Tuberculosis is a re-emerging infectious disease that causes high morbidity and mortality worldwide and remains a major health threat in many parts of the world. With the increase in the incidence of HIV-positive/AIDS patients and immunocompromised individuals, accurate and timely diagnosis of latent TB (LTB) and active TB (ATB) has gained great importance. The aim of this study was to investigate the rationale lying behind interferon gamma release assay (IGRA) requests for patients applying to various clinics of a tertiary care hospital. In the study, 2905 IGRA tests requested in two years period were analyzed retrospectively. The IGRA test positivity rates were recorded and analyzed by linking with the requesting departments and indications. IGRA test positivity was determined in 503 cases (17.31%). IGRA test positivity rates were above 20% in samples sent from general surgery, pulmonology, nephrology, and transplantation departments, respectively. At all, 54.17% of the cases from whom IGRA requests were made constituted the first group of "pre-treatment investigation", and the positivity rate in this group was 12.96%. The positivity rate was highest [163 (28.69%)] in the patient group from whom the test was requested with the suspicion of TB. As a conclusion, until today, there is no study in which IGRA test requests are evaluated in terms of clinics. In this respect, this study is thought to be important. It is also desired to highlight that it is important for each country to develop its specific guidelines, country specific indications for IGRA test requests. Multi-centered studies are also essential for a global suggestion.