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PubMed1995

Chlamydia trachomatis in pelvic inflammatory disease.

The prevalence of genital Chlamydia trachomatis infection and some epidemiologic factors associated with it were studied in 273 pelvic inflammatory disease (PID) patients attending Gynaecologic clinic, Government Medical College, Nagpur. For detection of chlamydial antigen Pharmacia Diagnostics Chlamydia EIA test was used. This study revealed an overall positivity rate of 33% for C. trachomatis infection in PID patients. Of the hypothesised risk factors low socioeconomic status, history of sexual contacts with multiple partners and use of intrauterine devices (IUD) were significantly associated with C. trachomatis infections. However, use of oral contraceptives, barrier contraceptives and increasing age were found to be protective factors for C. trachomatis infection. Thus considering the significant contribution of C. trachomatis in etiology of PID and its independent association with some epidemiologic risk factors, extensive epidemiologic measures are recommended for prevention of these infections.

Adult↗
PubMed2002

Non-LPS components of Chlamydia pneumoniae stimulate cytokine production through Toll-like receptor 2-dependent pathways.

Recent studies suggest that infection with Chlamydia pneumoniae is associated with atherosclerosis, and that cytokines play an important role in the initiation and progression of Chlamydia-induced inflammation. When freshly isolated peripheral blood mononuclear cells (PBMC) were stimulated for 24 h with sonicated C. pneumoniae, significant amounts of the pro-inflammatory cytokines TNF-alpha and IL-1beta and of the anti-inflammatory cytokine IL-10 were released into the supernatant. The addition of serum increased cytokine release induced by C. pneumonia two- to fivefold (p < 0.01). This effect was not due to complement, mannose-binding lectin (MBL) or lipopolysaccharide-binding protein (LBP). Incubation of PBMC with either anti-Toll-like receptor 4 (TLR4) or anti-CD14 blocking antibodies did not influence the production of cytokines induced by Chlamydia. The induction of cytokines by C. pneumoniae in macrophages from C3H / HeJ mice, known to have a defective TLR4, was identical to that measured in control macrophages from C3H / HeN mice. In contrast, incubation of PBMC with an anti-TLR2 blocking antibody significantly inhibited the production of TNF by 67 % and of IL-1beta by 72 %. In conclusion, C. pneumoniae stimulates cytokine production in a serum-dependent manner, but independently of complement, MBL and LBP. C. pneumoniae induces the pro-inflammatory cytokines TNF and IL-1beta through TLR2, but not TLR4 and CD14.

Acute-Phase Proteins↗
PubMed2003

Phylogenetic evidence for two new insect-associated Chlamydia of the family Simkaniaceae.

On the basis of 16S-23S ribosomal DNA analyses, the whitefly Bemisia tabaci (Sternorrhyncha, Aleyrodidae) and the eriococcid Eriococcus spurius (Sternorrhyncha, Eriococcidae) were each found to harbor novel related chlamydial species within the family Simkaniaceae. The generic designation Fritscheagen. nov. is proposed to accommodate the two species, F. bemisiaesp. nov. and F. eriococci sp. nov. The finding of chlamydial 16S-23S ribosomal DNA in B. tabaci is consistent with a previous electron microscopy study which found that bacteriocytes of this species contain structures that we consider to resemble the elementary and reticulate bodies of chlamydia (Costa HS, Westcot DM, Ullman DE, Rosell R, Brown JK, Johnson MW. Protoplasma 189:194-202, 1995). The cloning and sequencing of a 16.6 kilobase DNA fragment from F. bemisiae indicated that it contains six genes encoding for proteins similar to those found in other species of chlamydia. These results extend the range of organisms that harbor chlamydia.

Animals↗
PubMed2003

Role of Chlamydia pneumoniae and Mycoplasma pneumoniae as causative agents of community-acquired pneumonia in hospitalised children and adolescents.

The aim of the study presented here was to determine the prevalence of Chlamydia pneumoniae versus Mycoplasma pneumoniae infections in paediatric patients with community-acquired pneumonia. A total of 50 patients (mean age, 5.5 years; median, 3.9 years) with community-acquired pneumonia were enrolled. Four patients were found to have Chlamydia pneumoniae infection (1 culture positive, 1 PCR positive and 2 serology positive) and 16 patients had Mycoplasma pneumoniae infection (2 PCR positive, 4 PCR and serology positive, 10 serology positive), including three patients with coinfection. The rates of Mycoplasma pneumoniae infection were 22%, 35% and 40% in children aged 1-3, >3-7 and >7 years, respectively. Acute Chlamydia pneumoniae infection was substantially less common than Mycoplasma pneumoniae infection in our study cohort.

Adolescent↗
PubMed2000

The Role of Chlamydia in Upper Respiratory Tract Infections.

Although Chlamydia pneumoniae and Chlamydia psittaci are well-established causes of community-acquired pneumonia, little is known about the role of Chlamydia species in upper respiratory tract infections. C. pneumoniae may play a role in the pathogenesis of acute otitis media. Although C. pneumoniae has been isolated from the middle-ear fluid of children with otitis, children in whom the organism was isolated from middle-ear fluid improved despite being treated with antibiotics that are not active against C. pneumoniae. Although many patients with community-acquired pneumonia caused by C. pneumoniae have symptoms suggestive of sinusitis, there is only one report of isolation of the organism from the maxillary sinus of a patient with sinusitis. Studies of the association with pharyngitis are all based on serology, which often has a poor correlation with isolation of the organism by culture.

Journal Article↗
PubMed2003

Chlamydia pneumoniae carriage and infection in hospitalized children with respiratory tract diseases.

BACKGROUND: The importance of Chlamydia pneumoniae respiratory tract infection in childhood is under discussion. PATIENTS AND METHODS: 798 hospitalized children with respiratory tract diseases were prospectively studied during a 2-year period by polymerase chain reaction and enzyme immunoassay (PCR-EIA) detection from throat swabs. Paired serum samples were used to screen for Chlamydia antibodies. RESULTS: C. pneumoniae was detected by PCR-EIA in 74 children. Prevalence was 11% in lower and 4% in upper respiratory tract disease (p = 0.049) without age dependency. From November to February prevalence was elevated (42/277 vs. 32/521; p < 0.001). Using serology, prevalence of acute Chlamydia infection increased with age (p < 0.001) and the number of coinfections (p < 0.001), without seasonal variation. CONCLUSION: Characteristics of C. pneumoniae carriage in the respiratory tract in childhood differ from those in systemic infection.

Adolescent↗
PubMed1985

Establishment of hybridomas secreting monoclonal antibodies to Chlamydia psittaci.

Eleven stable anti-Chlamydia hybrid clones by fusions between X63-Ag8653 myelomas and immune splenocytes from Chlamydia psittaci immunized F1 (C57BL6 X BALB/c) mice have been established which react with the 12 reference Chlamydia strains (seven C. trachomatis and five C. psittaci. Ten of these monoclonal antibodies are directed against the genera-specific epitope (40,000 MW component) for which prolonged immunization seems to be responsible.

Animals↗
PubMed1986

Rapid detection of Chlamydia psittaci in vaginal swabs of aborted ewes and goats by enzyme linked immunosorbent assay (ELISA).

An enzyme linked immunosorbent assay (ELISA) for the detection of Chlamydia psittaci in vaginal swabs of aborted ewes and goats has been developed using microtiter plates coated with sheep anti-Chlamydia immunoglobulin G. This technique was compared to the direct isolation of the agent by plaque assay on McCoy cells. Among 89 specimens from animals in infected flocks, 58 were positive by both methods, seven were only positive by ELISA, and nine others were only positive by direct isolation (plaque assay). None of the 75 specimens from animals in healthy flocks gave a positive response in ELISA or the plaque assay. Unlike direct isolation in cell culture, the ELISA technique permitted the detection of Chlamydia even in the absence of special care in sampling and conservation of specimens.

Abortion, Veterinary↗
PubMed1988

Comparison of DNA-spot hybridization, cell culture and direct immunofluorescence staining for the diagnosis of avian chlamydiae.

DNA-spot hybridization, cell culture and direct immunofluorescence staining were compared for the detection of avian Chlamydia psittaci strains in cell culture dilutions and in routine samples submitted for diagnosis. With dilutions of infected cell culture material, growth in BGM cells was by far the most sensitive technique, detecting 0.01 infected cells (20 elementary bodies) ml-1. DNA-spot hybridization and direct immunofluorescence staining were of approximately equal sensitivity, both detecting 16 infected cells (3.2 x 10(4) elementary bodies) per ml-1. When 27 avian liver and spleen samples were assayed, all 3 tests performed similarly (13 positive and 12 negative by all 3 tests). This suggests that in most avian samples presented for diagnosis, sufficient numbers of chlamydiae are present to allow any of the test to the be used. Thus, the direct immunofluorescence staining method is currently the test of choice for routine diagnosis since it is available in kit form, is relatively simple and quick to perform, and like DNA-spot hybridization, detects non-viable as well as viable organisms. However, if low levels of chlamydiae are to be effectively detected, such as in carrier birds or birds with recently acquired infections, then cell culture should be used.

Animals↗
PubMed1993

Comparison of type I and type II Chlamydia psittaci strains infecting koalas (Phascolarctos cinereus).

The native Australian marsupial Phascolarctos cinereus, otherwise known as the koala, is prone to infection by the obligate intracellular parasite Chlamydia psittaci, which causes ocular 'pink eye' and urogenital 'dirty tail' diseases. Several chlamydial DNA probes to both chromosomal and plasmid sequences were used to type by Southern blot analysis 51 samples taken from wild and captive koalas from habitats on the eastern seaboard of Australia as far apart as Queensland and Victoria. Two types of C. psittaci were observed and called types I and II. Type II was found more frequently than type I and occurred in both ocular and urogenital samples, while type I showed a strong but not absolute preference for ocular sites. Cross-hybridization analyses indicated that type I and type II had about 10% DNA sequence identity to each other. DNA analyses showed that type II was very closely related to some ovine and bovine chlamydiae but type I could not be related to any other C. psittaci strain available. Light and electron microscopic analyses of infected BGM monolayers revealed that the two strains were similar in morphological characteristics. The type I strain was considerably more infectious than the type II strain in BGM cells and in the yolk sacs of embryonated eggs. A PCR based assay detected both type I and type II koala chlamydiae in samples that had been negative by Southern blot and tissue culture and provided the first evidence that both types can occur simultaneously at the one site of infection.

Animals↗
PubMed1994

Experimental infections of pregnant sows with ovine Chlamydia psittaci strains.

Four sows were experimentally inoculated at 42 days pregnancy, with the BS isolate of Chlamydia psittaci from aborted ewes. Their body temperature and health were monitored until 30 days after farrowing. The sows seroconverted but their reproductive performance was not impaired. Chlamydiae were identified in the afterbirths from two sows with normal litters using stained smears, "Clearview" and "IDEIA" ELISA antigen detection tests. The presence of inclusion bodies was detected in sections of the infected fetal membranes after staining with haematoxylin and eosin, methylene blue and Streptavidin-Biotin using an anti-Chlamydia monoclonal antibody.

Animals↗
PubMed2006

Detection of Chlamydia pneumoniae in a bilateral orbital mucosa-associated lymphoid tissue lymphoma.

PURPOSE: To detect Chlamydia pneumoniae (C. pneumoniae) gene in a patient with bilateral orbital musoca-associated lymphoid tissue (MALT) lymphoma. DESIGN: Interventional case report. METHODS: A 47-year-old Chinese man with recurrent bilateral orbital masses underwent surgical biopsy. Ophthalmologic and radiographic examinations, routine histology, immunohistochemistry, and molecular analysis for immunoglobulin heavy chain (IgH), bcl-2/IgH gene translocation, and Chlamydia genes were performed. RESULTS: Pathology revealed orbital MALT lymphoma with B-cell monoclonality. In addition to IgH gene rearrangement, C. pneumoniae DNA was detected in the lymphoma. CONCLUSIONS: The finding of C. pneumoniae molecular signatures in this case suggests a possible association of Chlamydia and orbital MALT lymphoma. The infection may contribute to the development of the lymphoma.

Antineoplastic Agents, Alkylating↗
PubMed2003

Seroprevalence of antibodies to Chlamydia pneumoniae in women with preeclampsia.

OBJECTIVE: Preeclampsia shares many risk factors and pathophysiologic features with coronary heart disease. We studied whether, like atherosclerosis, preeclampsia is related to seroprevalence of immunoglobulin (Ig) G antibodies to Chlamydia pneumoniae. METHODS: Cross-sectional comparisons were made for 37 women with preeclampsia and 37 women with normal pregnancies at term. In these two groups, antibody titers for IgG, IgM, and IgA seroprevalence to C pneumoniae and IgG to Chlamydia trachomatis and Chlamydia psittaci were compared. RESULTS: Immunoglobulin G antibodies to C pneumoniae at a titer of at least 1:16 were more common in women with preeclampsia (25 of 37) than in women without (15 of 37) (odds ratio 3.1; 95% confidence interval 1.2, 7.9). There were no significant differences in the seroprevalence of IgA or IgM antibodies to C pneumoniae. Women with preeclampsia were also no more likely to have IgG antibodies to C trachomatis or C psittaci. CONCLUSION: Women with preeclampsia had an increased IgG seroprevalence to C pneumoniae but not to C trachomatis or C psittaci. These preliminary data suggest a specific association between infection with C pneumoniae and preeclampsia.

Antibodies, Bacterial↗
PubMed2005

[Can meningoencephalitis be caused by Chlamydiae pneumoniae?].

INTRODUCTION: Meningoencephalitis attributed to Chlamydiae pneumoniae has rarely been reported in the literature. OBSERVATION: We describe the case of a 21-year-old-man admitted for a meningeal syndrome and fever associated with respiratory symptoms and a temporal syndrome. Even though the clinical presentation and certain serological results suggested Chlamydiae infection, some of the biological data raised the possibility of Epstein Barr Virus infection. Intravenous fluoroquinolone therapy led to a successful outcome. CONCLUSION: Meningoencephalitis associated with non neurological symptoms, especially respiratory symptoms, is suggestive of Chlamydia pneumoniae infection. A broad spectrum antibiotic should be prescribed.

Adult↗
PubMed2000

Selenium and vitamin E effect on antibody production of sheep vaccinated against enzootic abortion (Chlamydia psittaci).

The effect of selenium (Se) and vitamin E (vit E) on antibody production of sheep vaccinated against Chlamydia psittaci (ovis) was investigated. Thirty-two sheep, one year old, seronegative to Chlamydia infection, vaccinated against enterotoxemia and dewormed were used. Injectable sodium selenite (0.1 mg/kg b.w.) was given twice to animals of the first group (gSe), with a three week interval. The sheep of the second group (gE) received 1 g vit E each orally, six times at weekly intervals. The animals of the third group (gSeE) were given Se and vit E in doses and routes of administration as in gSe and gE. The animals of the fourth group served as controls (gC) and injected normal saline. The first vaccination was made at the time that the second Se injection was given. Revaccination was made two weeks later. The experiment lasted 29 weeks. The results indicated that Se alone led to a significant increase of Chlamydia antibody response (P < 0.05), but not when it was given in combination with vit E. Animals that received vit E (gE) had much lower titres, just above of those of the controls.

Abortion, Veterinary↗
PubMed1999

Protection of turkeys against Chlamydia psittaci challenge by gene gun-based DNA immunizations.

Particle-mediated (Helios Gene Gun) transfer to the turkey epidermis of plasmid DNA expressing the major outer membrane protein (MOMP) of an avian Chlamydia psittaci strain was evaluated for its ability to raise an immune response and protection against challenge with the homologous strain. In turkeys, the delivery of pcDNA1/MOMP coated onto 0.6 microm gold beads was the most efficient compared to immunisations using 1.0 or 1.6 microm gold beads. The delivery of as little as 1 microg pcDNA1/MOMP coated onto 0.6 microm gold beads was efficient. Immunisation with 1.0 microm gold beads required twice more (2 microg) DNA to achieve comparable results. The use of 2 microg DNA coated onto 1.6 microm gold beads had no effects. The gene gun delivery both primed T-helper and B-cell memory although recombinant MOMP-expressing cells did not induce high-titre antibody responses. The significance of gene gun-based DNA immunisation as a means of preventing severe clinical signs, lesions and chlamydia excretion in a turkey model of Chlamydia psittaci infection was demonstrated.

Animals↗
PubMed2003

Lack of association between Chlamydia pneumoniae seropositivity and aortic atherosclerotic plaques: a population-based transesophageal echocardiographic study.

OBJECTIVES: The objective of this study was to examine the relationship between Chlamydia pneumoniae seropositivity and aortic atherosclerotic plaques in the general population. BACKGROUND: Seroepidemiologic studies suggest that C pneumoniae infection plays a role in the pathogenesis of atherosclerosis. METHODS: Transesophageal echocardiography was performed in 385 subjects (median age 66 years, range 51 to 101 years; 53% men), a sample of the Olmsted County (Minnesota) population. The association between C pneumoniae immunoglobulin (Ig) G antibody titers and aortic atherosclerotic plaques was examined. RESULTS: Chlamydia pneumoniae IgG antibodies (titers >or=1:16) were detected in 287 subjects (74.5%): low titers (1:16 to 1:32) in 58 (15.1%), intermediate titers (1:64 to 1:128) in 144 (37.4%), and high titers (>or=1:256) in 85 subjects (22.1%). Antibody titers were not associated with the presence of aortic plaques after adjustment for age, gender, and smoking status (p = 0.64). Compared with titers <1:16, the adjusted odds ratios for aortic plaques were 1.46 (95% confidence interval [CI] 0.63 to 3.42) for low titers, 1.32 (95% CI 0.68 to 2.55) for intermediate titers, and 0.94 (95% CI 0.42 to 2.07) for high titers. Among the subgroup with plaques, antibody titers were not associated with the presence of plaques >or=4 mm thick (p = 0.99), plaques >or=6 mm (p = 0.49), or mobile debris (p = 0.71), after adjustment for age and smoking. CONCLUSIONS: Chlamydia pneumoniae IgG antibody titers are not associated with the presence or severity of aortic atherosclerosis in the general population. These observations do not support a role for C pneumoniae infection in the initiation or progression of atherosclerosis.

Aged↗
PubMed1997

Lipopolysaccharide biosynthesis genes in koala type I Chlamydia: cloning and characterization.

We showed in 1988 that there are two strains of Chlamydia psittaci which infect the koala (Phascolarctos cinereus). In order to further investigate the role of these chlamydial strains in pathogenesis, we have attempted to identify genes of koala type I strain chlamydia which are involved in the immunogenic response. Transformation of Escherichia coli with a plasmid containing a 6.3-kb fragment (pKOC-10) of C. psittaci DNA caused the appearance of a specific chlamydial lipopolysaccharide (LPS) epitope on the host strain. The smallest DNA fragment capable of inducing the expression of chlamydial LPS was an XbaI fragment, 2.4 kb in size (pKOC-5). DNA sequence analysis of the complete fragment revealed regions of high identity, at the amino acid level, to the gseA genes of C. pneumoniae, C. psittaci 6BC and C. trachomatis, and the kdtA gene of E. coli which code for transferases catalysing the addition of 3-deoxy-D-manno-octulosonic acid (Kdo) residues to lipid A. Two open reading frames (ORFs) of 1,314 and 501 nucleotides in size, within the 2.4-kb fragment, were evident, and mRNA species corresponding to these ORFs were detected by Northern analysis. Both ORF1 and ORF2 are required for the appearance of chlamydia-specific LPS on the surface of recombinant E. coli.

Amino Acid Sequence↗