Polyglandular autoimmune syndrome disguised as mental illness

Our case acts to highlight the numerous presentations of polyglandular autoimmune syndromes. A 62-year-old Taiwanese woman with a history of schizophrenia presented to our emergency department with a brain tumour causing her headaches. She was admitted due to severe anaemia, and after further investigation, the patient was discovered to have pernicious anaemia and autoimmune thyroiditis-consistent with the diagnosis of polyglandular autoimmune syndrome IIIb. Her underlying primary psychiatric diagnosis was then questioned. The diagnosis of her endocrinopathies were likely delayed for many years due to the psychiatric disorder which may have been due to her long-standing autoimmune hypothyroidism and/or vitamin B12 deficiency. Initial treatment brought about major behavioural improvement, and encourages physicians to investigate secondary causes of psychosis and other coexisting autoimmune diseases when a patient presents with one endocrinopathy.