TPMTtestiä

TPMTtestiä is a Finnish term that translates to "TPMT testing" in English. TPMT refers to the enzyme thiopurine S-methyltransferase. This enzyme plays a crucial role in the metabolism of certain medications, particularly thiopurine drugs like azathioprine, mercaptopurine, and thioguanine. These drugs are commonly used in the treatment of autoimmune diseases, inflammatory conditions, and certain types of cancer.

TPMTtestiä is a pharmacogenetic test that determines an individual's activity level of the TPMT enzyme. Genetic variations can lead to individuals having very low or absent TPMT activity (poor metabolizers), intermediate activity (intermediate metabolizers), or normal activity (normal metabolizers). This variability significantly impacts how a person metabolizes thiopurine drugs.

For individuals with low TPMT activity, thiopurine drugs can accumulate to toxic levels in the body, leading to severe side effects such as bone marrow suppression, which can manifest as low white blood cell counts, red blood cell counts, and platelet counts. This can increase the risk of infections and bleeding.

Therefore, TPMTtestiä is often performed before initiating treatment with thiopurine medications. The results of the test help clinicians to personalize drug dosing. For poor metabolizers, a lower starting dose of the medication is typically recommended, with careful monitoring of blood counts. For intermediate metabolizers, a reduced dose may also be considered. For normal metabolizers, standard dosing can usually be used. This proactive approach aims to optimize treatment efficacy while minimizing the risk of serious adverse drug reactions.