Comparison of N-Acetyl-L-Cysteine and Sulfuric Acid Decontamination Methods For Recovery of Mycobacteria |
The most frequently isolated NTM were Mycobacteriumlentiflavum and Mycobacterium intracellulare. Comparing the two decontaminationmethods the recovery of NTM in the sulfuric acid group was significant higherthan in the NaOH-NALC group (p=0.001).In contrast, no significant difference was found for the recovery. Theseresults show that the decontamination method used affects the recovery ofnontuberculous mycobacteria in particular. These considerations have promptedus to compare the effect of these two decontamination procedures on thesensitivity of the detection of M. tuberculosis complex and NTM in sputum samples. The study was carried out intwo rural hospitals HIV prevalence was approximately 20%. In the present studywe found a high rate of positive cultures for mycobacteria. Of the 261 isolatespositive for mycobacteria 62 (24%) were identified as M. tuberculosis and 139(53%) were identified as NTM. Significantly more NTM were recovered by thesulfuric acid decontamination method than by the NaOH-NALC method (84 versus 55respectively). There was no significant difference between the sulfuric aciddecontamination method and the NaOH-NALC method.