Background:
Acute motor and sensory axonal neuropathy, a variant of Guillan Barre Syndrome, is within a spectrum of neuromuscular disorders that typically follows an infectious period, however, rarely can also follow other proinflammatory conditions including injury and vaccinations. Variants affecting the brainstem can lead to loss of brainstem reflexes with diffuse loss of motor function, mimicking brain death.
Design/Methods:
Here we present the case of a 63-year-old male with history of cardiac disease admitted to the ICU after a bicycle collision with head strike and loss of consciousness with extensive facial and musculoskeletal injuries in addition to a diffuse subarachnoid hemorrhage. His exam worsened throughout his admission to go from intact brainstem reflexes and spontaneous movement of all his extremities to flaccidity of his right upper extremity. He continued to have ventilator dependence resulting in tracheostomy and PEG placement. The morning after his procedure, neurology was consulted for an exam that appeared to mimic brain death; only a left corneal reflex and hyporeflexia of bilateral upper extremities remained intact, but even these disappeared over the coming few days. EEG demonstrated moderate encephalopathy only, and MRI did not demonstrate hypoxic injury. EMG showed severe sensorimotor axonal polyneuropathy. GQ1b, GD1b, and GM1 antibodies were all unremarkable. IVIG was trialed, but eventually family decided to proceed with comfort measures.
Conclusions:
This case is illustrates the importance of a broad differential of patients in the ICU that do lose brainstem reflexes as it can be secondary to AMSAN or other subtypes of GBS. Central causes of weakness are often immediately explored, but peripheral nervous system causes are generally not immediately considered in these cases. It allows for an additional differential in the presentation of acute onset of weakness within an ICU setting.