Abstract
Neuromyelitis optica (NMO or Devic's syndrome) is a rare demyelinating disease of the CNS that predominantly affects the spinal cord and optic nerves and shares many clinical and radiological features with multiple sclerosis (MS). The association of NMO with autoimmune thyroiditis has been reported very rarely. Early differentiation between NMO and MS is very important because they have different natural courses and treatment regimens. We report a case regarding a 53-year-old woman who was admitted initially with hiccups and paraesthesias, but was not evaluated during first two episodes and presented with severe progression of NMO. Patient was found to have autoimmune thyroiditis with lymphocytic infiltration of thyroid which progressed to hypothyroidism. NMO was diagnosed with seropositivity for NMO-IgG and longitudinally extensive spinal cord lesions (three or more spinal segments). Patient poorly responded to treatment due to the lack of early diagnosis and aggressive immunosuppressant therapy.