Liver involvement in ANCA-associated vasculitis

The aim of the study was to investigate the incidence, the clinical course and outcome of liver involvement and autoimmune hepatic diseases in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Liver function tests (LFT) (i.e. aspartate and alanine aminotransferase [AST, ALT], gamma-glutamyl transpeptidase [gamma-GT], alkaline phosphatase [ALP] and total bilirubin) were analysed at disease onset in therapy-naïve patients and during remission in patients with granulomatosis with polyangiitis (GPA, n = 67), microscopic polyangiitis (MPA, n = 28) and eosinophilic granulomatosis with polyangiitis (EGPA, n = 14). Results were correlated to the Birmingham Vasculitis Activity Score version 3 (BVAS v.3). Also, serologic tests for other autoimmune hepatic diseases were performed in these patients. During the active state, LFT abnormalities could be detected in 54 AAV patients (49.4 %). ALT, gamma-GT and ALP were significantly higher in GPA patients compared to MPA or EGPA patients at disease onset (p < 0.05). Increased values for gamma-GT in GPA patients correlated with the BVAS (p < 0.01) and were associated with pulmonary involvement, pulmonary-renal syndrome and a longer time to remission. Increased LFT in GPA patients decreased subsequently towards normal levels after initiation of therapy (p < 0.01). No case of severe liver involvement or autoimmune hepatic liver diseases was found in AAV patients. Liver involvement was mainly restricted to GPA patients, is associated with the disease activity and indicates a poorer outcome in patients with GPA. Progressive liver involvement or autoimmune hepatic diseases were not observed.