title: Validation and application of a canine-specific automated high-sensitivity C-reactive protein assay.
abstract: Measurement of low concentrations of C-reactive protein (CRP) in dogs has previously been performed with nonautomated assays. The aim of this study was to validate an automated high-sensitivity CRP (hsCRP) assay, developed by modifying a routinely used canine-specific immunoturbidimetric CRP test (cCRP). Imprecision, linearity under dilution, limit of blank (LOB), limit of detection (LOD), and limit of quantification (LOQ) were determined for the hsCRP test, as well as the presence of prozone effect and interferences. The imprecision, measured as intra-assay variation, was ≤2.7%. The assay was acceptably linear under dilution. An analytically relevant prozone effect was present for samples with CRP concentration >150 mg/L, and there were mild interferences from hemolysis and lipemia. The LOB, LOD, and LOQ were 0.10 mg/L, 0.22 mg/L, and 0.50 mg/L, respectively. A method comparison study with a canine-specific enzyme-linked immunosorbent assay (ELISA) was performed, showing poor agreement between the hsCRP test and the ELISA. An additional aim of the study was to apply the hsCRP test to clinical research samples. Serum samples from 7 dogs undergoing ovariohysterectomy were collected pre- and postoperatively, and CRP was measured with both the cCRP and hsCRP assay. The expected postoperative increase in CRP was detected earlier with the hsCRP test, compared with the cCRP test. The hsCRP assay was further applied on samples from 6 lean and 9 overweight dogs. There was no significant difference in CRP concentration between the groups (P = 0.06). In conclusion, the hsCRP test had acceptable analytical performance, and the assay was successfully applied to clinical research samples.
authors.affiliation: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden (Hillström, Hagman, Häggström, Ljungvall)Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden (Söder)Translational Haemophilia Pharmacology, Novo Nordisk, Maaloev, Denmark (Kjelgaard-Hansen) anna.hillstrom@slu.se.
authors.forename: Anna
authors.initials: A
authors.lastname: Hillström
authors.affiliation: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden (Hillström, Hagman, Häggström, Ljungvall)Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden (Söder)Translational Haemophilia Pharmacology, Novo Nordisk, Maaloev, Denmark (Kjelgaard-Hansen).
authors.forename: Ragnvi
authors.initials: R
authors.lastname: Hagman
authors.affiliation: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden (Hillström, Hagman, Häggström, Ljungvall)Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden (Söder)Translational Haemophilia Pharmacology, Novo Nordisk, Maaloev, Denmark (Kjelgaard-Hansen).
authors.forename: Josefin
authors.initials: J
authors.lastname: Söder
authors.affiliation: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden (Hillström, Hagman, Häggström, Ljungvall)Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden (Söder)Translational Haemophilia Pharmacology, Novo Nordisk, Maaloev, Denmark (Kjelgaard-Hansen).
authors.forename: Jens
authors.initials: J
authors.lastname: Häggström
authors.affiliation: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden (Hillström, Hagman, Häggström, Ljungvall)Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden (Söder)Translational Haemophilia Pharmacology, Novo Nordisk, Maaloev, Denmark (Kjelgaard-Hansen).
authors.forename: Ingrid
authors.initials: I
authors.lastname: Ljungvall
authors.affiliation: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden (Hillström, Hagman, Häggström, Ljungvall)Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden (Söder)Translational Haemophilia Pharmacology, Novo Nordisk, Maaloev, Denmark (Kjelgaard-Hansen).
authors.forename: Mads
authors.initials: M
authors.lastname: Kjelgaard-Hansen
mesh_terms: D000818:Animals; D002097:C-Reactive Protein / Q000378:metabolism*; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D007249:Inflammation / Q000175:diagnosis / Q000662:veterinary*; D057230:Limit of Detection; D008297:Male; D009391:Nephelometry and Turbidimetry / Q000662:veterinary; D015203:Reproducibility of Results
chemical_list: D002097:C-Reactive Protein
keywords: C-reactive protein; dogs; method comparison; obesity; validation