Session Information
Date: Sunday, November 13, 2016
Title: Vasculitis - Poster I: Large Vessel Vasculitis and Polymyalgia Rheumatica
Session Type: ACR Poster Session A
Session Time: 9:00AM-11:00AM
Background/Purpose: Histological findings of intima-media or transmural inflammation in temporal artery biopsies (TABs) have undisputed high value for diagnosis of giant cell arteritis (GCA). Conversely, the diagnostic significance of isolated adventitial or periadventitial cell infiltrates (e.g., inflammation limited to the adventitia [ILA], vasa vasorum vasculitis [VVV], and small vessel vasculitis [SVV]) remains unclear. We investigated the diagnostic value of isolated ILA, VVV or SVV in TABs for GCA and for the combined GCA/polymyalgia rheumatica (GCA/PMR) spectrum because of the close clinical connection of GCA and PMR.
Methods: All TABs performed in a single center over 7 years (2009–2015) were independently reviewed by 2 experienced pathologists blinded to the clinical diagnoses and with particular attention to isolated (peri)adventitial cell infiltrates. VVV was defined as a perivascular infiltrate within or in close contact with the adventitia and SVV as infiltrates of a periadventitial vessel. Medical charts were reviewed and diagnoses were classified as GCA, PMR and other by the final clinical diagnosis, with a follow-up of at least 6 months, as the gold standard. For TABs that did not show a classical histological picture of GCA with intima-media or transmural inflammation, we calculated the specificity and positive predictive value (PPV) of ILA, VVV or SVV for GCA and for GCA/PMR diagnoses. These variables were calculated for findings observed by at least 1 or by both pathologists. Cohen’s kappa statistics were used to measure inter-observer agreement.
Results: We analyzed TABs for 100 patients; 6 were discarded because they did not allow for proper morphologic analysis of all vessel layers and 19 had classical histological features of GCA. For the remaining 75 TABs (mean age of patients, 69±12 years, 59% female), the diagnosis was GCA (n=8), PMR (n=7) and non-GCA/PMR (n=60). The frequency of (peri)adventitial TAB findings and their respective specificities and PPV for clinical diagnosis of GCA or GCA/PMR are in the Table. Inter-observer agreement was good for ILA (kappa 0.63 [95% CI 0.42–0.84]) and fair for SVV (0.31 [95% CI 0.09–0.52]) and VVV (0.21 [95% CI -0.01–0.43]).
|
GCA (n=8) vs. non-GCA (n=67) |
GCA/PMR (n=15) vs. non-GCA/PMR (n=60) |
|||||
|
Frequency |
Spec (95% CI) |
PPV (95% CI) |
Frequency |
Spec (95% CI) |
PPV (95% CI) |
|
| ILA |
|
|
|
|
|
|
| At least 1 reader |
2/8 vs. 10/67 |
85% (74–93) |
17% (2–48) |
4/15 vs. 8/60 |
87% (75–94) |
33% (10–65) |
| Both readers |
1/8 vs. 5/67 |
93%(84–96) |
17% (0–64) |
1/15 vs. 5/60 |
92% (82–97) |
17% (0–64) |
| VVV |
|
|
|
|
|
|
| At least 1 reader |
0/8 vs. 7/67 |
90% (80–96) |
0% (0–41) |
0/15 vs. 7/60 |
88% (77–95) |
0% (0–41) |
| Both readers |
0/8 vs. 1/67 |
99% (92–100) |
0% (0–98) |
0/15 vs. 1/60 |
98% (91–100) |
0% (0–98) |
| SVV |
|
|
|
|
|
|
| At least 1 reader |
2/8 vs. 27/67 |
60% (47–72) |
7% (1–23) |
7/15 vs. 22/60 |
63% (50–75) |
24% (10–44) |
| Both readers |
1/8 vs. 8/67 |
88% (78–95) |
11% (0–48) |
4/15 vs. 5/60 |
92% (82–97) |
44% (14–79) |
| ILA: isolated inflammation of the adventitia, PPV: positive predictive value, Spec: specificity, SVV: small vessel vasculitis, VVV: vasa vasorum vasculitis | ||||||
Conclusion: Isolated (peri)adventitial infiltrates in a TAB do not reliably predict a diagnosis of GCA and should not be considered relevant GCA-defining histological criteria. More general consensus is needed on the histological criteria defining GCA.
To cite this abstract in AMA style:
Le Pendu C, Meignin V, Gonzalez-Chiappe S, Galateau-Sallé F, Mahr A. Poor Predictive Value of Isolated Adventitial and Periadventitial Infiltrates in Temporal Artery Biopsies for Diagnosis of Giant Cell Arteritis [abstract]. Arthritis Rheumatol. 2016; 68 (suppl 10). https://acrabstracts.org/abstract/poor-predictive-value-of-isolated-adventitial-and-periadventitial-infiltrates-in-temporal-artery-biopsies-for-diagnosis-of-giant-cell-arteritis/. Accessed .« Back to 2016 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/poor-predictive-value-of-isolated-adventitial-and-periadventitial-infiltrates-in-temporal-artery-biopsies-for-diagnosis-of-giant-cell-arteritis/