SYMPTOMATIC VERSUS ASYMPTOMATIC PATIENTS IN CONGENITAL HYPOPLASMINOGENEMIA - A STATISTICAL-ANALYSIS

In the present study, the prevalence of thromboembolic events in patie nts suffering from type I plasminogen deficiency was evaluated. One hu ndred and twelve affected subjects belonging to twenty-eight kindreds were gathered from the literature and from personal observations. The incidence of thrombosis found in this group was compared with those se en in: a) 86 unaffected family members; b) 100 hospitalized patients; c) 100 outpatient clinic patients. In the latter two groups, congenita l clotting disorders were excluded. Thrombotic manifestations were fou nd in 25.8% of patients with plasminogen deficiency, a figure which wa s statistically different from those found in unaffected family member s (1.16%, p < 0.001), hospitalized patients (3%, p < 0.001) and outpat ient clinic patients (5%, p < 0.001). In twenty-four kindreds with hyp oplasminogenemia, data concerning the actuarial ages at first thrombot ic event were available for construction of thrombosis-free survival c urves by the Cutler-Ederer method. The difference between the two curv es, corresponding to affected and unaffected family members respective ly, were statistically significant (p < 0.01). In conclusion, although the incidence of thromboembolic events in type I plasminogen deficien cy is certainly lower than that described in other congenital clotting disorders such as AT III, protein C and protein S, patients with hypo plasminogenemia should be considered at risk for thrombosis, particula rly when triggering factors are present.