Comparison Of Ziehl-Neelsen and Auramine Rhodamine Staining for The Detection of Mycobacterium Tuberculosis in Sputum Samples

Abstract

Introduction: Tuberculosis is a global health problem. A rapid and accurate diagnostic technique is necessary for effective management. The primary method for detection of Mycobacterium Tuberculosis (MTB) is sputum smear microscopy, using Ziehl-Neelsen (ZN) stain which has limitations. However, Auramine Rhodamine (AR) staining provides similar specificity but increased sensitivity. This study was conducted for comparison of ZN and AR staining in the detection of Mycobacterium Tuberculosis (MTB).

Methods: This study was conducted between March to July, 2025 . Ethical approval was taken from Institutional Review Committee (Ref. No. MTH/001/2025). Written consents were taken from patients. Early morning sputum samples were collected and processed for ZN and Auramine staining. Data were analyzed using SPSS software.

Results: Out of 100 samples, 13 (13%) were positive for Mycobacterium tuberculosis. Eight of these were positives by AR staining only and 5 were positive by both ZN and AR staining. There were no cases that were negative with AR but positive with ZN method. There was no association between demographic and other factors such as age (χ²=1.705; p=0.636), sex (χ²=0.048; p=0.826), smoking (χ²=0.088; p=0.766) and diabetes (χ²=1.076; p = 0.300) with the detection of MTB. However, a significant association was observed between family history of TB (χ² =13.613; p < 0.001) and patient’s occupation (χ² = 7.696; p = 0.006).

Conclusion: Auramine rhodamine staining was found superior to ZN for the detection of MTB. Our results suggest that house hold contacts of TB and high risk groups especially farmers should be investigated on a priority basis.