INNO-LiPA Mycobacteria (LiPA; Innogenetics, Zwijnaarde, Belgium) is a kit for the simultaneous detection and identification of Mycobacterium species in culture and identifies the Mycobacterium tuberculosis complex, the M. avium complex (MAC), and the following Mycobacterium species: M. kansasii, M. avium, M. intracellulare, M. scrofulaceum, M. gordonae, M. xenopi, and the M. chelonae-M. abscessus complex. The assay, which targets the 16S-23S rRNA spacer region, was evaluated on 157 mycobacterial strains that had been identified by conventional techniques and PCR-restriction enzyme analysis of the hsp65 gene (PRA). Forty-seven reference strains consisting of 37 different species and 110 human clinical isolates were submitted to the test, and all were hybridized with the Mycobacterium genus probe (MYC) on the LiPA strip (100% sensitivity). Ninety-four isolates hybridized to their corresponding species-or complex-specific probes; only one isolate phenotypically identified as M. gordonae did not react with its specific probe (99.4% accuracy). Thirty-seven MAC strains were phenotypically identified to the complex level and to the species level by LiPA as M. avium (n ‫؍‬ 18) or M. intracellulare (n ‫؍‬ 7) or as belonging to the M. avium-M. intracellulare-M. scrofulaceum complex (n ‫؍‬ 12). Of the last 12 strains, 10 had M. avium PRA patterns and 2 had M. intracellulare PRA patterns. Three isolates that had been identified as a single species by conventional identification were proven to be mixed cultures by the LiPA assay. The whole procedure can be performed in 1 working day, starting with the supernatant of a small amount of bacterial mass that had been treated by freezing and then boiling.To date, more than 70 mycobacterial species have been identified, and occasionally, isolates with unknown characteristics, mostly from immunodeficient patients, are being described. Differentiation of pathogenic and nonpathogenic mycobacteria other than Mycobacterium tuberculosis (MOTT) from members of the M. tuberculosis complex (MTC) is needed for patient management, considering that many MOTT are resistant to the antibiotics used for treatment of tuberculosis (27).Identification of mycobacterial isolates to the species level is performed by analysis of phenotypic and biochemical characteristics of the organisms after culture in solid media, which is a time-consuming process, or by high-pressure liquid chromatography analysis, which requires expensive equipment. Development of molecular tests has speeded up diagnosis, but most methods suffer from specific drawbacks. The AccuProbe system (Gen-Probe) differentiates only the MTC, M. avium, M. intracellulare, M. gordonae, and M. kansasii. In-house PCRbased identification systems have been developed but either identify a limited number of mycobacterial species or are difficult to use on a routine basis (4, 11). Restriction enzyme analysis of PCR products of specific genes is still widely used for identification of mycobacteria to the species level (7,19,23) and on clinical isolates (...

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Tubercle bacilli may survive in unstained heat-fixed sputum smears and may be an infection risk to laboratory staff. We compared the effectiveness of 1% and 5% sodium hypochlorite, 5% phenol, 2% glutaraldehyde, and 3.7% formalin in killing Mycobacterium tuberculosis present in smears prepared from 51 sputum samples. The smears were decontaminated by the tube and slide techniques. Phenol at 5%, glutaraldehyde at 2%, and buffered formalin at 3.7% for 1 min (tube technique) or for 10 min (slide technique) were effective in decontaminating sputum smears and preserved cell morphology and quantitative acid-fast microscopy results.Direct microscopy for detection of acid-fast bacilli (AFB) in sputum specimens remains the main tool for presumptive diagnosis of pulmonary tuberculosis in many countries (3). In Brazil, 70% to 80% of all pulmonary tuberculosis cases are identified by this method (3,4,5,12,13). In health units with inadequate facilities, sputum specimens are normally collected and sent as heat-fixed smears to a reference laboratory for microscopic examination. Depending on the distance and available means of transport, analysis of the sputum smears may be delayed for days. Some studies have shown that tubercle bacilli may survive in unstained heat-fixed sputum smears for at least 7 days (1,2,6,11,14) and may therefore present a potential risk of transmission of laboratory-acquired infections (9,17,19).The use of decontamination agents such as phenol (7), formaldehyde (2, 9), sodium hypochlorite (17), and glutaraldehyde (10, 11) to kill the tubercle bacilli present in smears has been documented. Decontamination of slides with these agents has improved the biosafety in transport, storage, or manipulation of slides containing sputa from patients suspected of having pulmonary tuberculosis.The decontaminating agent should kill the tubercle bacilli present in sputum smears without impacting the quantitative acid-fast microscopic results, i.e., by altering the original characteristics of the specimen or by destroying the structure of the tubercle bacilli.We compared the effectiveness of (i) 5% phenol (Merck, Darmstadt, Germany), (ii) 3.7% buffered formalin (Miyako do Brazil Indústria e Comércio Ltda., São Paulo, Brazil), (iii) 2% glutaraldehyde (Johnson & Johnson, São Paulo, Brazil), and (iv) 1% and 5% sodium hypochlorite (Miyako) for decontaminating unstained heat-fixed smears of sputum from patients suspected of having pulmonary tuberculosis. The effects of these decontaminating agents on cell morphology and on quantitative acid-fast microscopy were also studied.Sputa. Fifty-one specimens containing high numbers (grade 3ϩ) (3) of viable Mycobacterium tuberculosis bacilli obtained from outpatients who attended a health care unit (Centro de Referência Professor Hélio Fraga, Rio de Janeiro, RJ, Brazil) were studied. The specimens were transported by air to Maringá City (Universidade Estadual de Maringá, PR, Brazil) and tested within 3 days after collection. One hundred twenty-four smears from each sample (total, 6,32...

, ; and 100% specificity for AMI (85.4-100), , and compared to the BACTEC system. Comparing the results obtained in LJ we observed 100% sensitivity for RMP , followed by , , and 100% specificity for all drugs tested except for

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Human isolates of