Authors : Prasanna Nakate, Snehal Patil, Suvarna Patil, Heetendrakumar Purohit, Yogendra Shelke
DOI : 10.18231/j.ijmmtd.2019.050
Volume : 5
Issue : 4
Year : 2019
Page No : 218-221
Introduction: Tuberculosis (TB) is a highly communicable disease and a major health problem in many
countries. An early diagnosis and treatment is important for controlling its spread. Conventional methods
for TB diagnosis such as microscopy have low sensitivity. Though culture is considered as gold standard,
it is time consuming. Newer molecular diagnostic methods such as GeneXpert assay are rapid and highly
sensitive and are now playing a pivotal role in TB diagnosis.
Materials and Methods: In the present study, we compared the diagnostic efficacy of Ziehl Neelsen (ZN)
staining & microscopy with GeneXpert assay for diagnosis of pulmonary tuberculosis in case of 660
patients of suspected pulmonary TB.
Results: In this study, a total of 660 sputum samples were tested by both Z-N staining and microscopy and
by GeneXpert assay. Of these, 23.73% of sputum samples were tested positive for acid fast bacilli (AFB) by
smear and microscopic examination while 72.27% were negative for AFB. When the same sputum samples
were subjected to GeneXpert assay, 34.24% samples were tested positive indicating higher sensitivity for
detection of TB bacilli. 65.76% samples gave negative result in GeneXpert.
Conclusion: This study indicates that GeneXpert assay is more sensitive for detection of TB bacilli in
sputum samples as compared to smear and microscopy alone. It should be considered as an effective tool
for early diagnosis of tuberculosis especially in countries where it is prevalent.
Keywords: Tuberculosis Z-N staining, M. tuberculosis, GeneXpert assay, Pulmonary TB.