Year: 2020
Type: letter
Abstract: Thank you for the opportunity to address the points made by Drs. Watson et al on our recent case of immunoglobulin G4-related disease (IgG4-RD) in a dog. We agree that development of diagnostic criteria of IgG4-RD in dogs deserves attention, should be based on evaluation of a broad case set, and should involve a consensus opinion from multiple clinicians and researchers, as was done in human medicine.1 We look forward to being part of that conversation. The consensus comprehensive diagnostic criteria for IgG4-RD in humans involve a combination of (1) characteristic diffuse/localized swelling or masses in single or multiple organs; (2) increased serum IgG4 concentrations (>135 mg/dL); and (3) histopathologic examination with (3.1) marked lymphocyte and plasmacyte infiltration and fibrosis, (3.2) infiltration of IgG4+ plasma cells: ratio of IgG4+/IgG+ cells >40% and >10 IgG4+ plasma cells/high-power field (HPF), or (3.3) both.1 Specific combinations of these findings lead to a more certain diagnosis and not all lesions are expected to have every finding.1, 2 Our published work addresses these criteria with open discussion of both the strengths and weaknesses of our assertion that our case is consistent with the diagnosis of IgG4-RD. It is not surprising that differences are present between our dog with IgG4-RD and English Cocker Spaniels with chronic pancreatitis. Both phenotyping studies of IgG4-RD in humans segregated the pancreatic predominant disease phenotype from other phenotypes and documented distinct differences of signalment, risk factors, clinical findings, and clinical progression between phenotypes.3, 4 The observations provided by Dr Watson et al are very useful as they suggest that a similar breadth of presentations may be found in dogs with IgG4-RD. We expect that their in-review manuscript lays out data from English Cocker Spaniels with chronic pancreatitis fully and provides useful information on the pancreatic predominant phenotype of IgG4-RD in the dog. Rigorous comparison of our dog with IgG4-RD with chronic pancreatitis cases in dogs with IgG4-RD should be delayed until a full evaluation of that data can be made. We find IgG4-RD in humans a fascinating disease and are intrigued by the potential that it shares as diverse a presentation in dogs as it does in humans. We expect that as awareness of this disease process increases, more cases will be described and further clarification of the diagnostic criteria for IgG4-RD in dogs will be possible.
DOI: 10.1111/jvim.15733
Authors: A. Russell Moore, Lydia J. Colopy, Kai-Biu Shiu, Laura A. Snyder, Anne C. Avery, Emily D. Rout
Institution: Colorado State University
Language: English
Subfield: Rheumatology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,804
OpenAlex ID: W3006818145