Heterozygosity for homocysteinuria: a detectable and reversible risk factor for pulmonary thromboembolism

Heterozygosity for homocysteinuria is a common, inherited autosomal condition that has recently been considered as an independent cardiovascular risk factor. In vitro and in vivo results suggest that this condition, like the homozygous form, is also a risk factor for deep-venous thrombosis and pulmonary thromboembolism. We report a case of recurrent pulmonary thromboembolism in a young woman with familial hyperhomocysteinaemia. The relative frequency of this condition, as well as its simple and harmless cure, make testing for heterozygosity for homocysteinuria useful and profitable in the prevention of pulmonary thromboembolism, above all in younger subjects with a significant case history.