[Secondary restless legs syndrome]

Restless legs syndrome (RLS) is known to occur secondary to various medical conditions such as iron deficiency, pregnancy, end-stage renal disease, and neuropathy. Secondary RLS usually occurs later in the life and in the absence of a family history of RLS. Diagnosis of secondary RLS may be difficult, particularly in patients with neurological comorbidities. Sensory disturbance due to neurological disorder may mimic the symptoms of RLS symptom. In distinguishing between RLS and RLS mimics, neurophysiological findings, in addition to a detailed neurological examination, are helpful. Treatment of secondary RLS often requires management of the background medical condition. Iron supplementation is useful in patients with iron deficiency. Dopamine agonists are usually effective for both primary and secondary RLS; however, an increased dose of dopamine agonist may be necessary in some secondary RLS cases, particularly in uremic RLS. In patients with end-stage renal disease on hemodialysis, management of daytime symptoms, particularly during the hemodialysis sessions, may be necessary. Secondary RLS is still an unrecognized and underdiagnosed disorder. Medical practitioners should be aware of comorbid RLS in patients with neurological conditions that could be the cause of RLS.