Introduction

Chronic renal failure (CRF) can be tricky to diagnose, because many of the signs of this disease are the same as those caused by other diseases or disorders. However, given time and a willing owner, veterinarians have the skills and the tools to arrive at a definitive diagnosis.

How Chronic Renal Failure is Diagnosed

Dogs with CRF that is severe enough to cause symptoms usually arrive at the veterinary clinic weak, lethargic, depressed, underweight and disheveled, with a history of vomiting, stumbling, diarrhea or constipation, bad breath and dehydration despite abnormally high water intake and urine output. In addition to a thorough physical examination, the initial diagnostic database usually includes a complete blood count, a serum biochemistry profile and a urinalysis. The results of these tests may reveal anemia, elevated blood urea nitrogen, elevated blood creatinine levels, abnormal urine specific gravity and/or urinary tract infection. Direct or indirect blood pressure testing may reveal hypertension, and abdominal ultrasounds and radiographs may identify abnormal kidney tissue or structure, cysts, tumors, obstructions or other disorders.

If the initial diagnostics suggest CRF, more advanced tests can be conducted to either confirm or rule out that disease. These include a urine protein-to-creatinine ratio, urine culture and sensitivity, urine sediment examination, measurement of the glomerular filtration rate and/or a fine needle aspirate or biopsy of kidney tissue. Your veterinarian can describe these procedures to you in greater detail if they become pertinent to your dog.

Special Notes

Urinary tract infections (UTIs) are common in dogs with kidney disease. Resolution of the UTI may help improve kidney function in certain cases of chronic renal failure.