Oral l-carnitine as treatment for narcolepsy without cataplexy during pregnancy: A case report

A case of Kleine-Levin syndrome arising during chemotherapy: efficacy of oral L-carnitine

A woman in her 50 s with Kleine-Levin syndrome (KLS) was referred to our sleep clinic for recurrent episodes of sleep hypersomnia lasting for two to 3 days, despite attempts to remain awake. These episodes were unaccompanied by anxiety or depression, increased appetite, increased sex drive, irritability, or hallucinations, and had first appeared during chemotherapy for malignant lymphoma. Video polysomnography revealed mild obstructive sleep apnea syndrome (apnea-hypopnea index 7.9/h), but no other abnormalities. All blood tests and brain imaging investigations, including brain MRI and A 123I-ioflupane SPECT, yielded normal results. Oral L-carnitine was found to be effective for shortening the period of hypersomnolence, reducing the degree of hypersomnolence, and prolonging the inter-episode period. Since it has been reported that alkylating agents may induce carnitine deficiency, the present observations appear to support the involvement of carnitine in the onset of KLS.

Oral L-Carnitine used to treat narcoleptic type 1 patient during pregnancy - A case report

Narcolepsy type 1 is a sleep disorder characterized by excessive daytime sleepiness (EDS), sleep fragmentation, hypnagogic hallucinations, sleep paralysis, and cataplexy. Stimulant medications such as modafinil and amphetamines are the first-line medications for treating sleepiness. However, the management of narcolepsy during special circumstances of life such as pregnancy is complex. MMDM is a 34-year-old female with Narcolepsy type 1 treated with modafinil (400mg/d) and citalopram (20mg/d). Before she become pregnant, modafinil and citalopram were replaced for L-Carnitine 510mg/d with good outcome. She underwent an usual pregnancy and was submitted to a term cesarean delivery without child-birth complications. This is the first description of oral L-Carnitine such an alternative to treatment narcolepsy type 1 during pregnancy. Treat these patients is not easy but care narcolepsy pregnant is a challenging even bigger. In a disease without many treatment options, L-Carnitine can be used to treat daytime sleepiness during pregnancy in narcolepsy.

Genetics of narcolepsy

Narcolepsy is a term that was initially coined by Gélineáu in 1880 and is a chronic neurological sleep disorder that manifests as a difficulty in maintaining wakefulness and sleep for long periods. Currently, narcolepsy is subdivided into two types according to the International Classification of Sleep Disorders, 3rd edition: narcolepsy type 1 (NT1) and narcolepsy type 2 (NT2). NT1 is characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis and is caused by a marked reduction in neurons in the hypothalamus that produce orexin (hypocretin), which is a wakefulness-associated neuropeptide. Except for cataplexy, NT2 exhibits most of the same symptoms as NT1. NT1 is a multifactorial disease, and genetic variations at multiple loci are associated with NT1. Almost all patients with NT1 carry the specific human leukocyte antigen (HLA) allele HLA-DQB1 ^* 06:02. Genome-wide association studies have uncovered >10 genomic variations associated with NT1. Rare variants associated with NT1 have also been identified by DNA genome sequencing. NT2 is also a complex disorder, but its underlying genetic architecture is poorly understood. However, several studies have revealed loci that increase susceptibility to NT2. The currently identified loci cannot explain the heritability of narcolepsy (NT1 and NT2). We expect that future genomic research will provide important contributions to our understanding of the genetic basis and pathogenesis of narcolepsy.