"Recovery" of In-111 Chloride uptake in spleen and bone marrow, after chemotherapy for acute leukemia

A man with acute myelogenous leukemia, treated with chemotherapy, had a decrease in circulating formed blood elements. Bone marrow biopsy revealed necrosis. Imaging with In-Ill chloride demonstrated activity in the liver, but not in the spleen or bone marrow. Eighteen days later, the circulating blood count had risen; a repeat bone marrow biopsy showed the return of blood cell precursors. Follow-up In-111 chloride study at that rime showed uptake in both the spleen and vertebrae, in addition to the liver. Hence, the spleen and bone marrow had "recovered" function. In the present study, potential causes of this change are discussed.