[Prevalence of genetic prothrombotic factors (factor V Leiden and II20210 prothrombin mutation) in glomerular nephropathies with or without thrombosis].

The presence of genetic prothrombotic factors (factor V Leiden and the prothrombin II20210 mutation) was investigated in 38 patients with glomerulonephritis with or without a history of thrombotic events and/or nephrotic syndrome. We found an increased prevalence (36%) of heterozygous factor V Leiden in those patients with a history of thrombotic events. This is ten times the prevalence in the normal Spanish population. Carrier status for this mutation may be a determining factor in the development of thrombotic events along with the acquired disorders of coagulation to which these patients are prone. We found only one patient who was a carrier of the G-A II20210 mutation of the prothrombin gene; this patient had no history of venous thrombosis or embolism. Our findings suggest the need to measure activated protein C resistance and to look for the most frequent genotype causing it, Factor V Leiden, in patients with glomerulonephritis to identify those at risk who may benefit from prophylaxis against thrombosis.