Age at the time of splenectomy. Overall, 150 (59%) of 254 patients had a history of splenectomy at enrollment with median age at splenectomy of 4.1 years (range, 0.4-37.8 years). Among the cohort of Amish patients, 93% had a splenectomy at a median age of 1.6 years (range, 0.6-28.2 years). Among the cohort of non-Amish patients, 50% had a splenectomy at a median age of 5.0 years (range, 0.4-37.8 years).