Narcolepsy-cataplexy and psychosis: a case study.

AIMS: To report a challenging patient a girl who developed narcolepsyy with cataplexy (NT1) and a psychosis during adolescence. To discuss diagnostic and therapeutic challenges of the comorbid cases.

CASE REPORT: A 14-year-old girl was referred to Sleep and Epilepsy Unit for excessive daytime sleepiness, impaired nocturnal sleep, binge eating and weight gain, over the last year. After being diagnosed with a NT1 the patient was treated with modafinil and sodium oxybate. She was hospitalized for psychotic symptoms after starting NT1 treatment. Withdrawal of the narcolepsy treatment and initiation of haloperidol 1 mg/day (the only antipsychotic treatment she could tolerate) improved the delusions, hallucinations and dysphoria but worsened the narcolepsy symptoms. Polysomnography showed fragmented nocturnal sleep and five sleep REM onset periods in MSLT. Positive HLA-QB1*06:02 and undetectable level of hypocretine in the cerebrospinal fluid were found. MRI and CT-scan were normal. Diagnostic Interview for Genetic Studies Adapted for Narcolepsy (DIGSAN) questionnaire confirmed that patient presented a dual diagnostic NT1 and psychotic symptoms. The last sleep follow-up while on psychopharmacological treatment, showed an increased sleep efficiency index. She currently has severe somnolence, obesity, and partial cataplectic attacks along with normal mood, academic failure and social isolation.

CONCLUSION: The coexistence of narcolepsy with psychoses is a rare clinical entity, more frequent in adolescents than in adults. The comorbidity of the two illnesses worsens clinical and therapeutic prognosis and also suggests interesting pathophysiological hypotheses.