Hyperhomocysteinemia in patients with Crohn's disease

Thromboembolic complications have been reported in patients with Crohn's disease. Among the contributing factors, hyperhomocysteinemia has been described, although controversial data exist. The aim of our study was to assess the incidence of hyperhomocysteinemia in a nonselected group of patients with Crohn's disease and to determine whether it might represent a risk marker for thrombosis in such patients.

Fifty consecutive patients were recruited, and clinical and laboratory variables were compared between those without and those with hyperhomocysteinemia. In the latter, gene mutations in N5-N10-methyltetrahydrofolate reductase were searched for, and clinical and laboratory variables were related to hyperhomocysteinemia. The presence/absence of thrombotic episodes in both groups was determined.

Both groups had similar clinically active disease, with higher C-reactive protein values found in those with hyperhomocysteinemia. Hyperhomocysteinemia was found in 46 % of patients. Of these, 74 % had moderate, 13 % intermediate, and 13 % severe increase in serum homocysteine levels. No relationship was found between homocysteine levels, and age, vitamin B12 levels, folic acid levels, Crohn's Disease Activity Index score, and CRP values. Gene mutations were found in 5 (22 %) patients, 2 homozygotes and 3 heterozygotes. None of the patients with or without hyperhomocysteinemia had episodes of venous or arterial thrombosis, or stroke.

Hyperhomocysteinemia is frequent in patients with Crohn's disease, and it could be a cofactor for the pathogenesis of thrombotic episodes.