Restless Legs Syndrome (RLS) & Periodic Limb Movement Disorder (PLMD)

Key Features

• Frequency in children is about 2%

• Etiology of these disorders is unknown, but there has been some association with iron deficiency

Clinical Findings

• RLS is associated with an uncomfortable sensation in the lower extremities that occurs at night when trying to fall asleep, is relieved by movement, and is sometimes described by children as "creepy-crawly" or "itchy bones"

• PLMD is stereotyped, repetitive limb movements often associated with a partial arousal or awakening

Diagnosis

• A diagnosis of RLS is generally made by history and a diagnosis of PLMD can be made with a sleep study

• Caffeine, nicotine, antidepressants, and other drugs have been associated with RLS and PLMD

• Medical evaluation includes obtaining a serum ferritin and C-reactive protein (CRP) level

Treatment

• If the CRP is normal and the ferritin is < 50 mg/dL, treatment with ferrous sulfate should be considered