Analysis of the changes in bacterial types and drug sensitivity profiles of mycobacterial strains in Guangzhou over the last twelve years / 中华预防医学杂志

<p><b>OBJECTIVE</b>To improve evidence-based care in the management of tuberculosis, we retrospectively analyzed the bacterial types and drug sensitivity test results of mycobacteria in Guangzhou over the past twelve years (from July 1998 to March 2010).</p><p><b>METHODS</b>Over these twelve years, a total of 14 095 mycobacterial strains isolated from different samples were subjected to type identification and drug sensitivity tests according to the Standard Protocols of Laboratory Diagnostics for Tuberculosis by the Chinese Antituberculosis Association. Chi-square test was performed for statistical analyses for comparisons between groups.</p><p><b>RESULTS</b>Of 14 095 strains of mycobacteria isolated, 10 844 strains (76.84%) were MTB, and 3251 strains (23.16%) were non-tuberculosis mycobacteria (NTM). Compared with the result of the fourth national survey of tuberculosis epidemiology, which showed 11.1% of NTM, the one of our study was significantly different (χ(2) = 69.79, P < 0.001). Drug sensitivity tests of MTB showed tolerance rates of 28.99% (2729/9413), 21.75% (2047/9413), 17.45% (1643/9413) and 11.53% (1085/9413) against isoniazid, rifampin, streptomycin and ethambutol, respectively.</p><p><b>CONCLUSION</b>An increasing trend was observed in MTB drug tolerance against streptomycin, rifampin and isoniazid, whereas more and more NTM strains were isolated in recent years. These findings are worthy of note for clinicians.</p>

To investigate the clinical diagnostic value of four mycobacteria tuberculosis detection methods / 中华检验医学杂志

Objective To evaluate the clinical diagnostic value of nucleic acid amplification (TB- RNA),bacteriophage-based assay,3D culture and smear on the detection of Mycobacteria tuberculosis.Methods 291 clinical sample including 110 sputum,54 thoracic fluid,37 throat swab,31 bronchial fluid,13 cerebrospinal fluid,12 urine,8 lymph fluid and 20 others (pericardial effusion,feces, blood and abdominal fluid) and gynecological specimen (including 6 leucorrhoea and menstrual blood) were analyzed by these four methods.Results Among the 291 clinical samples,the positive rate of mycobacteria tuberculosis for TB-RNA,bacteriophage-based assay,3D culture and smear were 37.1%,28.9%,27.5% and 10.3%.The sensitivity and specificity of the TB-RNA,bacteriophage-based assay,3D culture and smear were 54.3% & 100%,41.7% & 88.9%,31.7% & 93.5% and 14.6% & 98.9%,respectively.Conclusions TB-RNA is an effective clinical diagnostic method for Mycobacteria tuberculosis.Although the sensitivity of smear is poorer than others,it is a universal testing method in clinical laboratory due to low cost.The positive rate of mycobacteria tuberculosis for 3D culture is lower than that of bacteriophage-based assay and TB-RNA.Although the time to result for 3D culture might last for few weeks,the isolates can be used for drug resistance screening and bacterial identification.