Mild splenic sequestration crises in sickle-hemoglobin C disease.

Acute splenic sequestration crisis ( ASSC ), a common complication in homozygous sickle cell anemia, has been described infrequently in sickle-hemoglobin C (SC) disease in the absence of high altitude exposure. In this report, we describe three children with hemoglobin SC disease who developed episodes of ASSC that were milder than those generally described in sickle cell anemia. In one patient, an antecedent triggering event was not recognized. The other two children may have had a predisposing cause for massive intrasplenic sickling in that one had an associated mononucleosis syndrome and the other an episode of hypovolemic shock following severe epistaxis. ASSC may occur in patients with SC disease and does not necessarily require a hypoxic trigger associated with high altitudes.