Paraneoplastic myoclonus (Q100581)

Paraneoplastic myoclonus may occur in the setting of cancer without opsoclonus and be either a component of a multifocal neurological presentation (e.g. in autoimmune encephalopathy) or occur in isolation. The myoclonic jerks may be focal or whole body and may be mistaken for tremor. Accompanying neural autoantibodies may be found (e.g. collapsing response mediator protein 5-IgG) and screening for an underlying cancer is appropriate, but it is also important to exclude other potential etiologies (e.g. drug induced myoclonus). Associated autoantibodies: AMPA-R (amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antibodies); amphiphysin; ANNA-1(anti-Hu) (antineuronal nuclear autoantibody type 1); ANNA-2(anti-Ri) (antineuronal nuclear autoantibody type 2); ANNA-3 (antineuronal nuclear autoantibody type 3); CRMP5(anti-CV2) (collapsin response mediator protein 5); GABABR (Gamma-aminobutyric-acid type-B autoantibodies); Ma1; Ma2; mGluR5 (metabotropic glutamate receptor antibody type 5); NMDA-R (N-methyl-D-aspartate receptor autoantibodies); PCA-2 (purkinje cell cytoplasmic autoantibody type 2); PCA-Tr (purkinje cell autoantibody-Tr);