Hypophysitis in granulomatosis with polyangiitis: rare presentation of a multisystem disease

Granulomatosis with polyangiitis (GPA) is a type of granulomatous vasculitis that can involve any organ in the body. The pituitary gland is one of the uncommon sites to be involved in this condition, with only a few cases reported in the literature. Our patient initially presented with central diabetes insipidus, epistaxis and haematuria. Diagnosis was established by antineutrophil cytoplasmic antibodies (cANCA) positivity against a background of typical clinical features and a bulky pituitary on magnetic resonance imaging (MRI) scan. Patient was started on steroids and methotrexate which were later changed to mycophenolate mofetil due to intolerance. Due to the refractory nature of the disease the patient was treated with one course of rituximab. Since then she has not had epistaxis, joint pains or haematuria. She continues to have diabetes insipidus although the requirement of desmopressin has come down. We thus report a case of GPA with hypophysitis which is one of the rare manifestations of the disease.