Spontaneous Remission of Encephalopathy Associated with Autoimmune Thyroid Disease in a Patient with Grave's Disease: A Rare Occurrence in a Rare Clinical Picture

Encephalopathy associated with autoimmune thyroid disease (EAATD) is a rare condition that may occur in patients with an autoimmune thyroid disease. The clinical presentation of EAATD is characterized by a variety of neurological and/or psychiatric alterations and can show up with focal signs secondary to stroke-like events or generalized symptoms. From a nosological, epidemiological, and diagnostic point of view, EAATD still remains a controversial disorder. Indeed, a widely accepted definition of EAATD has not yet been established, and the diagnosis of this condition is often difficult because of the heterogeneous clinical presentation, the number of possible non-specific manifestations, and poorly defined diagnostic criteria. These factors may inevitably affect the exact estimation of the prevalence of EAATD. From a clinical perspective, the course of EAATD is variable and ranges from response, often dramatic and rapid, to corticosteroids to no or partial response and requirement of other immunosuppressive treatments. Occasionally, spontaneous remission or adverse outcomes have also been reported. Here, we describe the case of a 52-year-old woman who presented with right facial and upper limb numbness and perioral tingling. The laboratory, radiological, and electrophysiological investigations revealed no relevant abnormalities from a neurological point of view. The investigations carried out during hospital admission incidentally disclosed a clinical picture compatible with Graves’ disease, including elevated levels of antithyroid antibodies. However, the cause of her stroke-like episode remained unclear, and the reported symptoms disappeared spontaneously in approximately 10 days. Finally, EAATD characterized by the spontaneous remission of the symptoms was diagnosed, and the patient did not show any relapse or reoccurrence of EAATD thereafter. This intriguing case allows us to focus on and discuss some of the most debatable aspects of EAATD, including its definition, diagnosis, and management.