Treatment of men with urethritis negative for Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum and Ureaplasma urealyticum

OBJECTIVE: Some patients with symptomatic non-gonococcal urethritis (NGU) are negative for Chlamydia trachomatis, mycoplasmas and ureaplasmas. The optimal antimicrobial chemotherapy for such NGU has not fully been elucidated, though many studies of antimicrobial chemotherapies for C. trachomatis-positive NGU have been performed. We assessed the efficacy of antimicrobial agents that are active against C. trachomatis on non-mycoplasmal, non-ureaplasmal and non-chlamydial NGU (NMNUNCNGU). METHODS: One hundred men whose first-pass urine samples were negative for C. trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum were treated with levofloxacin, gatifloxacin, minocycline, or clarithromycin for 7 days. Urethritis symptoms and the presence of polymorphonuclear leukocytes (PMNL) in urethral smears were assessed before and after treatment. RESULTS: Eighty-eight (88.0%) of 100 men with NMNUNCNGU showed no signs of urethral inflammation after treatment, but two men complained of some symptoms of urethritis. Twelve (12.0%) of 100 men had significant numbers of PMNL in urethral smears, but five of these 12 men had no symptoms of urethritis. The efficacy for normalization of urethral smears was 90.7% for clarithromycin, 89.7% for levofloxacin, 87.5% for gatifloxacin, and 75.0% for minocycline. The 12 men who showed signs of urethral inflammation were retreated with levofloxacin, gatifloxacin, minocycline or clarithromycin for an additional 7 days. The 10 men who returned after the second treatment had negative urethral smears. CONCLUSION: Our present findings suggest that antimicrobial agents active against C. trachomatis are effective against NMNUNCNGU and that a 7-day treatment regimen with an appropriate antimicrobial agent may be sufficient to manage patients with NMNUNCNGU.     

Chlamydia trachomatis antigen can be detected in the urine sample of men with non-gonococcal urethritis

Summary We tested the first portion of voided urine (FVU) and urethral swab from 80 patients with nongonococcal urethritis (NGU) using a novel enzymeamplified immunoassay (IDEIA) for the detection of Chlamydia trachomatis antigen. Urine specimens were positive in all patients with positive urethral swabs (positive coincidence ratio, 100%) and in 6 of 54 patients with negative swabs (negative coincidence ratio, 88.9%). Our data suggest that FVU is suitable for the detection of Chlamydia trachomatis antigen using the IDEIA test in patients with NGU.     

Detection of Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum (biovar 1) and Ureaplasma urealyticum (biovar 2) in patients with non-gonococcal urethritis using polymerase chain reaction-microtiter plate hybridization

AIM: To use polymerase chain reaction (PCR)-microtiter plate hybridization assays to detect Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum (biovar 1) and Ureaplasma urealyticum (biovar 2) in first-voided urine specimens from patients with non-gonococcal urethritis (NGU). METHODS: A total of 153 male patients with NGU, who visited one of 24 clinics in Japan, were recruited for this study. All were examined using PCR-microtiter plate hybridization assays for the presence of M. genitalium, M. hominis, U. parvum (biovar 1) and U. urealyticum (biovar 2) in first-voided urine specimens. They were also examined for the presence of Chlamydia trachomatis. RESULTS: Of these 153 patients, 73 (47.7%) were positive for C. trachomatis. Overall, the prevalence was 17.0% for M. genitalium, 16.3% for U. urealyticum (biovar 2), 7.8% for U. parvum (biovar 1) and 2.6% for M. hominis. In the 80 patients with non-chlamydial NGU, the prevalence of M. genitalium, U. urealyticum (biovar 2), U. parvum (biovar 1) and M. hominis was 23.8%, 18.8%, 8.8% and 2.6%, respectively. CONCLUSIONS: This study shows the prevalence of mycoplasmas and ureaplasmas in NGU in Japan. M. genitalium and U. urealyticum (biovar 2) might be pathogens of NGU and could be associated with persistent and recurrent urethritis. When patients with NGU are treated, such pathogens should be taken into account. This PCR-microtiter plate hybridization assay provides a useful method for diagnosing NGU caused by M. genitalium and U. urealyticum (biovar 2).     

Assessment of Chlamydia trachomatis, Ureaplasma urealyticum, Ureaplasma parvum, Mycoplasma hominis, and Mycoplasma genitalium in semen and first void urine specimens of asymptomatic male partners of infertile couples

The purpose of this study was threefold: to compare semen and first void urine (FVU) specimens from asymptomatic infertile men for the detection of Chlamydia trachomatis, genital ureaplasma, and genital mycoplasma infections using in-house inhibitor-controlled polymerase chain reaction (PCR)-microtiter plate hybridization assay; to determine the prevalence of those organisms in infertile men in Tunisia; and to study the relationship between these bacteria and male infertility. Paired urine and semen specimens from 104 patients were examined by in-house PCR for the presence of DNA of Chlamydia trachomatis, genital ureaplasmas (Ureaplasma urealyticum and Ureaplasma parvum) and genital mycoplasmas (Mycoplasma hominis and Mycoplasma genitalium). Semen analysis was assessed according to the guidelines of the World Health Organization. Nominal scale variables, the Mann-Whitney test, and the Kruskal-Wallis nonparametric analysis of variance test were used for statistical analysis. There was a very high concordance (>95%) and a very good agreement (kappa > 0.9) between the detection of Chlamydia trachomatis, genital ureaplasmas, and Mycoplasma hominis in semen and corresponding FVU specimens. Our findings also show a high concordance (81.1%) and a good agreement (kappa = 0.79) between the detection of Mycoplasma genitalium in both specimens. C trachomatis, genital mycoplasmas, and genital ureaplasmas were found to be widespread among infertile male patients in Tunisia, as shown by their respective prevalences of 43.3%, 18.3%, and 14.4%. The mean values of seminal volume, sperm concentration, sperm viability, sperm motility, sperm morphology, and leukocyte count were not significantly related either to the detection of C trachomatis DNA or to that of genital ureaplasma or mycoplasma DNA in semen specimens. Using our in-house PCR, both semen and FVU were found to be sensitive diagnostic specimens for the detection of C trachomatis, ureaplasmas, and mycoplasmas. The FVU, a less invasive and self-collected specimen, can serve as a marker for the presence of these organisms in the genital tract and can be used as a reliable way of detecting asymptomatic carriers of infection.     

Prevalence of genital mycoplasmas and ureaplasmas in men younger than 40 years-of-age with acute epididymitis

Objectives: Acute epididymitis is often associated with urethritis. Mycoplasma genitalium and Ureaplasma urealyticum have been considered as pathogens of urethritis. The aim of the present study was to determine the prevalence of these microorganisms in men with acute epididymitis. Method: A total of 56 men younger than 40 years‐of‐age with acute epididymitis were enrolled in the present study between January 2006 and June 2010. First‐void urine specimens were subjected to culture of aerobic bacterial species, and examined for the presence of Chlamydia trachomatis, M. genitalium, M. hominis, U. parvum and U. urealyticum by polymerase chain reaction‐based assays. Urethral swabs were cultured for Neisseria gonorrhoeae. Results: The number and percentage of patients positive for each microorganism were as follows: Gram‐negative bacilli, 2% and 3.6%; Gram‐positive cocci, 23% and 41.1%; N. gonorrhoeae, 3% and 5.4%; C. trachomatis, 28% and 50.0%; M. genitalium, 5% and 8.9%; M. hominis, 6% and 10.7%; U. parvum, 6% and 10.7%; and U. urealyticum, 5% and 8.9%. Among 25 men with non‐chlamydial non‐gonococcal epididymitis, who were negative for Gram‐negative bacilli, M. genitalium or U. urealyticum was detected in one man each (4.0%), and M. hominis and/or U. parvum was detected in five (20.0%). Conclusion: In men younger than 40 years‐of‐age with acute epididymitis, C. trachomatis is a major pathogen. The prevalence of genital mycoplasmas and ureaplasmas are lower, and the role of genital mycoplasmas and ureaplasmas in the development of acute epididymitis remains to be determined.     

Relationship between Chlamydia trachomatis and Mycoplasma genitalium infection and pregnancy rate and outcome in Iranian infertile couples

The study was performed to investigate the prevalence of Chlamydia trachomatis and Mycoplasma genitalium in a population of infertile couples from Iran and how this relates to tubal factor infertility, pregnancy rate and outcome of pregnancy. Blood, semen and first‐void urine samples were obtained from 250 infertile couples and 250 fertile women as a control. Infertile couples were followed up after 24 months to determine diagnosis, referral for assisted conception, any pregnancy and pregnancy outcome. Data were analysed with regard to the results of (i) serological analysis for specific antibodies to C. trachomatis in serum; (ii) the presence of C. trachomatis and M. genitaliumDNA in first‐void urine; and (iii) in a semen sample of the male partner. Prevalence of C. trachomatis in our study population was comparable to other studies using similar methods and test specimens. No evidence of M. genitalium infection was found. Detection of C. trachomatis in one partner rarely correlated with infection in the other. The risk of tubal factor infertility and the probability of pregnancy and pregnancy outcome were unrelated to the results of serological tests for C. trachomatis antibodies or the presence of C. trachomatisDNA in first‐void urine of both partners and in a semen sample provided by the male.     

Mycoplasma genitalium in male urethritis: Diagnosis and treatment in Japan

Male urethritis is a common disease for urologists, with the most common pathogens being, Chlamydia trachomatis and Neisseria gonorrhoeae. When the tests fail to detect these pathogens, the presented urethritis is called non‐chlamydial non‐gonococcal urethritis. Mycoplasma genitalium is one of the pathogens for non‐chlamydial non‐gonococcal urethritis. The test for detecting M. genitalium, which is commercially available in Japan, is not accepted by the Japanese insurance system now. The detection rate of M. genitalium from patients with non‐gonococcal urethritis is 10–20% in Japan. Antimicrobial susceptibility testing for M. genitalium showed that macrolide has the strongest activity and the minimum inhibitory concentrations of tetracyclines were not substantially lower. Some kinds of fluoroquinolones, such as sitafloxacin and moxifloxacin, have stronger activities against M. genitalium. For non‐gonococcal urethritis, macrolides and tetracycline are recommended in some guidelines. In clinical studies, tetracyclines are less effective against M. genitalium than azithromycin, and azithromycin regimens including 1 g stat or 2 g stat are now recommended for urethritis with M. genitalium. However, macrolide‐resistant M. genitalium strains have recently emerged and are spreading worldwide. This macrolide‐resistance is closely related to mutations on the 23S rRNA gene. Sitafloxacin and moxifloxacin have shown good efficacies for M. genitalium in some clinical studies. If the azithromycin regimens fail, we must consider the use of fluoroquinolones, such as sitafloxacin, in Japan. The most important issues include the acceptance of M. genitalium examinations by the national insurance system and the individual treatment of C. trachomatis and M. genitalium in the not‐too‐distant future.     

Mutations in 23S rRNA and ribosomal protein L4 account for resistance in Chlamydia trachomatis strains selected in vitro by macrolide passage

Thirteen strains of Chlamydia trachomatis were exposed to subinhibitory concentrations of erythromycin (0.5 μg ml^?1), azithromycin (0.5 μg ml^?1) and josamycin (0.04 μg ml^?1) to select macrolide‐resistant mutants with serial passages. The C. trachomatis mutants presented with low‐level resistance to erythromycin, azithromycin and josamycin for which a 16‐fold increase, a 16‐fold increase and an 8‐fold increase respectively in the minimal inhibitory concentration (MICs) for the mutant strains compared with the MIC for the susceptible strains were found. The results of chemosensitivity showed that josamycin had the highest susceptibility rate compared with erythromycin and azithromycin in the treatment of C. trachomatis. The ribosomal protein L4 and 23S rRNA genes of the susceptible and resistant strains of C. trachomatis were partially sequenced. A double mutation was found in ribosomal protein L4 of the mutants, leading to Pro109(CCG)→Leu(CTG), and Pro151(CCG)→Ala(GCC) (Escherichia coli numbering) in the corresponding protein, but these mutations were also found in parent strains. An investigation into the sequences of 23S rRNAs in the mutants revealed point mutations of A2057G, A2059G and T2611C (E. coli numbering). These results suggest that point mutations located in 23S rRNA were associated with macrolide resistance in C. trachomatis.     

Nonchlamydial nongonococcal urethritis in men

By definition, nongonococcal urethritis (NGU) is an infectious condition involving urethra inflammation without Neisseria gonorrhoeae infection. According to recent studies, NGU accounts for 10–30% of initial visits to sexually transmitted infection (STI) clinics, and is one of the most common forms of STI in men. Chlamydia trachomatis is the most prevalent and well-established pathogen in NGU. However, nonchlamydial NGU is still a problematic disease in clinics because of its minimally symptomatic or asymptomatic manifestation. Various infection causes, including Mycoplasma, Trichomonas vaginalis, and herpes simplex virus, are possible pathogens in nonchlamydial NGU. In this brief review, we focus on the evaluation and management of nonchlamydial NGU.     

武汉地区非淋菌性尿道炎患者泌尿生殖道支原体感染及药敏分析

目的：调查武汉地区非淋菌性尿道炎（NGU）患者泌尿生殖道支原体感染及耐药情况,为临床选择治疗支原体感染的抗生素提供参考依据。方法：采用支原体分离、鉴定、计数、药敏试剂盒检测拟诊为NGU患者的解脲脲原体（UU）和人型支原体（MH）,并分析药敏试验结果。结果：630例患者中支原体总阳性率38．6％,以UU（30％）感染为主,男性感染率明显高于女性。药敏试验结果显示,UU、MH和UU＋MH对药物的敏感性最高者依次为阿奇霉素和美满霉素,uu对氧氟沙星、司帕沙星和罗红霉素耐药性高,MH及uu＋MH则对罗红霉素、红霉素和克拉霉素耐药性高。结论：uu成为本地区NGU的主要病原体,治疗本地区泌尿生殖道支原体感染可首选阿奇霉素和美满霉素。     

Case-control study of men with suspected chronic idiopathic prostatitis

We studied prospectively 50 asymptomatic men (24 men from infertile couples and 26 normal volunteers) with no history of genitourinary infection and 34 men referred for symptoms of chronic prostatitis. Both groups were evaluated by urethral and prostatic secretion cultures for Chlamydia trachomatis, 4-glass prostatic localization cultures for facultative aerobic bacteria (Ureaplasma urealyticum, Mycoplasma hominis and selected fungi) and counts of prostatic fluid leukocytes. The men with symptoms of prostatitis had more than 1,000 leukocytes per mm. in prostatic secretions more often than did controls (11 of 27 versus 0 of 44, p less than 0.001). The concentration of Ureaplasma urealyticum in prostatic secretions was 1 log higher in prostatic fluid localization cultures than in first voided urine in 0 of 30 patients versus 13 of 50 controls (p equals 0.0014). Chlamydia trachomatis was not isolated from any patient or control. No other significant differences were found between patients and controls. We did not identify an infectious cause of chronic nonbacterial prostatitis.     

Genital chlamydial infection in Taiwan

Chlamydial infection is the most common sexually transmitted infection (STI), and is caused by the bacterium Chlamydia trachomatis; however, its overall prevalence rate is not available because it is not a notifiable disease, i.e., it is not reported by government authorities. Therefore, based on the reports of the limited studies available, the prevalence rate of chlamydial infection among patients visiting STI and genitourinary clinics was found to be approximately 16–18%. The risk factors for chlamydial infection are younger age (age ≤30 years), inconsistent condom use, being symptomatic (dysuria or urethral discharge) at the time of testing, and having Neisseria gonorrhoeae infection. In Taiwan, the most commonly reported strain of Chlamydia is genotype E, which is followed by genotypes D and Da, F, K, J, G, and H. C. trachomatis infection is detected using nucleic acid amplification test (NAAT), cell culture, direct immunofluorescence, enzyme immunoassay, and nucleic acid hybridization test. Among these tests, NAAT is the most sensitive Food and Drug Administration-approved urine test for diagnosing the C. trachomatis infection. The primary treatment for chlamydial infection includes either the administration of azithromycin (single dose of 1 g orally) or doxycycline (100 mg twice daily for 7 days); both being equally effective. Chlamydia-infected women and men should be retested approximately 3 months after the initial treatment. For pregnant women, however, the test should be repeated 3 weeks after the completion of therapy to ensure therapeutic cure.     

Semen inflammatory markers and Chlamydia trachomatis infection in male partners of infertile couples

Previous studies have given conflicting results about the effect of generally infection and Chlamydia trachomatis on seminal ILs and semen parameters. The aim of this study was to investigate the relationship between semen quality and the level of seminal interleukins (ILs) in infertile couples with C. trachomatis. Blood, first void urine (FVU) and semen were obtained from 250 infertile men who had failed to conceive after 12 months of trying. Serological analysis for specific IgA, IgM and IgG antibodies to C. trachomatis in serum, the presence of C. trachomatis in FVU and semen sample and semen analysis were carried out. The main results are as follows: (i) elevated IL‐6 and IL‐8 are observed in C. trachomatis‐positive men, but this is not significant and it varies by diagnostic method; and (ii) IL‐6 and IL‐8 levels were correlated with each other and the concentration of leucocytes, but IL‐8 was correlated with semen volume and patient's age. This study showed that men with such an infection in FVU samples (PCR positive) had only lower semen volume compared with men without infection.     

非淋菌性尿道炎实验诊断研究进展

非淋菌性尿道炎 (NGU)是常见的性传播疾病之一。沙眼衣原体是NGU最常见的病原体 ,NGU的病原体还包括溶脲脲原体、生殖支原体、阴道毛滴虫等。随着分子生物学、免疫学的发展 ,PCR、连接酶链反应 (LCR)等新技术被广泛用于实验室诊断研究中 ,因而有必要建立NGU快速、准确的实验诊断方法并将其标准化。本文就NGU的概念、病因学、临床表现、实验室诊断及治疗方面的研究进展作一概述     

Etiology, manifestations and therapy of acute epididymitis: prospective study of 50 cases.

There were 50 patients with acute epididymitis who were evaluated prospectively by history, examination and microbiologic studies, including cultures for aerobes, anaerobes, Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma urealyticum. Escherichia coli was the predominant pathogen isolated from the urine of men more than 35 years old, while Chlamydia trachomatis and Neisseria gonorrhoeae were the predominant pathogens isolated from the urethra of men less than 35 years old. The etiologic role of Escherichia coli and Chlamydia trachomatis was confirmed by isolation from epididymal aspirates from a high proportion of men with positive urine or urethral cultures for these agents. Chlamydia trachomatis epididymitis accounted for two-thirds of idiopathic epididymitis in young men and often was associated with oligospermia. Of 9 female sexual partners of men with Chlamydia trachomatis infection 6 had antibody to Chlamydia trachomatis, of whom 2 had positive cervical cultures for this organism and 2 others had non-gonococcal pelvic inflammatory disease. Antibiotic therapy with tetracycline was effective for the treatment of men with Chlamydia trachomatis epididymitis and should be offered to the female sex partners.     

Effects of Chlamydia trachomatis infection on sperm chromatin condensation and DNA integrity

The present study was performed to investigate the relation of Chlamydia trachomatis infection to sperm chromatin/DNA integrity in a population of infertile men (male partner of infertile couples) from Iran. Blood, semen and first‐void urine samples were obtained from 250 infertile men. Data were analysed with regard to the results of (i) serological analysis for specific antibodies to C. trachomatis in serum; (ii) the presence of C. trachomatis and DNA in first‐void urine; and (iii) in the semen sample of the male partner, in addition to sperm analysis, four different tests (aniline blue, chromomycin A3, acridine orange and TUNEL) were used to detect sperm chromatin and DNA abnormalities. The main conclusions of the results were: (i) no evidence of C. trachomatis infection in semen samples was found; (ii) sperm DNA fragmentation and chromatin studies were not correlated with C. trachomatis diagnosis; (iii) the percentage of DNA fragmentation is positively correlated with the percentage of immotile sperm but negatively with semen volume, normal morphology; and (iv) in sperm chromatin evaluations, only the percentage of chromatin protamination was related to male age.     

泌尿生殖道炎症病人支原体感染现况及耐药性分析

目的 :了解泌尿生殖道炎症病人支原体感染现况及耐药性情况。　方法 :统计 1999～ 2 0 0 3年门诊诊断为非淋菌性尿道炎 (NGU)、慢性前列腺炎及盆腔炎等泌尿生殖道疾病病人 30 5 5例 ,分析其支原体培养及药物敏感试验结果。　结果 :30 5 5例病人共检出支原体感染 992例 ( 32 .5 % ) ,5年间差异无显著性 (P <0 .0 5 )。其中单纯溶脲脲原体 (Uu)感染 70 1例 ( 70 .7% ) ,单纯人型支原体 (Mh)感染 4 4例 ( 4 .4 % ) ,Uu和Mh混合感染 2 4 7例 ( 2 4 .9% ) ,单纯Uu感染远高于混合感染和单纯Mh感染 (P <0 .0 1)。单纯Uu感染计数≥ 10 4cfu/ml占 76 .7% ,而单纯Mh感染者≥10 4cfu仅占 18.2 %。对强力霉素、原始霉素、交沙霉素和四环素敏感性较高 ,分别为 94 .3%、96 .6 %、86 .5 %和97.4 % ,对红霉素和氧氟沙星敏感性仅 5 4 .8%和 2 9.4 %。　结论 :在对病人进行支原体检测时 ,应同时进行Uu和Mh的检测 ,并做支原体药物敏感试验 ,以合理选择抗生素。     

Molecular detection of Chlamydia trachomatis and semen quality of sexual partners of infertile women

Chlamydia trachomatis is considered as the bacterium that is more sexually transmitted as cause of male urethritis, epididymitis, orchitis and infertility. A total of 116 semen samples of men whose couples are infertile women were analysed. The quality of the semen was measured by standard procedures recommended by WHO while C. trachomatis was detected by the PCR assay. Thirty‐seven semen samples were positive for C. trachomatis (31.9%). Regarding semen analysis, no different values were observed between positive and negative samples to C. trachomatis. However, the presence of leucocytes and erythrocytes suggests an inflammatory process; however, these were high in negative samples to C. trachomatis. Furthermore, an association between low seminal volume at 1, 5 ml and the positivity to C. trachomatis was observed (OR=2, 1; CI₉₅% 1,16‐3,07). The total semen volume is a contribution by the various accessory glands (this reflects the secretory activity of the glands); a low semen volume could be due to an obstruction of the ejaculatory duct or infection of accessory glands by C. trachomatis. More studies are necessary to identify the causes of a reduced semen volume.     

May Chlamydia trachomatis be an aetiological agent of chronic prostatic infection?

Chlamydia trachomatis infection is the most common sexually transmitted bacterial disease. The objective of this study was to establish the presence/absence of C. trachomatis in 98 patients with chronic complaints about the prostate and to evaluate the role of this bacterium in the inflammation of the gland. We performed culture and microscopical examination of pre‐massage/post‐massage urine and expressed prostatic secretions (EPS). In all cases, culture on McCoy cells and polymerase chain reaction (PCR) of the EPS was performed. Based on laboratory findings in 53 cases (54.08%), Escherichia coli, Klebsiella, Enterobacter, Proteus, Pseudomonas and Staphylococcus were isolated and accepted as causative agents of chronic bacterial prostatitis. Forty‐five patients were categorised as patients with chronic pelvic pain syndrome. The results from the PCR and the cell culture for detection of C. trachomatis were as follows – two positive probes detected at the same time by applying PCR and cultivation and 1 positive only by PCR but not by cultivation on the cell line. Based on these results, it is concluded that C. trachomatis is not so frequently detected in our patients. C. trachomatis may be accepted as one of the aetiological agents of chronic prostatitis and testing for this infection is highly recommended when presumption for chronic prostatitis is apparent.     

Association of asymptomatic Chlamydia trachomatis infection with male infertility and the effect of antibiotic therapy in improvement of semen quality in infected infertile men

The role of asymptomatic infections caused by Chlamydia trachomatis in male infertility and the efficacy of antibiotics in the treatment of this condition are not yet definitely determined. A total of 165 infertile males having abnormal semen parameters (study group) as well as 165 healthy fertile men (control group) were included. Semen samples were taken from all participants and after analysing for semen parameters, undergone real‐time PCR, and reactive oxygen species (ROS) as well as total antioxidant capacity (TAC) assays. Infected individuals of study group were treated with antibiotic. One month after the treatment completion, second semen samples were taken and undergone all the tests mentioned. The frequency of C. trachomatis was significantly higher in the infertile men compared with the fertile ones (4.2% vs 0.6%). Most of the semen parameters were improved and reached their normal range, the level of TAC elevated and ROS level as well as ROS/TAC ratio reduced after antibiotic treatment. Moreover, wives of three infected infertile men (42.9%) became pregnant 4 months after the treatment completion. Our data suggest that asymptomatic infection caused by C. trachomatis is correlated with male infertility and antibiotic therapy can improve the semen quality and fairly treat the male infertility.