# Adequate diagnosis of the cause of Parkinsonism and treatment in an elderly patient with schizophrenia: A case report

## TL;DR

This case report highlights the importance of accurate diagnosis of parkinsonism in elderly schizophrenia patients, as treatment with levodopa improved both motor and emotional symptoms.

## Contribution

The case demonstrates that parkinsonism in schizophrenia can be levodopa-responsive Parkinson's syndrome, not just drug-induced.

## Key findings

- Levodopa treatment improved both motor and emotional symptoms in a patient with schizophrenia and parkinsonism.
- Nuclear medicine testing helped confirm a diagnosis of levodopa-responsive Parkinson's syndrome.
- Misdiagnosis of parkinsonism as negative symptoms can delay effective treatment.

## Abstract

Parkinsonism is frequently observed in patients with schizophrenia, and most patients are diagnosed with drug‐induced parkinsonism. However, comorbidity with idiopathic Parkinson's disease or Parkinson‐plus syndrome is also possible. The pathophysiology and treatment for each of these are entirely different, thus an appropriate diagnosis is required. However, distinguishing them based on clinical symptoms alone is often difficult, and many cases are misdiagnosed. Additionally, Parkinsonism is frequently mistaken for negative symptoms.

We report a case of 68‐year‐old woman diagnosed with schizophrenia, who was admitted to a welfare center. At approximately age 60, the patient experienced motivation reduction, a loss of appetite, and pain in the extremities. In her mid‐60s, tremor and muscle rigidity appeared; nuclear medicine testing was performed for a detailed examination, resulting in a diagnosis of levodopa‐responsive Parkinson's syndrome. Notably, the patient's parkinsonism and emotional symptoms, which had been considered negative symptoms thus far, improved with levodopa treatment.

This case report illustrates the importance of properly diagnosing the cause of parkinsonism in patients with schizophrenia.

A 68‐year‐old female with schizophrenia presented with parkinsonism in her mid‐60s. Based on the course of the disease and physical examination, drug‐induced parkinsonism was unlikely, and a nuclear medicine examination was performed, resulting in a diagnosis of levodopa‐responsive Parkinson's syndrome. Treatment with levodopa improved not only motor symptoms but also emotional symptoms, which had been considered negative symptoms.