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Two patients with COMT inhibitor-induced hepatic dysfunction and UGT1A9 genetic polymorphism
E Martignoni1, M Cosentino, M Ferrari
1Department of Clinical Medicine, University of Piemonte Orientale Amedeo Avogadro, Salvatore Maugeri Foundation, Scientific Institute of Veruno, Novara, Italy.
Catechol-O-methyltransferase (COMT) inhibitor use in Parkinson disease patients can cause liver issues. Specific genetic mutations in UDP-glucuronosyltransferase (UGT) 1A9 may increase the risk of this drug-induced liver injury.
Area of Science:
- Pharmacogenetics
- Hepatology
- Neurology
Background:
- Parkinson disease management often involves catechol-O-methyltransferase (COMT) inhibitors.
- Hepatotoxicity is a potential adverse effect of COMT inhibitor therapy.
- UDP-glucuronosyltransferase (UGT) 1A9 plays a key role in metabolizing COMT inhibitors.
Observation:
- Two women with Parkinson disease developed asymptomatic hepatic dysfunction during COMT inhibitor treatment.
- Genetic analysis revealed these patients carried mutations in the UGT1A9 gene.
- These mutations resulted in impaired glucuronidation activity.
Findings:
- The UGT1A9 gene encodes the primary enzyme responsible for COMT inhibitor metabolism.
- Patients with defective UGT1A9 glucuronidation activity may be susceptible to COMT inhibitor-induced liver damage.
- Poor UGT1A9 metabolizer genotypes are identified as a potential risk factor for hepatotoxicity.
Implications:
- Genetic screening for UGT1A9 polymorphisms could identify patients at higher risk for COMT inhibitor hepatotoxicity.
- This finding may guide personalized medicine approaches in Parkinson disease treatment.
- Further research is warranted to confirm the role of UGT1A9 genotype in COMT inhibitor-related liver injury.
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