The widespread adoption of advanced vascular imaging in clinical practice has revealed issues with the classification criteria for vasculitis currently endorsed by the ACR, altering the understanding of giant cell arteritis and changing diagnostic methods. Given these changes, researchers have worked to revise the classification criteria for giant cell arteritis and Takayasu’s arteritis, which were adopted in 1990.
At the ACR clinical practice session Updated Classification Criteria for Large-Vessel Vasculitis, three experts will review the rationale for revising and discuss the methods used to develop the proposed criteria. The session will take place from 4:30 – 6:00 pm on Tuesday in Room W375b.
Cristina Ponte, MD, a rheumatologist at Hospital de Santa Maria, Lisbon, Portugal, will discuss the giant cell arteritis proposed classification criteria. She will review the new criteria as well as the methodology used to develop them.
“The previous classification criteria for large vessel vasculitis were established before modern vascular imaging modalities were used,” she said. “We know now that giant cell arteritis is no longer a disease confined to the cranial arteries and that imaging has a crucial role in the diagnosis and assessment of disease extent. In addition, some angiographic patterns of disease involvement in Takayasu’s arteritis resemble the ones found in giant cell arteritis, which poses a great challenge to clinicians to correctly differentiate between these two diseases.”
Dr. Ponte said that the proposed classification criteria are a result of the largest-ever international study in vasculitis, the Diagnostic and Classification Criteria in Vasculitis Study (DCVAS). DCVAS included data from about 6,500 patients from more than 130 sites.
Dr. Ponte, who has worked on several vasculitis research projects, including DCVAS, will illustrate during her lecture why imaging is crucial for diagnosing and classifying large-vessel vasculitis. She will focus on the various imaging modalities available, their findings, and patterns of disease distribution.
Peter C. Grayson, MD, MSc, an investigator at the National Institutes of Health, Bethesda, MD, will review proposed classification criteria for Takayasu’s arteritis, including the methodology used to develop the proposed criteria.
“Clinical research in large-vessel vasculitis is expanding with the recent success of a few key, randomized clinical trials,” Dr. Grayson said. “It’s important to update the classification criteria for these diseases, as interest in these conditions is at an all-time high. We’re hopeful new criteria will enable the next wave of successful clinical trials in these diseases where new therapeutics are greatly needed. Accurate classification criteria are important, as they enable researchers to study a particular condition and set the standard for how to identify a patient with a typical form of a certain disease.”
Echoing Dr. Ponte, Dr. Grayson, who is head of the Vasculitis Translational Research Program at the National Institute of Arthritis and Musculoskeletal and Skin Diseases, said the evidence shows a need for the proposed update to the classification criteria.
“Our group has published a few papers about why we need to update criteria in vasculitis,” he said. “We’ve shown that the performance characteristics of the 1990 criteria for Takayasu’s arteritis and giant cell arteritis have declined throughout the years as physicians are recognizing newer aspects of these illnesses.”
Ravi Suppiah, MD, MBChB, PGDipSportMed, a private practice rheumatologist in Auckland, New Zealand, will present the lecture “The Changing Face of Large-Vessel Vasculitis.” Dr. Suppiah will review the differences between the existing classification criteria and the recently drafted criteria.
“I’ll show how changes in imaging have informed our understanding of these entities and how they may relate to classification,” he said. “For example, ultrasound of temporal arteries and axillary arteries have enabled diagnosis of giant cell arteritis based on symptoms and imaging alone without need for biopsy. MRI, MRA, CT angiograms, and PET-CT are now routinely used in the diagnostic process of large-vessel vasculitis. Using these non-invasive modalities has shown us that the aorta and branches are involved in both Takayasu’s arteritis and giant cell arteritis.”
Dr. Suppiah will also explore questions relating to increased use of imaging and the information that has yielded.
“Are Takayasu’s arteritis and giant cell arteritis different spectrums of the same disease? Does age change the phenotype? How does age influence the decision on classification? How do biopsy results influence classification?” he said.
Given the limited proven therapeutic options for giant cell arteritis and Takayasu’s arteritis and the resurgence of research in this area, Dr. Suppiah said, it’s important to have effective classification criteria.
“Large-vessel vasculitis is relatively rare,” he said. “The new criteria will allow researchers to enroll patients with large vessel involvement based on imaging, rather than just cranial ischemic symptoms and positive biopsy. This may enable easier recruitment into trials.”