First description of Mycobacterium tuberculosis and M. canettii concomitant infection: report of two cases.

We report the first two cases of tuberculous coinfection with Mycobacterium tuberculosis and M. canettii. Both patients were young Djiboutian females with pulmonary tuberculosis (TB). One had a miliary pattern with concomitant human immunodeficiency virus infection. Both recovered completely with a standard four-drug anti-tuberculosis treatment regimen. Due to the different natural reservoirs and routes of infection of these two strains, our study supports the common belief that multiple strains of infection in TB are related to superinfection rather than concomitant infection.

[Performances of the Amplified Mycobacterium Tuberculosis Direct Test in non respiratory specimens (study about 1538 samples)]. / Performances du test "Amplified Mycobacterium Tuberculosis Direct Test" sur les échantillons extrarespiratoires (étude sur 1538 échantillons).

From March 1998 to August 2009, 1538 non-respiratory samples collected from 1182 patients, were tested using the Gen-Probe Amplified Mycobacterium Direct Test™ (AMTD). After decontamination procedure, every sample was tested by AMTD and by culture on solid and liquid media. The "Gold-standard" was considered by the combination of culture results and clinical diagnosis. Tuberculosis was present in 17,59 % (208 patients). For theses 1538 non-respiratory samples (225 culture positive samples, 248 AMTD positive), 279 corresponded to tuberculosis. After resolving the discordant results, the sensitivity, specificity, positive and negative values were 89, 99, 99,6 and 97,3 %.

[Evaluation of the SD BIOLINE TB Ag MPT64 Rapid® for the diagnosis of tuberculosis]. / Évaluation du kit SD BIOLINE TB Ag MPT64 Rapid® dans le cadre du diagnostic de la tuberculose.

The purpose of this study was to evaluate the SD Bioline Ag MPT64 Rapid(®) for identification of the Mycobacterium tuberculosis complex. The method uses an immunochromatographic assay and needs 100 µl of sample taken from liquid culture or colonies suspended. The sensitivity was determined using 99 strains of M. tuberculosis complex and the specificity using 10 nontuberculous mycobacteria and 85 strains other than mycobacteria genus. The test showed excellent sensitivity (99%) and specificity (100%). This technique displays several advantages and is destined to spread in all laboratories and particularly in endemic areas.

[Performances of the assay MTBDRplus(®) in the surveillance of rifampicin resistance in Mycobacterium tuberculosis]. / Performances du kit MTBDRplus(®) dans le cadre de la surveillance de la résistance à la rifampicine chez Mycobacterium tuberculosis.

The purpose of the survey was the routine assessment of the MTBDRplus(®) kit performance in the determination and characterization of Mycobacterium tuberculosis resistance to rifampicin. The survey was carried out on a collection of 144 strains (126 of which were resistant to rifampicin) isolated on patients from 15 countries. Sensitivity to antituberculosis drugs was determined by a liquid culture system and the reference method was the amplification and sequencing of a target region of the rpoB gene whose mutations are responsible for rifampicin resistance (codons 507 to 533). The assessed kit was based on a reverse hybridization technique using eight overlapping probes covering the target region and four probes representing the most-frequently observed mutations. The assay performance was found excellent, specificity: 100%, sensitivity: 99.2%; 17 mutations affecting 10 codons were reported, two of which were newly identified.

[Assessment of the Patho-TB kit for diagnosis of tuberculosis]. / Evaluation du kit Patho-TB dans le cadre du diagnostic de la tuberculose.

Where tuberculosis is concerned, early diagnosis, especially for active pulmonary cases, allows to quickly start therapy. We evaluated the Patho-TB kit (Anda Biologicals, France) as an alternative for the fastidious search for acid-fast bacilli by the Ziehl-Neelsen method. Three hundred and ten samples from 189 patients were collected between July 2005 and March 2006, these were divide between 301 pulmonary and 9 extrapulmonary samples. The Patho-TB tests consists of a filtration step on a cassette followed by an immuno-chromatographic revelation. Samples were decontaminated by the Kubica method; after neutralization, an aliquot of the centrifuged pellet was saparated for evaluation of the Patho-TB test. The rest was used for direct microscopic examination and cultures on solid and liquid medium. Positive results with auramine were always confirmed by the ZN staining. Analysis of the results per sample gave the follows results: 91.1% sensitivity and 85.5% specificity compared to 91.8% and 100% respectively or microscopy. Sensitivity of the Patho-TB test rose to 93.7% when only the MTB complex was considered. Per patient, the Patho-TB was found to be 96.4% sensitive and 86% specific. By comparison the sensitivity of microscopy was 94.5% and its specificity 100%. Positive and negative values were respectively 90.6% and 94.4% for the Patho-TB while they were 100% and 92.9% for microscopy. It is concluded that the Patho-TB test gives good performances; it is easy to use and very easy to determine the results. For direct observation, we recommend this test to laboratories that do not perform microscopy with auramine, which is the case in tuberculosis endemic areas.

A theoretical investigation of the pressure and temperature dependence of atmospheric ozone deposition to trees.

Methods for describing the exposure patterns of forests to atmospheric ozone concentrations are compared with special emphasis on the situation at high altitudes, such as the Appalachian Mountains of the eastern USA. Limitations to the use of ozone concentration as mass per unit volume are discussed and a correction for temperature and pressure changes is derived. If identical ozone mass concentrations were measured at two sites separated by 2000 m elevation, the ozone flux at the lower site would exceed the flux at the higher site by 4-8% due to temperature and pressure effects on both air volume and ozone deposition velocity. It is recommended that ozone exposures be described in terms of 'flux-corrected' mass concentrations or volumetric mixing ratios when ambient ozone data from sites at different altitudes are to be compared.