Hyperthyroidism and the kidney.
Hyperthyroidism and chronic renal failure (CRF) are both common diseases of older cats. Hyperthyroidism increases GFR by a variety of physiologic effects. Chronic renal failure can suppress total T4 concentrations in cats with concurrent hyperthyroidism, and free T4 is not a useful distinguishing test. Medical therapy (ie, methimazole) is recommended in cats with pre-existing CRF. Overt renal failure occurs in approximately 30% of cats treated for hyperthyroidism. It usually occurs within one month of treatment and tends to remain mild and stable over time. There is no practical way to predict which cats will develop CRF after treatment of hyperthyroidism, although GFR measurement does seem useful.
Langston
Cathy E
CE
Nephrology, Urology, Hemodialysis, and Transplantation Unit, Animal Medical Center, New York, NY, USA. cathy.langston@amcny.org
Reine
Nyssa J
NJ
D000818:Animals; D001806:Blood Urea Nitrogen; D002371:Cat Diseases / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D002415:Cats; D003404:Creatinine / Q000097:blood; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006980:Hyperthyroidism / Q000150:complications / Q000503:physiopathology / Q000662:veterinary*; D007676:Kidney Failure, Chronic / Q000150:complications / Q000503:physiopathology / Q000662:veterinary*; D011507:Proteinuria / Q000150:complications / Q000662:veterinary; D012008:Recurrence; D012079:Renal Circulation; D017595:Renal Plasma Flow; D013974:Thyroxine / Q000097:blood / Q000502:physiology*; D016896:Treatment Outcome
D003404:Creatinine; D013974:Thyroxine