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F Eb

Publications and source records attributed to F Eb.

At least 37 records · Page 2Linked to original sources

Chlamydia trachomatis and male infertility in Tunisia.

OBJECTIVE: Chlamydia trachomatis is a common sexually transmitted micro-organism. The impact of chlamydial infection on semen parameters and male fertility is controversial. Our purpose was to determine the prevalence of C. trachomatis in the male partners of infertile couples in Tunisia and to assess the relationship between chlamydial infection markers and male infertility. METHODS: Chlamydial DNA in urethral and in semen specimens was determined by using the Cobas Amplicor polymerase chain reaction (PCR) assay and chlamydial immunoglobulin G (IgG) antibodies were measured by micro-immunofluorescence in serum samples in 92 male partners, with or without pathological standard semen parameters, according to the guidelines of the World Health Organization (sperm count, progressive sperm motility, sperm morphology and sperm viability). In parallel, chlamydial infection markers in endocervical material were determined by PCR and chlamydial IgG antibodies were measured by micro-immunofluorescence in serum samples from the female partners of the patients. RESULTS: C. trachomatis was found in 35.9% (33/92) of the male partners of the infertile couples and in 38% (35/92) of their female partners. There was a significant correlation between the detection of C. trachomatis in both partners (p = 0.004). C. trachomatis DNA was detected in 18.5% (17/92) of urethral specimens and in 16.3% (15/92) of semen specimens. Chlamydial IgG antibodies were present in 9.8% (9/92) of the serum samples. A standard semen analysis showed that 88% (81/92) were pathological. Sperm viability, progressive sperm motility, morphology and sperm concentration were abnormal in 73.8%, 70.2%, 34.5% and 13%, respectively, of the 92 evaluated semen specimens. Comparison of the parameters of the standard semen analysis between the male partners of the infertile couples with or without chlamydial infection markers showed that only the presence of C. trachomatis DNA in semen samples can affect sperm motility. Parameters of the standard semen analysis were not significantly related either to the detection of chlamydial DNA in urethral samples or to the presence of serum chlamydial antibodies. CONCLUSION: Our results show that C. trachomatis seems to be widespread among the male partners of infertile couples in Tunisia and show that this organism can affect sperm motility and, thus, can play an important role in the etiology of male infertility.

Adult↗

Epidemiological study of an Acinetobacter baumannii outbreak by using a combination of antibiotyping and ribotyping.

From June to November 1994 (period 1) and from February to June 1995 (period 2), multiresistant Acinetobacter baumannii strains were isolated in intensive care units and surgical wards of the Amiens Teaching Hospital Center (Amiens, France). Eighteen isolates were obtained from 17 (1%) of 1,706 patients admitted during both of these periods, giving an incidence rate of nosocomial infection per 1,000 patient days of 0.6%. Of 17 infected patients, 9 had pneumonia, 3 had urinary tract infection, 2 had peritonitis, 1 had septicemia, 1 had a catheter infection, and 1 had pneumonia and urinary tract infection. According to typing results, four antibiotic resistance profiles were detected: a, b, c, and d; seven ribotypes were distinguished by both restriction enzymes EcoRI and SalI (A, B, C, D, E, F, and G). By combining antibiotyping and ribotyping, we obtained eight groups of strains (groups I to VIII). Group I contained five strains (strains 4, 5, 7, 8, and 9) which had antibiogram pattern a and ribopattern A and constituted the outbreak strains. The strains of group II (strains 3, 10, 11, 13, and 14) were closely related to outbreak strain A and appeared to be variants of ribotype A (A2 [strain 3]; A4 [strain 10]; A5 [strains 11, 13, and 14]). Groups III, IV, V, VI, VII, and VIII included strains which were epidemiologically unrelated to the strains of group I and were considered nonoutbreak strains.

Acinetobacter↗

[Prevalence of anti-Chlamydia pneumoniae antibodies in preadolescent children in Congo].

Chlamydia pneumoniae (CPn) is recognised as a common cause of both upper and lower respiratory tract infections. Seroepidemiological studies seem to indicate a world-wide distribution of this organism. In order to evaluate the prevalence of antibodies to CPn in a healthy pediatric population, we measured anti-C. pneumoniae antibodies in a group of 253 infants without respiratory tract infections, aged from 1 to 12 years. Sera were obtained from children seen at immunization clinics and schools in Lubumbashi (Congo). Antibodies to CPn were evaluated using micro-immunofluorescence assay. IgG antibody to CPn in a titre 16 was considered as positive. The antibody prevalence was found to be 25.7%. This prevalence was 6.2% in children aged from 1 to 6 years, and 37.8% in children aged from 7 to 12 years. It was less than 10% under five years, increasing to 50% at 12 years. The progressive increasing of seropositivity related to age suggests that reinfections may be frequent. This study shows an important spread of this bacteria in the preadolescent population of an African country.

Antibodies, Bacterial↗

Sequence analysis of the NS5A protein of European hepatitis C virus 1b isolates and relation to interferon sensitivity.

Japanese studies have defined the discrete 2209-2248 amino acid region of the non-structural 5A protein (NS5A(2209-2248)) of hepatitis C virus genotype 1b (HCV 1b) isolates as the interferon sensitivity determining region (ISDR). European studies did not confirm these results since most of the ISDR sequences harboured an intermediate profile. Recently, a direct interaction between the NS5A protein, involving the ISDR, and the interferon-induced protein kinase (PKR) has been reported and presented as a possible explanation of HCV interferon resistance. In the present study, the entire NS5A amino acid sequence from 11 resistant and eight sensitive strains from European HCV 1b isolates was inferred from direct sequencing. The previously described important amino acid stretches and positions in NS5A were compared between the resistant and sensitive groups. Although some variations were observed, no clear differences could be directly correlated with the interferon sensitivity. However, sensitive strains were different, owing to more amino acid changes when compared to a consensus sequence from all strains. The carboxy-terminal region and especially the previously reported NS5A/V3 region showed most of the variations. Moreover, the conformational analysis of NS5A by secondary structure prediction allowed the differentiation of most sensitive strains from resistant ones. It was concluded that other regions different from ISDR were involved in resistance to interferon maybe via the interaction between NS5A and PKR.

Amino Acid Sequence↗

[Direct cost of antibiotic therapy prescribed for nosocomial bacteremia. Prospective study during 6 months at a CHU (University Hospital Center)].

A six-month prospective study of costs associated with antimicrobial therapy in nosocomial bacteremia was conducted from November 1, 1995 to April 30, 1996 in a 1837-bed teaching hospital, with the help of the hospital pharmacists and hospital hygiene unit. Only the costs due to the antimicrobials themselves were taken into account. A total of 238 cases of nosocomial bacteremia occurred during the study period. The total direct cost of antimicrobial therapy was 444,931 French francs (FF), i.e., 6.8% of total expenditures for antimicrobials. Mean cost per case was 1869 FF, and was 2.6-fold higher in the 21 patients with bacteremia due to more than one organism (P = 0.03). CAses with an identifiable portal of entry contributed 75% of the total cost. Portals of entry associated with the highest cost included central venous lines (103,928 FF) and urinary tract infections (50,810 FF). Although 20% of nosocomial bacteremias due to coagulase-negative staphylococci did not lead to antimicrobial therapy, the remaining 80% contributed 40.8% of the total cost, followed by nosocomial bacteremias due to Escherichia coli with 19.7% of the total cost. Thirty-seven patients (15.5%) did not receive specific antimicrobial therapy, for the following reasons: death before treatment initiation, transfer to another hospital, antimicrobial therapy initiated earlier for another infection elsewhere in the body due to a different organism, or other form of treatment. The results of this study highlight the need for prevention.

Anti-Bacterial Agents↗

Capture-ELISA: a new assay for the detection of immunoglobulin M isotype antibodies using Chlamydia trachomatis antigen.

We present here a new method of IgM antibody-capture enzyme-linked immunosorbent assay (IgM-Capture-ELISA) for the diagnosis of recently acquired infections with Chlamydia trachomatis. For this analysis, plates were coated with goat IgG anti-human Fc mu. The capture of serum IgM antibodies was revealed indirectly by the sequential addition of biotinylated chlamydial proteins and peroxidase-conjugated streptavidin. In chlamydial extracts, cysteine-rich proteins are preferential antigenic targets for the humoral response. 3-(N-maleimidopropionyl)-biocytin (MPB), which binds biotinylated moieties to sulfhydryl groups, was used for the labeling procedure. The preservation of the antigenic specificity of labeled proteins was controlled by a blotting of these proteins, which were, respectively, probed either with specific IgM antibodies or with streptavidin. This analysis revealed that, after labeling, recognized epitopes are more particularly present on the major outer membrane protein (MOMP) of Chlamydia trachomatis. The validation of IgM-Capture-ELISA was assessed by using 170 selected sera from patients suspected of being infected by Chlamydia. Results were respectively compared to conventional indirect immunofluorescence assays (MIF-IgM assays) and to Western blotting. Sixteen sera were found to possess IgM antibodies against Chlamydia trachomatis with IgM-Capture-ELISA. Among these 16 sera, 14 and 15 were, respectively, positive with MIF-IgM assays and in Western blotting. Data obtained with IgM-Capture-ELISA reveal the absence of false-positive results in sera containing rheumatoid factor, which has been shown to interfere in the two other methods. IgM-Capture-ELISA value was then confirmed using sera from patients consulting for genital or pulmonary diseases, from patients with confirmed chlamydial infections, and from patients with other pathologies. IgM-Capture-ELISA appears as an alternative simple semi-quantitative assay for the detection of early chlamydial infection.

Animals↗

Direct blotting electrophoresis for sequencing and genotyping hepatitis C virus.

Many methods have been used to differentiate the hepatitis C virus (HCV) genotypes based on, for example, type specific primers, probes and restriction fragment length polymorphism. However, determination of the nucleotide sequence remains the reference. Therefore, a simple non-radioactive cycle sequencing technique was developed for clinical tests. PCR-amplified products of the 5' non-coding region (from position -274 to -31) were sequenced using a 5' digoxygenin-labeled primer. After denaturation, the samples were loaded on a direct blotting electrophoresis system (GATC 1500). Sequencing products were blotted onto a nylon membrane during the electrophoresis. The DNA fragments were then UV-cross-linked, incubated with phosphatase-labeled anti-digoxygenin antibody and stained with a precipitating substrate. Reading the sequence of six samples were possible within 2 days. In 41 different samples, five different genotypes were found by sequence analysis from position -245 to -69, of which 17 were type 1a, 7 type 1b, 5 type 2a, 8 type 3a, 3 type 4 and 1 type 5. These results agreed with those obtained by reverse hybridization assay. Direct blotting electrophoresis offered a good non-radioactive method of performing clinical sequencing on a medium scale, with a minimum of investment.

Adult↗

Comparison of hepatitis C virus serotyping and genotyping in French patients.

BACKGROUND: Hepatitis C virus (HCV) serotyping has been proposed as an alternative assay to determine the respective genotype as it is more rapid, simple and less expensive than polymerase chain reaction (PCR) based typing methods. OBJECTIVES: A serotyping assay was compared with a genotyping assay to determine the infecting hepatitis C virus type in chronically HCV infected patients eligible for interferon therapy. STUDY DESIGN: An enzyme immunoassay (HC01, Murex) was tested to identify HCV types 1, 2 and 3 specific antibodies in 134 PCR-positive sera from chronically infected patients which had been previously genotyped by a reverse hybridization assay (INNO-LiPA HCV I, Innogenetics). Respectively nine and seven sera were from HIV-seropositive and hemodialysis patients. Unreactive sera and those with discrepant results were retested by a new version (HC02) extended to types 4, 5 and 6. RESULTS: The distribution frequency of HCV genotypes was subtype 1a, 16.4%; subtype 1b, 46.3%; subtype 2a, 7.5%; subtype 3a, 20.9%; type 4, 4.5%; type 5, 0.7%; and co-infections, 3.7%. Among all the patients, 95% were of type 1, 2 or 3. The antibody reactivities of hemodialysis (1/7; P < 0.05) and HIV-seropositive patients (4/9; P = 0.06) were lower than for the patients seen at the hepatology unit (87/118). For these latter patients, the serotyping assay was interpretable in 71% and concordant in 64% of the samples with the genotyping assay. Out of the 84 samples with interpretable results, 75 sera were correctly serotyped (89% specificity). The two mixed results obtained by serotyping did not correspond to genotype co-infections (n = 3) and reciprocally. Six discrepancies were ruled out by the new assay, but the 2 untypeable sera remained unsolved, and four out of six sera with genotype 4 were serotyped as type 5. CONCLUSIONS: Serotyping could be an attractive approach if the reactivity was improved and the subtyping possible.

Adult↗

Serological cross-reactions between Bartonella and Chlamydia species: implications for diagnosis.

Diagnosis of Chlamydia or Bartonella infections continues to rely mainly on serology. However, serological cross-reactions between members of these genera have recently been described. Sera from eight patients originally diagnosed as having Chlamydia pneumoniae endocarditis reacted with both Chlamydia sp. and Bartonella quintana antigens (microimmunofluorescence technique). Adsorption of sera with B. quintana or C. pneumoniae antigens removed anti-C. pneumoniae antibodies, whereas adsorption with C. pneumoniae antigens did not change antibody titers to B. quintana. Western blot analysis confirmed the presence of cross-reacting antigens and showed antibody patterns in all sera to be compatible with a Bartonella infection. These patients were therefore probably suffering from Bartonella-induced rather than Chlamydia-induced endocarditis. In contrast, sera from 10 patients presumed to be suffering from C. pneumoniae pneumonia did not display anti-B. quintana antibodies, although cross-reacting antigens were revealed by Western blotting. This work highlights the possibility that cases of infective Bartonella endocarditis are erroneously diagnosed as chlamydial infections.

Adsorption↗

Genotyping of Portuguese Chlamydia trachomatis urogenital isolates.

OBJECTIVE: To determine the prevalence of the different Chlamydia trachomatis genotypes in Portuguese patients. METHODS: Urogenital isolates (n = 240) derived from attenders of various clinics in the Lisbon area were differentiated into genovars by genotyping with restriction fragment length polymorphism (RFLP) analysis of the PCR amplified omp1 gene. RESULTS: Genotype E was the most common for both men (47.9%) and women (43.8%). Genotypes D and F were the second most prevalent for men (11.3%) and genotype H was the second most prevalent for women (19.5%). Genotypes F, G, D, in women and H, G, I, in men, were found in a lower percentage of cases. Genotypes B, Ba, J, K, L1 and L2 were very rarely detected. CONCLUSIONS: With one exception, the overall distribution of Chlamydia trachomatis genotypes in our study is similar to what has been observed in other western countries. The only exception is the unusual prevalence of genotype H among women. The clinical manifestations associated with this and other genotypes were similar.

Adult↗

[Research of type 1, 2 and 3 hepatitis C virus specific antibodies in relation to the viral genotype in chronically infected patients].

The determination of the viral genotype in chronically HCV infected patients is used as an epidemiologic tool, a predictive marker of the evolution of the disease and especially of the response to the interferon alfa therapy. Its determination needs an amplification of the selected genomic region and remains expensive. Thus an indirect determination of the genotype has been proposed using the characterization of type-specific antibodies. In 101 chronically HCV infected patients, a serologic method specific for HCV type 1, 2 and 3 has been evaluated in relation to the genotyping one. The test was interpretable in 64 sera and in agreement with the genotyping method in 92% of the samples. The reactivity of the test was lower in hemodialysis and IVDUs patients (p < 0.02). The mixed results obtained by the serologic typing method were not in agreement with the results of the genotyping coinfections. We could not differentiate the possible past infections from the cross-reactivities of the test. The serotyping methods was simple and rapid, allowing generally a deduction of the viral genotype. It could be an attractive approach if the reactivity was improved and the subtyping was possible.

Adult↗

Limits of the microimmunofluorescence test and advantages of immunoblotting in the diagnosis of chlamydiosis.

The Western blot (immunoblot) patterns of 56 serum specimens, all examined previously by the microimmunofluorescence (MIF) test for species-specific Chlamydia antibodies, were analyzed. Predominant specific-antibody activity was directed to the 170-, 155-, 145-, 120-, 115-, 100-, 57-, and 38-kDa proteins of Chlamydia trachomatis and to the 175-, 130-, 110-, 98-, and 30-kDa proteins of Chlamydia pneumoniae. All of these antigens appeared to be species specific. The reactivity with 90-, 80-, 75-, 62- or 60-, and 55-kDa proteins and the major outer membrane protein appeared to be genus specific. Fourteen serum samples which had identical titers of immunoglobulin G as determined by the MIF test were investigated by Western blotting. We found that nine serum samples had anti-C. trachomatis protein profiles and two had anti-C. pneumoniae protein profiles. The double seropositivity observed by MIF corresponded with cross-reactivity to genus-specific antibodies. As for the three remaining serum specimens, we observed identical protein profiles for C. trachomatis and C. pneumoniae, confirming the double seropositivity experienced with the MIF test. Western blotting can differentiate between specific reactions and interfering noise from other, partly cross-reacting chlamydial species.

Antibodies, Bacterial↗

Usefulness of omp1 restriction mapping for avian Chlamydia psittaci isolate differentiation.

Sixty-five avian Chlamydia psittaci isolates collected worldwide, including 27 previously characterized reference strains, were analysed by restriction mapping of the major outer membrane protein gene (omp1) obtained after DNA amplification by PCR. They were compared to 2 ruminant isolates, a feline pneumonitis and a guinea pig inclusion conjunctivitis (GPIC) isolate. According to their omp1 restriction patterns, avian strains were heterogeneous in that they exhibited 6 and 4 distinct patterns using AluI and MboII restriction enzymes, respectively, thus defining 7 groups. However, 84% of the studied strains belonged to groups 1 to 4, which share a specific fragment triplet of 411, 282 and 102 base pairs in their AluI digestion patterns. Comparisons with serological classifications showed a strict correlation and allowed further intraserovar differentiation. Furthermore, this classification based upon a single gene (omp1) roughly correlated with the data obtained by RFLP of native DNA and DNA/DNA hybridization studies. There was no host or geographic specificity in the pattern exhibited by these strains. The ruminant, feline pneumonitis and GPIC C. psittaci isolates were clearly distinguished from each other and the avian strains. Moreover, this method was clearly able to identify dubiously designated strains as well as mixtures of isolates within a single sample. In conclusion, this PCR approach based upon omp1 restriction mapping enables the differentiation of avian C. psittaci isolates and can be proposed as a taxonomic and epidemiologic tool.

Animals↗

[Retrospective analysis of 1331 samples of cerebrospinal fluid in newborn infants with suspected infection].

BACKGROUND: Definitive diagnosis of a neonatal infection usually requires recovery of an etiologic agent from body fluids or tissues such as spinal fluid, blood and urine. Routine lumbar puncture (LP) may raise some problems in interpreting results. POPULATION AND METHODS: A retrospective analysis of 1331 samples of CSF was made. LP had been performed on 1041 neonates including 569 prematures (54.6%) as a part of the evaluation for suspected bacterial infection. RESULTS: In 50.7% of the cases, the CSF was haemorrhagic. The frequency of traumatic taps increased with the degree of prematurity, low birth weight, precocity of LP, association with respiratory distress and disorders of coagulating factors. In addition, haemorragic taps modified biochemical and cytologic characteristics of CSF. One hundred and six (8%) CSF samples contained organisms but the diagnosis of meningitis was certain in only 23 cases (2.2%). In the other 83 cases, CSF was thought to be contaminated, mostly by coagulase-negative staphylococci. Since both blood and CSF cultures were positive for the same bacterial organism in 18 cases, it was concluded that the LP had been useful in identifying the pathogens in only five cases. The high frequency of contaminated CSF led to overestimation of the incidence of true bacterial meningitis (0.57% in our study). CONCLUSIONS: The low incidence of meningitis in neonates, the risk of having an haemorragic tap associated with the possibility of clinical aggravation during LP and the fact that the same pathogen is frequently (78.2% of cases) identified in blood cultures suggest that the immediate and routine LP is of less value than expected in infants suspected to be infected. LP could be postponed when the neonate presents with a respiratory distress syndrome and/or a precarious haemodynamic state.

Bacterial Infections↗

Homogeneity of the major outer membrane protein gene of feline Chlamydia psittaci.

Thirteen feline Chlamydia psittaci strains isolated in various countries over a 50-year period were examined by restriction mapping of the major outer membrane protein (MOMP) gene obtained after DNA amplification by the polymerase chain reaction and compared with avian, ovine and guinea pig inclusion conjunctivitis (GPIC) C psittaci strains. All the feline isolates produced a unique AluI pattern distinct from the other C psittaci strains and were characterised by a typical fragment doublet of 185/180 base pairs. Such a homogeneity argues for their genetic relatedness and suggests their clonal origin. These data demonstrate the usefulness of MOMP-gene restriction mapping in C psittaci typing.

Animals↗

[Clinical value of studying hematuria using phase-contrast microscopy].

To evaluate the examination of urine erythrocytes with a contrast phase microscope for the etiological diagnosis of haematuria (erythrocytes > 10/mm3 of non centrifuged urine) the charts of 84 patients with haematuria were reviewed. A nephrological origin had been established with certainty in 56 cases with a renal biopsy and an urological origin was also established with certainty in 28 cases thanks to appropriate radiological, endoscopical and pathological examinations. The morphological criteria of the erythrocytes deformation were those of Birch and Fairley but the quantitative criteria of these authors (either 80 or 100%) were found to be of no value. By successive approaches the threshold of 20% of deformed erythrocytes was selected and found to be the best criterion for diagnosing glomerular hematuria: the sensitivity of the test is then 73% and its specificity 60%. As these results were relatively modest, conditions which decrease the percentage of deformed erythrocytes were excluded to improve the sensitivity, such as macroscopic haematuria and also examinations made during the 6 hours following furosemide administration whereas conditions which increase the percentage of deformed erythrocytes and which are easily diagnosed such as urinary infections, lithiasis and renal insufficiency associated with an uropathy were excluded in order to improve the specificity. Then the examination has a sensitivity and a specificity of 90% which makes it clinically relevant, authorizing a wait and see attitude in case there is an isolated microscopic haematuria of glomerular type.

Diagnosis, Differential↗

[Pneumopathies caused by Chlamydia pneumoniae].

Among the atypical pneumonias observed between March 1990 and March 1991, 6 were diagnosed as being caused by Chlamydia pneumoniae of the TWAR strain. The serological diagnosis was obtained by a microimmunofluorescence test. All 6 patients had anti-TWAR antibody levels higher than 512; they were treated with a macrolide administered by the oral route and were cured without sequelae or recurrences. Four cases received a ten day course of roxithromycin 300 mg/day and one case received erythromycin 2 g/day also for 10 days. The sixth case received a short course of azithromycin 500 mg once daily for three days. In 2 other patients presenting with clinical and radiological signs of pneumonia the diagnosis of C. pneumoniae infection could not be made despite an antibody level equal or higher than 512, since the serological results showed cross-reactions between C. pneumoniae, C. trachomatis and C. psittaci antibody responses.

Aged↗