PB0979 - Venous Thrombosis Secondary to Vitamin B12 Deficiency may not be solely explained by hyperhomocysteinemia: about 10 Cases

Background: Vitamin B12 Deficiency is associated with high thrombotic risk due to etiologies (chronic inflammatory bowel disease, intestinal tuberculosis, celiac disease, pernicious anemia) and hyperhomocysteinemia.

Aims: describe clinical and etiological profile of patients with B12 deficiency, revealed by a thrombotic event.

Methods: Retrospective Descriptive Study with a period of 3 months (08/2023-10/2023), recruiting 10 cases of Vitamin B12 Deficiency identified among 120 patients consulting for an etiological assessment of Venous Thromboembolic Disease (VTE) in Internal Medicine Department of Ibn Sina University Hospital.

Results: Seven women. Median age of 42 years (27-72). Two had history of miscarriages, and one patient was using oral contraceptives. Six cases of unilateral lower limb venous thrombosis (VT): 5 deep vein thromboses (DVT) and 1 superficial thrombosis. Four cases of unusual site VT: 2 portal vein, 1 spleno-mesenteric, and 1 inferior vena cava. Macrocytic anemia in 6 patients with a median hemoglobin of 10.47 g/dL; hyperhomocysteinemia (mean 20 µmol/L) along with decreased vitamin B12 levels. Rest of the malabsorption panel was disturbed in 4 patients. B12 deficiency was explained by Crohn's disease in 4 patients, Biermer's disease in 2, intestinal tuberculosis in 2, celiac disease in 1, and a dissociation syndrome of vitamin B12 and its carrier proteins in 1 (after normal etiological assessment). The etiological assessment of VTE was negative: nephrotic and hepatic panel, protein C, S, antithrombin III, antiphospholipid antibodies, cardiac and neoplastic investigations. Curative anticoagulant with Rivaroxaban for a minimum of 6 months, with subcutaneous B12 supplementation, was initiated in all patients, and specific treatment for the underlying pathology (gluten-free diet in celiac disease, anti-tubercular treatment in intestinal tuberculosis, and anti-TNF treatment for Crohn's disease). All patients showed a favorable outcome

Conclusion(s): Our study confirms multifactorial nature of thromboembolic disease and encourages us to maintain rigor in our etiological approach to any thrombotic event.