Detection of Chlamydia trachomatis: A study of the direct immunofluorescence technique and a review of diagnostic limitations

Because of the high prevalence of Chlamydia trachomatis in adolescent females and the high cost of chlamydia cultures, we evaluated the use of the direct fluorescein conjugated monoclonal antibody test (DFA) in diagnosing C. trachomatis in adolescent females. Chlamydia trachomatis was found in 37 (20.1%) of 184 cultures. The sensitivity of the direct smear as compared with the culture was 89% and the specificity was 99%. The results of recent studies of the DFA and chlamydiazyme tests are reviewed as well as the problems in comparing techniques.     

Asymptomatic Lymphogranuloma Venereum in Men who Have Sex with Men,United Kingdom

We investigated prevalence of lymphogranuloma venereum (LGV) among men who have sex with men who were tested for chlamydia at 12 clinics in the United Kingdom during 10 weeks in 2012. Of 713 men positive for Chlamydia trachomatis, 66 (9%) had LGV serovars; 15 (27%) of 55 for whom data were available were asymptomatic.     

Urinary leukocyte esterase screening for asymptomatic sexually transmitted disease in adolescent males

The objective of this study was to evaluate the effectiveness of urinary leukocyte esterase on random urine specimens as a screening test for chlamydial and gonococcal urethral infections in asymptomatic males. Random urine specimens were obtained on 106 consecutive asymptomatic adolescent males during intake physical examination at a residential vocational training program. Results of urinary leukocyte esterase were compared to those of urethral cultures for Chlamydia trachomatis and Neisseria gonorrhoeae. Five subjects had positive chlamydia cultures, three subjects had positive gonococcal cultures, and one patient had positive cultures for both organisms. Sixteen subjects had leukocyte esterase tests reported as "trace" or greater. When compare to positive culture results for either Chlamydia or gonorrhea, urinary leukocyte esterase activity had a sensitivity of 78%, specificity of 91%, and positive predictive value of 44%. A random urine specimen for urinary leukocyte esterase activity is a cost-effective screening method for chlamydial and gonococcal urethral infections in asymptomatic adolescent males.     

An evaluation of urethral smear by Papanicolaou stain in men with urethritis

The objective of this study was to evaluate the usefulness of a Papanicolaou stained urethral smear (Pap smear) to identify sexually transmitted disease (STD) pathogens in men with urethritis. Specimens from the endourethra were obtained for Chlamydia trachomatis and Neisseria gonorrhoeae cultures, a Gram stain, and a Pap smear in 24 symptomatic men aged 16–22 years. All Pap smears were read independent of the culture results. Based on the laboratory techniques employed, nine subjects had gonococcal urethritis (GU), and 11 had nongonococcal urethritis (NGU). Four subjects with GU had concomitant infection with another STD pathogen(s). Papanicolaou smear alone identified four different pathogens in 16 subjects, chlamydia in ten, trichomonads in two, intracellular diplococci in two, multinucleate giant cells of herpes in one, and chlamydia and trichomonad together in one. Out of 11 chlamydia-positive Pap smears, three had a positive culture. One subject had a positive chlamydia culture and a negative Pap smear. Two subjects with intracellular diplococci on Pap smear had culture-confirmed gonorrhea. The Pap smear was useful in identifying some of the different pathogens in NGU, especially trichomonads and herpes, not recoverable by commonly used techniques and in the diagnosis of concomitant infection by more than one STD pathogen in GU. Adding the Pap smear to the diagnostic tests for urethritis increased the etiologic diagnoses from 37.5% to 79%.     

First catch urine sediment for Chlamydia trachomatis and Neisseria gonorrhoeae culture in adolescent males with pyuria

Traditionally, only symptomatic males or those with a history of exposure are tested for sexually transmitted diseases (STDs). Since urethral infections with Chlamydia trachomatis and Neisseria gonorrhoeae are frequently asymptomatic, a practical, sensitive, and acceptable screening method is desirable. Fifty sexually active males with pyuria (age 13 to 22 years old) diagnosed with 1+ or 2+ leukocyte esterase (LE) dipstick on first catch urine (FCU) were further evaluated by culture of urethral swabs and centrifuged FCU samples for N. gonorrhoeae and C. trachomatis. Eighty-six percent had one or more positive cultures: 17 (34%) N. gonorrhoeae, 18 (36%) C. trachomatis, and 8 (16%) both organisms. FCU culture for N. gonorrhoeae had a 100% sensitivity, specificity, and positive and negative predictive value when compared to urethral swab cultures. FCU culture for C. trachomatis had a 32% sensitivity, 95% specificity, 89% positive predictive value, and a 53% negative predictive value compared to urethral culture. On the basis of the results of this study, one urethral swab can be eliminated when evaluating male adolescents for urethritis by using spun FCU culture for N. gonorrhoeae. Continued efforts should be made to develop optimal tests to detect STDs which are reliable and encourage compliance in this high-risk group.     

Performance of urine leukocyte esterase in asymptomatic male youth: Another look with nucleic acid amplification testing as the gold standard for Chlamydia detection

PurposeTo re-evaluate the sensitivity and specificity of leukocyte esterase (LE) for screening adolescent and young adult males for Chlamydia trachomatis using a nucleic acid amplification test (NAAT) as the gold standard.MethodsThis study was conducted at two Massachusetts Department of Youth Services sites and one Job Corps site. Recently admitted asymptomatic sexually active male youth aged 14 to 25 years (mean 16.6 years) were recruited between January 2001 and July 2003 (N = 1008). Participants provided first part voided urine specimens for testing with LE and Chlamydia NAAT. The sensitivity, specificity, and positive and negative predictive value of urine LE for identification of Chlamydia infection were determined using NAAT as the gold standard.ResultsFifty-seven (5.7%) participants were infected with Chlamydia as defined by a positive NAAT. Defining trace + as the LE cut point resulted in sensitivity and specificity of 57.9% and 78.3%, respectively. Defining 1+ as the cut point resulted in sensitivity and specificity of 47.4% and 96.1%, respectively.ConclusionsUrine leukocyte esterase is a moderately sensitive method to screen for Chlamydia. Nevertheless, a substantial proportion of infections are not detected with LE screening. When feasible, urine NAAT provides a much more sensitive and equally noninvasive method of detecting Chlamydia. However, if LE is used as an initial screen followed by NAAT confirmation of LE positive samples, we recommend using trace LE as the cut point for positive results.     

Screening asymptomatic adolescent males for chlamydia

Ninety-seven asymptomatic 16–21-year-old sexually active adolescent males were evaluated for gonorrhea and chlamydia by culture, chlamydia enzyme immunoassay, and an analysis of a random urine sample for pyuria using centrifuged urine and urine cytometer. The incidence of gonorrhea was 5.3% and chlamydia by culture 12.3%. Immunoassay was superior in sensitivity and specificity (75% and 99%, respectively) to centrifuged urine (sensitivity 58%, specificity 92%) or urine cytometer (58% and 91%) in identifying asymptomatic chlamydia urethritis. Chlamydia enzyme immunoassay is an acceptable, more rapid, and less expensive alternative to culture. The absence of pyuria in asymptomatic males cannot be assumed to indicate the absence of a sexually transmitted disease.     

样品库PCR法检测大学生沙眼衣原体感染状况的研究

目的 了解大学中沙眼衣原体((Chlamydia Trachomatis,CT)感染状况,探索有效的CT筛查方法,为制定中国青少年中的STDs的预防措施提供科学依据。方法 于1999年在北京某综合性大学学生中,随机抽取2050人,进行间卷调查并调查人群中的Cr感染率。结果 在1935份有效尿样中,共检出阳性3例,检出率为1.6％。结论在低CT感染率人群中进行筛查,样品库(Pooling)法为一行之有效的筛查方法,并提示在大学生中,生殖健康之重点应为安全性知识、性道德的宣传。     

Prevalence and correlates of Chlamydia infection in Canadian street youth.

PURPOSE: To determine the prevalence and correlates of Chlamydia trachomatis in Canadian street youth. METHODS: A cross-sectional study of street youth between the ages of 15-24 years was conducted over a 9-month period in seven large urban centers across Canada. Youth were recruited through "drop-in" centers, outreach work, and mobile vans in each city. Information was collected through a nurse-administered questionnaire. Youth were asked to provide urine to test for chlamydia trachomatis by polymerase chain reaction. Separate logistic regression models were run for males and females controlling for age. RESULTS: The prevalence rate of chlamydia was 8.6% in 1355 youth (95% CI = (7.1%, 10.1%)). Higher prevalence rates were found in females than in males (10.9% vs. 7.3%, respectively) and in Aboriginal youth than in non-Aboriginal youth (13.7% vs. 6.6%, respectively). Four variables were associated with increased risk of chlamydia infection in females: Aboriginal status; self-perceived risk; having no permanent home; and having been in foster care. One predictor of chlamydia for males was having had a social worker. CONCLUSIONS: A high prevalence of chlamydia was found in this vulnerable population in comparison to other Canadian youth. Having been in foster care and having had a social worker were found to have a strong association with chlamydia.     

Chlamydia trachomatis testing sensitivity in midstream compared with first-void urine specimens

PURPOSE

Traditionally first-void urine specimens are used to test for Chlamydia trachomatis. In contrast, midstream urine specimens are traditionally recommended for microscopy and culture of presumptive bacterial urinary tract infections. The ability to test for both C trachomatis and urinary tract infection on a single midstream urine specimen would greatly aid clinical practice, as an urinary tract infection is an extremely common complaint in primary care. This study set out to determine how well positive C trachomatis results obtained on first-void specimens would correlate with positive findings in matched midstream specimens.

METHODS

One hundred women with a first-void urine specimen positive for C trachomatis also provided midstream specimens for comparison. All specimens had C trachomatis testing performed using a DNA detection method.

RESULTS

Of the 100 eligible participants with a first-void specimen positive for C trachomatis, 96 (96%) also had a positive midstream specimen (95% exact confidence limits, 90.1%, 98.9%).

CONCLUSIONS

These results suggest that by using newer nucleic acid amplification techniques (NAATs), timing of specimen collection is not so important in testing for C trachomatis as previously thought. The sensitivity of NAAT testing on midstream urine specimens in women is sufficiently equivalent to testing on first-void specimens to consider in clinical practice and research settings where first-void specimens have formerly been collected.     

Screening for sexually transmitted infections among economically disadvantaged youth in a national job training program.

PURPOSE: To evaluate results of screening for syphilis, gonorrhea, and chlamydia among youth in a federally funded job training program. METHODS: Data were evaluated from medical records of 12,881 randomly selected students in 54 U.S. job training centers during 1996. The intake medical evaluation includes serologic testing for syphilis. The policy was for females to receive a pelvic examination with gonorrhea and chlamydia testing and for males to be first screened with a urine leukocyte esterase (LE) assay, with follow-up gonorrhea and chlamydia testing for those with positive LE results. RESULTS: Adjusting for our sampling strategy, among females, an estimated 9.2% had a positive chlamydia test, 2.7% a positive gonorrhea test, and 0.4% had a positive syphilis test. Gonorrhea and chlamydia rates among females were highest in African-American followed by Native American students. Chlamydia infection was most common in younger women < or = 17 years of age. An estimated 0.1% of males had a positive syphilis test, and 4.8% of males a positive urine LE test. Of 103 LE-positive males tested for gonorrhea and chlamydia, only 27 (26%) had a positive test for one of these STDs. CONCLUSIONS: Our study supports routine screening of adolescents for gonorrhea and chlamydia, including those youth from socioeconomically disadvantaged backgrounds. Because individuals from such backgrounds may not regularly interact with traditional clinical health care systems, screening and treatment should be offered in alternative settings, such as the job training program described in this study.     

Barriers to screening sexually active adolescent women for chlamydia: a survey of primary care physicians.

PURPOSE: To determine the proportion of primary care physicians who screen sexually active teenage women for chlamydia and to determine demographic factors, practice characteristics, and attitudes associated with chlamydia screening. METHODS: We obtained a random sample of 1600 Pennsylvania physicians from the American Medical Association masterfile, stratified to include at least 40% women and equal numbers of family physicians, internists, obstetricians/gynecologists, and pediatricians. In January 1998, physicians received mailed questionnaires; nonrespondents received two follow-up mailings. Physician characteristics associated with chlamydia screening were determined using bivariate and logistic regression analyses. RESULTS: Only one-third of physicians responded that they would screen asymptomatic, sexually active teenage women for chlamydia during a routine gynecologic examination. In multivariate analysis, physicians were significantly (p <.05) more likely to screen if they were female (43% vs. 24%), worked in a clinic versus solo practice (60% vs. 18%), worked in a metropolitan location (46% vs. 26%), or had a patient population > or = 20% African-American (54% vs. 25%). Attitudes associated with screening included the belief that most 18-year-old women in their practice were sexually active (36% vs. 12%), feeling responsible for providing information about the prevention of sexually transmitted diseases to their patients (42% vs. 21%), or knowing that screening for chlamydia prevents pelvic inflammatory disease (37% vs. 13%). Physicians were less likely to screen if they believed that the prevalence of chlamydia was low (10% vs. 41%). CONCLUSIONS: A majority of physicians do not adhere to recommended chlamydia screening practices for teenage women. Interventions to improve chlamydia screening might target physicians who are male, in private practice, or who practice in rural areas, and should focus on increasing awareness of the prevalence of chlamydia and benefits of screening.     

Acute Epididymitis: Etiology and Therapy

Fifty patients with acute epididymitis were evaluated prospectively by history, examination, and microbiologic studies, including cultures for aerobes, anaerobes, N. gonorrhoeae, Chlamydia trachomatis, and Ureaplasma urealyticum. E. coli was the predominant pathogen isolated from the urine of men over 35 years old and C. trachomatis and N. gonnorrheae were the predominant pathogens isolated from the urethra of men under 35. The etiologic role of E. coli and C. trachomatis was confirmed by isolation from epididymal aspirates from a high proportion of men with positive urine of urethral cultures for these agents. C. trachomatis epididymitis accounted for two thirds of “idiopathic epididymitis” in men, and was often associated with oligozoospermia. Of nine female sexual partners of men with C. trachomatis infection, six had antibody to C. trachomatis, of whom two had positive cervical cultures for this organism, and the others had nongonococcal pelvic inflammatory disease. Antibiotic therapy with tetracycline was effective for the treatment of men with C. trachomatis epididymitis, and should be offered to their female sex partner.     

Prevalence of genital chlamydia and mycoplasma infection in couples attending a male infertility clinic

To investigate the prevalence of genital mycoplasma (Ureaplasma urealyticum andMycoplasma hominis) andChlamydia trachomatis infections in infertile and fertile couples, 135 infertile couples from a male infertility clinic and 88 fertile couples from a prenatal care clinic were randomly screened. Semen, urethral and cervical smears were cultured for genital mycoplasma and chlamydia. Antichlamydia IgA, IgG and IgM antibodies were tested in blood and semen. Although the overall prevalence ofUreaplasma urealyticum was higher than that ofMycoplasma hominis, the prevalence ofMycoplasma hominis was significantly higher in the infertile men and women. The prevalence ofChlamydia trachomatis, positive culture was higher in infertile couples, but this difference was not significant. The prevalence of serum-specific IgG was significantly higher in infertile than in fertile women (11.9 vs 3.4%,p<0.05). Specific semen IgA was significantly higher in infertile than in fertile men (8.9 vs 1.1%,p<0.015). A low rate of concordance between partners was found inMycoplasma andChlamydia culture, and in the same patient between seminal IgA and urethral culture. In conclusion it is necessary to check both culture and serology findings in both partners.     

Chlamydia trachomatis Infection Among Women Reporting Sexual Activity With Women Screened in Family Planning Clinics in the Pacific Northwest, 1997 to 2005

Objectives. We sought to define Chlamydia trachomatis positivity among women who report sexual activity with women, a population for which sparse data on this infection are available and for whom health disparities including challenged access to comprehensive sexual and reproductive health services, have been reported.Methods. We analyzed data from 9358 family planning clinic visits with C trachomatis tests among women aged 15 to 24 years who reported sexual activity within the past year exclusively with women (WSW) or with men and women (WSMW), in the Region X Infertility Prevention Project. Characteristics were compared with women who reported sexual activity exclusively with men (WSM).Results. C trachomatis positivity among both WSW and WSMW was 7.1%, compared with 5.3% among WSM. Behavioral risks were more commonly reported by WSW and WSMW, compared with reports by WSM. Risks for C trachomatis positivity were comparable across groups and included younger age, non-White race, behavioral risks, and clinical signs.Conclusions. Higher C trachomatis positivity among women reporting same-sex sexual behavior supports investigation into potential explanatory factors, including sexual behaviors, biological susceptibility, routine C trachomatis screening disparities, sexual identity disclosure, and sexual network assessment.Chlamydia trachomatis is the most common bacterial sexually transmitted infection (STI) in the United States, with an estimated 4 million to 5 million cases reported annually to the Centers for Disease Control and Prevention (CDC).¹ C trachomatis has a major impact on women''s sexual and reproductive health. Untreated infections can lead to pelvic inflammatory disease (PID), tubal infertility, and chronic pelvic pain. Because the majority of infections in women are asymptomatic and do not usually cause visible signs of cervicitis, CDC and the US Preventive Services Task Force recommend C trachomatis screening at least annually for all women aged 24 years and younger.^2,3 In 1988, widespread screening for C trachomatis began in Alaska, Idaho, Oregon, and Washington (US Public Health Service Region X) in family planning clinics. This became the first chlamydia prevalence monitoring surveillance system to use standardized testing and data collection, and was the basis for the CDC''s Infertility Prevention Project (IPP).⁴According to the 2002 National Survey of Family Growth, 11% of US women aged 15 to 44 years reported same-sex sexual behavior in their lifetime.⁵ Despite the fact that same-sex sexual behavior is not infrequent among women in the United States and despite the widespread prevalence of C trachomatis, little data at the clinic, community, or population levels are available that describe the prevalence of C trachomatis among US women. Moreover, numerous studies support that more than 90% of women who self-identify as lesbian report a sexual history with men.⁶ Prior studies indicate that women who report same-sex sexual behavior, including exclusively same-sex behavior, acquire STIs, including genital types of human papillomavirus (HPV), HIV, genital herpes, and trichomoniasis.^7–13 Moreover, bacterial vaginosis occurs commonly among women who report sexual activity with women, and there is a high degree of concordance among monogamous same-sex couples, suggesting a potential role for sexual transmission in this group.¹⁴ These observations emphasize the need for health care providers and public health advocates to address the sexual and reproductive health care needs of this group of women in a comprehensive and informed manner.The purpose of our study was to describe the prevalence of and risks associated with chlamydial infection among women aged 15 to 24 years who reported same-sex sexual behavior and attended family planning clinics in the Region X IPP during the years 1997 through 2005. Since the project''s inception in 1988, universal screening for C trachomatis has been recommended for family planning female clients in this age group.     

Urinary Symptoms in Adolescent Females: STI or UTI?

PurposeTo determine if urinary symptoms or urinary tract infections (UTI) were associated with sexually transmitted infections (STI) and which history, clinical, and laboratory findings could distinguish these infections in symptomatic women.MethodsA cross-sectional sample of 296 sexually active females aged 14–22 years attending a hospital-based teen health center or emergency department were recruited. Genitourinary symptoms, medical and sexual history, and urinalysis results were recorded. STI was defined as a vaginal swab positive for Trichomonas vaginalis or urine nucleic acid amplification test positive for Neisseria gonorrheae or Chlamydia trachomatis. A urine culture with >10,000 colonies of a single pathogen was considered a positive UTI.ResultsIn the full sample, prevalence of UTI and STI were 17% and 33%, respectively. Neither urinary symptoms nor UTI was significantly associated with STI. Further analyses are reported for the 154 (51%) with urinary symptoms: Positive urine leukocytes, more than one partner in the last three months and history of STI predicted STI. Urinalysis results identified four groups: (1) Normal urinalysis—67% had no infection; (2) Positive nitrites or protein—55% had UTI; (3) Positive leukocytes or blood—62% had STI; and (4) Both nitrites/protein and leukocytes/blood positive—28% had STI and 65% had UTI. Those without a documented UTI were more likely to have trichomoniasis than those with a UTI, and 65% of those with sterile pyuria had STI, mainly trichomoniasis or gonorrhea.ConclusionsAdolescent females with urinary symptoms should be tested for both UTI and STIs. Urinalysis results may be helpful to direct initial therapy.     

Malaria parasitemia in healthy Africans in North Mara,Tanzania

Peripheral blood smears were examined for asymptomatic malaria parasitemia among 406 objectively healthy subjects in North Mara, Tanzania. A total of 33(8.1%) of subjects were found to have asymptomatic malaria parasitemia. Prevalence rates for parasitemia were highest among the youngest age groups and lowest in those 35 years of age and older. Of the 33 positive smears, 21 (63.6%) contained Plasmodium falciparum, 9(27.2%) plasmodium malariae and 3(9.2%) mixed infections of the two. General population surveys for asymptomatic malaria parasitemia in North Mara have shown much higher prevalence rates than those found in the present study. The lower prevalence rates in this study are accounted for by the fact that the population sample consisted of subjects determined to be healthy by objective criteria and lacking hepatomegaly and splenomegaly. The absence of splenomegaly and hepatomegaly in this group suggests that they represent a portion of the population who have already developed significant immunity levels to malarial infections.     

Ultraviolet light disinfection of hospital water for preventing nosocomial Legionella infection: a 13-year follow-up.

BACKGROUND AND OBJECTIVE: CDC has estimated that 23% of Legionella infections are nosocomial. When a new hospital was being constructed and a substantial increase in transplantation was anticipated, an ultraviolet light apparatus was installed in the water main of the new building because 27% of water samples from taps in the old hospital contained Legionella. This study reports the rate of nosocomial Legionella infection and water contamination since opening the new hospital. METHODS: Charts of all patients with positive Legionella cultures, direct immunofluorescent antibody (DFA), or urine antigen between April 1989 and November 2001 were reviewed. Frequencies of DFAs and urine antigens were obtained from the laboratory. RESULTS: None of the 930 cultures of hospital water have been positive since moving into the new building. Fifty-three (0.02%) of 219,521 patients had a positive Legionella test; 41 had pneumonia (40 community acquired). One definite L. pneumophila pneumonia confirmed by culture and DFA in August 1994 was nosocomial (0.0005%) by dates. This patient was transferred after prolonged hospitalization in another country, was transplanted 11 days after admission, and developed symptoms 5 days after liver transplant. However, tap water from the patient's room did not grow Legionella. Seventeen (2.5%) of 670 urine antigens were positive for Legionella (none nosocomial). Thirty-three (1.2%) of 2,671 DFAs were positive, including 7 patients (21%) without evidence of pneumonia and 6 (18%) who had an alternative diagnosis. CONCLUSION: Ultraviolet light usage was associated with negative water cultures and lack of clearly documented nosocomial Legionella infection for 13 years at this hospital.     

Significant bacteriuria among the mentally retarded. Identification and antibiotic sensitivity of isolates.

A study was carried out to determine the prevalence of significant bacteriuria in a mentally retarded population. With 100,000 or more bacteria per ml. of urine used as a criterion for significant bacteriuria, 24 of 665 persons studied were considered to have significant bacteriuria for an overall prevalence rate of 3.6%. Seventeen of the 24 positive urine cultures were either from clean catch or catheter specimens. All patients undergoing catheterization were found to have significant bacteriuria. The individual prevalence rates of significant bacteriuria for males and females were 1.7 and 5.6 respectively. In females, an increasing prevalence of bacteriuria was found primarily in the 55-64 age group. The predominant bacteria isolated from bacteriuric patients were gram-negative bacilli, Escherichia coli, being isolated in 50% of all positive cultures. Antiobiotic sensitivity patterns of the isolates indicated a high degree of in vitro resistance to both ampicillin and cephalothin.     

Urine-based testing for Chlamydia trachomatis among young adults in a population-based survey in Croatia: Feasibility and prevalence

Background  

We assessed the feasibility of collecting urine samples for testing on genital Chlamydia trachomatis infection in a population-based survey, and prevalence of this infection among young people aged 18-25 in Croatia. In Croatia, as in the other countries of Eastern Europe, there is a lack of data on prevalence of C trachomatis in the general population, including young adults.