[Diagnosis of childhood narcolepsy and significance of HLA in its diagnosis].
OBJECTIVE
Narcolepsy is a lifelong sleep disorder characterized by excessive daytime sleepiness, and features of rapid eye movement (REM) sleep, such as cataplexy, sleep paralysis and hypnagogic hallucinations. The present study aimed to investigate the diagnostic basis of childhood narcolepsy and possible role of HLA Class II alleles in the onset of this disease.


METHODS
The clinical data of 40 narcoleptic children were analyzed. All patients received Multiple Sleep Latency Test (MSLT) and they were analyzed in combination with clinical features. Polymerase chain reaction/sequence specific primers (PCR/SSP) methods were used to detect the HLA-DRB1 and DQB1 alleles.


RESULTS
Narcolepsy was diagnosed in 40 children. The age range was 3 to 14 years (mean 8.5 +/- 2.5 years), 29 were male and 11 female. Their mean course of disease was 6.5 months, 14 patients (30%) were less than 3 months old, 21 patients (52%) were less than 6 months old. All the patients had excessive daytime sleepiness, cataplexy appeared in 37 cases, hypnagogic hallucination in 22 and sleep paralysis in 6. Mean sleep latency on MSLT was less than 5 min, the average number of sleep-onset rapid eye movement (SOREM) was 4.33 +/- 0.26 episodes (2-5 episodes), the latency of SOREM episodes were 4.0 +/- 1.8 min (0.25-4.9 min). Thirty-five patients were DRB1 1501 and DQB1 0602 positive (Pc < 0.01), 2 were DRB1 1502 and DQB1 0601 positive, while 3 were DRB1 15 and DQB1 6 negative.


CONCLUSIONS
Some pediatric patients with narcolepsy were different from adult patients in that the pediatric cases had a sudden onset and shorter disease course. Diagnosis of this disease was based on the clinical manifestations, MSLT and absence of any medical or psychiatric disorder that could account for the symptoms. The authors demonstrated that DRB1 1501 and DQB1 0602 were susceptibility genes for narcolepsy and those who were DRB1 15 negative could not be excluded.
Wu
Hu-sheng
HS
Division of Neurology, Department of Neurology and Center of Rehabilitation, Beijing Children's Hospital, Capital University of Medical Sciences, Beijing 100045, China.
Guo
Yu-hong
YH
Zou
Li-ping
LP
Han
Fang
F
Zhang
Wu-chang
WC
Fang
Fang
F
Xiao
Jing
J
Ding
Chang-hong
CH
Li
Jing
J
Chen
Chun-hong
CH
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006801:Humans; D007223:Infant; D008297:Male; D009290:Narcolepsy / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D016133:Polymerase Chain Reaction
D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains