**10. IVIg in therapy of narcolepsy with cataplexy (NC)**

Narcolepsy with cataplexy (NC) is caused by substantial loss of hypocretin neurons. NC patients carry the HLA-DQB1\*0602 allele suggesting that hypocretin neuron loss is due to an autoimmune attack.

There are some case studies that report that IVIg treatment initiated before 9 months disease duration has some clinical efficiency. The unaffected CSF hypocretin-1 levels and lack of autoantibodies suggest that any autoimmune process occurs very early in NC. The final IVIg effect needs to be investigated in RCTs (Knudsen et al, 2010).
