How can cobalamin injections be spaced in long-term therapy for inborn errors of vitamin B12 absorption?

► Inborn errors of vitamin B12 absorption are a treatable cause of pancytopenia. ► These include Imerslund-Gräsbeck disease and hereditary intrinsic factor deficiency. ► Life-long parenteral cobalamin (Cbl) injections are life saving. ► Such a treatment easily corrects hematological and metabolic abnormalities. ► Our data on 7 patients suggest that 1 mg of IM Cbl bi-annually is sufficient.