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E71.42

E71.42Carnitine deficiency due to inborn errors of metabolism

Billable / specific codeICD-10-CM

E71.42 is a billable, specific ICD-10-CM code for carnitine deficiency due to inborn errors of metabolism. It is valid for submission on a claim.

Code also

Both codes may be needed to describe the encounter fully. Sequencing depends on the reason for the visit.

  • associated inborn error or metabolism

Other codes that can never be billed with E71.42

These codes carry an Excludes1 note pointing at E71.42. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading E71.42 alone.

  • E71.511Neonatal adrenoleukodystrophy

Risk adjustment

E71.42 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

E71.42 is named in 5 Medicare coverage policies 5 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A54095Billing and Coding: Nerve Conduction Studies and Electromyography
  • A54095Billing and Coding: Nerve Conduction Studies and Electromyography
  • A56416Billing and Coding: Assays for Vitamins and Metabolic Function
  • A57123Billing and Coding: Nerve Conduction Studies and Electromyography

How E71.42 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to E71.42.

  • Deficiency, deficientcarnitinedue toinborn errors of metabolism

Related codes at this level

Codes that share E71.4. If E71.42 is not quite right, the correct code is usually one of these.

Questions about E71.42

Is E71.42 a billable ICD-10-CM code?
Yes. E71.42 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does E71.42 sit in the tabular list?
Endocrine, nutritional and metabolic diseases (E00-E89), in the block Metabolic disorders (E70-E88).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.