A study to find the utility of ZN staining in the diagnosis of confirmed cases of bone tuberculosis

Introduction: As per the WHO guidelines, confirmed and definitive microbiological diagnosis of OATB is required before initiation of anti TB treatment. A study was conducted to find the utility of ZN staining in the diagnosis of confirmed cases of OATB cases. Materials and Methods: Study was conducted in the Department of Microbiology, GSL Medical College. Informed written consent was taken from all the volunteers. The study protocol was approved by the institutional ethics committee. Individuals aged > 18 years who were clinically confirmed to be OATB were included in the study. Individuals with acute pyogenic osteoarticular infections were excluded. A simple FNAC technique was conducted in the outpatient unit for the collection of aspiration. Smears were prepared and stained by Ziehl Neelsen staining. Smear preparation and staining were done as per the RNTC guidelines. Results: During the study period 38 participants with suspected OATB were included. The smear positivity was 23 (60.5%). The male-female ratio was 1.08; statistically there was no significant difference (P = 0.753954). Age-wise maximum smear-positive cases were diagnosed in 58-67 years age group. Conclusion: In resource-limited areas, ZN staining is a good alternative for the diagnosis of OATB.