Fibroblast Growth Factor 23 in Feline Chronic Kidney Disease

• Published in: Journal of veterinary internal medicine 2013-03, Vol.27 (2), p.234-241
• Main Authors: Geddes, R.F., Finch, N.C., Elliott, J., Syme, H.M.
• Format: Article
• Language: English
• Subjects: Animals; Azotemia; Cat; Cat Diseases - blood; Cats; Creatinine - blood; Cross-Sectional Studies; Enzyme-Linked Immunosorbent Assay - methods; Enzyme-Linked Immunosorbent Assay - veterinary; Female; Fibroblast Growth Factors - blood; Fibroblasts; Growth factors; Homeostasis; Hyperparathyroidism; Hyperparathyroidism, Secondary - blood; Hyperparathyroidism, Secondary - veterinary; Hypotheses; Kidney diseases; Limit of Detection; Male; Metabolism; Parathyroid Hormone - blood; Pathogenesis; Phosphate; Phosphates - blood; PTH; Reference Values; Renal Insufficiency, Chronic - blood; Renal Insufficiency, Chronic - veterinary; Reproducibility of Results; Retrospective Studies; Rickets; Statistics, Nonparametric; Vitamin D
• ISSN: 0891-6640; 1939-1676
• DOI: 10.1111/jvim.12044

Background Fibroblast growth factor 23 (FGF‐23) is a phosphaturic hormone involved in the pathogenesis of secondary renal hyperparathyroidism (SRHP) in humans. There are no published studies examining feline FGF‐23. Objectives Validation of a method for FGF‐23 quantification in feline plasma and assessment of the associations among plasma FGF‐23, PTH, creatinine, and phosphate concentrations in cats with chronic kidney disease (CKD). Animals One hundred nonazotemic and azotemic geriatric (>9 years) client‐owned cats. Methods Retrospective cross‐sectional study: Cats were categorized into 4 groups: control group (plasma creatinine (Cr) ≤2.0 mg/dL), stage 2 (Cr 2.1–2.8 mg/dL), stage 3 (Cr 2.9–5.0 mg/dL), stage 4 (Cr >5.0 mg/dL). Stages 2 and 3 were further subdivided based on International Renal Interest Society targets for plasma phosphate concentration (PO4): stage 2a (PO4 ≤4.5 mg/dL), stage 2b (PO4 >4.5 mg/dL), stage 3a (PO4 ≤5 mg/dL), stage 3b (PO4 >5 mg/dL). Plasma FGF‐23 concentrations were measured by a human intact FGF‐23 ELISA. Descriptive statistics and linear regression were performed. Results The ELISA demonstrated acceptable precision, reproducibility, and specificity. Plasma FGF‐23 concentrations increased with increasing plasma creatinine concentrations and were significantly different between all groups (P