Chronic renal failure, a degenerative disease of the kidneys, is common in ageing cats. Unfortunately, this condition cannot be cured, only treated to slow its progress and reduce symptoms. Many cats suffering from chronic renal failure develop digestive problems, including constipation, which can cause serious discomfort and poor litter box habits.
Constipation is not a disease in itself, but often occurs as a symptom of other problems. It's characterised by small, hard, dry stools that pass infrequently. This condition is most common in middle-aged or older cats, but may affect animals of any age. If allowed to become chronic, constipation may caused megacolon, a condition in which the colon cannot contract properly.
Cats with chronic renal failure often have problems with dehydration. Their disease causes them to urinate more, and most are unable to drink enough to replace the lost water. According to Tanya's Feline Chronic Renal Failure Information Center, dehydration may cause very dry stools, making it hard for a cat to have bowel movements. Overly high calcium levels or low levels of potassium may also contribute to constipation.
In addition to the obvious signs of hard stool and infrequent defecation, cats with chronic renal failure and constipation may show other symptoms. Intestinal discomfort may cause them to have less interest in food. They may vomit before, during, or after using their litter boxes, and may defecate outside of the box. In severe cases, cats may suffer from a high heart rate and accelerated breathing. If constipation is allowed to continue, built-up toxins may induce lethargy or cause a cat to faint.
In most cases, the veterinarian can feel hard stool through the cat's abdomen, but constipation is not always this obvious. The cat may need to be X-rayed to diagnose constipation. According to Cat World, blood or urinalysis may also be performed, especially if the cat shows symptoms of kidney problems. These tests can help detect dehydration and poor kidney function.
Cats with constipation from CRF may be treated in a number of ways, depending on the cause of their problem. If dehydration is a problem, the cat may need to be fed a diet with a higher water content, or may require fluid therapy. This may be administered by the vet, or given subcutaneously at home. If a disruption of the calcium/potassium balance is responsible, the vet may recommend dietary supplements to improve nutrition.