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Willis-Ekbom disease/restless legs syndrome (WED/RLS) seems to be a frequent cause of intractable chronic insomnia (ICI) but is under-recognized in children/adolescents with neurodevelopmental conditions (NDCs), as many patients do not have the ability to express the underlying "urge-to-move". In light of this, we aim to develop a protocol for behavioral observations supporting the diagnosis of WED/RLS. We investigated 26 pediatric patients (age 1-16 years, median 8) with NDCs, ICI and evidence of familial WED/RLS employing (1) "emplotted narratives" for description of the various "urge-to-move" presentations and (2) self-description and "behavioral observations" during a "suggested clinical immobilization test" (SCIT). Parental narratives reflected typical WED/RLS-related "urge-to-move" symptoms during day-, bed-, and nighttime in all patients. Fifteen out of 26 patients could describe the "urge-to-move" during the SCIT. Ten out of 26 patients, unable to describe their symptoms due to cognitive disabilities, showed patterns of "relieving-movements" upon observation. Sensory processing abnormalities were reported in all patients, with tactile sensitivities (26/26) (including shifted pain threshold) as the most common sensory domain. "Emplotted narratives" and structured "behavioral observations" support recognition of familial WED/RLS associated movement patterns and provide a useful tool for the diagnosis of WED/RLS in children with NDCs in a clinical office setting.
Willis-Ekbom disease is also known as?