Blood volume of children with leukemia.

Blood volume was measured using 125iodinated human serum albumin in 27 children with acute lymphoblastic leukemia, and in 7 children with various types of leukemia. Total blood volume was normal in patients without marked enlargement of spleen and liver, and increased progressively as spleen and liver size increased. The hypervolemia was entirely due to expansion of plasma volume. In the children with marked hepatosplenomegaly, only hematocrit (but not red cell mass) was below the normal range in most cases. Both hematocrit and red cell mass were subnormal in the majority of patients without considerably enlarged spleen and liver. Therefore, anemia in children with marked hepatosplenomegaly may be partly caused by hemodilution of red blood cells in expanded plasma volume.