Wernicke’s encephalopathy precipitated by neuromyelitis optica spectrum disorder and Graves’ disease: A tale of clinical and radiological dilemmas

Background: Neuromyelitis optica spectrum disorder (NMOSD), an autoimmune astrocytopathy, may share common clinico-radiological features with Wernicke's encephalopathy (WE). A variant of NMOSD, known as area postrema syndrome (APS), that presents with intractable hiccups and associated vomiting, might lead to the depletion of nutrients if not detected and treated early. Autoimmune thyroid disorders (i.e., Graves’ disease) may be associated with NMOSD. Rarely, thyrotoxicosis can give rise to thiamine depletion and WE. Case presentation: Here, we present a case of untreated hyperthyroidism in an Indian female who presented with thyrotoxicosis and later developed WE, possibly also contributed by NMOSD (APS)-induced recurrent vomiting. The patient recovered with antithyroid drugs, parenteral thiamine, and immunomodulatory therapy. The possible pathogenic mechanisms have been discussed. Conclusion: Our case establishes the importance of considering NMOSD variants in metabolic encephalopathy, especially if neuroimaging is suggestive and in the backdrop of another autoimmune disorder.