MERRF

MERRF (myoclonic epilepsy with red ragged fibres) is a rare, multisystem mitochondrial disorder

Patients usually present in late adolescence or early adulthood with 1,2,3

  • myoclonus
  • epilepsy
  • cerebellar ataxia
  • intellectual disability
  • vision and/or hearing loss
  • cardiomyopathy with Wolff-Parkinson-White syndrome
  • short stature

The diagnosis of MERRF is based on clinical symptoms (myoclonus, epilepsy, ataxia) and ragged-red fibres on muscle biopsy 3.

Genetics

The mitochondrial gene MT-TK, which encodes tRNALys, is the most commonly affected with an A-to-G transition at nucleotide 8344 (80%) 3.

Markers
  • serum and CSF lactic acidosis
  • high CSF protein

Neuroradiological features of MERRF can be seen on CT and/or MRI 1,2:

On imaging consider

  • MELAS: differentiated by the presence of strokes in MELAS
Toxic and metabolic encephalopathies
Share article

Article information

rID: 39666
Section: Syndromes
Tag: cases
Synonyms or Alternate Spellings:
  • Myoclonic epilepsy with red-ragged fibres (MERRF)
  • Myoclonic epilepsy with red-ragged fibres

Support Radiopaedia and see fewer ads

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.