ICD-10-CM 2027
ICD-10 code for MERRF syndrome
From the official ICD-10-CM alphabetic index entry “MERRF syndrome (myoclonic epilepsy associated with ragged-red fiber)”. Page updated September 29, 2026.
About coding MERRF syndrome
The ICD-10-CM code for MERRF syndrome is E88.42 (MERRF syndrome).
Within E88.4 (mitochondrial metabolism disorders), E88.42 is specifically for MERRF syndrome. Related codes cover mitochondrial metabolism disorder, unspecified (E88.40), MELAS syndrome (E88.41), disorders of mitochondrial tRNA synthetases (E88.43) and other mitochondrial metabolism disorders (E88.49).
Use an additional code for: codes for associated conditions.
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
Common questions about MERRF syndrome ICD-10 codes
What is the ICD-10 code for MERRF syndrome?
- E88.42 — MERRF syndrome.
Is E88.42 billable?
- Yes. E88.42 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can E88.42 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict E88.42 as a principal diagnosis.
Is E88.42 a CC or MCC?
- E88.42 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.