Anton syndrome in posterior reversible encephalopathy syndrome followed by Guillain-Barré syndrome: A case report

Background and aims: Anton-Babinski syndrome is a rare condition due to occipital injury by different mechanisms, such as vasogenic edema in posterior reversible encephalopathy syndrome (PRES) resulting from bood-brain barrier (BBB) disruption. PRES has been rarely associated with Guillain-Barre syndrome (GBS). It has hypothesized that autonomic dysfunction in GBS might lead to BBB damage with consequent PRES before motor symptom onset. Another possibility is that BBB injury in PRES might trigger immune-mediated reaction leading to GBS. Methods: An 80-year-old woman was admitted to our emergency room (ER) after she developed two partial seizures, successfully treated with 5mg of intravenous midazolam. Her medical history was unremarkable except for previous SARS-CoV-2 disease. Results: After one hour from midazolam administration, the patient was still markedly confused. Examination revealed binocular blindness, without signs of optic neuropathy;despite being obviously blind, she denied any vision disturbance, a phenomenon known as visual anosognosia. Her blood pressure was 180/90mmHg. Brain MRI showed posterior alterations compatible with PRES. She was treated with antihypertensive and vision recovered after 24 hours. On day 3, she developed areflexia and proximal symmetrical weakness to both upper and lower limbs. Electromyography suggested recent motor poliradiculoneuropathy. Clinical picture was compatible with GBS and intravenous immunoglobulins were started, with gradual recovery. A 8-day follow-up MRI showed nearly complete normalization of posterior lesions. Figure 1 Conclusion: Anton syndrome is a possible rare presentation of PRES. Occurrence of unexplained weakness after PRES should raise suspicion of GBS in consideration of their pathophysiologic connection.