The use of Ribavirin to treat chronic hepatitis C in patients receiving azathioprine has been reported to induce severe pancytopenia and may increase the risk of azathioprine-related myelotoxicity. Inosine monophosphate dehydrogenase (IMDH) is required for one of the metabolic pathways of azathioprine.
There are several common underlying causes of kidney disease. 1  In older cats Interstitial Nephritis is most frequently seen. 2  Polycystic Kidney Disease (PKD) is a very common problem in Persian cats - 20-30% of them can be affected. 3  Tumours are occasionally seen in middle-aged and older cats.
Kidney Disease. Kidney disease is a very common finding in the older cat. With early detection, special diet and treatment, many cats can do well. Kidney disease is one of the primary reasons veterinarians recommend screening blood tests in older cats. Hyperthyroidism. Hyperthyroidism is another common disease of older cats.