Serum vitamin B12-binding proteins in a case of eosinophilic leukemia.
A patient with subacute eosinophilic leukemia is presented, with full recognition of the controversy surrounding that entity. Serum vitamin B12 and B12-binding protein studies and simultaneous complete blood counts were done before and during 6 months of high-dose, intermittent combination chemotherapy. The patient presented with extremely high levels of serum vitamin B12, unsaturated B12-binding capacity, and transcobalamin I, all of which resembled the highest values seen in chronic myelogenous leukemia. Serial studies, during and after remission induction, showed a precipitous fall of serum vitamin B12 and unsaturated B12-binding capacity to normal levels. The data show that transcobalamin I levels, which eventually reached low-normal range, correlate best with the level of circulating and bone marrow eosinophils. Transcobalamin II and serum third binder appeared to be normal throughout the patient's course. The B12-binding protein abnormalities are not considered diagnostic of eosinophilic leukemia.
D000328:Adult; D000510:Alpha-Globulins / Q000032:analysis; D001609:Beta-Globulins / Q000032:analysis; D003520:Cyclophosphamide / Q000627:therapeutic use; D003561:Cytarabine / Q000627:therapeutic use; D004804:Eosinophils / Q000473:pathology*; D006801:Humans; D007938:Leukemia / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy; D008297:Male; D011241:Prednisone / Q000627:therapeutic use; D011485:Protein Binding; D012075:Remission, Spontaneous; D014750:Vincristine / Q000627:therapeutic use; D014805:Vitamin B 12 / Q000097:blood*
D000510:Alpha-Globulins; D001609:Beta-Globulins; D003561:Cytarabine; D014750:Vincristine; D003520:Cyclophosphamide; D014805:Vitamin B 12; D011241:Prednisone