B. de Barbeyrac

Genital Chlamydia trachomatis infections

Chlamydia trachomatis infections affect young, sexually active persons. Risk factors include multiple partners and failure to use condoms. The incidence of infection has increased in the past 10 years. Untreated C. trachomatis infections are responsible for a large proportion of salpingitis, ectopic pregnancy, infertility and, to a lesser extent, epididymitis. Screening is a possible intervention to control the infection, which is often asymptomatic. The emergence of lymphogranuloma venereum proctitis in men who have sex with men, in Europe, and of a variant with a deletion in the cryptic plasmid, in Sweden, are new features of C. trachomatis infections in the last years. A diagnosis is best made by using nucleic acid amplification tests, because they perform well and do not require invasive procedures for specimen collection. Single-dose therapy has been a significant development for treatment of an uncomplicated infection of the patient and his or her sexual partner.

Activity of moxifloxacin against the urogenital mycoplasmas Ureaplasma spp., Mycoplasma hominis and Mycoplasma genitalium and Chlamydia trachomatis

The activity of moxifloxacin was compared with that of other antimicrobial agents against 54 strains of Ureaplasma spp., 54 strains of Mycoplasma hominis, 14 strains of Mycoplasma genitalium, and 44 strains of Chlamydia trachomatis. Moxifloxacin inhibited 90% of all isolates at a concentration </=1 mg/L, being the most active compound against C. trachomatis and sharing the highest activity with garenoxacin and gemifloxacin against mycoplasmas. Moxifloxacin killed the 30 mycoplasma isolates tested at a concentration </=1 mg/L, except those resistant to fluoroquinolone. Thus, moxifloxacin has attracted interest as a potential therapy for mycoplasmal or chlamydial urogenital infections.

Evaluation of the Amplicor Chlamydia trachomatis test versus culture in genital samples in various prevalence populations.

OBJECTIVE--To evaluate a newly developed polymerase chain reaction (PCR) assay, Amplicor C trachomatis for the detection of C trachomatis in genital samples using cell culture for comparison. SUBJECTS--501 patients (431 women and 70 men) attending an STD clinic in Hôpital Pellegrin (high-risk population) and gynaecological clinics (low-risk population) in Bordeaux, France. METHODS--The genital samples (cervical and urethral) were tested for the presence of C trachomatis using the Amplicor test and using standard cell culture identified by the immunofluorescence test using a monoclonal antibody to C trachomatis. Discrepancies between the results of culture and Amplicor were further analysed by major outer membrane protein gene (omp1)-PCR of the specimens taken in transport media and by direct fluorescent antibody (DFA) staining of elementary bodies in culture transport tubes. RESULTS--After analysis of discrepancies, the revised sensitivity and specificity of PCR were 95.3% and 100% and the positive and negative predictive values were 100% and 99.5%, respectively. CONCLUSION--The present results indicate that the Amplicor assay is rapid, specific and more sensitive than the culture method. This test provides an excellent non-culture method for the detection of C trachomatis in various prevalence populations.

First case of Chlamydia trachomatis L2b proctitis in a woman

Since 2003, outbreaks of lymphogranuloma venereum (LGV) have been reported in European countries, North America, and Australia. Current LGV cases have been caused by Chlamydia trachomatis serovar L2. This sexually transmitted infection is predominantly found among men who have sex with men, specifically men who are seropositive for human immunodeficiency virus and have clinical signs of proctitis. The current outbreak has been almost exclusively attributed to a new variant, designated L2b. Although urogenital cases of LGV have been described in the heterosexual population, we report the first case of C. trachomatis L2b proctitis in a woman.

Rectal lymphogranuloma venereum surveillance in France 2004-2005

Lymphogranuloma venereum (LGV) is a sexually transmitted infection (STI) caused by Chlamydia trachomatis strains belonging to the L1, L2 or L3 genotype. An alert about an outbreak of LGV among MSM in the Netherlands was published in January 2004. The first cases of rectal LGV in France were retrospectively diagnosed in March 2004 and sentinel surveillance for LGV was implemented in April 2004. Most of the participating centres were located in the cities of Paris and Bordeaux. Only confirmed rectal LGV cases were included in the surveillance. Rectal specimens from men that were found to be positive for C trachomatis by PCR were sent to the National Reference Centre for Chlamydia infection for genotyping. Simple epidemiological data provided by clinicians and genotyping results were sent to the Institut de Veille Sanitaire (InVS) where data were anonymously recorded. A total of 328 C. trachomatis rectal strains isolated in men were genotyped by the end of December 2005. Of these, 244 (74%) were LGV strains belonging to the L2 genotype. No L1 or L3 C. trachomatis genotype was found. Diagnosis was made retrospectively for 46 cases. The median age of patients with LGV was 39 years. HIV status was known for 96 patients: 82/96 (85%) were HIV-infected. Most LGV cases were diagnosed in the Paris area (92%). Among the remaining 26% C. trachomatis strains, genotypes Da and G were the most frequent. As with syphilis in recent years, the emergence of LGV in Europe is mainly affecting HIV-infected MSM. The screening and treatment of STIs should be included in the clinical follow-up of all HIV-infected MSM.

Antibiotic susceptibility testing for Chlamydia trachomatis using flow cytometry

The aim of this study was to compare the effectiveness of two methods of antibiotic susceptibility testing performed on Chlamydia trachomatis-infected cells: a flow cytometric detection method and the standard method, which consists of a microscopic reading of minimal inhibitory concentration (MIC). The L2 reference strain and 13 clinical strains isolated from six patients presenting recurrent infections were tested. McCoy cells infected with an inoculum of 10(5) inclusion forming units (IFU)/ml were incubated with serial dilutions of doxycycline, ofloxacin, and erythromycin. Mean fluorescence intensity (MFI) of cells was determined by flow cytometry after staining of chlamydial inclusions with an anti-Chlamydia fluorescent monoclonal antibody. The end-point values determined by flow cytometry and microscopic reading were equivalent but presented the same imprecision. Calculation of the inhibitory concentration 50 (IC50) by flow cytometry, defined as the antibiotic concentration required to reduce the drug-free control MFI by 50%, allowed a more objective and precise evaluation of antibiotic activity than MIC. Moreover, IC50 values were reproducible, independent of the antibiotic dilution series tested, and could be used to compare the in vitro efficiency of various drugs on C. trachomatis. No resistant strain was found among the 13 clinical isolates of C. trachomatis tested.

Outbreak of psittacosis in a group of women exposed to Chlamydia psittaci-infected chickens.

Eight cases of psittacosis due to Chlamydia psittaci were identified in May 2013 among 15 individuals involved in chicken gutting activities on a mixed poultry farm in France. All cases were women between 42 and 67 years-old. Cases were diagnosed by serology and PCR of respiratory samples. Appropriate treatment was immediately administered to the eight hospitalised individuals after exposure to birds had been discovered. In the chicken flocks, mainly C. gallinacea was detected, a new member of the family Chlamydiaceae, whereas the ducks were found to harbour predominantly C. psittaci, the classical agent of psittacosis. In addition, C. psittaci was found in the same flock as the chickens that the patients had slaughtered. Both human and C. psittaci-positive avian samples carried the same ompA genotype E/B of C. psittaci, which is widespread among French duck flocks. Repeated grassland rotations between duck and chicken flocks on the farm may explain the presence of C. psittaci in the chickens. Inspection by the veterinary service led to temporary closure of the farm. All birds had to be euthanised on site as no slaughterhouses accepted processing them. Farm buildings and grasslands were cleaned and/or disinfected before the introduction of new poultry birds.

Reactive arthritis associated with L2b lymphogranuloma venereum proctitis

An ongoing outbreak of lymphogranuloma venereum (LGV) L2b proctitis, predominantly in HIV-positive men who have sex with men (MSM), has been reported in industrialised countries. A case of reactive arthritis after L2b proctitis is described. This case expands the spectrum of severe complications related to LGV L2b proctitis. Since this infection may be asymptomatic, this organism should be screened for in HIV-positive MSM with symptoms consistent with reactive arthritis.

Primary liver abscess due to CC23-K1 virulent clone of Klebsiella pneumoniae in France

Since the mid-1980s, Klebsiella pneumoniae hypermucoviscous isolates have emerged in Taiwan and other Asian countries. We reported the first autochthonous European liver abscess due to an ST57 isolate, which belongs to virulent clonal complex CC23-K1. This case highlights the emergence in France and Europe of hypermucoviscous virulent K. pneumoniae isolates.

Evaluation of the combination of the NucliSENS easyMAG® and the EasyQ® applications for the detection of Mycoplasma pneumoniae and Chlamydia pneumoniae in respiratory tract specimens

Mycoplasma pneumoniae and Chlamydia pneumoniae are respiratory tract pathogens frequently involved in community-acquired pneumonia, but are fastidious microorganisms. Their direct detection mainly requires molecular amplification techniques. A nucleic acid extraction system, NucliSENS easyMAG®, and a real-time nucleic acid sequence-based amplification (NASBA) technique, NucliSENS EasyQ®, were recently developed by bioMérieux to detect both bacteria. The aim of our study was to compare the easyMAG/EasyQ combination with our in-house combination, MagNA Pure extraction (Roche) and real-time polymerase chain reaction (PCR), to detect both bacteria in respiratory tract specimens. The analytical specificities of both combinations were similar. A higher analytical sensitivity was found for C. pneumoniae using the easyMAG/EasyQ combination, since the easyMAG/EasyQ system detected nucleic acid extracts 106 times more diluted than the in-house combination. Both combinations were equivalent when detecting M. pneumoniae in positive respiratory tract samples. Finally, the easyMAG/EasyQ combination is a potential useful tool for the detection of both bacteria regarding sensitivity, specificity, monitoring, and standardization of the procedure.