For services performed on or after Dec. 17, 2004, a positive fasting beta cell autoantibody test can serve as an alternative to insulinopenia for the updated C-peptide testing requirement, the Centers for Medicare and Medicaid Services said Feb. 10.
Insulinopenia is a fasting C-peptide level less than or equal to 110 percent of the lower limit of normal. Patients with renal insufficiency must have a fasting C-peptide level that is less than or equal to 200 percent of the lower limit. The "lower limit" is contingent on the laboratory's measurement method.
To read more, go to www.cms.hhs.gov/manuals/pm_trans/R27NCD.pdf.