What is Chronic Kidney Disease?
Kidney disease means there is an abnormality in the structure or function of one or both kidneys. Most often, kidney disease is recognized when kidney function has declined enough to be detected by routine blood and urine tests. The functions of the kidneys are to eliminate waste products, maintain water and electrolyte balance, and produce a variety of hormones. Our goal in managing patients with chronic kidney disease is to recognize the condition while it is still mild and attempt to slow the progression to prevent more serious disease. It is more commonly diagnosed in older dogs and cats, but it is not simply a result of aging.
What are the possible causes of CKD?
The causes of CKD are many and varied including congenital defects such as polycystic kidney disease, chronic infection (pyelonephritis), chronic kidney stones (nephroliths and ureteroliths), immune disease (glomerulonephritis), cancer, and infectious diseases (leptospirosis and Lyme disease). These have all been identified as causes of kidney damage which could lead to CKD, though it is often impossible to determine the original cause for the kidney damage.
What are the symptoms of CKD?
The earliest symptoms are increased thirst (polydipsia) and increased urine volume (polyuria). Other problems include weight loss, poor haircoat and eventually loss of
appetite, vomiting, ulcers in the mouth, “uremic” (foul smelling) breath, hiding, weakness and lethargy. Other important effects of declining kidney function include anemia and high blood pressure. Anemia worsens the weakness, and causes increasing lethargy and loss of appetite, while high blood pressure can cause sudden blindness, stroke- like symptoms, or injury to the kidneys and heart.
What laboratory tests do we start with to diagnose CKD?
Urine tests can help determine whether the kidneys can concentrate urine, if there is infection present, or if there is excess protein loss. The blood tests BUN and creatinine assess kidney function, and are usually done together because they provide different information. They are not very sensitive tests as they do not become abnormal until over 75% of kidney function has been lost. Additional blood tests include measuring electrolytes and pH, as well as screening for infectious diseases. Radiographs, ultrasound, and blood pressure measurement can also aid in the diagnosis and management of CKD.
What are the medical treatments for the disease?
Medical treatments vary as to the stage of kidney disease your pet may have. If your pet has acutely become ill, it may be necessary to be hospitalized for several days until the hydration and appetite have improved. If the CKD was found at the time of a routine checkup, initially treatment may be dietary change alone, but the addition of fluid therapy, antacids, phosphate binders, antihypertensive treatment, and ACE inhibitors are often eventually added and aid greatly in management of this disease.
What are my dietary goals for this disease?
Low protein and low phosphorus are the primary goals in feeding a CKD patient. There are many diets available through your veterinarian to try at home. Commercial diets such as “Urinary” diets for cats that you see in the store are not the same as “Renal” diets. Over the counter diet labels typically list minimum protein content, however it is the maximum protein content that really needs to be regulated and monitored. In general, prescription diets are better at regulating protein and phosphorus content.
What is the typical follow-up treatment to expect with my veterinarian?
Follow-up visits with your veterinarian would be scheduled when your pet was released from the hospital, the timing of which would depend on what stage of CKD your pet has and what complications have occurred. After the patient has been stabilized, recheck visits are at least 3-4 times a year. Recheck visits would likely involve blood and urine testing along with checking blood pressures.