Autosomal-dominant inheritance of the prothrombin gene mutation in a Puerto Rican family: A case study.

Splenic infarction is rare and the prothrombin gene mutation (PGM) is not commonly observed in Puerto Rico. PGM is present in 1% of the general population, and in 7% of the people with deep venous thrombosis (DVT); it is found in up to 40% of patients with splenic-portal-mesenteric thrombosis. Our study has identified a Puerto Rican family of four generations whose members all have inherited PGM in an autosomal dominant manner. The eldest member of the family, an 82-year-old male, presented with DVT of the lower extremity. The man's 62-year-old daughter had suffered a splenic infarction; his 37-year-old grandson presented with superficial and deep vein thrombosis (SDVT), and his great-grandson of 8 years was asymptomatic at the time of the report. This is the second report of PGM as the cause of a hypercoagulable state and the first reported PGM-related splenic infarction in Puerto Rico. We need to test for genetic hypercoagulable states in the members of Puerto Rican families with thromboembolism. Once testing has revealed the existence of such states in a given family, it is important that the family members receive genetic counseling.