A case of NMO presenting with hyperthyroidism

Abstract

Neuromyelitis optica (NMO) is an autoimmune disease of central nervous system with extensive clinical presentations but based on the international consensus diagnostic criteria 2015. The horizon has broadened to a larger entity called NMOSD or NMO spectrum disorders. Nonneurological systemic autoimmune diseases especially thyroid disorders are commonly associated with NMOSD, among which Hashimoto’s thyroiditis is common, whereas not much literature is available regarding the association of Graves’ disease with NMOSD. A 38-year-old male presented with acute onset upper motor neuron quadriparesis along with features of hyperthyroidism with a prior history of sudden onset bilateral decreased vision of both eyes 3 years back. Magnetic resonance imaging (MRI) showed T2 hyperintensity involving cervicodorsal cord from C4 to D6 indicating a longitudinally extensive transverse myelitis (LETM) but brain MRI was normal. Serum antiaquaporin 4 antibody in the cell-based assay was positive. Serum thyroid stimulating hormone was very low with high free T4 and positive thyroid stimulating hormone receptor antibody and anti-thyroid peroxidase Ab. With optic neuritis, transverse myelitis (LETM), and positive antiaquaporin 4 antibody, he was diagnosed with NMO with Graves’ disease. Autoimmune thyroid diseases are associated with NMO in many studies but precise clinical and serological quantification of thyroid disorders especially Graves’ disease is still lacking. We are presenting a case of NMO with Graves’ disease who presented with symptoms of hyperthyroidism before myelitis. Our patient developed myelitis almost 3 years after having optic neuritis, but before myelitis, he was having symptoms of hyperthyroidism. Hence, patients of suspected NMO must be monitored for other nonneurological autoimmune diseases both clinically and serologically even in early stage when they are not fulfilling the diagnostic criteria.