Measurement of serum C-reactive protein concentration for discriminating between suppurative arthritis and osteoarthritis in dogs

Abstract

BackgroundIn a dog with joint pain, it is important to determine whether it has suppurative joint disease, characterized by exudation of neutrophils in the synovial fluid, or not, as this affects choice of diagnostic tests and treatments. The aim of this study was to evaluate whether measurement of serum C-reactive protein (CRP) concentration could be used to discriminate between dogs with suppurative arthritis and osteoarthritis (OA). Furthermore, the concentrations of serum and synovial fluid interleukin (IL) 6 concentrations were measured in dogs with joint disease and in healthy dogs, and were correlated to serum CRP concentrations.MethodsDogs with joint pain were enrolled prospectively and were classified to have suppurative arthritis or OA based on synovial fluid analysis and radiographic/arthroscopic findings. Healthy Beagles were enrolled as a comparative group. CRP and IL-6 concentrations were measured with canine-specific immunoassays. The performance of CRP concentration in discriminating between dogs with suppurative arthritis and OA was evaluated using a previously established clinical decision limit for CRP (20 mg/l), and by receiver operator characteristic (ROC) curve and logistic regression analysis. Comparisons of CRP and IL-6 concentrations between groups were performed using t-tests, and correlations by Spearman rank correlation coefficients.ResultsSamples were obtained from 31 dogs with suppurative arthritis, 34 dogs with OA, and 17 healthy dogs. Sixty-two out of 65 dogs with joint disease were correctly classified using the clinical decision limit for CRP. Evaluation of ROC curve and regression analysis indicated that serum CRP concentrations could discriminate between suppurative arthritis and OA. Dogs with suppurative arthritis had higher serum CRP and serum and synovial fluid IL-6 concentrations compared to dogs with OA (p < 0.001). Dogs with OA had higher synovial fluid IL-6 concentrations (p < 0.001), but not higher serum CRP (p = 0.29) or serum IL-6 (p = 0.07) concentrations, compared to healthy dogs. There was a positive correlation between synovial fluid IL-6 and serum CRP concentrations (rs = 0.733, p < 0.001), and between serum IL-6 and serum CRP concentrations (rs = 0.729, p < 0.001).ConclusionCRP concentration was found to discriminate well between dogs with suppurative arthritis and OA.

Serum C-reactive protein concentrations in Nova Scotia Duck Tolling Retrievers with immune-mediated rheumatic disease

“…It is also possible that these dogs suffered from disorders other than, or in addition to, IMRD that induced systemic inflammation, with resulting high CRP concentrations. The CRP concentrations in these two dogs were of similar magnitude as those reported in other studies of immune-meditated polyarthritis [11, 15, 16]. In a study by Hillström et al [16], CRP was measured with the same assay as here and the median CRP concentration in dogs with immune-mediated arthritis was 118.0 mg/L, which is considerably higher than the medians in the present study.…”

“…The CRP concentrations in these two dogs were of similar magnitude as those reported in other studies of immune-meditated polyarthritis [11, 15, 16]. In a study by Hillström et al [16], CRP was measured with the same assay as here and the median CRP concentration in dogs with immune-mediated arthritis was 118.0 mg/L, which is considerably higher than the medians in the present study. Unfortunately, direct comparison of CRP concentrations between other studies is not feasible because of the lack of standardization of CRP measurements.…”

“…This resembles the CRP alterations in human SLE, where the CRP concentrations are often mildly elevated, but can also be low in individual patients with active disease [13]. In most of the IMRD dogs, the increase in CRP concentration was less than in immune-mediated polyarthritis in other dog breeds [11, 15, 16], but higher than concentrations reported for e.g., canine osteoarthritis [22]. A CRP of 20 mg/L has previously been established at our laboratory as the decision limit for clinical diagnosis of systemic inflammation.…”

Clinical utility of currently available biomarkers in inflammatory enteropathies of dogs

“…C‐reactive protein is a positive type II acute phase protein expressed in the liver69 in response to infection, inflammation, or cancer,70 and the serum CRP concentration is a nonspecific marker of inflammation 71, 72, 73, 74, 75, 76, 77, 78, 79, 80. Quantification of canine CRP in serum can be done using several assay formats,81, 82, 83, 84, 85, 86, 87, 88 all of which have a reference interval of approximately 0–8 mg/L.…”

The Effect of Routine Therapy Alone and Combined with Hyperbaric Oxygen Treatment on Prognostic Factors in Dogs with Acute Pancreatitis

“…C-reactive protein (CRP) is one of acute phase proteins and being a marker for several diseases (Christensen et al, 2015;Hillström et al, 2016;Bremer et al, 2017;Severo et al, 2018). When the inflammatory cells are activated by different inflammatory stimuli, the acute phase response is triggered and different cytokines are released from the inflammatory cell (Hillström et al, 2015;Gommeren et al, 2018).…”