Incidence of and risk factors for childhood thrombosis: a single-center experience in Ankara, Turkey.

This study was conducted to analyze the incidence of and risk for thrombosis in thrombotic children monitored in the Department of Pediatric Hematology of our hospital at the time of diagnosis, in addition to the clinical characteristics of those patients. The clinical and laboratory findings of 122 patients diagnosed with thrombosis from 1997 to 2006 were retrospectively analyzed. The incidence of thrombosis was 88.6/10,000 hospital admissions. The authors found that 31.1% of the patients studied had a thrombosis in more than 1 region. The incidence of thrombosis by anatomic site was as follows: 42 thromboses in the peripheral arterial system, 39 in an intracardiac region, 38 in the abdominal venous system, 36 in the deep peripheral venous system, and 28 in the cerebral vascular system. The mean age of the patients at the time of diagnosis was 4.9 years. Of the patients studied, 10.7% were neonates, 35.3% were infants younger than 1 year, and 48.4% were younger than 2 years. Most of the patients had a congenital cardiac disease and spontaneous thrombosis, and 66.1% had at least 1 acquired risk factor, the most common of which were having undergone surgery (42%) or wearing a central venous catheter (39%). A hereditary factor for the development of thrombosis was present in 54% of the patients. The most frequently observed hereditary risk factor was the MTHFR 677C-T mutation, and the second most common was the factor V Leiden mutation. Thrombosis should be considered a systemic disorder, and thrombotic patients should be evaluated with appropriate methods. Acquired and hereditary risk factors should be analyzed systematically in thrombotic patients.