ABSTRACT

We aimed to evaluate the relevancy of QuantiFERON-TB Gold (QFT) test which was required for the specific aims from the various clinics of Cerrahpaşa Medical Faculty by determining the using frequency and results of the QFT test in this retrospective study.

The in vitro studies of QFT test were performed from the whole blood samples according to the manufacturer’s recommendations between January 2018 and December 2019. The numbers and results of QFT test were retrospectively determined according to the required clinics and were taken into consideration.

The test positivity was detected in 151 (12.5%) from the whole blood samples of 1,207 patients from various clinics. It was determined that the test request was made most frequently from the neurology clinic with 297 (24.6%) cases, followed by the rheumatology and infectious diseases clinics with 235 (19.5%) and 142 (11.8%), respectively. It was also determined that the most common positivity detection rate among the clinics requesting the test was from the ophthalmology clinic.

It is noteworthy that the frequency of the test request was expected to be higher in the chest diseases and infectious diseases clinics, but unexpectantly, test request frequency was rather higher in the neurology and rheumatology clinics, whereas the high positivity in the test request was observed in the ophthalmology clinic. When the QFT test was examined on the number of test requests in the clinics and the relation between positive results, it was determined that there was a discrepancy between the number of purposeful requests and the positive result obtained. Considering the effectiveness of both the cost of the commercial kit and the positive results obtained in guiding clinicians, we believe that it would be beneficial to review the test requests at the national algorithms level by clinics.

Keywords: Latent Tuberculosis Infection, Mycobacterium tuberculosis, Diagnosis, Tuberculosis