Increased Prevalence of Thromboembolic Events in Patients with Congenital Dyserythropoietic Anemia Type I

Abstract – Introduction: Congenital dyserythropoietic anemia type I (CDA-I) is a rare disorder of erythropoiesis. All CDA-I patients are expected to have iron overload and chronic hemolysis. Patients with severe anemia may undergo splenectomy. Hemochromatosis, chronic hemolysis, and splenectomy are all found to increase risk for thromboembolism in thalassemic patients. As CDA-I patients have similar findings, we sought to evaluate prevalence of thromboembolic events (TEEs) in these patients. Methods: A retrospective case-control study was conducted, including 110 CDA-I patients (study group) and 326 age- and sex-matched iron deficiency anemia patients of the same ethnicity (control group). Patients were risk-stratified using Risk Assessment Models for thromboembolism. Results: We identified 3 cases (2.7%) with TEEs in the CDA group and 1 case (0.3%) in the control group. All patients were females. VTE risk scores were low to moderate for CDA patients and higher for IDA patient. When compared to control group, CDA-I patients were nine times more likely to develop TEE (OR 9.11, 95% CI = 1.15–185.27, p = 0.057). All 3 CDA patients had a history of remarkable hemolysis and iron overload. Two underwent splenectomy. Conclusion: These findings show that CDA patients appear to be at increased risk for TEEs. Plain Language Summary Congenital dyserythropoietic anemia type I is a rare disorder of erythropoiesis where all patients are expected to suffer from iron overload and chronic hemolysis. Some of them may undergo splenectomy. All these factors were found to increase the risk of thrombosis. Deep vein thrombosis and pulmonary embolism are associated with increased long-term morbidity, functional disability, and mortality. Prevalence of thrombosis in CDA-I patients have not been previously studied, mainly due to rarity of this disorder. In this study, we evaluated thrombosis risk in 110 CDA-I patients and compared them to age- and sex-matched control group (326 subjects) of the same ethnicity. We found 3 cases (2.7%) with thromboembolic events in the CDA group and 1 case (0.3%) in the control group. These findings suggest increased risk of thrombosis in CDA-I patients, especially when analyzing all patients’ characteristics. A high index of suspicion may help in earlier diagnosis and intervention in these patients.