A 9-year-old boy presented with complaints of excessive duration of sleep, increased appetite, weight gain, excessive daytime sleepiness, loss of interest in sports activities, irritability and snoring since 1.5 years after he was shifted to a residential school.
Before attending residential school, he used to follow a regular sleep schedule, with bedtime at 10 p.m. He did not have any issue with sleep onset and used to sleep alone in the bed. According to his father, he used to sleep in supine position and did not show any sign of sleep-related breathing disorder. His mother used to wake him up at 5 a.m. and he usually left the bed within 10 minutes, feeling fresh. He was good in studies till the age of 7 years and had many friends.
After 6 months of shifting to residential school, his father received complaints from the school regarding deterioration in studies and sleeping in the class. His teachers had also noticed that he was gaining weight and losing interest in sports activities. Then, his father took him back home before 1 year.
After bringing him home, since the past 1 year, his parents noticed a gross change in his appetite with an increase in frequency and amount of food. A delay in meeting his demand of food used to result in irritability shown by the child. He continued to put on weight at home. His parents also noticed an increase in the time spent in sleep. For the past 1 year, he started feeling sleepy by 9 p.m. During the night, he would snore and spent most of his sleep in prone position. On some occasions, his father had found saliva on the pillow in the morning. His parents were not able to wake him up till 7 a.m., that too, with a lot of difficulty. After waking up, he took nearly an hour to become active. In addition, he started taking 3–4 hour nap after lunch each day. If he was not allowed to take nap any day, he would fall asleep by 5 p.m to wake up at 7 a.m. in the morning. Any force to avoid nap resulted in irritability. He lost interest in sports activities since then.
The child's father also noticed frequent memory lapses resulting in misplacing his belongings. There was no history to suggest childhood depression, frequent rhinitis, tonsillitis, attention deficit hyperactivity disorder, restless leg syndrome, cataplexy, hypnogogic or hypnopompic hallucinations, sleep paralysis or any other parasomnia. There was no evidence of any neurological disorder, epilepsy, head trauma or substance abuse. His birth history and developmental history were noncontributory. Family history was also nonremarkable.
His craniofacial examination showed presence of central obesity, dental overjet, Mallampatti grade IV upper airway, submental fat and high arched palate. Epsworth Sleepiness Scale score was 24. His weight was 56 kg and height was 132 cm, leading to body mass index (BMI) of 32.18. His neck circumference was 34 cm.
Mental status examination showed normal psychomotor activity. Child was irritable on occasions following trivial issues and was reluctant to comply with examination procedure. He failed to comply when higher mental functions were being tested.
His lateral neck skiagram showed adenoid hypertrophy  and magnetic resonance imaging (MRI) brain was noncontributory. IQ assessment was also ordered. Since the child did not comply on the first day, the tests were performed after 2 days. At the time of administering tests, child was in better mood and performed all the tests. On developmental screening test, he attained a score of 90; on Vineland Social Maturity scale, his score was 70; on Malin's Intelligence Scale (Indian Adaptation) – Wechsler Intelligence Scale for Children (WICS) (performance test and verbal test), he attained a score of 70 each. Thus, the comprehensive score was 75.
Neck skiagram showing adenoid hypertrophy in the child (lateral view)
Considering the clinical picture, diagnosis of obstructive sleep apnea was made and narcolepsy without cataplexy and KLS were kept as differential diagnoses. Consequently, a level-I video polysomnography followed by multiple sleep latency test (MSLT) was ordered.
Level I polysomnography was done with a total recording time of 452 minutes. Total sleep time was 362 minutes. Objectively, the boy had sleep efficiency of 90% (100 × Total Sleep Time (TST)/ Sleep Period Time (SPT)); sleep onset latency of 44 minutes; Rapid Eye Movement (REM) latency of 187minutes and Wake after Sleep Onset (WASO) of 47 minutes. During the study night, N1 was 12%; N2 was 48%; N3 was 18% and REM was 22%. Hypnogram suggested frequent arousals . He spent most of time in right lateral position  and Respiratory Disturbance Index (RDI) was 2 (REM=4; Non Rapid Eye Movement (NREM)=1). Respiratory events were position dependent. Average saturation during REM was 97% and during NREM was 98%. Oxygen saturation dropped to 87% during REM and 94% during NREM. Snoring was also observed with an index of 8.9 without any effect of sleep stage.
Hypnogram showing poor maintenance of sleep
Hypnogram showing frequent shifting of body position during sleep
MSLT was done the following day. Four naps were recorded as per the standard protocol . Results of this test are depicted in .
Multiple sleep latency test report