Parkinsonism-hyperpyrexia Syndrome After Amantadine Withdrawal: Case Report and Review of the Literature.

ABSTRACT

INTRODUCTION: Parkinsonism-hyperpyrexia syndrome (PHS) is a rare and potentially fatal complication of Parkinson disease (PD) characterized by a neuroleptic malignant-like syndrome due to abrupt discontinuation of antiparkinsonian medications. CASE REPORT A 79-year-old woman with late-stage PD presented at the hospital with neuropsychiatric and uncontrolled parkinsonian motor symptoms. Soon after the abrupt discontinuation of amantadine, the patient suddenly presented with global rigidity, global unresponsiveness, diaphoresis, tachycardia, recurrent hyperpyrexia, and a mildly elevated creatine kinase, which lead to the diagnosis of PHS. Amantadine was then reinitiated and her symptoms resolved within 10 days. CONCLUSIONS: Amantadine is an antiparkinsonian medication scarcely associated with PHS. The few reported cases are further summarized and discussed in this article. This case highlights the importance of early recognition of PHS, which may be caused by changes in other antiparkinson agents such as amantadine, and the need to slowly titrate such agents.