PP03.9 – 2553: Niemann-Pick disease type C and sleep disorders

Abstract

Objective Niemann-Pick disease type C (NP-C) is a rare and progressive autosomal recessive disease leading to disabling neurological manifestation and premature death. NP-C is characterized by visceral, neurological and psychiatric manifestation. Sleep disturbances except for cataplexy are described only exceptionally. Methods Twenty-two NP-C patients have been followed in the Czech Republic in the past 20 years. Fourteen of them are still alive, 8 have died. Miglustat (Zavesca ®, Actelion Pharmaceuticals Ltd) has been authorized for the NP-C treatment in the Czech Republic since 2011. Over the past 4 years, 16 patients have been included in the national NP-C miglustat register. Results Seven cases of juvenile, 7 cases of adult and 6 cases of late infantile forms were found; in 2 patients infantile NP-C type was diagnosed. Cataplexy was found in 5 patients (3 with late infantile, 2 with juvenile form). The mean age at onset of cataplexy was 7.5±3.8 years (age range from 2.5 to 12 years). In two cases cataplexy continued during the follow-up period for 1 and 4 years respectively. One child, who died at the age of 6 years, had cataplexy from the first NP-C clinical symptoms till his death. In the last two patients cataplectic attacks were observed only for a limited period of the disease. In both of them cataplexy disappeared when neurological disability accompanied by intellectual deterioration had increased. Mildly increased sleepiness during the day (without cataplexy) was seen only in 1 patient (who suffered also from a mild sleep breathing disorder), while 6 patients complained frequently about restless and disturbed sleep. Conclusion Cataplexy appeared predominantly in preschool and school children. A severe clinical course of the disease is probably the reason why sleep problems, except for cataplexy, are overlooked and underdiagnosed.