The treatment of sickle cell anemia with induced hyponatremia.

Since the rate of polymerization of sickle hemoglobin is exquisitely dependent on its concentration, a small reduction in intracellular hemoglobin concentration should cause a significant inhibition of sickling. In three patients with homozygous sickle cell anemia, sustained hyponatremia was induced by a program consisting of a high fluid intake, a low salt diet and a vasopressin analog, DDAVP. During periods of hyponatremia, mean corpuscular hemoglobin concentration (MCHC) fell 13% and in vitro sickling was reduced as assessed by morphology and oxygen affinity. The frequency and duration of sickle cell crises appeared to be decreased during periods when patients were hyponatremic. These preliminary results indicate that reduction in intracellular hemoglobin concentration is an effective approach to the treatment of sickle cell anemia.