Probable Miglustat-Induced Psychosis in a Child With Niemann-Pick Type C

Background Niemann-Pick disease type C (NP-C) is a neurodegenerative lysosomal disease in which psychiatric symptoms, such as psychosis, can also be observed. Miglustat is indicated in cases with progressive neurological manifestations, and although there have been studies reporting that miglustat completely cures psychosis, it has been recently observed that miglustat may also trigger psychosis. We report on a rare case of probable miglustat-induced psychosis in a patient with NP-C. Case A 21-year-old female patient presented with a complaint of social isolation that started at the age of 6 years. During clinical follow-up, the patient's clinical progress deteriorated, and ocular apraxia, ataxia, seizures, and dementia developed at the age of 15 years. A genetic investigation was performed, and a homozygous p.P120S (c.358C > T) variant was detected in the NPC2 gene. Miglustat was initiated at the age of 15 years, and during the 6 months of treatment, psychotic symptoms such as unwarranted anger, suspiciousness, and delusions developed. Consequently, the miglustat was discontinued by the parents of the patient, and the psychosis completely disappeared. The patient has experienced no further psychotic episodes in the approximately 5.5 years following the discontinuation of therapy. Conclusion Although a positive effect of miglustat on neurological and psychiatric symptoms has been reported, there exists a risk of psychosis being triggered. To the best of our knowledge, this is the first case of pediatric NP-C to develop psychosis after miglustat to be reported in literature. Further studies of such cases are needed to understand the impact of miglustat on psychiatric symptoms in NP-C.