Background/Purpose: Pituitary involvement in granulomatosis with polyangiitis (GPA) is rare with an incidence of approximately 1%. Objectives were: (1) Describe ten new cases of pituitary involvement in GPA seen at Canadian healthcare institutions; (2) Perform a literature review of pituitary involvement in GPA and compare previously reported cases with our series.

Methods: We surveyed members of the Canadian Vasculitis Research Network (CanVasc; 18 centers across Canada) for patients with GPA and pituitary disease. Cases were defined based on: (1) Clinical characteristics consistent with GPA; (2) Pituitary MRI/pituitary histology consistent with GPA, with or without hormonal dysfunction; (3) Exclusion of alternative causes of pituitary disease. Clinical details were collected using a standardized record form. We performed a literature search of the following databases: Medline, Embase, Scopus, and Proquest, using “granulomatosis with polyangiitis” and “pituitary” as keywords.

Results:

Our case series included 10 patients (9 female, 1 male). Mean age at GPA diagnosis and presentation of pituitary disease were: 33.8 years (range 13 to 56) and 35.3 years (range 18 to 56), respectively. Five patients presented with pituitary disease at GPA diagnosis; mean time from GPA to pituitary disease diagnosis was 3.4 years for the remaining five. Nine patients were ANCA positive (PR3 for 8, MPO for 1). Diabetes insipidus (DI) was the most frequent hormonal dysfunction observed (n = 8). Hypogonadism and central hypothyroidism were seen in 3 and 2 patients, respectively. Pituitary hormone testing was normal in 2 patients (presenting with pituitary mass only). All patients had GPA involvement at other sites including ENT (n = 8), pulmonary (n = 6), and renal (n = 4). Eight patients received therapy including glucocorticoids alone (n = 1), with IV cyclophosphamide (CYC, n = 2), oral CYC (n = 3) or rituximab (n = 1), or a combination of mycophenolate mofetil and tacrolimus (n = 1). All patients had systemic disease remission on follow-up. Hormonal deficiencies were persistent after treatment in all patients with pituitary dysfunction at baseline. Our literature review yielded 67 other cases of pituitary involvement in GPA. The largest series included 9 patients. A limitation of our series, and previous case reports, is the lack of pituitary histology to definitively exclude an alternative cause for pituitary disease arising concurrently with GPA. Tissue is rarely obtained unless there is a surgical indication (e.g. compression of the optic chiasm) or a diagnostic dilemma exists, such as in isolated pituitary GPA.

Conclusion: This new and large case series of pituitary disease and GPA, together with previously reported cases, suggest: (1) Pituitary disease may be diagnosed concurrent to systemic GPA or later; (2) Pituitary disease is rarely isolated; (3) Posterior pituitary dysfunction is the most common disease manifestation; (4) Pituitary disease does not seem to negatively impact the global prognosis; (5) Pituitary dysfunction and need for hormone supplementation are often irreversible.

« Back to 2017 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/pituitary-disease-and-granulomatosis-with-polyangiitis-a-collaborative-canadian-case-series-and-review-of-the-literature/