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PubMed2001

Quantitative detection of Chlamydia spp. by fluorescent PCR in the LightCycler.

Quantitative detection of intracellular bacteria of the genus Chlamydia by the standard cell culture method is cumbersome and operator dependent. As an alternative, we adapted hot-start PCR to the glass capillary quantitative PCR format of the LightCycler. The optimized PCR was consistently more efficient than commercially available pre-assembled PCRs. Detection by quantitative PCR of as few as single copies of DNA of Chlamydia spp. was accomplished by SYBR Green fluorescence of the dsDNA product and by fluorescence resonance energy transfer (FRET) hybridization probes. The PCRs were 15-fold more sensitive than the cell culture quantitative assay of C. psittaci B577 infectious stock. The number of chlamydial genomes detected by C. psittaci B577 FRET PCR correlated well with cell culture determination of inclusion forming units (IFUs) (r = 0.96, P < 0.0008). When infected tissue samples were analyzed by cell culture and PCR, the correlation coefficient between IFUs and chlamydial genomes was higher with C. psittaci B577 FRET PCR (r = 0.90, P < 0.0004) than with Chlamydia omp1 SYBR Green PCR (r = 0.85, P < 0.002).

Bacterial Outer Membrane Proteins↗

PubMed2004

[Severe chlamydia pneumoniae pneumonia requiring mechanical ventilation and steroid therapy in an elderly patient].

A 75-year-old man first developed dyspnea and low-grade fever in late March. A chest X-ray film showed infiltration in the right lower lung field and blood gas analysis revealed severe hypoxemia. Accordingly, he was diagnosed as having pneumonia and was admitted to our hospital on March 11, 2003. Mechanical ventilation for progressive respiratory failure was started immediately after admission, and he was treated with antibiotics. Chlamydia pneumoniae pneumonia was diagnosed due to an increase of the Chlamydia pneumoniae antibody titer. He had prolonged respiratory failure despite antibiotic therapy. Therefore, steroid therapy was started on day 15 for respiratory failure. At 21 days after admission, the infiltration was found to be decreased on chest X-ray films and improvement of hypoxemia allowed extubation. In conclusion, when severe community-acquired pneumonia occurs in elderly patients, we should remember the possibility of atypical pneumonia such as that due to Chlamydia pneumoniae infection.

Aged↗

PubMed2003

Gonorrhoea, chlamydia and syphilis incidence in the Kimberley.

The Kimberley region in far-north Western Australia has some of the highest reported incidences of sexually transmitted infections (STIs) in the nation. This report documents the region's incidence rates of gonorrhoea and syphilis from 1997 to 2001 and of chlamydia from 1993 to 2001. Chlamydia rates have been increasing since 1993 when genital chlamydia became a notifiable disease. By contrast, gonorrhoea rates remained stable from 1997 to 2001. Syphilis rates, which plateaued between 1996 and 2000 following a steep decrease in the previous decade, rose in 2001 in association with a regional syphilis outbreak. Factors important in interpreting changes in STI rates over time include the increased accuracy of more recent census data, the introduction of new and more sensitive diagnostic techniques and the influence of health workforce numbers and skills on STI diagnosis.

Chlamydia Infections↗

PubMed1998

Co-cultivation of conjunctival epithelial cells and Chlamydia trachomatis: electron microscopic findings.

This study used primary culture of rabbit conjunctival epithelial cells to investigate the infection process of chlamydia. The epithelial cells isolated from conjunctiva of rabbit were initially cultured for three weeks. After attaining confluence they were infected with Chlamydia trachomatis (C. trachomatis) serotype D, and after co-cultivation for 24, 48, and 96 hours, electron microscopic study was performed. An inclusion body, a characteristic finding of chlamydial infection, was observed in the vicinity of the nucleus after 24 hours of co-cultivation. It contained a large number of elementary and reticulate bodies and their intermediate forms. Infectious particles known as elementary bodies were noted in the inclusion as 20 to 30 microns sized round bodies with an electron dense core. Reticulate bodies were also noted; they too were round but somewhat pleomorphic and larger than elementary bodies. Some reticulate bodies multiplied actively by means of binary fission. In this study, we observed the characteristic changes of C. trachomatis-infected cells; this in-vitro system might provide a suitable model for the study of some aspects of the pathogenesis of ocular chlamydia infection.

Animals↗

PubMed2001

Evaluation of serotyping using monoclonal antibodies and PCR-RFLP for Chlamydia trachomatis serotype identification.

We compared genotyping by restriction fragment length polymorphism (RFLP) analysis of the amplified omp1 gene with serotyping by dot enzyme-linked immunosorbent assay (dot-ELISA) to determine the suitability of RFLP analysis for epidemiologic study. Fifteen prototypes of Chlamydia trachomatis and 30 clinical isolates were used in this study. To serotype with dot-ELISA, chlamydia antigen was spotted onto a series of replicate nitrocellulose membrane patches and reacted with 11 mAbs that distinguish the 15 known serovars of C. trachomatis. For RFLP analysis, the amplified chlamydia omp1 gene was digested with AluI to differentiate serovars A to K and L1 to L3. Serovars of C, H, I, J, and L3 were further typed by RFLP analysis after digestion with HinfI, and a combination of EcoRI and DdeI. PCR-based RFLP could identify serotype of 28 among 30 clinical isolates tested. The remaining two untypical isolates were probably due to double infections or mechanical transferring error. Serotyping of C. trachomatis isolates shows that serovars E, D, F, and H are the most prevalent types found in urogenital samples in Korea. In this study, we show that RFLP analysis of amplified omp1 gene may be useful in genotyping C. trachomatis isolates.

Animals↗

PubMed2005

NF-kappa B activation is not required for Chlamydia trachomatis inhibition of host epithelial cell apoptosis.

Chlamydia trachomatis, an obligate intracellular bacterial species, is known to inhibit host cell apoptosis. However, the chlamydial antiapoptotic mechanism is still not clear. Because NF-kappaB activation is antiapoptotic, we tested the potential role of NF-kappaB activation in chlamydial antiapoptotic activity in the current study. First, no obvious NF-kappaB activation was detected in the chlamydia-infected cells when these cells were resistant to apoptosis induced via either the intrinsic or extrinsic apoptosis pathways. Second, inhibition of NF-kappaB activation with pharmacologic reagents failed to block the chlamydial antiapoptotic activity. Finally, NF-kappaB p65 gene deletion did not prevent chlamydia from inhibiting host cell apoptosis. These observations together have demonstrated that NF-kappaB activation is not required for the chlamydial antiapoptotic activity.

Apoptosis↗

PubMed1988

Evaluation of an enzyme immunoassay test for the diagnosis of Chlamydia psittaci infection in free-ranging koalas (Phascolarctos cinereus) in southeastern Queensland, Australia.

The IDEIA Chlamydia Test, a commercially available antigen-capture enzyme-linked immunosorbent assay (ELISA) test, based on a monoclonal antibody for the detection of chlamydia in clinical specimens, was evaluated in a population of 65 free-ranging koalas in southeastern Queensland determined to be infected with Chlamydia psittaci. Compared to isolation of the organism in tissue culture, the sensitivity of the IDEIA test ranged from 3 to 11%, and the specificity from 90 to 97%. The results indicated that the IDEIA test is unsuitable for use as a diagnostic screening test for C. psittaci in free-ranging koalas.

Animals↗

PubMedDate not supplied

Isolation of Chlamydia psittaci involved in abortion of goats in Mexico: first report.

A group of 35 healthy adult goats ranging from two to six years old were bought from a chlamydiosis and brucellosis-free flock; they were vaccinated against Brucella melitensis with Rev1 vaccine at reduced doses, and one month later placed in isolation units. The animals were one month pregnant at the moment of purchase, and during the third month of pregnancy 10 out of the 35 dams aborted. Necropsy of the aborted fetus and examination of the foetal membranes was performed where no macroscopic lesions were observed. Abomasal liquid, foetal lung and liver, and placenta samples were taken for bacteriological analysis while sera from the goats that aborted was collected for serological investigation. Chlamydia psittaci was isolated in all cases, while no Brucella was detected. All sera reacted positive to anti-Chlamydia antibodies by the indirect immunofluorescence test. This represents the first report of Chlamydia psittaci isolation from cases of goat abortion in Mexico.

Abortion, Veterinary↗

PubMedDate not supplied

[Inborn deficiency of complement C4A and C4B isotypes in persons infected with Chlamydia].

The difference in the functional activity of the isotypes A and B of component C4 of human complement was used to determine their ratio to detect the inherited deficiency of the isotypes. The frequency of deficiency in healthy persons blood donors was equal for C4A and C4B (0.14 for each isotype), i.e. 14% of total number (22) donors, or 28% totally. These results agree with the literary data, on which the frequency of deficiency of C4A is 0.14, and of C4B is 0.11-0.16. The inherent deficiencies of C4A and C4B for persons infected by Chlamydia were studied. For this purpose the patients (35 persons) with in blood antibodies (IgG or IgM) to Chlamydia (C. trachomatis, C. psittaci and C. pneumoniae) were investigated. The frequencies of deficiency of C4A and C4B were 0.29 and 0.46 respectively. Thus, the number of the undeficiency patients was only 25%, while among healthy persons 70-75% of individuals not having deficiencies of isotypes C4 were observed. The deficiencies of isotypes of C4 at this pathology is detected for the first time. The obtained data suggest the existence of the predisposition to the development of diseases stipulated by Chlamydia in persons with inherent deficiency of C4 component of complement.

Adult↗

PubMed2001

[Follicular conjunctivitis due to Chlamydia trachomatis].

During two years (1997-1999) an investigation of possible infections of chlamydial etiology in outpatients with follicular conjunctivitis was carried out, through the use of specific assays. Fifty-seven selected patients with presumptive inclusion conjunctivitis were diagnosed by means of ophthalmoscopic examination and bilateral tarsal-conjunctiva swabbing for microorganisms. The possible presence of Chlamydia trachomatis was tested by immunofluorescence microscopy and isolation in cell culture of McCoy line. Of the 57 conjunctivitis patients screened, 37 (65%) proved to be positive by cell culture (CC) and 27 (47%) by direct immunofluorescence (IFD). A good agreement between the two assays was observed, where the CC was more sensitive than IFD. Of these 37 patients with chlamydial conjunctivitis, 23 (62%) were women, with over one-third of them ranging in age from 45 to 65 years. Their clinical records revealed an evolution period of 1 to 12 months. Eighteen (78%) of these women reported previous genital pathology, while 4 (29%) of the 14 men had a history of urethritis by Chlamydia trachomatis. A high frequency of follicular conjunctivitis by Chlamydia (65%) in the screened patients was observed, without any evidence of urogenital signs and symptoms at the moment of the study.

Adolescent↗

PubMed1999

Etiology of trachoma: a great success in isolating and cultivating Chlamydia trachomatis.

PURPOSE: To review the studies on the etiology of trachoma and to honor Professor Tang Feifan (Prof. FF Tang). He is the first scientist who was successful in isolating and cultivating chlamydia trachomatis in 1946. DATA SOURCES: The principal literatures are cited from Tang's papers published from the 1930s to the 1950s. Earlier literatures concerning early hypotheses for trachoma pathogenic agent are also studied. STUDY SELECTION AND DATA EXTRACTION: Only important and conclusive breakthroughs in Tang's papers are selected and extracted. RESULTS AND CONCLUSIONS: In the 1930s Tang was intending to repeat Noguchi's experiments in isolating bacterium granulosis from cases of trachoma in China and to employ bacterium granulosis isolated by Noguchi in 1928 for reproducing experimental trachomatous human clinical manifestations in China. Both experiments showed negative results. In the 1950s, before isolated chlamydia trachomtas, Tang and his colleagues had finished two fundamental studies: (1) the histological nature of trachoma, their relationship to etiological agent as well as to the host cells; and (2) the clinical manifestations and the morphological pictures of trachoma in monkeys. Eventually chlamydia trachomatis was isolated successfully and cultivated continuously.

Bacteriology↗

PubMed2002

Comparison of two microimmunofluorescence tests for detecting antibodies to Chlamydia pneumoniae.

Two microimmunofluorescence (MIF) tests were compared for detection of antibodies to Chlamydia pneumoniae: the microimmunofluorescence of Washington University and the microimmunofluorescence of Chlamydia Serofia. Concordant positive results at the same dilution were observed for IgG in 37.33% of sera tested and concordant negative results were found in 44%. Variations of one fold dilution were observed in 36 sera. Extensive variations (2-3 two-fold dilutions) in the numeric titer values were observed in 20 serum samples with titers of antibody generally higher in the Chlamydia Serofia MIF than in the Washington MIF, resulting in a diagnosis of current infection in three patients. IgM were found with both methods only in one patient. The discrepancies observed may be due to several factors including the different TWAR strain used as antigen in the two tests and the dilution of the FITC-labelled conjugated anti-human IgG. We think that MIF serology may also be influenced by the type of response of the host that may depend on the "local strain" of C. pneumoniae that may express different antigens or in different amounts in comparison with the strains used by the commercial kit.

Antibodies, Bacterial↗

PubMedDate not supplied

Cutaneous vasculitis and reactive arthritis following respiratory infection due to Chlamydia pneumoniae: report of a case.

Unlike Chlamydia trachomatis and C. psittaci, the association of C. pneumoniae infection with immunological complications, such as reactive arthritis (ReA) or erythema nodosum (EN) has been rarely reported. Here we present the case history of a patient with C. pneumoniae community acquired pneumonia (CAP) who subsequently developed a ReA and a cutaneous vasculitis. A 45-year-old HLA B27 negative male developed an asymmetric and additive arthritis and a cutaneous leukocytoclastic vasculitis with IgM and complement papillary deposition along hypodermic vessel walls about three weeks after the onset of respiratory symptoms. The diagnosis of chronic Chlamydia pneumoniae infection was based on serology and PCR. Cultural and serological investigations for other infectious agents commonly involved in ReA were negative. This is the first report on the occurrence of two immune-based complications, associated to Chlamydia pneumoniae infection. Therefore, since this infection is very common in our population, although often asymptomatic, should be systematically considered as a common causative agent of ReA and of vasculitis.

Arthritis, Reactive↗

PubMed2000

[Evaluation of polymerase chain reaction for detection of chlamydia trachomatis in eye swabs].

OBJECTIVE: To investigate the clinical value of Polymerase Chain Reaction (PCR) in the diagnosis of trachoma. METHODS: Direct amplication of 16S rRNA gene which is chlamydia-specific by PCR was used to detect chlamydia trachomatis (CT). RESULTS: Of 93 subjects who conformed to the diagnosis criteria of trachoma, 69 (74.2%) was PCR-Positive; Of 178 subjects who did not comform to the criteia, 6(3.4%) was PCR-positive. PCR had a sensitivity of 74.2% and a speciticity of 96.7% for the clinical diagnosis of trachoma. The difference between trachoma group and nontrachoma group is significant(P < 0.001). CONCLUSION: The PCR may be a good method in the diagnosis of ocular chlamydia trachomatis infection because of its excellent sensitivity and specificity.

Adolescent↗

PubMed2003

Chlamydia trachomatis infections among Yemeni school pupils in relation to environmental conditions.

OBJECTIVE: This study is aimed at establishing the prevalence of Chlamydia trachomatis infections among school pupils in Sana'a, Republic of Yemen, and to explore the association of infection with environmental and social factors. METHODS: A total of 787 school children, 529 boys and 258 girls, were randomly selected for enrollment in this study. Four hundred and twenty-nine were from 4 schools in Sana'a city, and 358 from 3 rural schools around Sana'a, Republic of Yemen. Questionnaire forms were filled in for each child to investigate environmental and social factors. Sera were tested for anti Chlamydia trachomatis IgG antibodies using enzyme-linked immunosorbent assay CTM-IgG . RESULTS: An overall rate of infection of 45.9% was determined. The rate of infection among rural pupils (73.2%) was higher (P<0.0001) than that among urbanones (23.1%). The rate of infection was found significantly (P<0.001) inversely correlated with age of the pupils. Environmental factors which were found to influence the infection rate were; rural residence, unplastered walls, mud floor, lack of stand pipe water, lack of latrine and presence of animals within dwelling with odds ratio of 9.1, 6.3, 6.1, 5.2, 3.7, 3.5 and 1.7. Also, the male sex and illiteracy of the parents has been found to be risk factors for infection. CONCLUSION: Prevalence of Chlamydia trachomatis infection was found to be high. The prevalence correlates inversely with age. Rural residence, environmental conditions and social factors were risk factors for infections. Yemen could be identified as a trachoma endemic area, which should be targeted by the control programs.

Adolescent↗

PubMed2003

[Chlamydia pneumoniae as a biological factor contributing to pathological changes of arterial walls in patients with atherosclerosis].

In this study, using scanning and transmission electron microscope, we attempt to evaluate ultrastructural alterations of endothelial cells, macrophages and smooth muscles cells. The inflammatory process has an essential impact on the development of Chlamydia infection. Specimens from human carotid were obtained from patients who underwent endarterectomy. For examination under scanning and transmission electron microscope vessel sections were fixed in paraformaldehyde and glutaraldehyde. We analysed alterations of endothelial cells covering advanced atherosclerotic plaque in carotid using scanning electron microscope. Smooth muscle cells had undergone the heaviest proliferation among the cells on artery wall. In the tested material we detect diversified morphological forms of Chlamydia sp. We found that one of the pathogens that may lead to atherosclerotic lesions is Chlamydia pneumoniae.

Aged↗

PubMed1992

A novel 3-deoxy-D-manno-octulosonic acid transferase from Chlamydia trachomatis required for expression of the genus-specific epitope.

DNA cloned from Chlamydia trachomatis is able to direct the formation of the genus-specific lipopolysaccharide epitope of chlamydiae in enteric Gram-negative bacteria. We now demonstrate that a single C. trachomatis gene (gseA) is sufficient to impart this trait to Escherichia coli. The deduced amino acid sequence of gseA shows 23% identity (66% similarity) to kdtA, an E. coli gene that codes for a bifunctional enzyme catalyzing the addition of two 3-deoxy-D-manno-octulosonic acid (Kdo) residues to lipid A precursors (Clementz, T., and Raetz, C. R. H. (1991) J. Biol. Chem. 266, 9687-9696). Extracts of E. coli expressing gseA transfer at least one additional Kdo unit from CMP-Kdo to precursors already bearing the two Kdo residues attached by the kdtA gene product. Introduction of gseA into an E. coli mutant with a thermolabile kdtA gene product endows cell extracts with the ability to transfer not only the third but also the first two Kdos to lipid A precursors, demonstrating that the C. trachomatis enzyme is at least trifunctional. Given the similarities of these two Kdo transferases and the essentiality of Kdo in Gram-negative bacteria, lipopolysaccharide biosynthesis may be a target for development of novel drugs effective against chlamydiae.

Amino Acid Sequence↗

PubMed2003

Lymphocytes and their subpopulations in peripheral blood of rabbits immunised with Chlamydia psittaci-Gocaltovo strain.

The effects of immunisation with Chlamydia psittaci-Gocaltovo strain were examined on the dynamic alterations in lymphocytes T and B and in their subpopulations in the peripheral blood of rabbits; the titer of specific anti-Chlamydia antibodies was also established. The results showed that the examined strain induced alterations in the form of an increased or decreased number of T and/or B lymphocytes and in their subpopulations, and that immunity conditioned by the cells proved to be a very significant variable in infection with Chlamydia psittaci (at present Chlamydophila abortus). Alterations in the immune pattern developed earlier by 35 days as compared to positive titers of specific antibodies.

Animals↗