Application of cetylpyridinium chloride and sodium chloride decontamination method for recovery of Mycobacterium tuberculosis from clinically suspected cases of pulmonary tuberculosis

The study was designed to compare the efficacy of cetylpyridinium chloride (CPC) and sodium chloride (NaCl) decontamination method with N-acetyl L-Cystine (NALC) and sodium hydroxide (NaOH) decontamination (the reference method) method for the recovery of Mycobacterium tuberculosis (MTB) from clinically suspected cases of pulmonary tuberculosis. To evaluate CPC-NaCl and NALC-NaOH decontamination methods, sputum specimens (n = 796) were studied (culturing on Löwenstein-Jensen medium), and the performances were compared. The CPC-NaCl decontamination method demonstrated a sensitivity, specificity, negative predictive value, and positive predictive value of 97.99%, 87.53%, 70.19%, and 99.32%, respectively, when compared to NALC-NaOH decontamination method. In summary, CPC-NaCl decontamination method effectively detected significantly higher number of MTB cases (n = 208) than NALC-NaOH decontamination method (n = 149) particularly in sputum with scanty bacilli and smear-negative cases, indicating the potential of CPC-NaCl decontamination method to preserve paucibacillary cases more efficient than NALC-NaOH decontamination method.