# Respiratory Acidosis as a Diagnostic Clue in Symptomatic Epilepsy With Stroke Mimics: A Case Report

## TL;DR

A case report shows that respiratory acidosis can help diagnose epilepsy mistaken for stroke, highlighting its importance in differential diagnosis.

## Contribution

The paper highlights respiratory acidosis as a novel diagnostic clue for symptomatic epilepsy mimicking stroke.

## Key findings

- Respiratory acidosis was observed in a patient with stroke-like symptoms and later diagnosed with symptomatic epilepsy.
- Administration of diazepam improved symptoms, confirming seizure-related issues.
- Unexplained respiratory acidosis in stroke mimics may indicate underlying epilepsy.

## Abstract

Stroke mimics are difficult to differentiate from each other. Symptomatic epilepsy can also occur, but it is necessary to perform a magnetic resonance imaging (MRI) scan to distinguish it from a stroke. Although respiratory acidosis has been reported to occur with partial-onset seizures due to prolonged apnea, respiratory acidosis is rarely suspected to be a sign of epilepsy. We report a case in which respiratory acidosis helped to diagnose symptomatic epilepsy with stroke mimics. The patient was a 52-year-old female who was brought to the emergency room with the chief complaint of difficulty in talking. When she visited the hospital, sensory aphasia was observed, and a computed tomography (CT) scan was performed. She vomited after the CT scan, and an arterial blood gas analysis showed a pH of 7.26 with a PaCO2 level of 71 mmHg, indicating respiratory acidosis. After the administration of diazepam, the seizures abated and her sensory aphasia improved. Later, an investigation of the patient’s history revealed symptomatic epilepsy and discontinuation of antiepileptic drugs. If unexplained respiratory acidosis is noted in a patient with stroke mimics, a further investigation of the patient’s history and physical examination may help to diagnose symptomatic epilepsy.