1368 Unleashing Dreams: REM Sleep Without Atonia as a Hidden Biomarker in Pediatric Narcolepsy with Cataplexy

Abstract Introduction REM sleep without atonia (RSWA) is characterized by excessive muscle activity during rapid eye movement (REM) sleep on polysomnography (PSG), where normal physiologic muscle paralysis is absent. This finding can be incidental or associated with conditions like REM sleep behavior disorder (RBD), narcolepsy, or medication effects (e.g., SSRIs/SNRIs). It may predict neurodegenerative diseases but requires clinical correlation, as no dream enactment behavior confirms isolated RSWA. This case presents RSWA in a pediatric patient with narcolepsy and cataplexy, highlighting its diagnostic and management implications in young populations. Report of case(s) A pediatric female presented for narcolepsy with cataplexy follow-up, reporting significant daytime sleepiness and attacks, improved on therapy. Symptoms included fragmentation, vivid dreams, rare paralysis/hallucinations, and emotion-triggered cataplexy (muscle weakness). Patient was taking SSRI for mood; with cataplexy improved but ongoing. Diagnostic PSG/MSLT confirmed narcolepsy: PSG showed borderline mild obstructive sleep apnea, sleep fragmentation, short REM latency, RSWA without observed enactment (patient-reported), PLMs with low ferritin and upper extremity movements. MSLT revealed short sleep latency, with multiple SOREMPs. Mild OSA was unlikely to be driving the sleepiness, and nasal treatments had been discontinued due to side effects. PLMs, which are often worsened by SSRI use and commonly seen in narcolepsy, were linked to low iron levels, although oral supplementation proved intolerable. Management involved discontinuing the stimulant due to side effects, starting a wake-promoting agent, uptitrating narcolepsy therapy, continuing the SSRI, and referral for iron infusion. Safety precautions were emphasized, including avoiding driving or heavy machinery, risks near water, heights, or fire, and parasomnia measures such as securing doors and objects. Mood support was provided through psychiatry and psychology follow-up, school accommodations were recommended, and OSA/PLMs were addressed via ferritin monitoring. Conclusion This case demonstrates RSWA as a supportive finding in pediatric narcolepsy with cataplexy, often alongside PLMs and short REM latency, emphasizing comprehensive PSG review. Integrated management, including pharmacologic adjustments, safety education, and multidisciplinary referrals, optimizes outcomes. It highlights the need for tailored approaches in young patients to mitigate diagnostic pitfalls and long-term risks. Support (if any)