Dear Editor,In their interesting case report, Ramakrishan et al described a patient with Guillain-Barre syndrome (GBS) who developed vision loss during the course of the illness and proved later to have posterior reversible encephalopathy syndrome (PRES).[1] Herein, the following two comments regarding that case report can be made.First, PRES is a clinical condition characterized by sudden systemic hypertension associated with headache, seizure, visual disturbance, and altered mental state. The authors mentioned that GBS with dysautonomia can be considered as an independent risk factor for the development of various clinical manifestations of PRES (such as visual disturbance) through which an acute increase in blood pressure results in the release of pro-inflammatory cytokines to break the blood-brain barrier and cause vasogenic edema.[1] Such explanation cannot be applied to the current case as the patient had no documented persistent hypertension. Actually, the association of PRES without arterial hypertension with autoimmune-mediated inflammatory neuropathies such as GBS is a rare and poorly understood phenomenon. There might be another mechanism contributing to the development of PRES in this GBS patient. The authors mentioned that the patient received intravenous immunoglobulin (IVIG) 20 g/day for 5 days. On day 14 after admission, the patient had two attacks of generalized seizures to be associated later with severe vision loss in both eyes.[1] To date, various reports have described PRES as an adverse event subsequent to immunomodulatory treatment with IVIG in cases of axonal and demyelinating GBS.[234] The exact mechanism is not fully understood. Hence, in severe GBS cases, immunoadsorption has been advocated as the first-line therapy instead of IVIG for rapid removal of IgG to hasten recovery, improve functional outcome, and minimize serious aftermaths.[4]Second, the authors stated that PRES can occur concurrently with weakness or during the course of GBS.[1] It should be noted that PRES preceding the development of GBS has previously been reported.[5]