DES MOINES — State Auditor Rob Sand alleged Wednesday that both insurance companies that manage Medicaid in Iowa have breached their contracts with the state.He announced in a news conference that he sent a letter to the Iowa Department of Human Services about the cases of two quadriplegic Iowans whose care services were reduced by Amerigroup Iowa and UnitedHealthcare, which could indicate “serious concerns” for the program as a whole.In the letter, Sand asserts that the reduction of services for the two Medicaid members point to violations of contract clauses with the state as well as with federal regulations imposed on the companies through the state.“There’s a 267-page contract these (managed care organizations) signed with the state of Iowa,” Sand said.