Ct showed splenomegaly. blood work had high rdw, low creatinine, and low mch (anemia?); other cbc normal. how could anemia be related to spleen?

Splenomegaly: It isn't clear from what you say whether your hemoglobin itself is truly abnormal or whether just the RDW and MCH are altered. These in themselves do not define anemia. A large spleen may be related to trapping altered red cells, or actually making more blood (extramedullary hemopoiesis.) Often a high RDW means that there is increased production of immature red cells after destruction in spleen