American Board of Internal Medicine (ABIM) Certification Practice Exam

What condition can occur in hospitalized patients with Parkinson's disease after sudden withdrawal of dopaminergic medications?

1. Serotonin syndrome

2. Parkinsonian-hyperpyrexia syndrome

3. Neuroleptic malignant syndrome

4. Delirium tremens

The correct answer is: Parkinsonian-hyperpyrexia syndrome

The condition that can occur in hospitalized patients with Parkinson's disease after sudden withdrawal of dopaminergic medications is Parkinsonian-hyperpyrexia syndrome. This syndrome is characterized by a severe increase in muscle rigidity, hyperthermia, autonomic dysfunction, altered mental status, and sometimes elevated creatine phosphokinase levels. It is essentially a severe manifestation of parkinsonism that results from the abrupt cessation of dopaminergic therapy in patients who are reliant on these medications to manage their symptoms. The underlying mechanism involves a sudden decrease in dopaminergic activity, leading to an exacerbation of Parkinsonian symptoms and the potential for complications such as fever and severe rigidity. This condition underscores the importance of carefully managing the withdrawal of dopaminergic medications in patients with Parkinson's disease, particularly in a hospitalized setting where medication administration may be altered. In contrast, serotonin syndrome primarily results from excessive serotonergic activity in the brain, which is not typically related to the withdrawal of dopaminergic medications. Neuroleptic malignant syndrome occurs in response to antipsychotic medications, and delirium tremens is related to alcohol withdrawal, neither of which are the direct products of withdrawal from dopaminergic therapy in Parkinson's disease.