ACR Meeting Abstracts

ACR Meeting Abstracts

  • Meetings
    • ACR Convergence 2024
    • ACR Convergence 2023
    • 2023 ACR/ARP PRSYM
    • ACR Convergence 2022
    • ACR Convergence 2021
    • ACR Convergence 2020
    • 2020 ACR/ARP PRSYM
    • 2019 ACR/ARP Annual Meeting
    • 2018-2009 Meetings
    • Download Abstracts
  • Keyword Index
  • Advanced Search
  • Your Favorites
    • Favorites
    • Login
    • View and print all favorites
    • Clear all your favorites
  • ACR Meetings

Abstract Number: 102

Implications of Positive Tests for ANCA in a Pediatric Population

Karen James1, Peter Merkel 2 and Aimee Hersh 3, 1University of Utah, 84113, Utah, 2University of Pennsylvania, Philadelphia, 3University of Utah Primary Children's Hospital, Salt Lake City

Meeting: 2020 Pediatric Rheumatology Symposium

Keywords: ANCA, inflammatory bowel disease (IBD), Pediatric rheumatology, test, Vasculitis

  • Tweet
  • Click to email a link to a friend (Opens in new window) Email
  • Click to print (Opens in new window) Print
Session Information

The 2020 Pediatric Rheumatology Symposium, originally scheduled for April 29 – May 2, was postponed due to COVID-19; therefore, abstracts were not presented as scheduled.

Date: Friday, May 1, 2020

Title: Poster Session 2

Session Type: ACR Abstract Session

Session Time: 5:00PM-6:00PM

Background/Purpose: Testing for ANCA, particularly performed by ELISA (anti-MPO/PR3) is highly sensitive and specific for ANCA-associated vasculitis (AAV). However ANCA testing may be used in clinical scenarios with low likelihoods for AAV, leading to a decreased positive predictive value. While non-AAV diagnoses associated with positive testing for ANCA in adult populations have been reported, clinical scenarios in children leading to testing for ANCA testing in children are likely different. This study characterized the diagnoses and outcomes associated with positive tests for ANCA in children.

Methods: Retrospective cohort study of all testing of ANCA performed in pediatric patients (≤18 years old) in a single healthcare system (mixed academic and non-academic) representing over 2/3 of the healthcare in the state from 2004-2017. Chart data was extracted on patients who were positive on their first test for ANCA by IIF or ELISA. Patient positive for ANCA were divided into three groups: 1. AAV; 2. Autoimmune gastrointestinal disease (inflammatory bowel disease (IBD) Crohn’s disease, Ulcerative colitis (UC), undifferentiated IBD, autoimmune hepatitis (AIH), and primary sclerosing cholangitis (PSC); 3. Other diagnoses/No diagnosis. Follow-up time was defined as time from initial ANCA testing to time of last available visit.

Results: Testing for ANCA was performed on 2,931 patients, of whom 154 (5.3%) were positive for ANCA by IIF and/or ELISA. There was an increase in testing of ANCA from 2004 to 2016 (p=0.027). Of 154 subjects positive for ANCA, all were tested by IIF and 64 (41%) were tested by ELISA. 153/154 (99%) were positive by IIF and 37/64 (58%) were positive by ELISA. 24 (16%) patients received a diagnosis of AAV, 1 was diagnosed with UC < 1 year from time of her diagnosis of AAV (pANCA/PR3+), and 1 had a preceding diagnosis of AIH (pANCA/MPO+). 62 (40%) received a diagnosis of IBD, 19 of whom had concurrent AIH or PSC, and 14 with AIH/PSC without IBD. 56 (36%) of patients positive for ANCA did not have a diagnosis of AAV or autoimmune GI disease. ANCA type and diagnosis category are shown in Table 1. 7/76 (9%) of patients with autoimmune GI disease had a positive ANCA by ELISA. 20/33 (61%) GI and 14/30 (47%) with other diagnoses who were c or pANCA positive had a titer of > 1:80. The diagnoses of the patients without AAV or GI disease are shown in Table 2.

All but 2 patients with AAV were diagnosed within 6 weeks of the initial testing for ANCA; 2 were diagnosed later, after seeking second opinion. No other patients who were positive for ANCA and not initially diagnosed with AAV (n=130) subsequently developed AAV, with a median of 4.7 years of follow up (IQR 2.4, 10.3).

Conclusion: The majority of positive tests for ANCA occurring in children are associated with diseases other than AAV, especially IBD, AIH, and PSC. Positive tests for ANCA occur in a variety of autoimmune and infectious diseases in children, even at moderate to high titers. The clinical importance of a positive test for ANCA in children without AAV is not clear; however, a positive test for ANCA in the absence of concurrent evidence of AAV does not appear to confer risk for later development of AAV.

Table 1. Positive Tests for ANCA by Assay Type and Diagnosis

Table 2. Diagnoses of Pediatric Patients Positive for ANCA


Disclosure: K. James, None; P. Merkel, Abbvie, 1, AstraZeneca, 1, 2, Biogen, 1, Boeringher-Inglehelheim, 1, 2, Bristol-Myers-Squibb, 1, 2, Celgene, 1, 2, ChemoCentryx, 1, 2, CSL Behring, 1, Genentech/Roche, 1, 2, Genzyme/Sanofi, 1, 2, GlaxoSmithKline, 1, 2, InflaRx, 1, 2, Insmed, 1, Jannsen, 1, Kiniksa, 1, Pfizer, 1, Sparrow, 1, Kypha, 1, TerumoBCT, 1, UpToDate, 1; A. Hersh, None.

To cite this abstract in AMA style:

James K, Merkel P, Hersh A. Implications of Positive Tests for ANCA in a Pediatric Population [abstract]. Arthritis Rheumatol. 2020; 72 (suppl 4). https://acrabstracts.org/abstract/implications-of-positive-tests-for-anca-in-a-pediatric-population/. Accessed .
  • Tweet
  • Click to email a link to a friend (Opens in new window) Email
  • Click to print (Opens in new window) Print

« Back to 2020 Pediatric Rheumatology Symposium

ACR Meeting Abstracts - https://acrabstracts.org/abstract/implications-of-positive-tests-for-anca-in-a-pediatric-population/

Advanced Search

Your Favorites

You can save and print a list of your favorite abstracts during your browser session by clicking the “Favorite” button at the bottom of any abstract. View your favorites »

All abstracts accepted to ACR Convergence are under media embargo once the ACR has notified presenters of their abstract’s acceptance. They may be presented at other meetings or published as manuscripts after this time but should not be discussed in non-scholarly venues or outlets. The following embargo policies are strictly enforced by the ACR.

Accepted abstracts are made available to the public online in advance of the meeting and are published in a special online supplement of our scientific journal, Arthritis & Rheumatology. Information contained in those abstracts may not be released until the abstracts appear online. In an exception to the media embargo, academic institutions, private organizations, and companies with products whose value may be influenced by information contained in an abstract may issue a press release to coincide with the availability of an ACR abstract on the ACR website. However, the ACR continues to require that information that goes beyond that contained in the abstract (e.g., discussion of the abstract done as part of editorial news coverage) is under media embargo until 10:00 AM ET on November 14, 2024. Journalists with access to embargoed information cannot release articles or editorial news coverage before this time. Editorial news coverage is considered original articles/videos developed by employed journalists to report facts, commentary, and subject matter expert quotes in a narrative form using a variety of sources (e.g., research, announcements, press releases, events, etc.).

Violation of this policy may result in the abstract being withdrawn from the meeting and other measures deemed appropriate. Authors are responsible for notifying colleagues, institutions, communications firms, and all other stakeholders related to the development or promotion of the abstract about this policy. If you have questions about the ACR abstract embargo policy, please contact ACR abstracts staff at [email protected].

Wiley

  • Online Journal
  • Privacy Policy
  • Permissions Policies
  • Cookie Preferences

© Copyright 2025 American College of Rheumatology