Fibroblast growth factor 23 (FGF-23) concentrations in cats with early nonazotemic chronic kidney disease (CKD) and in healthy geriatric cats.
BACKGROUND
Fibroblast growth factor (FGF-23) has an important role in phosphate regulation. Its clinical relevance in cats with CKD has not been explored previously.


OBJECTIVE
The study objectives were (1) to determine whether FGF-23 concentrations are increased in nonazotemic cats, cats which developed azotemia within 12 months of screening compared with cats that remained non-azotemic, and (2) to evaluate the relationships between FGF-23 and PTH and FGF-23 and glomerular filtration rate (GFR).


METHODS
Sixty-two healthy client-owned geriatric cats, 14 of which developed azotemia during the 12-month follow-up period.


METHODS
Healthy nonazotemic cats were recruited prospectively into the study and followed for 12 months. At the study end-point, cats were categorized into 3 groups according to plasma creatinine concentration. PTH, FGF-23, and additional biochemical variables were evaluated at baseline and after 12 months. GFR was measured by a corrected slope-intercept iohexol clearance method.


RESULTS
FGF-23 concentrations at baseline were found to be significantly increased in cats that developed azotemia (P = .001) compared with cats that did not develop azotemia. A significant positive relationship was identified between FGF-23 and PTH, whereas the relationship between FGF-23 and GFR was negative.


CONCLUSIONS
FGF-23 concentrations predicted development of azotemia in geriatric cats. Positive relationships between FGF-23 and PTH suggest an association between FGF-23 and renal secondary hyperparathyroidism.
Royal Veterinary College, London, UK. natalie.finch@bristol.ac.uk
N C
NC
Finch
R F
RF
Geddes
H M
HM
Syme
J
J
Elliott
D000818:Animals; D053099:Azotemia / Q000097:blood / Q000503:physiopathology / Q000662:veterinary*; D002371:Cat Diseases / Q000378:metabolism*; D002415:Cats; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D005919:Glomerular Filtration Rate / Q000662:veterinary; D008137:Longitudinal Studies; D010281:Parathyroid Hormone / Q000097:blood*; D011446:Prospective Studies; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000503:physiopathology; D018709:Statistics, Nonparametric
D010281:Parathyroid Hormone; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; D003404:Creatinine