THE OFFICIAL NEWS SOURCE OF ACR CONVERGENCE 2022 • NOVEMBER 10-14



ANCA-associated vasculitis criteria revised

Recent advances in the field of vasculitis have exposed problems with the classification criteria that have been used for this group of diseases since 1990. To address the limitations of the criteria, the ACR has recently supported the development of new vasculitis classification criteria.

A preliminary draft of new criteria for ANCA-associated vasculitis will be discussed during the clinical symposium New Classification Criteria for ANCA-Associated Vasculitis: Implications for Clinical Practice from 7:30 – 9:00 am Tuesday. Several members of the steering committee responsible for overseeing the project will explain the need for revised classification criteria, highlight the changes to the classification criteria, and demonstrate how to apply the criteria appropriately.

The symposium will present new classification criteria for the three forms of ANCA-associated vasculitis: Granulomatosis
with polyangiitis, microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis.

suppiah
Ravi Suppiah, MBChB, MD, FRACP

Speaking on behalf of the committee, presenter Ravi Suppiah, MBChB, MD, FRACP, said it was important to update the classification criteria for vasculitis because the 1990 criteria are no longer consistent with current disease definitions.

“For example, microscopic polyangiitis, which is one of the major forms of ANCA-associated vasculitis, was not recognized in the previous criteria,” he said.

“In addition, tests for ANCA were not in routine use when the previous classification criteria were developed, and now
patients are more often identified earlier in their disease course. Furthermore, the use of advanced cross-sectional imaging, especially CT scans, has become routine compared to 30 years ago.”

In developing the new criteria, Dr. Suppiah, who will present the section of the session titled “New Classification Criteria for ANCA-Associated Vasculitis: Why and How?” said it was important to get the global vasculitis research community to help.

The ACR, the European League Against Rheumatism (EULAR), and the Vasculitis Foundation endorsed the project, and all
three organizations provided funding for the Diagnostic and Classification Criteria in Vasculitis Study (DCVAS). The study included more than 6,000 patients from about 130 sites worldwide.

“We collected detailed clinical, radiological, and laboratory information about each patient and their presenting illness, which was captured in an online database,” said Dr. Suppiah, who has worked on the DCVAS study since its inception when he was a fellow at the University of Oxford, England. “A vignette of each individual case was created and then reviewed by an independent expert. The expert was asked to make a diagnosis based on the information provided. If the expert came to the same diagnosis as the submitting physician, this was considered the reference diagnosis for that patient. If there was discrepancy, then that case was reviewed by another expert. A case was only included if two people concurred with the diagnosis.”

Several thousand data elements — clinical, radiological, and laboratory — were captured for each patient.

“This information was then reduced using statistical methods by excluding items where the prevalence was quite low or where there was no difference between the groups, and by combining items that made clinical sense. We then used a variety of standard and novel statistical approaches to develop the relevant criteria.”

The methodology used to establish classification criteria for other diseases such as rheumatoid arthritis or gout is not directly transferable. “Developing classification criteria for multiple different forms of vasculitis is complex,” Dr. Suppiah said. “We are dealing with several heterogeneous, multi-organ diseases rather than a single disorder. We also had to contend with the inherent circularity of defining the reference diagnosis as a starting point.”

To address these issues, researchers used a composite of several methodological approaches, including data-driven methods, expert opinion, and standard statistical methods such as multivariable regression.

Other investigators will also present lectures during the symposium, including Joanna Robson, BSc, PhD, MRCP, who is Consultant Senior Lecturer in Rheumatology and Faculty of Health and Applied Sciences at the University of the West of England, Bristol. Dr. Robson will compare the differences between the drafted 2016 criteria and the published 1990 criteria.

Raashid A. Luqmani, DM, FRCP, FRCPE, who is one of the three coprincipal investigators of the DCVAS study, will present “Clinical Implications of the 2016 Classification Criteria for ANCAAssociated Vasculitis.” He is Professor of Rheumatology and Consultant Rheumatologist, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Science, at the University of Oxford, Oxford, England.

Dr. Luqmani’s fellow co-principal investigators of the DCVAS study, Peter A. Merkel, MD, MPH, Chief of Rheumatology and Professor of Medicine and Epidemiology at the University of Pennsylvania in Philadelphia, and Richard A. Watts, MD, Senior Lecturer in Rheumatology at the University of East Anglia, Norwich, England, will also speak during the symposium.

Other speakers include investigators Peter Grayson, MD, PhD, who leads the Vasculitis Translational Research Program at the National Institutes of Health and co-chairs the American College of Rheumatology Criteria Subcommittee, and PhD candidate Cristina Ponte, MD, a rheumatologist at Hospital de Santa Maria, Lisbon, Portugal.

CLINICAL SCIENCE TRACK
New Classification Criteria for ANCA-Associated Vasculitis: Implications for Clinical Practice
7:30 – 9:00 am Tuesday • Ballroom A