Significance of a Family-based Study of Hereditary Thrombosis: A Single-family Case Series of Protein C Deficiency

Abstract

Thrombophilia is a serious unpredictable complication caused by gene mutations, resulting in anticoagulant deficiencies. We herein report a single-family case series of protein C (PC) deficiency. Case 1 involved a Japanese man whose PC deficiency resulted in severe systemic thrombosis. The patients in cases 2 and 3 were his daughters who were diagnosed with PC deficiency via carrier screening in 2001 and later both became pregnant. Owing to appropriate treatments during pregnancy, they did not develop thrombosis and safely gave birth to healthy infants. This family case series suggests that appropriate knowledge concerning thrombophilia helps prevent future emergencies.

Keywords: hereditary thrombophilia; protein C deficiency; single family.

Figure 1.

The family pedigree and coagulation profiles in 2001. The arrow indicates the proband. The half-solid boxes represent the men (squares) and women (circles) with heterozygous protein C deficiency. †: deceased, ANA: antinuclear antibody, C-Ag: protein C antigen, LAC: lupus anticoagulant, Lp (a): lipoprotein (a), PAC: protein C activity, PAS: protein S activity, S-Ag: protein S antigen

Figure 2.

Photograph of the fundus of the right eye showing total occlusion of the retinal artery.

Figure 3.

Clinical course of Case 2.

Figure 4.

Clinical course of Case 3.