Impact of different ANCA serotypes on the long-term outcome of ANCA-associated vasculitis patients

Abstract

Objectives

To investigate the clinical features and long-term outcomes of Chinese anti-neutrophil cytoplasmic antibodies (ANCAs)-associated vasculitis (AAV) patients with different ANCA serotypes.

Methods

Two hundred and twenty-four AAV patients from January 2010 to June 2021 were divided into myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA groups. Clinical and long-term outcomes were compared.

Results

In this study, the average follow-up was 46.4 months (range 0.3–188.4 months). One hundred and seventy-seven (79.0%) patients were MPO–ANCA-positive and 47 were PR3–ANCA-positive; the mean age of MPO–ANCA positive patients at diagnosis was elder than that of PR3–ANCA positive patients (67.0 vs. 60.0 years, p = .004). Among PR3–ANCA-positive patients, ear, nose and throat symptoms were more common (p = .014). Between two ANCA serotypes, there were no differences in complement 3 (C3), Birmingham vasculitis activity score (BVAS), five-factor score (FFS) or other organ involvements. For all AAV patients, the overall survival rates at one, three and five years were 80.0%, 67.0% and 56.4%, respectively. The cumulative relapse-free rates of one, three and five years were 89.5%, 76.4% and 68.4%, respectively. The survival of AAV patients was unaffected by the ANCA serotype (p = .23). The ANCA serotype also had no effect on either disease relapse (p = .20) or remission rates (p = .10). In our study, PR3–ANCA patients showed a better long-term survival, as the 5-year survival rate and the 5-year relapse-free survival rate of PR3–ANCA patients were 60.7% and 76.9%, while that of MPO–ANCA patients were 55.2% and 65.8%, respectively. Rather than ANCA serotype, younger patients with milder kidney involvement and lower disease assessment scores (BVAS and FFS) might be more relevant to better prognosis.

Conclusions

The likelihood of induced remission, patient survival or disease recurrence is all unaffected by ANCA serotypes. A better prognosis is seen in younger patients with milder kidney involvement and lower BVAS/FFS scores.

Keywords:

• Anti-neutrophil cytoplasmic antibodies
• vasculitis
• long-term follow-up
• survival
• relapse

Acknowledgements

Not applicable.

Author contributions

FQ: study conception and design, statistical analyses and writing of manuscript. JH: study conception and design, writing of manuscript. WW: study conception and design. All authors read and revised manuscript. All authors approved the final manuscript.

Ethical approval

Ethics approval was granted by the Tianjin Medical University General Hospital Ethics Committees (IRB2021-YX-001-01), and the study was conducted in accordance with the Declaration of Helsinki.

Consent form

Informed consent was not required because of the retrospective study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Requests for data should be directed to the senior author but will be conditioned on the legal premises under which they were collected.

Additional information

Funding

This work is funded by the National Natural Science Foundation of China (81903934) and Tianjin Health Science and Technology Project (ZC20205).