Narcolepsy

Sleep disorders

Clinicals - History

Fact Explanation
Extreme daytime sleepiness. (EDS) Irresistible sleepiness and sleep attacks of brief duration (about 15 minutes).
Occurring almost daily during a period of at least six months plus a clear clinical history of cataplexy is needed for clinical diagnosis.
Extreme daytime sleepiness. (EDS)
Irresistible sleepiness and sleep attacks of brief duration (about 15 minutes).
Occurring almost daily during a period of at least six months plus a clear clinical history of cataplexy is needed for clinical diagnosis.
Cataplexy Temporary episodes of sudden loss of muscle tone while awake or when experiencing emotions. Cataplexy
Temporary episodes of sudden loss of muscle tone while awake or when experiencing emotions.
Sleep paralysis Transient inability to voluntarily move or speak during sleep. Specially during the transition between sleep and wakefulness. Sleep paralysis
Transient inability to voluntarily move or speak during sleep. Specially during the transition between sleep and wakefulness.
Hypnagogig hallucinations Abnormal visual or auditory perceptions which are experienced while falling asleep.
Narcolepsy is characterized by the classic tetrad of symptoms. Which are, EDS, cataplexy, sleep paralysis and hypnagogig hallucinations.
Hypnagogig hallucinations
Abnormal visual or auditory perceptions which are experienced while falling asleep.
Narcolepsy is characterized by the classic tetrad of symptoms. Which are, EDS, cataplexy, sleep paralysis and hypnagogig hallucinations.
Secondary emotional and social difficulties Due to the symptoms of their disorder people experience embarrassment, feelings of loss of self-worth and academic decline in adolescents.
They also avoid social situations that would precipitate cataplexy or draw attention to the degree of somnolence.
Secondary emotional and social difficulties
Due to the symptoms of their disorder people experience embarrassment, feelings of loss of self-worth and academic decline in adolescents.
They also avoid social situations that would precipitate cataplexy or draw attention to the degree of somnolence.

Clinicals - Examination

Fact Explanation
Thorough and complete neurological examination. In order to exclude structural neurological abnormalities which can mimic narcolepsy.
Except for atonia and areflexia in patients having active cataplexy, neurological examination should be normal.
Thorough and complete neurological examination.
In order to exclude structural neurological abnormalities which can mimic narcolepsy.
Except for atonia and areflexia in patients having active cataplexy, neurological examination should be normal.
Cardiovascular examination. Look for arrhythmias, aortic stenosis which can cause drop attacks. Cardiovascular examination.
Look for arrhythmias, aortic stenosis which can cause drop attacks.

Investigations - Diagnosis

Fact Explanation
12-lead electrocardiography and echocardiography. To exclude cardiac causes giving rise to drop attacks. Example: Aortic stenosis. 12-lead electrocardiography and echocardiography.
To exclude cardiac causes giving rise to drop attacks. Example: Aortic stenosis.
Brain Imaging and EEG. When drop attacks caused by seizure episodes needed to be excluded. Brain Imaging and EEG.
When drop attacks caused by seizure episodes needed to be excluded.
Polysomnogram- multiple sleep latency test (MSLT). To diagnose according to diagnostic criteria.
Average sleep latency < 8 minute or presence of two sleep-onset REM periods (SOREMPs) during the multiple sleep latency test (MSLT) are considered positive polygraphic abnormalities in the diagnosis.
Polysomnogram- multiple sleep latency test (MSLT).
To diagnose according to diagnostic criteria.
Average sleep latency < 8 minute or presence of two sleep-onset REM periods (SOREMPs) during the multiple sleep latency test (MSLT) are considered positive polygraphic abnormalities in the diagnosis.
Nocturnal polysomnogram. To exclude other possible causes like
periodic leg movements and obstructive sleep apnea.
Nocturnal polysomnogram.
To exclude other possible causes like
periodic leg movements and obstructive sleep apnea.
HLA type diagnostic markers. Most patients are HLA DQB1*0602 positive. Which predispose patients to the disorder.
Presence of markers is supportive of the diagnosis.
HLA type diagnostic markers.
Most patients are HLA DQB1*0602 positive. Which predispose patients to the disorder.
Presence of markers is supportive of the diagnosis.
CSF hypocretin-1 measurement. Low CSF hypocretin levels (< 110 pg/ml, one-third of mean control value) are included in the diagnostic criteria of narcolepsy. ( in the second revision of ICSD) CSF hypocretin-1 measurement.
Low CSF hypocretin levels (< 110 pg/ml, one-third of mean control value) are included in the diagnostic criteria of narcolepsy. ( in the second revision of ICSD)

Investigations - Management

Fact Explanation
Polysomnographic test- maintenance of wakefulness test (MWT) Is to assess the effect of treatment with psycho stimulants. Polysomnographic test- maintenance of wakefulness test (MWT)
Is to assess the effect of treatment with psycho stimulants.

Management - Supportive

Fact Explanation
Explanation of the diagnosis and nature of disorder having recurrences and necessity of life long treatments. Reassurance of the patient and prevention of accidents. Explanation of the diagnosis and nature of disorder having recurrences and necessity of life long treatments.
Reassurance of the patient and prevention of accidents.
Patient education on avoiding dangerous activities such as driving or operating machinery, and possible dangerous situations like occurrence of a drop attack while climbing stairs, swimming , and suggest suitable precautions. Example- having a companion while going on heights, having a life preserver when swimming. Prevents accidents. Patient education on avoiding dangerous activities such as driving or operating machinery, and possible dangerous situations like occurrence of a drop attack while climbing stairs, swimming , and suggest suitable precautions. Example- having a companion while going on heights, having a life preserver when swimming.
Prevents accidents.
Avoid alcohol and heavy meals. Disturbs the sleep- wake cycle and can give rise to alcohol-dependent sleep disorder. Avoid alcohol and heavy meals.
Disturbs the sleep- wake cycle and can give rise to alcohol-dependent sleep disorder.

Management - Specific

Fact Explanation
Regular/planned day time napping. Relieves drowsiness for one or two hours. Regular/planned day time napping.
Relieves drowsiness for one or two hours.
Maintaining regular sleep- wake patterns. relieves daytime drowsiness.
The combination of planned daytime naps and maintaining regular nocturnal sleep times produce significant reduction in severity of daytime sleepiness in treated narcoleptics.
Maintaining regular sleep- wake patterns.
relieves daytime drowsiness.
The combination of planned daytime naps and maintaining regular nocturnal sleep times produce significant reduction in severity of daytime sleepiness in treated narcoleptics.
Medical Therapy 1) CNS stimulants - Amphetamine, Methamphetamine, Dextroamphetamine, Methylphenidate - considered main treatment for sleepiness associated with narcolepsy.
2) Non-amphetamine wakefulness promoting medication - Modafinil and Armodafinil.
3) Sodium Oxybate - Is a rapidly acting sedative. Improves cataplexy and reduces daytime somnolence.
4) Tricyclic antidepressants and fluoxetine - effective in the treatment of cataplexy.
Medical Therapy
1) CNS stimulants - Amphetamine, Methamphetamine, Dextroamphetamine, Methylphenidate - considered main treatment for sleepiness associated with narcolepsy.
2) Non-amphetamine wakefulness promoting medication - Modafinil and Armodafinil.
3) Sodium Oxybate - Is a rapidly acting sedative. Improves cataplexy and reduces daytime somnolence.
4) Tricyclic antidepressants and fluoxetine - effective in the treatment of cataplexy.

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