Paraparesis as the First Manifestation of Myocarditis Due to Cardiac Embolization into the Aorta Mimicking Guillain-Barré Syndrome: A Case Report

Guillain-Barré syndrome (GBS) is the most common cause of acute flaccid paralysis, which is characterized by ascending, rapid-onset, symmetrical limb weakness and sensory disturbances that are typically established 3-6 weeks after an antecedent infection, usually an upper respiratory tract infection.

We present the case of a 19-year-old man who was acutely admitted to the emergency room due to the sudden onset and gradual worsening of symmetrical lower extremity paresis, sensory disturbance, and pain occurring 3 weeks after an upper respiratory tract infection.GBS was the initial diagnosis. However, this was ruled out after thorough neurological examination due to the rapid progression of neurological deficiency, intense pain, and the absence of a pulse in the lower extremity arteries. CT angiography revealed occlusion of the abdominal aorta, and an intracardiac thrombus was detected. The myocarditis complicated by intracardiac thrombus formation and subsequent embolization into the aorta was finally concluded as the actual reason for the patients' complaints, initially mimicking GBS.

This case report highlights a rare combination of two distinct, life-threatening conditions that together mimicked Guillain-Barré syndrome. The initial physical examination played a crucial role in establishing the correct differential diagnosis.