The Evaluations of Bleach as Decontaminant Solution to Promote The Positivity Rate of Mycobacterium Tuberculosis Culture for Sputum Specimen

摘要

Background: Tuberculosis (TB) is still worldwide health problems. Sputum is contaminated by normal flora, that make its should be decontaminated prior to culture. Bleach known as a potent disinfectant, easy to access because it is commercially available, could be the alternative solution as decontaminant in TB culture. Aims Assessing the capability of bleach to promote the positivity rate in TB culture compared by others decontaminant solution. Method We use 35 sputum samples with volume 3-5 ml. The research was conducted at TB laboratory of Faculty of Medicine University of Indonesia, by using 35 samples sputum with positive AFB, 3-5 ml. Each sample was divided into 4 groups that were decontaminated by different methods. The methods are 4%NaOH, 2%NALC-NaOH, 5% oxalic acid and 1% bleach. 1% bleach was prepared from commercially bleach. The positive culture was validated using MPT 64. The culture positivity rate was compared based on its AFB score. Result Bleach had the same 100% positivity rate as the 4% NaOH and NALC for (+2) and (+3) AFB. However, its became smaller rate for the (+1) AFB group, which was 88% for bleach and 96% for NALC and 100% for NaOH. Oxalic acid had the smallest positivity rate in all AFB score compared to the others. Conclusion The positivity rate of the bleach as same as 4% NaOH and NALC for AFB score higher than (+2).