Pituitary dysfunction in granulomatosis with polyangiitis

Purpose: Granulomatosis with polyangiitis (GPA) is a multisystem disease, characterized by necrotizing small-vessel vasculitis, which mainly affects the respiratory tract and the kidneys. Pituitary involvement in GPA is rare, present in about 1% of all cases of GPA. To date, only case reports or small case series have been published. Herein we report clinical features, imaging findings, treatment and outcomes in three patients with GPA-related pituitary dysfunction (PD). Methods: A retrospective analysis of three cases of GPA-related PD was conducted, followed by systematic review of the English medical literature using PubMed. Results: The three cases include three women aged between 32 and 37 years. PD was the presenting feature in one and two developed PD in the course of the disease. All patients had a pituitary lesion on MRI. Conventional treatment with high doses of glucocorticoids and cyclophosphamide led to resolution or improvement of the MRI abnormalities, whereas it was not effective in restoring PD. A systematic review identified 51 additional patients, showing that GPA can lead to partial or global PD, either at onset or, during the course of the disease. Secondary hypogonadism is the predominant manifestation, followed by diabetes insipidus (DI). Sellar mass with central cystic lesion is the most frequent radiological finding. Conclusion: GPA should be carefully considered in patients with a sellar mass and unusual clinical presentation with DI and systemic disease. Although conventional induction-remission treatment improves systemic symptoms and radiological pituitary abnormalities, hormonal deficiencies persist in most of the patients. Therefore, follow-up should include both imaging and pituitary function assessment.