Introduction: Eosinophilic granulomatosis with polyangiitis (EGPA) symptoms vary widely depending on the affected organ and time from onset.It is crucial to investigate the distinct clinical characteristics of EGPA in patients with either MPO-ANCA positivity or negativity, as well as the relationship between MPO-ANCA titers and kidney function and prognosis, although these areas remain insufficiently studied.Methods: We conducted a retrospective analysis of 55 patients diagnosed with EGPA who visited the Department of Immunology and Collagen Disease and the Department of Nephrology at Kyoto University between 2005 and 2024.First, we examined the characteristics of organ involvement (kidney, lung, paranasal sinus, heart, nerve, skin) in MPO-ANCA-positive and negative EGPA patients.Next, we examined the relationship between MPO-ANCA titer and the kidney lesions (hematuria, proteinuria and AKI) and the number of years between initial symptoms and EGPA diagnosis.Third, we examined the kidney prognosis of all EGPA patients.Results: Kidney lesions were significantly more common in MPO-ANCA-positive patients (52.4%) compared to MPO-ANCA-negative patients (14.7%) (p<0.01).Additionally, ear and nasopharyngeal lesions tended to be more frequent in MPO-ANCA-positive patients, whereas cardiac lesions tended to be more commonly observed in MPO-ANCA-negative patients.Among MPO-ANCA-positive patients, no correlation was observed between MPO-ANCA titer and the presence of hematuria, proteinuria and AKI, or the duration between the onset of initial symptoms and the diagnosis of EGPA.After treatment, 83.3% of patients with hematuria and 66.7% of patients with proteinuria achieved complete remission.In contrast, patients with AKI did not return to their baseline kidney function, although they exhibited improvement.Conclusion: Our findings suggest that clinical features differ between MPO-ANCA-positive and negative EGPA cases.Notably, the incidence of kidney complications is higher in MPO-ANCA-positive EGPA cases compared to MPO-ANCA-negative cases.However, the severity and onset of kidney lesions cannot be predicted by the MPO-ANCA titer.Generally, the kidney prognosis of EGPA is good, however in some cases they can be severe and appear a long time after the initial lesions.Therefore, careful follow-up is required in EGPA cases.The content presented in this abstract was submitted for Kidney Week 2025.I have no potential conflict of interest to disclose.I did not use generative AI and AI-assisted technologies in the writing process.
Tran et al. (Wed,) studied this question.