Pituitary Dysfunction in Granulomatosis With Polyangiitis: The Mayo Clinic Experience

Context: Pituitary involvement in granulomatosis with polyangiitis (GPA) has been described in case reports. The aim of this study was to describe the clinical presentation and outcomes of pituitary disease in patients with GPA evaluated at a tertiary referral center. Setting: A retrospective review of patients with GPA-related pituitary disease seen at the Mayo Clinic in Rochester, Minnesota. Patients: A total of 637 patients with antineutrophil cytoplasmic antibodies-associated vasculitis were followed at our institution from 1996 through 2011. Eight patients (1.3%) with clinically confirmed pituitary involvement formed the basis of this study. Interventions: None. Measurements: Pituitary function was assessed with hormonal testing, including TSH, free T-4, cortisol, ACTH, prolactin, FSH, LH, estradiol, T, IGF-1, and simultaneous serum and urine osmolalities. Results: Secondary hypogonadism and diabetes insipidus were the predominant manifestations of pituitary disease (87.5 and 75% of patients, respectively). All patients had abnormal pituitary imaging. A sellar mass with central cystic change and peripheral enhancement was the commonest imaging finding. Pituitary disease was managed with glucocorticoids in combination with cyclophosphamide or rituximab, achieving disease remission in all but one patient. However, permanent anterior pituitary dysfunction was noted in 63% of the patients. Diabetes insipidus was more often reversible, with resolution in 66.7% of the patients. Conclusions: Pituitary involvement in GPA is rare, but it needs to be recognized to avoid unnecessary biopsies of sellar lesions encountered in the context of GPA, and to minimize the risk of irreversible pituitary function loss by prompt implementation of definitive medical therapy for the vasculitis.