Analytical Interference with Contrast Agents in Genetic Test Result for Thrombophilia

Abstract

Background: Diagnostic and therapeutic drugs can change the laboratory results of patients by interfering with the measurement method and may compromise diagnostic efficiency. Incorrect results in biochemical tests used in the clinical follow-up of a patient during treatment may lead to improper applications. Unfortunately, this situation leads the clinician to misdiagnosis. Objective: The focus of this cross-sectional study is to investigate the effects of three different radiopaque substances commonly used in the clinic on thrombophilia molecular genetic results. Methods: Peripheric blood samples from three patients whose thrombophilia panel was planned to be studied were included. Blood samples that did not contain any radiopaque material or distilled water were studied as a control group. Except for the control group four different study groups were formed by adding distilled water, Ioversol, Fluorescein Na, and Gadobutrol. This radiopaque substances were added at a ratio of 1/10 to each patient's blood sample before DNA isolation. Prothrombin G20210A, MTHFR C677T, MTHFR A1298C, Factor V Leiden G169A and PAI-1 4G/5G mutations were studied by Real Time-PCR method. Results: There was no change at the thrombophilia panel results in the study groups compared with the control groups in patients 1 and 3. In patient 2, there was no change when the result of MTHFR C677T was compared to the results of blood+DW and blood+Gadobutrol. But there were alterations in blood+Ioversol and blood+Fluorescein Na samples; the result of heterozygous MTHFR C677T was observed to change to homozygous MTHFR C677T. Conclusion: This study showed that Ioversol and Fluorescein Na could change the results of the thrombophilia genetic analysis for MTHFR C677T mutation. It should be kept in mind that the results of the thrombophilia panel analysis may change after the injection of radiopaque substances.