Bone marrow scintigraphy using 111Indium chloride in patients with aplastic anemia

Bone marrow scintigraphy using 111Indium chloride (111In-chloride) was performed in 18 patients with aplastic anemia. The scintigrams were taken 48 hours after an intravenous injection of 111In-chloride 3 mCi. The distribution patterns on scintigram were classified into 5 types: Type I (4 cases) showed no accumulation, Type II (6 cases) showed low accumulation in usual bone marrow sites. Type III (7 cases) showed island-like distribution in bone marrow sites. Type IV, although no case was included in the 18 patients, shows uneven distribution between pelvis and sternum or vertebrae. Type V (one case) showed almost normal accumulation in usual bone marrow sites. Bone marrow uptake of 111In-chloride correlated well with the cellularity of bone marrow. There was a tendency for the cases of markedly increased saturated iron-binding capacity to show increased renal activity. In type III, both the percentage of cases who had been treated and the count of reticulocytes were higher than those in the other types, which suggested that island-like distribution on scintigram showed the regeneration responded to the therapy, and related to the erythropoietic function. (author)