Tabitha diagnosed with kidney disease

Tabitha, a slim and active farm cat, is 18 years old and recently diagnosed with low grade kidney disease. She shows no outward sign of kidney problems - her weight has been the same for at least 10 years and she drinks no more than usual.
The kidney disease was revealed at her last senior check when she allowed her vet to take the usual blood and urine samples.
Treating kidney disease in the early stages is easy - a special diet, which preserves kidney function, and plenty of fluids in her food and water bowls.
She has taken to the special diet with gusto. Because it was introduced before the kidney disease affected her appetite she should live another 3 or 4 happy and healthy years.
Tabby visits her vet at least every 3 months to monitor her kidney disease, and to check her blood pressure and body weight.