Comprehensive diagnostic approach and real-life treatment strategy in a Vietnamese pedigree with familial protein S deficiency

Abstract

Protein S is a glycoprotein essential in the regulation of blood coagulation. Familial protein S deficiency increases the risk of venous thromboembolism approximately 2- to 11-fold. Herein, we report this disorder in six members of a Vietnamese family among which three had thromboembolism, and the other three were asymptomatic. The protein S levels ranged from 10.1% to 24%, but we did not identify any PROS1 mutation. In one patient, a rare combination of protein C and S deficiency withPROC heterozygous c.565C>T (p.Arg189Trp) mutation was confirmed. Direct oral coagulation was predominantly selected for both treatment and prophylaxis, which yielded no thromboembolic and hemorrhagic events during long-term follow-up. The patients without overt clinical manifestations and those with minimized risk factors could be safely left untreated. The present family pedigree systematically illustrated a diagnostic approach and an integrated consideration for deploying various individualized treatment options.