MMACHC Test Coding and Billing Guidelines (CM00047, V2)
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October 20, 2015 - Updated 02.01.17

MMACHC Test Coding and Billing Guidelines (CM00047, V2)

Methylmalonic aciduria (cobalamin deficiency) cblC type, with homocystinuria (MMACHC) is associated with the most common error of vitamin B12 metabolism. Although considered a disease of infancy or childhood, some individuals develop symptoms in adulthood. However to date, the exact function of the protein encoded by this gene is not known. Therefore, MMACHC testing does not meet the clinical utility requirements for a Medicare Benefit and is considered a statutorily excluded service. Palmetto will also deny panels of tests that include the MMACHC gene.

To receive a MMACHC service denial, please submit the following claim information:

  • CPT code 81404-MMACHC, fgs
  • An Advance Beneficiary Notice (ABN) is not required for statutorily excluded services.
    • For a voluntary issued ABN, append with GX HCPCS modifier
    • To indicate a valid ABN is on file for a known statutorily excluded service, append with a GY HCPCS modifier

      Select the appropriate diagnosis for the patient
  • Enter the appropriate DEX Z-code™ identifier adjacent to the CPT code in the comment/narrative field for the following claim field/types:
    • Loop 2300 NTE01 or SV202-7 for Part A or Loop 2400 or SV101-7 for the 5010A1 837P for Part B
    • Form locator 80 for Part A or Box 19 for Part B paper claim

Reference: Sec. 1862 (1)(A) Statutory Exclusion covers diagnostic testing "except for items and services that are not reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member,…"

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