Rickets caused by excessive renal phosphate loss and apparent abnormal vitamin D metabolism in a cat.
Rickets was diagnosed in a 1-year-old cat with a history of weakness, osteopenia, and recurrent fractures. Processes causing rickets include vitamin D deficiency caused by inadequate, nutrition, lack of exposure to sunlight, defective metabolism of parent vitamin D to active metabolites, inherited vitamin D receptor defects, hypoparathyroidism, chronic renal failure, renal loss of phosphate, or malabsorptive states resulting from gastrointestinal or hepatic diseases. On the basis of analysis of serum 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D2 and D3 concentrations, serum biochemical analysis, and urinary fractional clearance of electrolytes, the causes of rickets in our cat, were most compatible with a combination of excessive loss of phosphorus via the kidneys and deficient or abnormal hepatic 25-hydroxylation of vitamin D. Calcifediol treatment and twice daily administration of phosphate salts resulted in clinical improvement and increases in mineralization of the skeleton, as evidenced on radiographic evaluation.
Department of Medical Sciences, University of Wisconsin, Madison, WI 53706, USA.
R A
RA
Henik
L J
LJ
Forrest
A L
AL
Friedman
D000818:Animals; D002112:Calcifediol / Q000097:blood / Q000378:metabolism / Q000627:therapeutic use*; D002117:Calcitriol / Q000097:blood; D002371:Cat Diseases / Q000188:drug therapy / Q000378:metabolism*; D002415:Cats; D004872:Ergocalciferols / Q000097:blood; D005260:Female; D007668:Kidney / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism* / Q000652:urine; D012016:Reference Values; D012279:Rickets / Q000188:drug therapy / Q000378:metabolism / Q000662:veterinary*; D014807:Vitamin D / Q000378:metabolism*; D014808:Vitamin D Deficiency / Q000378:metabolism
D004872:Ergocalciferols; D010710:Phosphates; D014807:Vitamin D; C003564:1,25-dihydroxyergocalciferol; D002117:Calcitriol; D002112:Calcifediol