MERRF syndrome

This code identifies Myoclonic Epilepsy with Ragged Red Fibers (MERRF) syndrome, a rare, progressive neurodegenerative disorder caused by mitochondrial DNA mutations. It is characterized by myoclonus, ataxia, generalized epilepsy, and muscle weakness, often with a distinctive "ragged red fiber" appearance on muscle biopsy. The condition typically manifests in childhood or adolescence and can involve other organ systems.

Assign this code when documentation clearly indicates a diagnosis of MERRF syndrome. This diagnosis is typically established through a combination of clinical presentation (myoclonus, ataxia, epilepsy), muscle biopsy findings, and genetic testing confirming mitochondrial DNA mutations. Use this code for patients undergoing diagnostic workup, treatment, or management of MERRF syndrome.

• Ensure documentation specifies "MERRF syndrome" or provides sufficient clinical detail to confirm this specific mitochondrial disorder.
• Do not confuse MERRF with other mitochondrial encephalomyopathies; verify the specific syndrome.
• Code any associated neurological manifestations (e.g., specific types of epilepsy, ataxia) as secondary diagnoses.