Delusions of infestation during delirium in a patient with restless legs syndrome.

A case is described in which delusions of infestation developed during delirium secondary to pneumonia in a patient with restless legs syndrome (RLS). This case demonstrates how tactile sensations may precede and give rise to delusional misinterpretations. Since RLS is relatively common in elderly people and may be due to a treatable cause such as iron deficiency, it is worth considering this syndrome in patients with delusions of infestation.