Increasing evidence links altered intestinal flora in infancy to eczema and asthma. No studies have investigated the influence of maternal intestinal flora on wheezing and eczema in early childhood.

Preterm labour, premature prelabour rupture of membranes and low birth weight have all been associated with either specific maternal genital tract infections or an altered vaginal microflora during pregnancy. Factors that influence the variation in microbial-host interaction play an important role in individual susceptibility to adverse pregnancy outcomes. The innate immune responses at mucosal surfaces play a crucial role against microbial invasion. Multiple genes are responsible for the regulation of the innate immune system. Genetic polymorphisms that disrupt innate immune recognition or the responses to infectious microorganisms could explain the alterations in microflora and individual susceptibility to pregnancy complications.

Epidemiologists have grouped the multiple disorders that lead to preterm delivery before the 28th week of gestation in a variety of ways. The authors sought to identify characteristics that would help guide how to classify disorders that lead to such preterm delivery. They enrolled 1,006 women who delivered a liveborn singleton infant of less than 28 weeks' gestation at 14 centers in the United States between 2002 and 2004. Each delivery was classified by presentation: preterm labor (40%), prelabor premature rupture of membranes (23%), preeclampsia (18%), placental abruption (11%), cervical incompetence (5%), and fetal indication/intrauterine growth restriction (3%). Using factor analysis (eigenvalue = 1.73) to compare characteristics identified by standardized interview, chart review, placental histology, and placental microbiology among the presentation groups, the authors found 2 broad patterns. One pattern, characterized by histologic chorioamnionitis and placental microbe recovery, was associated with preterm labor, prelabor premature rupture of membranes, placental abruption, and cervical insufficiency. The other, characterized by a paucity of organisms and inflammation but the presence of histologic features of dysfunctional placentation, was associated with preeclampsia and fetal indication/intrauterine growth restriction. Disorders leading to preterm delivery may be separated into two groups: those associated with intrauterine inflammation and those associated with aberrations of placentation.

OBJECTIVE: Investigations of the possible role of polymorphic genes in pregnancy outcome may be influenced by ethnic variations in genotype or allele frequencies. Differences in allelic carriage of immune system-related genes among white, black, and Hispanic pregnant women living in New York City and Boston were evaluated.METHODS: DNA was extracted from buccal or vaginal epithelial cells collected from 198 white, 75 black, and 114 Hispanic pregnant women who delivered at term and who had no history of a preterm birth. Genetic polymorphisms in the immunoregulatory genes encoding interleukin (IL)-1beta, tumor necrosis factor-alpha, IL-4, IL-10, IL-1 receptor antagonist (IL-1ra), mannose-binding lectin, toll-like receptor-4, and the 70-kDa heat shock protein were determined.RESULTS: Allele 2 of the IL-1ra gene (IL1RN*2) and IL-4 -590C homozygosity were 4-fold less common in blacks than in whites or Hispanics (P <.001). The IL-4 -590T allele was almost 2-fold more common in Hispanics than in whites (P <.001). The frequency of the 70-kDa heat shock protein 1267G allele was at least 1.4 times greater in blacks compared with whites (P <.001) or Hispanics (P = .002), whereas the homozygous mannose-binding lectin codon 54G allele was observed at least 4.5 times more often in Hispanics compared with whites (P = .007) or blacks (P = .02).CONCLUSION: Investigations of the role of genetic factors affecting pregnancy outcome must be cognizant of ethnic variations when enrolling case and control subjects for studies on allele and genotype frequencies. (C) 2004 by The American College of Obstetricians and Gynecologists.

Objective: This study investigated the association among the inducible 70-kd heat shock protein, cytokines, and microbial flora in the vagina in mid trimester pregnant women and subsequent preterm delivery.Study design: Vaginal samples from 205 pregnant women, which were collected at 18 to 22 weeks of gestation, were analyzed for qualitative and quantitative vaginal microflora and for 70-kd heat shock protein, interleukin-1beta, interleukin-1 receptor antagonist, and tumor necrosis factor-a by enzyme-linked immunosorbent assay. Pregnancy outcome data were obtained subsequently.Results: The 70-kd heat shock protein was detected in 38 vaginal samples (18.5%). Its presence was associated with elevated vaginal pH, a diagnosis of bacterial vaginosis, and elevated interleukin-1beta receptor antagonist levels (P < .001). Among women with bacterial vaginosis, 70-kd heat shock protein-positive Subjects had a > 80% increase in median vaginal concentration of interleukin-1beta receptor antagonist (P < .05).Conclusion: Vaginal 70-kd heat shock protein expression is associated with the down-regulation of the proinflammatory Immune response to abnormal vaginal flora in mid trimester pregnant women. (C) 2005 Elsevier Inc. All rights reserved.

Objective: The relationship between a single nucleotide polymorphism (TLR4 896 A>G) in the toll-like receptor-4 (TLR4) gene, qualitative and quantitative changes in vaginal micro-flora and vaginal interleukin (IL)-1β and IL-1 receptor antagonist (IL-1ra) concentrations in pregnant women were evaluated. Study design: Qualitative and quantitative microbial methods were used to characterize vaginal micro-flora of 238 women at 18–22 weeks gestation. Polymerase chain reaction was used to determine TLR4 genotype. IL-1β and IL-1ra concentrations in vaginal lavage samples were measured by ELISA. Results: The TLR4 variant was identified in 10.3% of women. Carriage of this variant was associated with a median increase in vaginal pH (P=0.05), a greater than 10-fold increase in vaginal Gardnerella vaginalis levels (P<0.0001) and a 10-fold increase in the vaginal concentration of three species of anaerobic Gram-negative rods, Prevotella, Bacteroides, and Porphyromonas (P=0.08). Colonization with G. vaginalis and/or the anaerobic Gram-negative rods resulted in elevated vaginal IL-1 (P=0.01) and IL-1ra (P<0.0002) concentrations in women who were TLR4 896A homozygotes, but not in TLR4 896G carriers. Conclusion: The TLR4 896 A>G polymorphism contributes to inter-individual differences in the vaginal immune defense against G. vaginalis and anaerobic Gram-negative rods.

The epidemiology of clinically recognized community-acquired Clostridium difficile-associated diarrhea was assessed in a retrospective cohort study of members of a health maintenance organization (HMO). Potential cases were identified through positive toxin assay results and confirmed by review of automated full-text medical records. Of 51 cases identified (7.7 per 100,000 person-years), 42 (82%) were diagnosed and treated exclusively in the ambulatory care setting; 33 cases occurred within 42 days after 494,491 exposures to antibiotics dispensed by an HMO pharmacy. Antibiotic-specific attack rates varied from 0 to 2040 cases per 100,000 exposures. Increased age was associated with C. difficile-associated diarrhea (P < .001). Age-adjusted antibiotic-specific attack rates were at least 10-fold higher (P < .05) for nitrofurantoin, cefuroxime, cephalexin plus dicloxacillin, ampicillin/clavulanate plus cefaclor, and ampicillin/clavulanate plus cefuroxime than for ampicillin or amoxicillin; several other antibiotics were associated with similar but not significantly increased risks.

PURPOSE:This study was undertaken to assess the electron microscopic and microbiologic findings in tissue biopsy samples from patients with pouchitis and to compare them with findings in patients with normal pouches, conventional ileostomies, and normal ileum.METHODS:Tissue samples were obtained from 78 patients: 23 patients with normal pouches endoscopically and histologically (Group 1), 12 patients with endoscopic and histologic evidence of inflammation (pouchitis) (Group 2), 14 patients who had either endoscopic or histologic evidence of inflammation but not both (Group 3), 20 patients with conventional ileostomies (Group 4), and 9 patients without ileostomies from whom biopsy samples of normal ileum were obtained (Group 5).RESULTS:The mean total aerobic facultative counts in the biopsy samples from the pouchitis patients were significantly higher when compared with biopsy samples from Groups 4 and 5 (P < 0.05). There were no significant differences in the mean anaerobic counts among the five groups. Positive cultures were obtained in 90 percent of patients with pouches compared with 69 percent of patients with conventional ileostomies or normal ileum (P < 0.05). Intramural bacteria were observed on electron microscopy in biopsy specimens of 47 percent patients with pouches compared with 14 percent of patients with conventional ileostomies or normal ileum (P < 0.05). However, the proportion of patients with positive cultures or intramural bacteria was not increased in the pouchitis group compared with the normal pouch group.CONCLUSION:These data suggest that intramural aerobic facultative bacterial counts are elevated in patients with pouchitis and may play a role in the pathogenesis of pouchitis.

Saladino, R; Garcia, C T; Thompson, C; Hammer, B; Parsonnet, J; Novitsky, T; Onderdonk, A; Siber, G; Fleisher, GAuthor Information

One hundred and seventeen coded intestinal biopsies were examined by electron microscopy and evaluated for morphological evidence of mast cell and basophil secretion in situ. Sixty percent of the biopsies had evidence of secretion. Mast cell secretion was evident in control biopsies, many of which were obtained from uninvolved tissues of patients with inflammatory bowel disease. Biopsies of inflamed continent pouches from ulcerative colitis (UC) patients showed more mast cell secretion than noninflamed UC pouch biopsies. This evidence of mast cell secretion supports recent work that documents high constitutive levels of histamine in jejunal fluids of Crohn's disease patients and suggests a proinflammatory role for mast cells in inflammation associated with pouchitis.

The ability of Escherichia coli to colonize the large bowels of animals is related to many factors inherent to the intestinal environment and the bacterium. The use of germfree mice eliminates the competition between E. coli and the other microflora and allows most E. coli strains to colonize. We found that E. coli K-12 strains differing in chromosomal antibiotic resistance could monoassociate in germfree mice in large numbers. However, when two or more strains were in competition with each other, we detected quantitative differences in the abilities of the strains to colonize. The order of colonizing ability was as follows: nalidixic acid resistance greater than streptomycin resistance greater than rifampin resistance. We also found that a nalidixic acid-resistant strain bearing plasmid pBR322 colonized less efficiently and at lower levels when in competition with the nalidixic acid-resistant strain. Studies of the membrane proteins of the various strains indicated that changes in membrane proteins occurred concomitantly with altered resistance to antimicrobial agents. These results suggest that chromosomally linked alterations in antimicrobial sensitivity may also reflect changes in membrane proteins and a decreased ability to colonize mammalian intestines in otherwise isogenic bacterial strains.

Survival in the mouse and human intestine of Escherichia coli host-vector systems used and proposed for recombinant DNA technology was assessed. There was no detectable survival of severely disabled E. coli K12 strain χ1776 in mice or in human subjects 24 hours after ingestion. The same strain bearing the plasmid pBR322, however, was recovered from human subjects for 4 days in amounts of six organisms for every million ingested. Nondisabled E. coli K12 strain χ1666, with or without pBR322, survived in 10 4 -fold greater numbers and for 2 days longer, with better recovery of the plasmid-containing derivative. Although the plasmid-bearing strains were recovered for longer periods, no intestinal colonization was noted. Despite the presence of pBR322 for a maximum of 6 days in the human intestine, there was no evidence that it was transferred from either bacterial host to endogenous aerobic fecal bacteria.

A technique is described for obtaining quantitative cultures of endodontic specimens. Paper point samplings were placed in a diluted salt solution, vortexed, and then cultured quantitatively using serial dilutions plated onto multiple media. Specimen weight was determined by weighing the point before and after specimen collection. This method was used in 10 nonvital teeth and showed a mean concentration of 107.7 bacteria per gram of sample. Nine specimens yielded a mixed aerobic-anaerobic flora, and there was an average of five different bacterial species per specimen in concentrations exceeding 105/gm.