Effectiveness Comparison of Decontamination Sputum Specimen between Kudoh and Petroff Modification Technique in Mycobacterium Culture

Objectives: Tuberculosis (TB) is the common cause of death due to a single infectious agent. MTB culture is still the gold standard for TB diagnosis. For optimal care of pulmonary TB, effective decontamination methods are required to isolate and identify MTB. The simpler Kudoh decontamination/culture method swab was compared with modified Petroff to isolate mycobacteria from sputum specimens. Materials and Methods: A total of 15 sputum samples were collected from patients with Xpert MTB/RIF assay-confirmed pulmonary TB. The samples were processed with both decontamination methods. Each sample group was inoculated directly on the Lowenstein-Jensen (LJ) and the Middlebrook 7H10 agar medium. The growth of contamination, recovery rate, and detection time were observed in both media. Results: Out of 15 samples, the contamination rate on the LJ by both methods was 2 (13%), respectively, whereas the Middlebrook 7H10 by both methods showed 1 (6.6%). The recovery rate on the LJ was 13 (86.6%) by the Kudoh method and 14 (93.3%) by the modified Petroff method, while 13 (86.6%) showed positive culture on the Middlebrook 7H10 by both. In this study, positive culture results using the modified Petroff technique showed more colony growth than the Kudoh technique, indicating more viable MTB colonies than the Kudoh technique. Conclusion: Petroff modification technique shows the growth of the number of colonies more than Kudoh technique, but the Kudoh technique shows the results of positive culture that is no different to the recovery level even though the number of colonies that grow in less Kudoh technique.