PULMONARY FIBROSIS IN RENAL ANTI-NEUTROPHIL CYTOPLASMIC ANTIBODY (ANCA) ASSOCIATED VASCULITIS IN TASMANIA OVER A 10 YEAR PERIOD

S KUO¹, PG TAN², A GRAVER¹, S YEW¹, R YU¹, L JEFFS¹, MD JOSE^1.3, M MATHEW⁴, R RAJ⁴, D COOKE⁴, G KIRKLAND¹

¹Renal Unit, Royal Hobart Hospital, Tasmania; ²Renal Unit, Monash Medical Centre, Melbourne, Victoria; ³School of Medicine, University of Tasmania; ⁴Renal Unit, Launceston General Hospital, Tasmania

Aim: To determine if pulmonary fibrosis associated with ANCA-associated vasculitis (AAV) is a significant clinical problem in Tasmanian patients diagnosed with Renal AAV.

Background: Pulmonary fibrosis, a well recognised condition with limited treatment options, has been associated with AAV in medical literature. To our knowledge, it has not been reported in Australian populations.

Methods: We conducted a retrospective, exploratory study using a state-wide renal biopsy database and identified all Tasmanians newly diagnosed with pauci-immune crescentic glomerulonephritis between 2004 and 2013. Clinical details were collected from medical records. Presence of pulmonary fibrosis was defined as typical computed tomography scan findings of pulmonary fibrosis and/or diagnosis by a respiratory physician.

Results: Preliminary data from this time period identified 60 patients who were newly diagnosed with pauci-immune glomerulonephritis, of whom 6 (10%) (median age 69, 67% male) were diagnosed with pulmonary fibrosis. 5 patients (83%) were MPO positive and 1 patient (17%) was PR3 positive. 2 patients were diagnosed with pulmonary fibrosis 12 months before the renal AAV diagnosis, 1 had concurrent diagnosis and 2 were diagnosed after. No statistically significance difference in clinical outcome was found between the two cohorts. 2 of the patients with pulmonary fibrosis had a symptomatic and objective improvement in lung function with azathioprine treatment.

Conclusions: This retrospective study suggests that pulmonary fibrosis associated with renal AAV is a relatively common problem in the Tasmanian population. Further, larger studies would be required to delineate its clinical significance. Immunosuppressive treatment may be of respiratory benefit in these patients.