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PubMed1991

Sequence diversity of the 60-kilodalton protein and of a putative 15-kilodalton protein between the trachoma and lymphogranuloma venereum biovars of Chlamydia trachomatis.

DNA from Chlamydia trachomatis serovars L3, C, and E corresponding to the open reading frames of the 60-kDa protein and of a putative 15-kDa protein was sequenced. The open reading frames coding for the 60-kDa protein had 1,641 bp in the three serovars. Compared with the L3 serovar, there were 9 and 11 amino acid changes in the C and E serovars, respectively. The open reading frames corresponding to the putative 15-kDa protein had 450, 456, and 453 bp for the L3, C, and E serovars, respectively. When compared with the L3 serovar, the C and E serovars had 14 and 16 amino acid differences, respectively.

Amino Acid Sequence↗

PubMed1997

Antigen conformation dependence of Chlamydia trachomatis infectivity neutralization.

Chlamydia trachomatis infections cause the most common notifiable diseases in the United States, reflecting the successful adaptation of these organisms to persist in their obligate human host population. Antigenic variation of the quantitatively predominant major outer membrane protein (MOMP) is considered to play an important role in this adaptation as a means of immune evasion. The relative capacity of murine polyvalent sera produced following infection, recovery, and challenge to neutralize infectivity was highly serovar-specific and dependent upon thermolabile antigens. The structural complexity of these immunodominant antigens was mimicked by chlamydial MOMP expressed in Escherichia coli, as antibodies that neutralize infectivity by recognition of conformation-dependent antigens were specifically removed from sera following absorption using MOMP expressed in E. coli.

Animals↗

PubMed2000

Reversal of intra-amniotic Chlamydia trachomatis antigen status.

Chlamydia trachomatis (CT) infection in pregnant women is related to unfavorable obstetric outcomes such as prematurity, intrauterine growth retardation, and stillbirth. A 22-year-old woman underwent transabdominal amniocentesis at 16 weeks of gestation (GW). A CT antigen test using polymerase chain reaction in the amniotic fluid was found to be positive, though the patient had no symptom of infection. Beginning at 20 GW, clarithromycin was orally administered at a dose of 400 mg/day for 2 weeks. The CT antigen test in amniotic fluid at 28 GW turned to a negative result. A female baby was vaginally born at 38 GW by spontaneous labor. The CT antigen test of her gastric contents showed a negative result and anti-CT IgM in umbilical cord blood was negative. Neither respiratory distress, pneumonia, nor conjunctivitis was detected. To the best of our knowledge, this case is the first report showing the reversal of the intra-amniotic CT antigen status by antibiotic treatment.

Adult↗

PubMed1994

Determination of neutralizing epitopes in variable domains I and IV of the major outer-membrane protein from Chlamydia trachomatis serovar K.

Chlamydia trachomatis is a leading cause of sexually transmitted diseases and a number of strategies have been developed to produce vaccines to prevent its transmission. The purpose of this study was to map the neutralizing epitopes of C. trachomatis major outer-membrane protein (MOMP) serovar K by using anti-MOMP antibodies and synthetic peptides. Seven anti-MOMP monoclonal antibodies and three polyclonal antisera were produced and characterized. Their fine specificity was defined by direct binding assay on 15 peptides of 10 amino acid residues, overlapping by five residues, corresponding to the four variable domains (VDI-VDIV: residues 64-85, 139-160, 224-237 and 287-319) of MOMP serovar K. Our data confirmed that a neutralizing epitope is found in VDIV, defined by peptides K12 and K13. This epitope is 296TTLNPTIAG304, which has never been reported as a neutralizing epitope of serovar K. Another neutralizing epitope, defined by peptide K2, has been identified in VDI. This epitope is in the same position as 71VAGLEK76, a peptide with neutralizing activity found in serovar A, but they are not identical because antibodies against peptide K2 do not bind to this epitope. No neutralizing epitope was found in the two other variable domains (VDII and III). In summary, two neutralizing sites, one in variable domain I and one in variable domain IV, were identified in serovar K.

Amino Acid Sequence↗

PubMed1991

Immunoelectron microscopic localization of chlamydial lipopolysaccharide (LPS) in McCoy cells inoculated with Chlamydia trachomatis.

Interactions between Chlamydia trachomatis, host cells, and the immune system are believed to involve lipopolysaccharide (LPS). We used immunogold techniques to study the distribution of chlamydial LPS in cultured cells infected with C. trachomatis LGV-L1. McCoy cells inoculated with C. trachomatis were cultured and then fixed and embedded in situ with acrylic resins. Sections were immunolabeled with a protein A-gold method using antisera to the genus-specific, periodate-sensitive epitope on chlamydial LPS. Pre-embedding immunogold labeling on permeabilized cells was also done. By post-embedding methods, labeling for LPS was equally abundant over the outer membranes of elementary (EB) and reticulate bodies (RB). By post-embedding labeling, the sub-surface side of the EB outer membrane was more heavily labeled than the surface side. By pre-embedding labeling, LPS was found to be less abundant on the surface of EBs than RBs. Labeling for LPS was found over apparent lysosomes in McCoy cells and over electron-dense blebs on or near the surface of the plasma membranes of McCoy cells. These results indicate that the concentration of LPS in chlamydial membranes is constant during development but that with development its location changes from being mostly cell-surface to sub-surface. These results show that the post-embedding immunogold technique can be a useful approach for the cell culture-based study of chlamydial LPS.

Acrylic Resins↗

PubMed2000

Comparison of four nonculture diagnostic tests for Chlamydia trachomatis infection.

OBJECTIVE: Chlamydia trachomatis (CT) is one of the commonest sexually transmitted diseases leading to urethritis, epididymitis, prostatitis in men and urethritis, cervicitis, endometritis and pelvic inflammatory disease, sometimes complicated by infertility and ectopic gestation in women. Since culture of fastidious bacteria in a monocellular medium is not available in most laboratories we compared direct immunofluorescence antigen detecting test (DFA) with three other nonculture tests-antigen detecting enzyme immunoassay (EIA), Papanicolaou staining (Pap) and Geimsa stain for endocervical swabs from women in reproductive age group. METHODS: Three hundred and fifty seven women between 16 and 41 years of age and attending family welfare clinics of IRR were evaluated for the presence pap smears. In 100 cases DFA staining was compared with Geimsa staining. RESULTS: DFA test was positive in 60/357 (16.8%), EIA in 29 (8.1%) of cases and Pap smear in 37 (10%) cases. In the second group DFA was positive in 17 (17%) and Geimsa in 10 (10%) cases. CONCLUSION: Amongst the four tests DFA showed maximum sensitivity. ELISA is less expensive but has lower sensitivity. Pap stain also has less sensitivity and good specificity, the quality of smear is likely to affect the diagnosis. Though Geimsa stain is cheapest, for chlamydial cervicitis in our experience it was not as sensitive as DFA. Thus each laboratory must decide the method depending on its resources.

Adolescent↗

PubMed1993

In vitro transcription in Chlamydia psittaci and Chlamydia trachomatis.

Extracts of Chlamydia psittaci and Chlamydia trachomatis were used to transcribe molecularly cloned chlamydial genes in vitro. The extracts were prepared by lysing reticulate bodies, obtaining the 10,000 x g centrifugation pellet, and eluting RNA polymerase from the pellet by treatment with 2M KCl to yield a fraction designated SS2. Some in vitro transcription was initiated from non-chlamydial promoters and a small amount of transcription was from endogenous DNA template in SS2. However, optimal transcription from exogenous templates required chlamydial promoter sequences, and primer extension analysis indicated that chlamydia promoter-specific in vitro transcription was initiated from the same start sites recognized in vivo. A monoclonal antibody that was generated against Escherichia coli sigma 70 and which immunologically cross-reacts with C. trachomatis sigma 66 inhibited in vitro transcription of vector and cloned chlamydial DNA, suggesting that transcriptional initiation in the SS2 fraction is mediated by sigma 66. An in vitro transcription assay based on detection of transcripts of specific lengths was applied to the chlamydial system; this assay and others described here should be useful in defining chlamydial promoters and other transcriptional regulatory elements.

Base Sequence↗

PubMed2003

The prevalence of Chlamydia trachomatis infection in pregnant Thai women.

Chlamydia trachomatis infection is the most common sexually transmitted infection. It can cause pelvic inflammatory disease and subsequently result in tubal infertility. Chlamydia trachomatis infection in pregnancy can also cause neonatal conjunctivitis and pneumonia. This descriptive study showed that Chlamydia trachomatis infection of the cervix among pregnant women, more than 37 weeks of gestation, attending the prenatal clinic at King Chulalongkorn Memorial hospital was found in 10 per cent by means of multiplex polymerase chain reaction (PCR) technique and 2 per cent by using culture method. The present study demonstrated that all the 182 newborn infants had no neonatal Chlamydia trachomatis infection by using multiplex PCR and culture method. All the babies had Apgar's score of more than 7. At 2 months follow-up, 155 infants were evaluated and had no evidence of Chlamydia trachomatis infection.

Adolescent↗

PubMed1988

Chlamydia trachomatis perihepatitis with ascites.

Chlamydia trachomatis as an etiological agent in the Fitz-Hugh-Curtis syndrome has recently been reported; however, the condition has not been typically associated with ascites. We report a case of Chlamydia trachomatis perihepatitis in a young woman who had exudative ascites as a predominant clinical feature of her disease. Laparoscopy revealed characteristic "violin string" adhesions which were also identified on abdominal computerized tomographic scan.

Adult↗

PubMed1986

Immunocytochemical detection of Chlamydia trachomatis on cytological specimens.

Chlamydia trachomatis can cause many kinds of diseases in humans, both men and women. Its diagnosis depends on the observation of intracytoplasmic inclusion bodies on smears. To observe intracytoplasmic inclusion bodies we applied the Papanicolaou and immunocytochemical techniques. Elementary and reticulate bodies were seen more easily using the immunocytochemical technique in 3 hours on gynecological and urethral specimens. The immunocytochemical technique is rapid, accurate and specific with unstained gynecological and urethral specimens as well as destained Papanicolaou smears. It appears that fixation is the most important factor in immunocytochemical observations of Chlamydia. Absolute methanol or ethanol was the fixation agent of choice based on our experience. After proper fixation, the immunocytochemical technique can be applied for routine examinations to detect Chlamydia trachomatis.

Chlamydia Infections↗

PubMed2002

In vitro activities of BMS-284756 against Chlamydia trachomatis and recent clinical isolates of Chlamydia pneumoniae.

The in vitro activities of BMS-284756 (a novel des-fluoroquinolone), levofloxacin, moxifloxacin, and clarithromycin were tested against 5 strains of Chlamydia trachomatis and 20 isolates of Chlamydia pneumoniae. The MIC at which 90% of the isolates were inhibited and the minimal bactericidal concentration at which 90% of the isolates were killed by BMS-284756 for all isolates of C. pneumoniae and C. trachomatis was 0.015 microg/ml (range, 0.015 to 0.03 microg/ml). BMS-284756 was the most active quinolone tested.

Anti-Infective Agents↗

PubMedDate not supplied

Screening for Chlamydia trachomatis at a university health service.

Chlamydia trachomatis is the most common sexually transmitted infection in the United States. The aim of this study was to determine the prevalence of Chlamydia in college family planning patients and to identify diagnostic indicators associated with Chlamydia. A thorough history and physical examination was performed, including culture for gonorrhea, cancer (papanicolaou test), and Chlamydia trachomatis. Chlamydia occurred in 12.6% of 419 subjects. The lack of signs and symptoms and the possibility of inaccurate historical data limit the clinical predictability of chlamydial infections. Routine screening of college women is recommended.

Adolescent↗

PubMed1990

[Chlamydia trachomatis infection in women with ectopic pregnancy].

Chlamydia trachomatis infection, presumably sexually transmitted, has been implicated in the spread of tubal infertility and ectopic pregnancy. In searching evidence of Chlamydia trachomatis infection as a possible cause of tubal ectopic pregnancy, we enrolled 40 consecutive pathologically proven tubal ectopic women and 37 normal early intrauterine pregnant women from our OPD and ward from Jan. 1989 to July 1989. All cases underwent a structured interview giving particular attention to past reproductive history, contraception history and past history of STD. The levels of serum antibody IgG to Chlamydia trachomatis in all cases were determined. Seven ectopic women with wearing IUD in situ (group A) and 33 ectopic women with no identical factor (group B) were compared with 37 normal early intrauterine pregnant women (control group). The result showed group B more often had IgG antibody to Chlamydia trachomatis than control group (P = 0.001). Group A had higher antibody to Chlamydia trachomatis than control group but the difference was not statistically significant (P greater than 0.05). We concluded that the above findings add to the evidence that Chlamydia trachomatis infection is a major cause of tubal ectopic pregnancy.

Adult↗

PubMed2003

In vitro activities of rifamycin derivatives ABI-1648 (Rifalazil, KRM-1648), ABI-1657, and ABI-1131 against Chlamydia trachomatis and recent clinical isolates of Chlamydia pneumoniae.

ABI-1648 (rifalazil) is a semisynthetic rifamycin with potent bactericidal activity against intracellular respiratory bacteria, including Mycobacterium tuberculosis, and a long half-life (approximately 60 h) and thus can be administered once weekly. We therefore tested the in vitro activities of ABI-1648, its derivatives ABI-1657 and ABI-1131, azithromycin, and levofloxacin against 10 strains of Chlamydia trachomatis and 10 recent clinical isolates of Chlamydia pneumoniae. The MICs at which 90% of the isolates were inhibited and the minimal bactericidal concentration at which 90% of the isolates were killed for ABI-1648, ABI-1657, and ABI-1131 were 0.0025 micro g/ml for C. trachomatis and 0.00125 to 0.0025 micro g/ml for C. pneumoniae. ABI-1648, ABI-1657, and ABI-1131 were 10- to 1,000-fold more active than azithromycin and levofloxacin.

Anti-Bacterial Agents↗

PubMed2000

Interventions for treating genital chlamydia trachomatis infection in pregnancy.

BACKGROUND: Chlamydia trachomatis is a sexually transmitted infection. Mother-to-child transmission can occur at the time of birth and may result in ophthalmia neonatorum or pneumonitis in the newborn. OBJECTIVES: The objective of this review was to assess the effects of antibiotics in the treatment of genital infection with Chlamydia trachomatis during pregnancy with respect to neonatal and maternal morbidity. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register (Cochrane Library issue 1, 1999). SELECTION CRITERIA: Randomised trials of any antibiotic regimen compared with placebo or no treatment or alternative antibiotic regimens in pregnant women with genital Chlamydia trachomatis infection. DATA COLLECTION AND ANALYSIS: Trial quality assessments and data extraction were done independently by two reviewers. Study authors were contacted for additional information. MAIN RESULTS: Eleven trials were included. Trial quality was generally good. Amoxycillin appeared to be as effective as erythromycin in achieving microbiological cure (odds ratio 0.54, 95% confidence interval 0.28 to 1.02). Amoxycillin was better tolerated than erythromycin (odds ratio 0.16, 95% confidence interval 0.09 to 0.30). Clindamycin and azithromycin also appear to be effective, although the numbers of women included in trials are small. REVIEWER'S CONCLUSIONS: Amoxycillin appears to be an acceptable alternative therapy for the treatment of genital chlamydial infections in pregnancy when compared with erythromycin. Clindamycin and azithromycin may be considered if erythromycin and amoxycillin are contra-indicated or not tolerated.

Anti-Bacterial Agents↗

PubMed1983

[Non-gonococcal urethritis and cervicitis. Isolation of Chlamydia trachomatis and detection of anti-Chlamydia antibodies by indirect immunofluorescence].

The responsibility of Chlamydia trachomatis in non-gonococcal urethritis and cervicitis was investigated in 267 patients of both sexes. It was confirmed in 36.3% of patients with urethritis and 20.9% of patients with cervicitis by isolating C. trachomatis on Hela 229 cells in the presence of cytochalasin B. No clinical feature specific of C. trachomatis infection could be elicited. The patients were tested for total IgM-type serum anti-chlamydia antibodies by indirect immunofluorescence (IF), using as antigen the inclusions formed in Hela 229 cells by an L2 serotype of C. trachomatis. The serological study was also performed in 86 blood-donors used as controls. The diagnostic value of IF serology is limited in lower genito-urinary infections; the presence of specific IgM's correlates well with the isolation of C. trachomatis, but these IgM's are not detected in protracted urethritis or cervicitis. In such cases, the aetiological diagnosis can only be made by isolation of C. trachomatis from the focus of infection.

Adolescent↗

PubMed2002

[The infections by Chlamydia trachomatis and Neisseria gonorrhoeae].

Among sexually transmitted diseases, Chlamydia trachomatis and Neisseria gonorrhoeae infections are found most frequently. Recently, their incidence in youths has increased. The rate of infection by human immunodeficiency virus is increased in patients who have been infected by Chlamydia trachomatis. In view of this, early detection and treatment of Chlamydia trachomatis infection appear to be important. Asymptomatic infections by Chlamydia trachomatis and Neisseria gonorrhoeae are not rare among gynecological patients. However, in patients infected by both of these pathogens it is difficult to detect microbial antigens using specific antibodies. Therefore, patients suspected of infection by these pathogens should receive precise genetic testing for Chlamydia trachomatis and Neisseria gonorrhoeae, and the results of such tests should be evaluated carefully.

Chlamydia Infections↗

PubMed2001

Incidence of Chlamydia trachomatis and other potential pathogens in neonatal conjunctivitis.

OBJECTIVE: Ocular infection in neonatology is a permanent and important health problem. To improve primary attention, prevention, and control, the study of the potential bacterial etiology of all consecutive cases of conjunctivitis was incorporated as a regular procedure in primary care from July 1995 to December 1998. MATERIALS AND METHODS: Prof. A. Posadas Hospital (Great Buenos Aires) has an average of 4294 births per year. This report analyzes the results obtained in 332 infants (age range, 0-30 d) with conjunctivitis. Clinical conjunctivitis was diagnosed in inpatients and outpatients by the same specialized staff. Isolation and characterization of bacteria were done by conventional microbiologic methods, including specific search for Neisseria gonorrhoeae and Chlamydia trachomatis. Chlamydia trachomatis was studied by antigen immunodetection and polymerase chain reaction, and genotyped by restriction fragment length polymorphism. RESULTS: Conjunctivitis had an incidence (cases per 1000 live births) of 39.6 in 1995, 25.3 in 1996, 15.4 in 1997, and 15.2 in 1998. Microbial growth was detected in 167 (50.3%) of 332 cases. Ocular C. trachomatis infection was detected in 26 cases (7.83%). Five of seven isolates in tissue cultures belonged to type E and two to type G. Bacteria from respiratory ecology were the main isolates: Haemophilus influenzae (16.9%), Streptococcus pneumoniae (12.3%), and Staphylococcus aureus (8.7%). Haemophilus influenzae isolates were not serotyped and 17.2% of them were b-lactamase producers. In 15 cases both H. influenzae and S. pneumoniae were isolated together. Of S. pneumoniae, 4.9% were oxacillin resistant. CONCLUSIONS: There has been a decline in the total number of cases of neonatal conjunctivitis, but the disease is still an important health problem. Chlamydia trachomatis also shows a decreasing profile with an incidence of (cases per 1000 live births) 4.39 in 1995, 1.85 in 1996, 1.01 in 1997, and 0.78 in 1998, and a tendency to show more incidence in spring-summer and significant accumulation of cases in babies between 7 and 9 days of age. Haemophilus influenzae alone (12.3%) or associated with S. pneumoniae (4.5%) appears as a prevalent potential bacterial pathogen. A significant accumulation of H. influenzae and S. pneumoniae cases occurs in winter. In 47.6% of cases, there was no bacterial growth. No significant seasonal differences in percentage of negative cultures or among the three-day age groups were detected. Neisseria gonorrhoeae was not found associated with ophthalmia neonatorum in this series.

Age Factors↗