Comparative Evaluation of Ziehl-Neelsen and Kinyoun Staining in the Diagnosis of Clinically Suspected Cases of Pulmonary Tuberculosis

Abstract

Background: Bacteriological examination of sputum is the cornerstone in diagnosis of pulmonary tuberculosis in developing world, which is usually done using a Ziehl-Nelseen (ZN) method. However, due to limited laboratory facilities that can satisfy the procedure, applicability of this procedure appears to be adversely affected in field conditions and at peripheral health institutions. Hence, it has become necessary to look for a procedure which can be used as alternative in such conditions. Material and Methods: This was a cross sectional study conducted in the Department of Microbiology, Index Medical College Hospital & Research Centre, Indore, Madhya Pradesh in conjunction with the Chest TB Clinic of Index Hospital, New Delhi for a period of 1year [from February 2018 to January 2019]. Two sputum samples were collected from 100 cases of clinically suspected pulmonary tuberculosis. Total 200 sputum samples were taken. Each sample was divided in two parts. One part of the sample was decontaminated by NALC method and subjected to ZN and Kinyoun staining. Data was analyzed by using SPSS version 17.0. Results were expressed as total percentages/ proportions. Results: Out of the total hundred (n=100) cases, 67% were males and remaining 33% were females. The age of the patients ranged from 18 years to 73 years. Maximum number of cases (n=37; 37%) were in the age group 18-30 years followed by 29 cases (n=29; 29%) were in the age group 31-40 years. Most common complaints by the patients was cough (100%) followed by fever (83%), anorexia (69%), weight loss (44%), expectoration (37%) and hemoptysis (17%). Of the 100 direct smears examined 55 (55%) were positive by the cold staining methods in contrast to 62 (62%) by the conventional ZN method (Table 2). Statistically using the unpaired students 'T' test method there was no significant difference between the results of the two methods (p > 0.5). Conclusion: This study concluded that kinyoun staining has almost similar case detection rate of pulmonary tuberculosis as compared to ZN staining method. Decontamination by the NALC method increases the detection of case positivity rate of Mycobacterium tuberculosis.