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[A young infant with afebrile pneumonia caused by Chlamydia trachomatis].

Pregnant women who have an urogenital Chlamydia trachomatis infection may transmit the infection to their infants. Conjunctivitis and nasopharyngeal infection are the most frequent manifestations. Less frequently the infants may develop pneumonia. We report a case of a 5-week-old girl with poor feeding, staccato cough and clinical signs of pneumonia. Chest radiography revealed severe bronchopneumonia. Despite of intravenous therapy with ampicillin and gentamicin respiration deteriorated and oxygen supplementation became necessary. After additional treatment with oral erythromycin (50 mg/kg per day) had been started the clinical condition improved. Polymerase chain reaction with a nasopharyngeal specimen was found to be positive for Chlamydia trachomatis.

Administration, Oral↗

A nationwide sentinel clinic survey of chlamydia trachomatis infection in Finland.

BACKGROUND: Chlamydia trachomatis has been recognized as a major sexually transmitted infection in North America and Western Europe during the past two decades. The incidence of C trachomatis in Finland has been continuously high throughout the 1990s. OBJECTIVES: As the epidemic of C trachomatis infection continues in Finland, there is a need to obtain up-to-date information on the prevalence and patient profiles in the planning of preventive strategies. METHODS: A nationwide sentinel clinic network consisting of seven sexually transmitted disease (STD) and five general student health clinics was established in 1995. Data were collected during a 3-year period (1995-1997) from 3,686 patients with and 32,230 patients without C trachomatis using a self-administered questionnaire. RESULTS: The prevalence of chlamydia was 8.4% in the STD clinics and 5.3% in the general clinics; 90% of the infections were endemic. The prevalence was highest in the youngest age group (15-19 years; 16% in females, 14% in males). The patients with chlamydia were significantly younger (mean age: men 26.6 years, women 23.7 years) than those without chlamydia. Women with chlamydia used oral contraceptives or intrauterine devices (IUD) significantly more often (59%) than women without chlamydia (42%). A high number of sex partners and a history of previous chlamydia during the preceding 12 months were also risk factors. Men contracted chlamydia frequently from a casual partner (61%) but rarely from a commercial sex worker (2%). For women, the source partner was most often a regular one (61%). The median time from exposure to attendance was 34 days, and was highest when the source partner was a spouse. One third of the patients could have spread chlamydia to a new partner before the diagnosis. CONCLUSIONS: C trachomatis infection is spread all over Finland, and the risk factors include younger age, high number of sex partners, and use of oral contraceptives or IUDs. Source partner analysis focused attention on the importance of transmission from regular partners, especially in women. The time from transmission to diagnosis was long, and any effort to shorten this period would be an effective preventive strategy.

Adolescent↗

Pneumonia associated with Chlamydia trachomatis infection in an infant.

Chlamydia trachomatis was isolated from the epipharynx of a 10-week-old baby girl taken ill with pneumonia but without signs of conjunctivitis. The infant developed specific antibodies to the organism. The course of the pneumonia was protracted, with cough and tachypnea. The baby, who was afebrile, improved on antibiotic therapy but pulmonary infiltrates persisted for several months. To our knowledge, this is the first case of pneumonia in an infant associated with C. trachomatis infection reported elsewhere than North America.

Chlamydia Infections↗

Frequency of antigen-specific B cells during experimental ocular Chlamydia trachomatis infection.

Chlamydia-specific antibody-secreting cells have been identified in conjunctiva and draining cervical lymph nodes by an ELISPOT assay in a cynomolgus monkey model of trachoma. These local sites contained numbers of chlamydia-specific B cells that were higher than those in distant inguinal lymph nodes and peripheral blood. The numbers of chlamydia-specific immunoglobulin G-secreting B cells observed were 5 to 57 per 10(6) cells in conjunctiva and 24 to 996 per 10(6) cells in cervical lymph nodes during conjunctival infection or after challenge of immune monkeys with the chlamydial 57-kDa heat shock protein (hsp60). These studies demonstrate a large chlamydia-specific B-cell component in the conjunctiva during ocular chlamydial infection. These results are similar to our findings for chlamydia-specific T-cell responses.

Animals↗

Purification and partial characterization of the major outer membrane protein of Chlamydia trachomatis.

Elementary bodies (EB) of Chlamydia trachomatis serotypes C, E, and L2 were extrinsically radioiodinated, and whole-cell lysates of these serotypes were compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Autoradiography of the polypeptide profiles identified a major surface protein with an apparent subunit molecular weight of 39,500 that was common to each C. trachomatis serotype. The abilities of nonionic (Triton X-100), dipolar ionic (Zwittergent TM-314), mild (sodium deoxycholate and sodium N-lauroyl sarcosine), and strongly anionic (SDS) detergents to extract this protein from intact EB of the L2 serotype were investigated by SDS-PAGE analysis of the soluble and insoluble fractions obtained after each detergent treatment. Only SDS readily extracted this protein from intact EB. Sarkosyl treatment selectively solubilized the majority of other EB proteins, leaving the 39,500-dalton protein associated with the Sarkosyl-insoluble fraction. Ultrastructural studies of the Sarkosyl-insoluble EB pellet showed it to consist of empty EB particles possessing an apparently intact outer membrane. No structural evidence for a peptidoglycan-like cell wall was found. Morphologically these chlamydial outer membrane complexes (COMC) resembled intact chlamydial EB outer membranes. The 39,500-dalton outer membrane protein was quantitatively extracted from COMC by treating them with 2% SDS at 60 degrees C. This protein accounted for 61% of the total COMC-associated protein, and its extraction resulted in a concomitant loss of the COMC membrane structure and morphology. The soluble extract obtained from SDS-treated COMC was adsorbed to a hydroxylapatite column and eluted with a linear sodium phosphate gradient. The 39,500-dalton protein was eluted from the column as a single peak at a phosphate concentration of approximately 0.3 M. The eluted protein was nearly homogeneous by SDS-PAGE and appeared free of contaminating carbohydrate, glycolipid, and nucleic acid. Hyperimmune mouse antiserum prepared against the 39,500-dalton protein from serotype L2 reacted with C. trachomatis serotypes Ba, E, D, K, L1, L2, and L3 by indirect immunofluorescence with EB but failed to react with serotypes A, B, C, F, G, H, I, and J, with the C. trachomatis mouse pneumonitis strain, or with the C. psittaci feline pneumonitis, guinea pig inclusion conjunctivitis, or 6BC strains. Thus, the 39,500-dalton major outer membrane protein is a serogroup antigen of C. trachomatis organisms.

Antigens, Bacterial↗

Need for screening for genital Chlamydia trachomatis infection in Australia.

Genital Chlamydia trachomatis is the most common notifiable sexually transmissible infection in Australia and is associated with significant complications, particularly for women. There is no screening program for chlamydia in Australia despite this infection fulfilling the criteria for screening--it is easily diagnosed with acceptable self-administered tests and early treatment prevents complications. Screening for chlamydia reduces the prevalence of infection and the rate of complications and is recommended by several Western countries including the United States, England and Canada. If a screening program was introduced in Australia, several issues would first need to be addressed including who would be screened, how often would they be screened and where would screening be offered. We discuss these issues in this paper in an effort to advance the debate and the introduction of chlamydia screening in Australia.

Adolescent↗

Opportunistic screening of young men for urogenital Chlamydia trachomatis infection in general practice.

Chlamydia trachomatis is a widespread, sexually transmitted infection causing pelvic inflammatory disease, infertility, ectopic pregnancy and chronic pelvic pain among women. Asymptomatic infections among men contribute significantly to maintaining the spread of the infection. In a 1-y intervention study in general practices we aimed to evaluate an opportunistic screening programme targeting 16-25-y-old men. When the young men saw their general practitioner (GP) for the first time during the intervention y, they were offered a test for C. trachomatis based on a first catch urine sample. Main outcome measures were percentage of tested men and prevalence of infection in the intervention practices compared with the test activity in the rest of the county during the intervention y and the y before. GPs in the intervention practices saw 617 (75.6%) of the 814 registered young men during the intervention period. Screening was offered to 300 (48.6%) and 219 (26.9% of the target population) accepted the invitation. The prevalence of infection among screened men was 5.0%. We conclude that opportunistic screening for urogenital C. trachomatis infection in general practice is feasible.

Adolescent↗

Isolation and molecular characterization of the ribosomal protein L6 homolog from Chlamydia trachomatis.

The cloning of a Chlamydia trachomatis eukaryotic cell-binding protein reported earlier from our laboratory (R. Kaul, K. L. Roy, and W. M. Wenman, J. Bacteriol. 169:5152-5156, 1987) represents an artifact generated by nonspecific recombination of chromosomal DNA fragments. However, the amino terminus of this plasmid-encoded fusion product demonstrated significant homology to Escherichia coli ribosomal protein L6. By using a 458-bp PstI-HindIII fragment of recombinant pCT161/18 (representing the 5' end of the cloned gene), we isolated and characterized a C. trachomatis homolog of the ribosomal protein L6 gene of E. coli. Sequence analysis of an 1,194-bp EcoRI-SacI fragment that encodes chlamydial L6 (designated CtaL6e) revealed a 552-bp open reading frame comprising 183 amino acids and encodes a protein with a molecular weight of 19,839. Interestingly, complete gene homology between C. trachomatis serovars L2 and J, each of which exists as a single copy per genome, was observed. Expression of a plasmid-encoded gene product is dependent on the lac promoter, since no product was obtained if the open reading frame was oriented in opposition to the lac promoter. Immunoblotting of purified ribosomes revealed functional, as well as antigenic, homology between the E. coli and C. trachomatis ribosomal L6 proteins.

Amino Acid Sequence↗

[The significance of Chlamydia trachomatis in chronic infectious urethro-adnexitis in the male].

The causative significance of chlamydia trachomatis in chronic urethra-prostatitis can be assumed because of the high incidence in non-gonorrheal and post-gonorrheal urethritis and epididymitis. 158 men with chronic inflammatory urethro-prostatitis were reviewed. In 32.3% the urethral smear and in 29.7% the prostatic fluid were positive for chlamydia trachomatis. Simultaneously leucocyte count and pH of the prostatic fluid as well as the immunoelectrophoresis of the ejaculate were investigated. The correlation of these results with positive chlamydia trachomatis findings demonstrates the significant role of chlamydia trachomatis in chronic inflammatory processes of the urethra and prostate.

Adult↗

Molecular cloning of the major outer membrane protein of Chlamydia trachomatis.

A gene library of Chlamydia trachomatis (serovar L1) DNA has been prepared in the phage vector lambda 1059. From this bank, 20 recombinant phage-expressing components which reacted with serum from a patient with a C. trachomatis (L1) infection were chosen. Selective expression and radiolabeling of phage polypeptides in irradiated Escherichia coli demonstrated that one of these clones encoded a polypeptide doublet with an apparent molecular weight similar to that of the C. trachomatis (L1) major outer membrane protein. Both species of this cloned doublet (40 and 41 kilodaltons) could be immunoprecipitated by serum from a patient with a C. trachomatis (L1) infection but not by normal human serum. Components of this apparent molecular weight were not precipitated from irradiated E. coli infected with vector phage lambda 1059 by either of these sera. Comparison of the Staphylococcus aureus-V8 protease peptide maps of these two cloned polypeptides and chlamydial major outer membrane protein extracted from elementary bodies showed all three polypeptides to produce peptide fragments of 15.5, 13.8, and 11.5 kilodaltons. Due to the identical apparent molecular weights of the fragments produced from the 40- and 41-kilodalton cloned polypeptides, these were concluded to be different conformational forms of the same molecular species. These cloned components were indistinguishable from C. trachomatis (L1) major outer membrane protein.

Antigens, Surface↗

Characterization of two conformational epitopes of the Chlamydia trachomatis serovar L2 DnaK immunogen.

Chlamydia trachomatis DnaK is an important immunogen in chlamydial infections. DnaK is composed of a conserved N-terminal ATP-binding domain and a variable C-terminal peptide-binding domain. To locate the immunogenic part of C. trachomatis Dnak, we generated monoclonal antibodies (MAbs) against this protein. By use of recombinant DNA techniques, we located the epitopes for two MAbs in the C-terminal variable part. Although the antibodies reacted in an immunoblot assay, it was not possible to map the epitopes completely by use of 16-mer synthetic peptides displaced by one amino acid corresponding to the C-terminal part of C. trachomatis DnaK. To determine the limits of the epitopes, C. trachomatis DnaK and glutatione S-transferase fusion proteins were constructed and affinity purified. The purified DnaK fusion proteins were used for a fluid-phase inhibition enzyme-linked immunosorbent assay with the two antibodies. The epitopes were found not to overlap. To obtain DnaK fragments recognized by the antibodies with the same affinity as native C. trachomatis DnaK, it was necessary to express, respectively, regions of 127 and 77 amino acids. The MAbs described in this study thus recognized conformational epitopes of C. trachomatis DnaK.

Adenosine Triphosphatases↗

Evaluation of enzyme immunoassay for the detection of anogenital infections caused by Chlamydia trachomatis.

BACKGROUND--Infection caused by Chlamydia trachomatis is now recognised as the most prevalent sexually transmitted disease in many parts of the world. Anorectal infections caused by C. trachomatis is not uncommon. Enzyme-linked immunoassay (EIA) detects an antigen lipopolysaccharide (LPS) of C. trachomatis directly in clinical specimens. OBJECTIVE--Our aim was to compare an enzyme immunoassay, Wellcozyme Chlamydia (WZ04) with cell culture for the diagnosis of chlamydial infection of the anogenital tract. METHOD--Rectal swabs were taken from 100 prostitutes (80 females and 20 males) for chlamydia culture, WZ04 and direct immunofluorescence (DIF). In addition, endocervical specimens were obtained from the females for the above three tests. MAIN FINDINGS--All the positive rectal specimens were from females. Nine patients had a positive chlamydia culture from the rectum but negative WZ04 and DIF. Two patients had false positive results by WZ04 but negative culture and DIF. For cervical specimens, WZ04 identified 43% (3/7) of the culture positive cases. Specificity was 98.6%. WZ04 identified an additional specimen as positive which was also confirmed as positive by DIF. CONCLUSION--Our study shows that in our hands enzyme-linked immunoassays such as Wellcozyme Chlamydia are neither sensitive nor specific in detecting C. trachomatis infection of the rectum. For cervical infections, the sensitivity of WZ04 was 43% and the specificity 98.6% as compared to culture, with a positive predictive value of 75% and a negative predictive value of 94.7%.

Adult↗

Illnesses in infants born to women with Chlamydia trachomatis infection. A prospective study.

Chlamydia trachomatis is known to cause infant pneumonitis and conjunctivitis and is a suspected cause of otitis media and gastroenteritis. To identify infections associated with exposure to C trachomatis, infant illnesses were studied through a "blinded" review of medical records of 244 infants born to women cultured antenatally for cervical C trachomatis, 25% of whom had C trachomatis-positive cultures. Compared with unexposed infants, infants exposed to C trachomatis had twice the rate of both pneumonitis and recurrent otitis media in the first six months. Infants who were exposed to C trachomatis and who had pneumonitis had higher subsequent rates of gastroenteritis than either unexposed infants or exposed infants without pneumonitis. These results suggest that appreciable outpatient infant morbidity may be associated with maternal infection with C trachomatis, and that it may either cause or promote the occurrence of early, recurrent otitis media and gastroenteritis.

Bronchitis↗

Evaluation and comparison of tests to diagnose Chlamydia trachomatis genital infections.

Infection with Chlamydia trachomatis results in intracytoplasmic inclusions and the generation of infectious elementary bodies (EBs). These can be detected by various procedures. Staining of epithelial cells with vital dyes was first used to detect inclusions, but is insensitive. Thus, Papanicolaou-stained cervical smears cannot be recommended. The advent of the ability to grow chlamydiae in cultured cells over 30 years ago had a major impact on chlamydial research and on detection. However, this procedure is probably <70% sensitive for cervical infection and less for urethral infection in men and is now practised infrequently following the advent of other, mostly less laborious and often equally, or more sensitive detection systems. Thus, staining a smear with a specific fluorescent monoclonal antibody to detect EBs is simple and the direct fluorescent antibody tests became a commercial proposition in the early to mid-1980s. Nevertheless, although highly sensitive and specific in competent hands, technical expertise is crucial and even the most experienced may be unable to read a large number of stained smears on slides quickly. In view of this, it is understandable that enzyme-linked immunosorbent assays (ELISAs) gained popularity from the mid-1980s onwards, for they are not very labour intensive and their reading is neither subjective nor tedious. Unfortunately, these aspects outweighed the fact that the ELISAs lack sensitivity, some being very insensitive. The situation has been rescued, however, by the advent in the early 1990s of methods that amplify chlamydial DNA, making it easily detectable by relatively simple procedures. The polymerase chain reaction is such a method and has high specificity and sensitivity, although commercial development has so far not met the high standard expected of it in terms of sensitivity. The ligase chain reaction does not invoke such criticism, and high values for both sensitivity and specificity may be expected, even on urine samples. This augers well for diagnosing an infected individual patient and for effective screening programmes. Antibody tests have no place in a screening programme and are of debatable value in diagnosis.

Chlamydia Infections↗

Chemokine bioactivity of RANTES is elevated in the sera of infertile women with past Chlamydia trachomatis infection.

PROBLEM: It has been shown that Chlamydia trachomatis infection in infertile women is highly associated with tubal pathology. Chlamydia trachomatis antibody testing is a simple screening test for tubal factor subfertility, however, it is based on the detection of previous infection. Recently, association between some inflammatory diseases and chemokines has been investigated. This study was performed to clarify the relationship between chemokines in the sera of infertile women and past C. trachomatis infection. METHOD OF STUDY: Serum samples were collected from 10 infertile women having C. trachomatis antibodies [immunoglobulin (Ig)G and/or IgA] in their sera and 10 infertile women without the antibodies. All patients' tubo-ovarian structures were explored by transvaginal hydrolaparoscopy (THL). A CXC chemokine, interleukin-8, and six CC chemokines including macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, monocyte chemotactic protein-1 (MCP-1), MCP-3, eotaxin, and regulated on activation, normal T cell expressed and secreted (RANTES) concentrations in their sera were analyzed using enzyme-linked immunosorbent assay. RESULTS: The serum concentration of RANTES was significantly higher in patients with C. trachomatis antibodies than those without the antibodies (P = 0.019). However, there were no significant differences of the concentrations of other chemokines between the sera of infertile women with and without C. trachomatis antibodies. The concentration of RANTES in the sera of infertile women did not correlate with C. trachomatis antibody titers or tubal pathology diagnosed by THL. CONCLUSIONS: These findings might indicate significant roles of some chemokines in the pathogenesis of C. trachomatis infection. Further studies are necessary to study the usefulness of evaluations of chemokines in tubal infertility investigations.

Adult↗

Chlamydia trachomatis infections: a clinical update.

Chlamydia trachomatis has emerged as the most common sexually transmitted pathogen in the United States and in many other countries. Because of its increasing importance, the authors present an update on chlamydial infections.

Adolescent↗

Sampling and specimen handling in the diagnosis of genital Chlamydia trachomatis infections.

In isolation of Chlamydia trachomatis, special consideration must be paid to the sampling technique, the type and quality of the sampling swab used, and the manner in which transport and storage of specimens are performed. The use of cotton-tipped swabs with aluminum shafts (E.N.T.) rather than calcium alginate-treated endourethral swabs (Calgiswabs), resulted in a higher frequency of isolation of C. trachomatis from clinical specimens. E.N.T. swabs were also preferable to cotton-tipped wooden swabs. In conformity with that finding, a higher chlamydial inclusion count was obtained in cultures of experimentally infected samples stored in contact with such swabs. The percentage of surviving C. trachomatis organisms after storage in transport medium (2-SP) for 2 days at room temperature, or 4 days at 4 degrees C, suggested that such sample storage should be acceptable in the routine diagnosis of genital chlamydial infections.

Chlamydia Infections↗