Prevalence of Chlamydia trachomatis and other micro-organisms in women seeking abortions in Pittsburgh, Pennsylvania, United States of America

Periodic health examination, 1996 update: 2. Screening for chlamydial infections. Canadian Task Force on the Periodic Health Examination

OBJECTIVE

To update the 1984 recommendations of the Canadian Task Force on the Periodic Health Examination on the routine screening of asymptomatic patients for infection with Chlamydia trachomatis.

OPTIONS

Screening, with the use of culture or nonculture tests, of the general population, of certain high-risk groups or of all pregnant women; or no routine screening.

OUTCOMES

Rates of asymptomatic and symptomatic chlamydial infection, perinatal complications, longterm complications of infection (i.e., pelvic inflammatory disease, infertility and ectopic pregnancy), coinfection with other sexually transmitted diseases, disease spread, hospital care, complications of therapy and costs of infection and of screening.

EVIDENCE

Search of MEDLINE for articles published between Jan. 1, 1983, and Dec. 31, 1995, with the use of the major MeSH heading "chlamydial infections," references from recent review articles and recommendation by other organizations.

VALUES

The evidence-based methods of the Canadian Task Force on the Periodic Health Examination were used. Advice from reviewers and experts and recommendations of other organizations were taken into consideration. Prevention of symptomatic disease and decreased overall costs were given high values.

BENEFITS, HARMS AND COSTS

The greatest potential benefits of screening asymptomatic patients for chlamydial infections are the prevention of complications, especially infertility and perinatal complications, and the prevention of disease spread. There is no evidence that screening of the general population for chlamydial infections leads to a reduction in complications, and screening may increase costs. However, there is evidence that annual screening of selected high-risk groups and of pregnant women during the first trimester is beneficial in preventing symptoms and reducing the overall cost resulting from infection.

RECOMMENDATIONS

There is fair evidence to support screening and treatment of pregnant women during the first trimester (grade B recommendation) as well as annual screening and treatment of high-risk groups (sexually active women less than 25 years of age, men or women with new or multiple sexual partners during the preceding year, women who use nonbarrier contraceptive methods and women who have symptoms of chlamydial infection: cervical friability, mucopurulent cervical discharge or intermenstrual bleeding; grade B recommendation). There is fair evidence to exclude routine screening of the general population (grade D recommendation).

VALIDATION

These recommendations are similar to those of the US Preventive Services Task Force and the US Centers for Disease Control and Prevention, Atlanta.

SPONSOR

These guidelines were developed and endorsed by the Canadian Task Force on the Periodic Health Examination, which is funded by Health Canada and the National Health Canada and the National Health Research and Development Program. The principal author (H.D.D.) was supported in part by the Ontario Ministry of Health and the Canadian Infectious Diseases Society Lilly Fellowship.

Chlamydial infection among females attending an abortion clinic: prevalence and risk factors

To determine the prevalence of Chlamydia trachomatis infection and the epidemiologic risk factors for chlamydial infection in the Quebec City region, screening was done with an enzyme immunoassay in 920 females who attended an abortion clinic between November 1985 and June 1986. The organism was detected in 105 (11.4%) of the patients. After adjustment for confounding variables, four variables were found to be independent risk factors for chlamydial infection: age 24 years or less (prevalence ratio 3.0 [p less than 0.001]), two or more sexual partners during the previous year (prevalence ratio 1.8 [p = 0.001]), no contraception or the use of a nonbarrier method (prevalence ratio 1.9 [p = 0.030]) and living in an urban area (prevalence ratio 1.6 [p = 0.046]). The results confirm that chlamydial infection is prevalent in this population. The identified risk factors may prove useful in determining the target population for screening programs.

Morbidity after termination of pregnancy in first trimester

The outcome of termination of pregnancy was observed in relation to the preoperative clinical and microbiological findings in 167 women attending a day care abortion unit in Liverpool. Before termination, Chlamydia trachomatis was isolated from the cervix of 19 (11%) of the patients and high counts (greater than 10(4) colour changing units (ccu) per ml of specimen) of mycoplasmas were found in 30 (18%). Coexistent infections with chlamydiae and high counts of mycoplasmas occurred in only seven (4%) women. Trichomonas vaginalis, yeasts, or pathogenic bacteria were found in vaginal swabs from 30 (18%) women. After undergoing termination, seven (4%) women developed pelvic inflammatory disease (PID), five (71%) of whom had yielded C trachomatis before undergoing termination. A further 13 (8%) patients developed minor morbidity of the upper genital tract; high count mycoplasmal infection had been found in seven (54%) and chlamydial infection in three (23%) of these women before termination. In contrast, C trachomatis had been isolated from only 11 (8%) and high counts of mycoplasmas from 23 (16%) of the 147 women who had uneventful recoveries after undergoing termination. No correlation was apparent between the presence of vaginal pathogens before termination and the development of untoward sequelae postoperatively. Neither the history nor clinical examination before termination would have indicated that chlamydial or mycoplasmal infections were present, or that postoperative complications were likely to occur. Abnormal cervical cytology, however, was found in 86 (52%) of women overall, including 15 (79%) of the 19 women with chlamydial infection.