Tremor and Myoclonus Due To Action Myoclonus Renal Failure Syndrome (AMRFS)

A 22 year old women presented with a bilateral jerky tremor, stimulus-sensitive myoclonus, difficulty with tandem gait, and rapidly progressive renal failure with nephrotic-range proteinuria. Renal biopsy demonstrated focal segmental glomerulosclerosis (FSGS). The video shows postural and action tremor of her outstretched hands, with myoclonus (stimulus sensitivity is demonstrated, and jerks are evident when drawing the Archimedes spiral). Genetic testing for mutations in the SCARB2 gene and other genetic causes of FSGS revealed pathogenic variants in the SCARB2 gene, strongly supporting the diagnosis of AMRFS, also known as myoclonic nephropathy or progressive myoclonic epilepsy (PME) type 4. For full case details see http://ja.ma/29fGpJz For video documentation of her tremors 2 months after a renal transplant, see    • Movement Disorder Due to Action Myoclonus ...