Posterior reversible encephalopathy syndrome and stroke after intravenous immunoglobulin treatment in Miller-Fisher syndrome/Bickerstaff brain stem encephalitis overlap syndrome.

The association of a posterior reversible encephalopathy syndrome (PRES) without arterial hypertension with autoimmune-mediated inflammatory neuropathies such as Guillain-Barré syndrome (GBS) is a rare and poorly understood phenomenon. To date, PRES has been described as initial manifestation, coincidental finding, or adverse event subsequent to immunomodulatory treatment with intravenous immunoglobulin (IVIG) in cases of axonal and demyelinating GBS as well as in Miller-Fisher syndrome (MFS). We here report a case of MFS/Bickerstaff brain stem encephalitis (BBE)-overlap syndrome and nonhypertensive PRES that occurred in close temporal association with IVIG treatment and caused stroke. Immunoadsorption ameliorated the disease course. Our case supports the notion that in severe cases, immunoadsorption should be considered as first-line therapy instead of IVIG for rapid removal of IgG and thus to hasten recovery and improve functional outcome.