Case report: A previously healthy 60-year-old woman presented to the dermatology clinic for a deep phenol peeling. A few minutes after the procedure, she had become confused and disoriented, so the neurology clinic was called. On the neurological assessment, the patient kept asking her sister where she was and how she got to the hospital. It was noted that the patient had deep anterograde amnesia and retrograde amnesia ranging from a few hours before the arrival at the hospital, with preserved episodic and semantic memories. The remainder of the neurologic exam was normal. She was submitted to basic laboratory evaluation, which showed no abnormalities. Brain magnetic resonance imagin showed a mild FLAIR (Fluid-Attenuated Inversion Recovery) hyperintensity on the left medial temporal lobe, without signal alterations in the DWI (diffusion-weighted imaging) image. After about 4 hours of the onset, the disorientation had resolved and she was discharged after 24 hours of observation, asymptomatic. Discussion: Phenol peeling is the most aggressive of all peels, and as this substance is absorbed by the skin, metabolized by the liver, and excreted by urine it is associated with systemic complications, such as cardiac arrhythmias and acute kidney injury. There are no previous reports of the occurrence of a transient global amnesia (TGA) episode after such a procedure, although it is known that it can be precipitated by physical exertion and psychological stress. The pathophysiology of a TGA episode is thought to be related to metabolic stress to the CA-1 subfield of the hippocampus. Although the association is unclear, we can make an assumption that phenol could have a disruptive metabolic effect on this particular brain area. Conclusion: We report a case of TGA preceded by a deep phenol peeling. Although it is impossible to establish causality in this case, it is important that the neurologist be aware that certain medical conditions, procedures and substance administration can be associated with TGA.

Case report: A 57-year-old woman was referred to our service after noticing difficulty in coordinating the movements of the right hand. The symptoms occurred after she consumed ayahuasca in a religious ceremony and persisted after the psychedelic effects weaned off. On the first evaluation, she had right hemiataxia and increased blood pressure (200/100 mmHg). The head computed tomography (CT) scan revealed a left basal ganglia hemorrhage. No abnormalities were found on CT angiography. The patient later reported that a few years earlier, she was diagnosed with a hemorrhagic stroke at another hospital, which also happened within a few hours of ayahuasca intake. However, she has not stopped using it monthly since then. Discussion: Ayahuasca is a potent plant-based hallucinogenic brew used traditionally for spiritual and medicinal purposes. The substance responsible for its effects is Dimethyltryptamine (DMT), which is known to be a potent serotonin receptor agonist, especially the 5HT2A. This substance may induce an acute raise in blood pressure and consequently trigger a hemorrhagic stroke. To this date, there are no cases reported of hemorrhagic stroke after using this drug. Conclusion: Although ayahuasca has been associated with spiritual and therapeutic benefits, its potential risks should not be ignored, including serious complications, such as hemorrhagic stroke.

We report the case of a healthy 25-year-old man presenting with sudden onset dizziness, strabismus, and cloudy vision that improved when he closed one of his eyes. He denied pain with eye movement or color desaturation, as well as history of recent immunization or febrile illness. He did not present any other neurologic symptom, but he affirmed having had a limited episode of a discrete strabismus four months before. In his first assessment at the emergency room his neurologic examination revealed a 30° exotropia of the right eye on the primary gaze position along with adduction deficit and abduction nystagmus bilaterally on conjugated horizontal eye movement, characterizing an internuclear ophthalmoplegia on both eyes. He also presented with asymmetrical convergence deficit, with inability on completing adduction on his right eye. On the vertical upward gaze there was also a vertical nystagmus. Eye fundus examination did not show retinal and optic nerve alterations. Visual acuity was normal. This set of findings qualified a WEBINO (wall-eyed bilateral internuclear ophthalmoplegia). During investigation, lumbar puncture showed mild hyperproteinrachia, with absence of oligoclonal bands and normal CSF (cerebrospinal fluid GigG (immunoglobulin G) index. He was submitted to a course of pulse therapy with methylprednisolone. Neuroaxis magnetic resonance imaging evidenced a demyelinating periaqueductal lesion, involving medium longitudinal fasciculus, ponto-mesencephalic junction and mesencephalic tegmentum, without gadolinium enhancement. As he remained symptomatic, plasmapheresis was indicated, with complete remission of symptoms afterwards. Following his investigation the tests for both anti-aquaporin-4 and anti-MOG antibodies were negative, and until the conclusion of this report, a diagnosis of clinical isolated syndrome remained as the main hypothesis.

Rupture of the left ventricular wall after mitral valve replacement is an infrequent but lethal complication. Reporting correction technique of ventricular rupture with bovine pericardium patch secured with glue and without suturing: a 51 years-old female patient, with double rheumatic mitral lesion, severe stenosis and discrete insufficiency, who had a mitral valve replacement. During surgery, the patient presented a ventricular rupture of the posterior wall (atrioventricular disruption), which was successfully repaired using bovine pericardium with sutureless biological glue over the epicardium of the damaged area. Sixty months after surgery the patient has no symptoms.

Case report: A 31-year-old man was referred to our service after experiencing paresthesia, followed by distal weakness in both his feet and hands. These symptoms occurred 20 days after the administration of the fourth dose of the ChAdOx-1 COVID vaccine. A lumbar puncture was performed, which showed remarkably thick cerebrospinal fluid (CSF). Biochemical analysis of the CSF revealed 920 mg/dL of protein and a white cell count of 7.3/mm3 . An electromyography (EMG) was performed, which was compatible with the diagnosis of Guillain-Barré Syndrome (GBS). The patient was treated with intravenous immune globulin and showed clinical improvement. One month later, he experienced a recurrence of symptoms and underwent a new EMG, which again showed motor nerve conduction blocks. A new lumbar puncture was performed, and a thick fluid was obtained, with a protein concentration of 804 mg/dL. CSF flow blockage was suspected and the patient underwent a suboccipital puncture, which showed a more watery CSF, with a protein concentration of 227 mg/dL. A spinal magnetic resonance was performed, revealing an arachnoid web at the T3–T4 level. GBS relapse was presumed and the patient was treated with five sessions of therapeutic apheresis, which improved his strength and sensory symptoms. Discussion: Blockage of CSF circulation at the spinal level can produce fluid with abnormally high levels of protein, which in this case was a confounding factor during the clinical investigation. Conclusion: We report a case of concurrent GBS and spinal block, which led to abnormally high CSF protein levels during lumbar puncture, causing diagnostic ambiguity during the investigation.