unrelated individuals with rheumatoid arthritis (RA) and controls, there is no evidence of allelic association between CD8A and polymorphic markers of the immunoglobulin kappa region [a V kappa (IGKV) BglII polymorphism about 24 kb centromeric to C kappa, Km allotype, and a SacI polymorphism 3.5 kb telomeric to the C kappa segment]. Similarly, there is no allelic association of the SacI C kappa polymorphism with Km or with the BglII V kappa polymorphism. However, there is evidence of allelic association of V kappa B3 and Km, specifically between the V kappa BglII 2.2-kb allele and Km(3) and also between the V kappa 3.5-kb allele and Km(1,2). Therefore, Km typing by PCR-based methods suggests the presence of allelic association between polymorphisms within the coding region of the C kappa segment and the nearest V kappa segment.

Alleles↗
PubMed1992

The effects of pH and osmolality on bacterial growth in amniotic fluid in a laboratory model.

In studying the effects of amniotic fluid on bacterial growth in a laboratory model, we noted that the pH of the fluid appeared to exert an independent effect. This study was designed to test the ability to control the growth of Escherichia coli in amniotic fluid simply by controlling two important growth conditions, pH and osmolality. The effects of pH and osmolality on growth of E. coli were systematically studied in a standard media and in amniotic fluid. Optimal ranges in standard media were pH of 5.6 to 6.6 and osmolality of 150 to 215 mOsm. When the results of growth at 24 hours were corrected for pH by analysis of covariance, the presence of amniotic fluid or phosphate had no effect. We found pH to be the only variable predictive of bacterial growth in amniotic fluid in this laboratory model.

Amniotic Fluid↗
PubMed1992

Life-threatening puerperal infection due to group A streptococci.

We describe two patients with life-threatening puerperal infection due to group A beta-hemolytic streptococcus. Each patient had bacteremia, shock, and multi-organ involvement. Both cases were compatible with a recently described streptococcal toxic shock-like illness. Both women failed to improve despite vigorous medical and antibiotic therapies, and each required hysterectomy. Obstetricians should be alert to the importance of early diagnosis and treatment of this potentially lethal infection.

Adult↗
PubMed1992

A retrospective review of the efficacy and safety of prostaglandin E2 with premature rupture of the membranes at term.

OBJECTIVE: The purpose of this study was to assess rates of endometritis, clinical chorioamnionitis, cesarean delivery, and neonatal sepsis from the records of patients with premature rupture of the membranes (PROM) and an unfavorable cervix treated with vaginal prostaglandin (PG) E2 in comparison with those in the literature. METHODS: Using a computer data base at Denver General Hospital, we identified 146 women with PROM and cervical dilatation of 2 cm or less at term who were treated with PGE2 gel or suppositories. The records were reviewed to identify rates of maternal and neonatal infection and complications, as well as cesarean delivery. RESULTS: The cesarean rate was 12%. Chorioamnionitis developed in 6.8% of the study group and endometritis in 2%. Neonatal complications were limited to two with low Apgar scores (less than 7 at 5 minutes), one with microbiologically confirmed sepsis, and two with positive urine counterimmunoelectrophoresis for group B streptococcus. The only instance of neonatal sepsis occurred in a patient with rupture of membranes longer than 24 hours. CONCLUSIONS: The use of vaginal PGE2 suppositories for induction of labor and cervical ripening in term patients with PROM was accompanied by a high rate of vaginal delivery and a low rate of maternal and neonatal complications in a city hospital setting.

Administration, Intravaginal↗
PubMed1979

Immunization of pregnant women with influenza A/New Jersey/76 virus vaccine: reactogenicity and immunogenicity in mother and infant.

The safety and immunogenicity of inactivated influenza virus vaccines in pregnant women have not been adequately investigated. In this study, 56 women received inactivated influenza A/New Jersey/76 virus vaccine during the second and third trimesters of pregnancy. No significant immediate reactions or increased fetal complications were associated with administration of the vaccine. The antibody response of the pregnant women to the vaccine was similar to that of nonpregnant adults. Forty mother-infant pairs were available for antibody surveillance. At delivery, reciprocal antibody titers of greater than or equal to 20 were present in 11 (42%) newborn (cord) sera and 15 (58%) maternal sera. Three months later, sera from only three infants (12%) contained this level of antibody. At six months, the serum of only one infant contained this level of antibody. At six months, the serum of only one infant contained detectable antibodies. Levels of passively transferred antibodies from prior maternal infection with influenza A/Victoria/75 virus also declined rapidly following birth. It is possible that immunization of pregnant women can provide sufficient protection of the newborn infants by transfer of antibodies through the placenta if (1) a more potent influenza vaccine, possibly used with booster dosing, is administered, and (2) the women deliver just prior to or during the influenza season.

Antibodies, Viral↗
PubMed1978

Antibiotic therapy of endometritis following cesarean section. Treatment successes and failures.

A prospective clinical and microbiologic study was carried out on 413 indigent patients undergoing cesarean section. Operative site infection developed in 160 (38.5%). Initial treatment with penicillin and kanamycin was successful in 125 of these 160 infections (78%). Thirty-five patients (22%) failed to respond to penicillin and kanamycin and were treated with clindamycin or chloramphenicol. Twenty-eight of the 35 responded promptly to the additional antibiotic therapy. The remaining 7 patients (4%) had either abscesses, hematomas, or presumed septic pelvic thrombophlebitis. Among patients with anaerobic cultures, B fragilis was isolated with 12% with a good response to penicillin-kanamycin, but from 53% with a poor response to penicillin-kanamycin and with a good response to clindamycin or chloramphenicol. Similar critical evaluations of other antibiotic regimens are needed.

Anti-Bacterial Agents↗
PubMed1978

Internal fetal monitoring and maternal infection following cesarean section. A prospective study.

A prospective clinical and microbiologic study was performed on 419 patients undergoing cesarean section. A multivariant analysis revealed that labor, rupture of the membranes, and vaginal examinations each had a much greater relative importance than did internal monitoring in determining infection. In an alternative analysis, patients with internal monitoring had no increase in frequency or severity of infection, beyond that imposed by labor and rupture of membranes. Further, endometrial cultures from patients developing infection after internal monitoring were found to have the same bacteria as the cultures of patients developing infection without monitoring.

Adult↗
PubMed1977

A pure enterococcal abscess after cesarean section.

The pathogenic role of the enterococcus in pelvic infections is controversial. This case report of a pure enterococcal abscess developing after cesarean section supports the view that this organism can be a primary pathogen in obstetric and gynecologic infections. Because of its unusual sensitivity pattern, the enterococcus requires specific antibiotic therapy.

Abscess↗
PubMed1977

Acute pancreatitis in pregnancy with Ascaris infestation.

Two cases of acute pancreatitis in pregnancy occurred among Vietnamese evacuees in Arkansas. In both cases, Ascaris lumbricoides seemed the likely cause. In endemic areas including the rural southeastern United States, a high index of suspicion for ascariasis is needed because these worms may cause a variety of abdominal disorders including pancreatitis, cholecystitis, and bowel obstruction. In appropriate settings, a therapeutic trial with antihelminthics is indicated.

Acute Disease↗
PubMed1977

Amniotic fluid neutrophils prior to Cesarean section and intrauterine infection.

Amniotic fluid from 35 patients delivered by cesarean section was examined by Wright's stain. Of the patients in labor and with rupture of the membranes, 32% had more than 1 polymorphonuclear neutrophil per oil field (PMN/OF) while 68% had less than 1 PMN/OF. In both groups, endometritis occurred frequently, and fever indexes were similar. With ruptured membranes prior to cesarean section, observing greater than 1 PMN/OF of amniotic fluid did not discriminate groups at high and low risk for intrauterine infection.

Amniotic Fluid↗
PubMed1976

Bacteriologic effects of prophylactic antibiotics in cesarean section.

An eight-hour course of prophylactic clindamycin and gentamicin was given to 54 service patients undergoing cesarean section. Aerobic and anaerobic endometrial cultures obtained from eight patients who developed endometritis after prophylaxis revealed major changes in flora. Compared to infected patients who had received no prophylaxis, the clindamycin-gentamicin group had marked decreases in aerobic and anaerobic cocci and Bacteroides but increases in E. coli and enterococci. However, this regimen was found to be no more effective than the previously reported regimen of ampicillin and kanamycin.

Ampicillin↗