Biomedical subjects

B Foxman

Publications and source records attributed to B Foxman.

At least 37 records · Page 2Linked to original sources

PubMed2000

Pathogenesis of Urinary Tract Infection: the Role of Sexual Behavior and Sexual Transmission.

Acute urinary tract infection (UTI) is an extremely common clinical entity that affects almost half of all women in the United States, and accounts for more than 7 million physician visits, annually, in this country. Sexual behavior and UTI history are the most important predictors of UTI risk among sexually active young women. Whether sexual behavior has similar impact on UTI risk in older women is unknown. Postcoital prophylaxis has been investigated as a strategy for the prevention of recurrent UTI in sexually active women. There are conflicting data regarding the role of voiding habits in relation to sexual intercourse and the risk of UTI. Finally, there are interesting epidemiologic studies suggesting that uropathogenic Escherichia coli may be transmitted between sex partners. We review the recent literature regarding these different areas, and comment on the potential role of sexual transmission in UTI.

Journal Article↗

PubMed2000

Urinary tract infection: self-reported incidence and associated costs.

PURPOSE: To estimate the annual incidence, cumulative probability of presumed urinary tract infection (UTI) by age, and the social costs. METHODS: Analysis of a random digit dialing survey of 2000 women in the United States. RESULTS: 10.8 percent (95% CI: 9.4, 12.1%) of women aged 18 and older reported at least one presumed UTI during the past 12 months, with the majority of the cases occurring among women with a history of two or more UTI episodes in their life. We estimate that by age 24, one-third of women will have at least one physician-diagnosed UTI that was treated with prescription medication. Overall, an estimated 11.3 million women in the United States had at least one presumed UTI treated with antibiotics in 1995. We estimate the annual cost of UTI cases with prescriptions to be $1.6 billion in 1995. If the costs occurring after 1995 are discounted at 5% annually, the total cost over 20 years has a present value of $25.5 billion. CONCLUSION: If a vaccine were developed that would prevent either initial or recurrent UTI the net benefits to society would be substantial, even at a developmental cost of one billion dollars.

Adolescent↗

PubMed2000

Candida vaginitis: self-reported incidence and associated costs.

BACKGROUND AND OBJECTIVES: Incidence of Candida vaginitis by age and racial or ethnic group is poorly described. GOAL: Estimate incidence, cumulative probability of presumed C vaginitis by age, racial or ethnic group, and associated costs. STUDY DESIGN: Random digit-dialing survey of 2000 US women. RESULTS: A total of 6.5 percent (95% CI, 5.4-7.5%) of women older than 18 years reported a least one episode of presumed C vaginitis during the previous 2 months. Women reporting a 1-year period with four or more episodes comprised 8.0% of the sample but accounted for 37.2% of women reporting episodes. Black women reported approximately three times more yeast infections in the previous 2 months (17.4%; 95% CI, 11.2-23.5%) than white women (5.8%; 95% CI, 4.7-6.9%). CONCLUSION: The high incidence and the propensity for recurrence underscore the need for a better understanding of the epidemiology and pathogenesis, and stress the need for the development of more accurate, rapid diagnostics and effective treatments.

Adolescent↗

PubMed2000

Integrated genomic map from uropathogenic Escherichia coli J96.

Escherichia coli J96 is a uropathogen having both broad similarities to and striking differences from nonpathogenic, laboratory E. coli K-12. Strain J96 contains three large (>100-kb) unique genomic segments integrated on the chromosome; two are recognized as pathogenicity islands containing urovirulence genes. Additionally, the strain possesses a fourth smaller accessory segment of 28 kb and two deletions relative to strain K-12. We report an integrated physical and genetic map of the 5,120-kb J96 genome. The chromosome contains 26 NotI, 13 BlnI, and 7 I-CeuI macrorestriction sites. Macrorestriction mapping was rapidly accomplished by a novel transposon-based procedure: analysis of modified minitransposon insertions served to align the overlapping macrorestriction fragments generated by three different enzymes (each sharing a common cleavage site within the insert), thus integrating the three different digestion patterns and ordering the fragments. The resulting map, generated from a total of 54 mini-Tn10 insertions, was supplemented with auxanography and Southern analysis to indicate the positions of insertionally disrupted aminosynthetic genes and cloned virulence genes, respectively. Thus, it contains not only physical, macrorestriction landmarks but also the loci for eight housekeeping genes shared with strain K-12 and eight acknowledged urovirulence genes; the latter confirmed clustering of virulence genes at the large unique accessory chromosomal segments. The 115-kb J96 plasmid was resolved by pulsed-field gel electrophoresis in NotI digests. However, because the plasmid lacks restriction sites for the enzymes BlnI and I-CeuI, it was visualized in BlnI and I-CeuI digests only of derivatives carrying plasmid inserts artificially introducing these sites. Owing to an I-SceI site on the transposon, the plasmid could also be visualized and sized from plasmid insertion mutants after digestion with this enzyme. The insertional strains generated in construction of the integrated genomic map provide useful physical and genetic markers for further characterization of the J96 genome.

Blotting, Southern↗

PubMed2000

Molecular epidemiologic approaches to urinary tract infection gene discovery in uropathogenic Escherichia coli.

Urinary tract infection (UTI) is one of the most frequently acquired bacterial infections. The vast majority of UTIs are caused by a large, genetically heterogeneous group of Escherichia coli. This genetic diversity has hampered identification of UTI-related genes. A three-step experimental strategy was used to identify genes potentially involved in E. coli UTI transmission or virulence: epidemiologic pairing of a UTI-specific strain with a fecal control, differential cloning to isolated UTI strain-specific DNA, and epidemiologic screening to identify sequences among isolated DNAs that are associated with UTI. The 37 DNA sequences initially isolated were physically located all over the tester strain genome. Only two hybridized to the total DNA of the sequenced E. coli K-12 strain; eight sequences were present significantly more frequently in UTI isolates than in fecal isolates. Three of the eight sequences matched to genes for multidrug efflux proteins, usher proteins, and pathogenicity island insertion sites, respectively. Using population characteristics to direct gene discovery and evaluation is a productive strategy applicable to any system.

Adolescent↗

PubMed2000

Respiratory symptoms in mothers of young children.

OBJECTIVES: Children receiving child care outside the home are at greater risk of upper respiratory infection, but whether parents of those children are also at increased risk is undocumented. We describe the incidence of 2 or more respiratory symptoms in the previous 2 weeks among 185 mothers of children 3 years of age or younger by child care use. METHODS: Mothers in Michigan and Nebraska were interviewed by phone regarding respiratory symptoms, use of outside child care (for an index child), sleeping habits, and demographic information. RESULTS: Nearly one half (46.5%) reported 2 or more symptoms during the past 2 weeks; 15.1% had contacted a health care provider and 13.0% spent 1 or more days in bed because of their symptoms, which lasted an average of 5.5 days. Prevalence of symptoms was invariant to sociodemographic characteristics. Mothers using outside child care (74.6%) were twice as likely as those without outside care to have been ill in the past 2 weeks (odds ratio: 2.26; 95% confidence interval [CI]: 1.12,4.54). Most mothers (69.2%) reported having their sleep interrupted by their children at least once in the last 2 weeks or sharing a bed with a child part or all of the night (61.1%); 25.4% slept 6 hours or less nightly. Women reporting that they rarely or never felt rested (26. 5%) were 2.65 times more likely to be ill (95% CI: 1.26,5.55), compared with those reporting that they frequently or always felt rested (46.5%), after adjusting for any outside child care. CONCLUSIONS: Future studies should focus on risk factors that can be modified to reduce illness among both children and their parents.

Adult↗

PubMed1999

Urinary Tract Infection in Postmenopausal Women.

Urinary tract infection (UTI) is common in postmenopausal women; the estimated incidence ranges from 4% to 15%. The clinical presentation of UTI is somewhat different in postmenopausal older women than it is in younger women: postmenopausal women are less likely to report frequency, dysuria, hematuria, and fever, but are more likely to report flank pain. Other than UTI history, risk factors for symptomatic UTI among postmenopausal women are poorly described. Hormonal replacement therapy minimizes physiologic changes associated with menopause that lead to genitourinary symptoms and, potentially, to UTI, but whether this therapy is appropriate for the prevention of recurrent UTI in postmenopausal women is uncertain.

Journal Article↗

PubMed1999

Epidemiology of vulvar vestibulitis syndrome: an exploratory case-control study.

BACKGROUND: Vulvar vestibulitis syndrome (VVS) is a chronic, persistent syndrome characterised by vestibular pain, tenderness, and erythema. The aetiology of VVS is unknown and few of the hypothesised risk factors have been tested in controlled studies. METHODS: Using a matched case-control study design, medical, sexual, health behaviour, and diet history of 28 women with VVS were compared with 50 friend controls without VVS to identify possible causal factors. RESULTS: Cases were more likely than controls to report every vaginal and urinary symptom at the time of interview measured, particularly vaginal soreness or pain (60.7%) and pain during intercourse (64.3%). There were no significant differences between cases and controls with respect to sexual behaviour. Cases were more likely than controls to report self reported history of physician diagnosed bacterial vaginosis (OR = 22.2, 95% CI = 2.8, 177.2, p value = 0.0001), vaginal yeast infections (OR = 4.9, 95% CI = 1.4, 18.0, p value = 0.01), and human papillomavirus (OR = 7.1, 95% CI = 0.6, 81.2, p value = 0.08). There were no differences between cases and controls with respect to dietary intake of oxalate. Cases were more likely than controls to report poor health status (OR = 5.7, 95% CI = 1.1, 28.7, p value = 0.02) and history of depression for 2 weeks or more during the past year (OR = 4.4, 95% CI = 1.6, 12.3, p value = 0.002). CONCLUSION: Self reported history of bacterial vaginosis, yeast infections, and human papillomavirus were strongly associated with VVS. An infectious origin for VVS should be pursued in larger controlled studies, using questionnaire and laboratory measures.

Adolescent↗

PubMed1999

Sensitivity and specificity of asthma definitions and symptoms used in a survey of childhood asthma.

We compared the ability of definitions/symptoms of asthma to identify urban, elementary schoolchildren with physician-diagnosed asthma and bronchial hyperresponsiveness (BHR) post-exercise challenge. Definitions of asthma from the literature were compared, including American Thoracic Society (ATS) and British Medical Research Council (BMRC) definitions. Modified ATS had the highest sensitivity (77%), whereas BMRC had the highest specificity (99%). The most sensitive symptom was "wheeze with cold" (89%). The most specific symptoms were "medication required," and "breathing normal between attacks" (95%). Definitions and symptoms were poor predictors of BHR. Researchers can use these estimates in selecting and defining specific populations of children with asthma.

Asthma↗

PubMed1998

Vulvovaginal candidiasis: epidemiologic, diagnostic, and therapeutic considerations.

Although it is the second most common vaginal infection in North America, vulvovaginal candidiasis is a non-notifiable disease and has been excluded from the ranks of sexually transmitted diseases. Not surprisingly, vulvovaginal candidiasis has received scant attention by public health authorities, funding agencies, and researchers. Epidemiologic data on risk factors and pathogenic mechanisms remain inadequately studied. Most important, standards of care, including diagnosis and therapy, remain undefined. A conference was held in April 1996 to define and summarize what is known and supported by scientific data in the areas of epidemiology, diagnosis, and treatment of vulvovaginal candidiasis; but, more important, the conference aimed at defining what is not known, poorly studied, and controversial. Guidelines for the treatment and diagnosis of the different forms of vulvovaginal candidiasis are suggested.

Antifungal Agents↗

PubMed1998

Frequency and response to vaginal symptoms among white and African American women: results of a random digit dialing survey.

The prevalence of vaginal symptoms and response to those symptoms in a nonclinic setting has not been previously described. Two thousand women living throughout the United States identified by random digit dialing completed a computer-assisted telephone interview about history of vaginal symptoms and use of healthcare services in response to these symptoms. The analysis was limited to 1698 white (WA) and 144 African American (AA) women (n = 1842). An episode of vaginal symptoms of any severity during 1995 was reported by 7.5% of WA women and 18.1% of AA women. Fifty-five percent of WA women and 83% of AA women with symptoms consulted a healthcare professional about their most recent episode. The racial difference in prevalence and consultation was not explained by marital status, education, employment, or lifetime number of sex partners. Most women purchased an over-the-counter antifungal preparation to treat their symptoms, whether or not a physician was consulted. The racial differences in prevalence and use of health services in response to vaginal symptoms observed here should be confirmed, and the potential causes should be explored.

Black or African American↗

PubMed1998

Interrelationships among douching practices, risky sexual practices, and history of self-reported sexually transmitted diseases in an urban population.

GOALS: To describe the interrelationships of douching, sex during menses, dry sex, and anal intercourse and their associations with self-reported history of sexually transmitted diseases (STD). STUDY DESIGN: The authors interviewed by telephone 422 white Americans (WA) and 44 African Americans (AA) selected using random-digit dialing, and 135 AA selected from a listed sample of census tracks having a population of at least 40% AA. RESULTS: After adjusting for lifetime numbers of vaginal sex partners, sex during menses was associated with self-reported history of chlamydial infection among women (WA: odds ratio [OR] = 3.9; confidence interval [CI]: 1.1, 14.0; AA: OR = 1.6; CI: 0.6, 4.2). Anal sex was associated with self-reported history of genital warts, genital herpes, hepatitis, and gonorrhea; douching with a twofold increase in self-reported pelvic inflammatory disease. Anal sex was most common in women with a history of same- and opposite-sex partners. CONCLUSIONS: These data confirm the association of douching and anal sex with various STD and suggest that sex during menses is associated with chlamydial infection.

Adult↗

PubMed1998

Heterosexual repertoire is associated with same-sex experience.

OBJECTIVE: The association of sexual repertoire with sexual preference, partnership and sociodemographic characteristics, and sexual history among white American (WA) and African-Americans (AA) is described. DESIGN: Cross-sectional computer-assisted telephone survey. METHODS: Seattle residents 18 to 39 years of age selected via random digit dialing; an additional sample of AA sampled from listed telephone numbers from census tracks with over 40% Aa. RESULTS: The study included 356 WA and 140 AA ever engaging in vaginal intercourse who answered questions regarding their usual sexual repertoire with their most recent opposite-sex partner. The 5% of WA engaging in vaginal, oral, and anal intercourse with their most recent opposite-sex partner were 2.7 times (95% CI: 0.9, 7.9) as likely to report nonmonogamy and 8.4 times (95% CI: 2.6, 27.2) as likely to report a history of same-sex partners. Persons reporting a history of both same- and opposite-sex partnerships were more likely than those with only opposite-sex partners to report engaging in anal and oral sex with their most recent opposite-sex partner regardless of gender (anal: women 24% vs. 4%, p < 0.001; men: 33% vs. 6%, p < 0.001; oral: women 95% vs. 74%, p = 0.03; men 89% vs. 78%, p = 0.4). Persons with a history of a same-sex partner were also more likely than those with only opposite-sex partners to have a nonmonogamous current relationship (WA: odds ratio [OR] = 2.3; 95% CI: 0.9, 5.7; AA: OR = 6.8; 95% CI: 0.6, 338) to engage in sex during menses (WA: OR = 1.9; 0.7, 5.4; AA: 9.6; 1.0, 4.6) and to have more sex partners in their life (WA: p = 0.002; AA: p = 0.07). CONCLUSIONS: Diverse sexual repertoires are associated with other risk behaviors putting the individual at high risk of acquiring or transmitting a sexually transmitted diseases (STD).

Adolescent↗

PubMed1998

Cytotoxicity of hemolytic, cytotoxic necrotizing factor 1-positive and -negative Escherichia coli to human T24 bladder cells.

Approximately one-half of Escherichia coli isolates from patients with cystitis or pyelonephritis produce the pore-forming cytotoxin hemolysin, a molecule with the capacity to lyse erythrocytes and a range of nucleated cell types. A second toxin, cytotoxic necrotizing factor 1 (CNF1), is found in approximately 70% of hemolytic, but rarely in nonhemolytic, isolates. To evaluate the potential interplay of these two toxins, we used epidemiological and molecular biologic techniques to compare the cytotoxicity of hemolytic, CNF1(+), and CNF1(-) cystitis strains toward human T24 bladder epithelial cells in vitro. A total of 29 isolates from two collections of cystitis-associated E. coli were evaluated by using methylene blue staining of bladder monolayers at 1-h intervals after inoculation with each strain. Most (20 of 29) isolates damaged or destroyed the T24 monolayer (less than 50% remaining) within 4 h after inoculation. As a group, CNF1(+) isolates from one collection (11 strains) were less cytotoxic at 4 h than the CNF1(-) strains in that collection (P = 0.009), but this pattern was not observed among isolates from the second collection (18 strains). To directly evaluate the role of CNF1 in cytotoxicity of hemolytic E. coli without the variables present in multiple clinical isolates, we constructed mutants defective in production of CNF1. Compared to the CNF1(+) parental isolates, no change in cytotoxicity was detected in these cnf1 mutants. Our results indicate that CNF1 does not have a detectable effect on the ability of hemolytic E. coli to damage human bladder cell monolayers in vitro.

Bacterial Toxins↗

PubMed1997

The role of early HIV infection in the spread of HIV through populations.

The combination of two factors gives early HIV infection an especially strong influence on transmission dynamics: (a) increased transmission probabilities and (b) increased transmission potential of partners infected during this period. Most attention has been focused on the first factor because it fits the way we usually think about risk factors affecting individuals. The second factor acts not on individuals, but across chains of transmission. It is missed by models with constant partnership formation rates over an individual's life or with random mixing. It cannot be assessed from available data collected from individuals. Its assessment requires data from both individuals in a partnership. We demonstrate that this second effect can be so strong that early infection can dominate transmission dynamics even when transmission probabilities are only modestly increased. This second effect is not directly parameterized in our models but arises from two realistic types of temporal variation in partnership formation: (a) Partnership formation rates vary by age with preferential partnership formation in one's own age group, and (b) individuals of any age can experience transient periods of high-risk partnership formation. In a model with only the age-related effect, early infection is observed to dominate transmission dynamics when 20% of transmissible virus is allocated to the first 6 weeks of infection, 7% to middle infection, and 73% to late infection. This domination occurs both early in the course of an epidemic and later when endemic infection levels have been reached. When the second effect is added, early infection is seen to dominate transmission in a model allocating 10% of transmissible virus to the first 6 months, 40% to middle infection, and 50% to late infection. In this model, transmission probabilities during early infection are only 4.17 times those of middle infection and half those of late-stage infection.

Age Factors↗

PubMed1997

Discovery of disseminated J96-like strains of uropathogenic Escherichia coli O4:H5 containing genes for both PapG(J96) (class I) and PrsG(J96) (class III) Gal(alpha1-4)Gal-binding adhesins.

The pyelonephritis-associated adhesin gene papG of Escherichia coli occurs in three variants. Whereas the class II and class III variants are common among human urinary tract infection isolates, the class I allele, despite being the first cloned, has previously been found only in source strain J96. Five strains have been discovered from geographically diverse locales that, like J96, contain both the class I and class III papG alleles. One strain caused bacteremia, whereas 4 caused cystitis. Like J96, all 5 had group III capsule genes, expressed the H5 flagellar antigen and the F13 fimbrial antigen, and exhibited similar genomic patterns and virulence factor profiles. These findings demonstrate that the class I papG allele is not unique to J96 but is present in a group of extraintestinal isolates of E. coli O4:H5 that represent a disseminated virulent clonal group.

Adhesins, Escherichia coli↗

PubMed1997

Transmission of uropathogens between sex partners.

Epidemiologic evidence and several case reports suggest that Escherichia coli causing urinary tract infection (UTI) may be transmitted between sex partners. In order to test this hypothesis, urinary, vaginal, and fecal E. coli isolates from 19 women with UTI were compared with E. coli found in random initial voids from their most recent male sex partner. E. coli was isolated from 4 of 19 male sex partners. In each case, the E. coli isolated from the man was identical by pulsed-field gel electrophoresis and bacterial virulence profile to the urinary E. coli from his sex partner.

Adult↗

PubMed1997

Association of recurrent vaginal candidiasis and secretory ABO and Lewis phenotype.

The relationship between ABO-Le secretor phenotype and susceptibility to recurrent idiopathic vulvovaginal candidiasis (RVVC) was investigated. ABO and Lewis blood typing was done for 38 women with RVVC (case-patients) and for women in 2 control groups, consisting of 58 healthy women, who were friends identified by case-patients, and 38 race-matched, healthy hospital employees. The 3 groups were similar with regard to age and race. There was no difference in the distribution of ABO phenotype between case-patients and controls. Case-patients were more likely than members of either control group to have Le(a+ b-) (nonsecretor) rather than Le(a- b+) (secretor) blood type. With combined nonsecretor Le(a+ b-) phenotype and absence of the Lewis gene Le(a- b-), the relative risk of chronic recurring vulvovaginal candidiasis was 2.41-4.39, depending on the analysis technique and control group. In conclusion, there is an increased frequency of ABO-Le nonsecretor status among women with RVVC.

ABO Blood-Group System↗