Factors affecting relapse in patients with Granulomatosis Polyangiitis: a single-center retrospective cohort study

Background and aim: This study aimed to determine the frequency of relapse, the risk factors for relapse, and the correlation of relapse with immunosuppressive regimens in patients with granulomatosis polyangiitis (GPA). Materials and methods: The demographic characteristics, the clinical, laboratory, and radiological findings, the immunosuppressive treatment regimens, and the remission and relapse rates of 50 patients with GPA were obtained retrospectively from medical records. Results: The mean relapse-free survival rates at years 1, 3, and 5 were 82%, 60%, and 50%, respectively. Increased relapse rates were observed in patients who had cavitary lung lesions (52.2% vs. 22.2%, p = 0.04) and in those who had elevated serum creatinine levels (1.8 vs. 0.9, p = 0.00). The patients received two different types of remission induction therapies; 36% of them received the combination therapy involving cyclophosphamide (CYC) and rituximab (RTX), and 62% received CYC alone. Relapse was observed in 22.3% of the patients who received the combination remission induction therapy and in 61.3% of the patients who received CYC alone (P = 0.003). Conclusion: An increased risk of relapse was observed in patients who had cavitary lung lesions and in those who had elevated serum creatinine levels. The combined use of RTX and CYC for the remission therapy in GPA reduced the relapse rates compared with the use of CYC alone.