Laurie Anne Walden, DVM
Chronic kidney disease is common in cats. It can affect cats at any age but is most common in older cats. The disease has no cure. The goals of treatment are to slow the progression of the disease and maintain a good quality of life for the cat.
Functions of the Kidneys
The kidneys filter the blood and excrete waste products into the urine. When the kidneys don’t work properly, these waste products accumulate in the body. The kidneys balance the body’s water level by adjusting the urine concentration. Kidney disease impairs the ability to concentrate the urine and retain water in the body, so animals with kidney disease become dehydrated. The kidneys also help regulate blood pressure, red blood cell production, and acid-base balance.
Signs of Kidney Disease
Kidney disease is already advanced (at least two-thirds of kidney function lost) by the time signs of illness appear. Cats typically have the following signs:
Keep an eye on the size of the urine clumps in your cat’s litter box. Enlarging urine clumps can mean that urine volume is increasing, which is one of the earliest signs of kidney disease. Other disorders (like diabetes) can also increase the urine volume, so larger-than-usual urine clumps warrant a visit to the veterinarian.
As chronic kidney disease progresses, the loss of kidney function leads to further problems:
Causes of Kidney Disease
Acute kidney injury is a rapid loss of kidney function over hours to days. Some of the many possible causes are toxins, infections, and shock. Depending on the cause and severity, acute kidney damage can sometimes be reversed with treatment.
Chronic kidney disease is more common than acute kidney injury in cats. In chronic kidney disease, kidney function gradually decreases over time. The cause is usually not known. The same entities that cause acute kidney injury can lead to chronic kidney failure. Other possible causes are high blood pressure, abnormal kidney development, infection or inflammation of the kidneys, disorders that alter blood flow to the kidneys, and cancer.
Tests are used to diagnose kidney disease, assess the stage of the disease, identify metabolic problems caused by the disease, diagnose other disorders (like thyroid disease) that cats with kidney disease sometimes also have, and possibly reveal the cause of the kidney problem.
Blood tests and urinalysis (analysis of urine) are typically the first diagnostic tests for cats with suspected kidney disease. Blood pressure measurement, urine culture to test for bacterial infection, and ultrasound or x-ray imaging of the urinary tract are also commonly performed for cats with kidney disorders.
Cats with chronic kidney disease benefit from regular testing to monitor disease progression and adjust treatment. In general, these cats should see a veterinarian for blood tests, urinalysis, and blood pressure measurement every 3 to 6 months.
The stage and substage of chronic kidney disease are evaluated with specific tests:
Chronic kidney disease can’t be cured, but it can be managed. The prognosis is variable; some cats can live with the disease for years. If your cat has kidney disease, work with your veterinarian to craft a treatment plan that will give your cat a good quality of life.
Treatment strategies are based on the stage of disease and the individual cat’s needs and may include the following[1,4]:
1. Sparkes AH, Caney S, Chalhoub S, et al. ISFM consensus guidelines on the diagnosis and management of feline chronic kidney disease. J Feline Med Surg. 2016;18(3):219-239.
2. Brown SA. Renal dysfunction in small animals. Merck Veterinary Manual website. https://www.merckvetmanual.com/urinary-system/noninfectious-diseases-of-the-urinary-system-in-small-animals/renal-dysfunction-in-small-animals. Accessed February 26, 2019.
3. International Renal Interest Society. IRIS staging of CKD. http://www.iris-kidney.com/pdf/IRIS_2017_Staging_of_CKD_09May18.pdf. Updated 2017. Accessed February 26, 2019.
4. International Renal Interest Society. Treatment recommendations for CKD in cats. http://www.iris-kidney.com/pdf/IRIS_2017_CAT_Treatment_Recommendations_09May18.pdf. Updated 2017. Accessed February 26, 2019.
Photo by Nicolas Picard on Unsplash
Laurie Anne Walden, DVM
Roundworms are some of the most common internal parasites in dogs and cats. They can also infect humans. According to the Centers for Disease Control and Prevention (CDC), 13.9% of people in the United States have antibodies to roundworms, meaning they have been exposed to the parasite at some point in their lives.
How dogs and cats are infected
Almost all puppies are born with roundworms. The type of roundworm that most often infects dogs, Toxocara canis, transfers from a mother dog to unborn pups through the placenta. T canis can also pass to puppies through the mother’s milk. Infected animals excrete roundworm eggs in their stool, so dogs can be infected by eating feces or swallowing roundworm eggs in the environment. Dogs can also become infected by eating a small animal (like a rodent) that is carrying roundworms.
The most common roundworm in cats is Toxocara cati. Cats and kittens are usually infected by swallowing roundworm eggs in the environment or by eating an infected animal. T cati does not pass to unborn kittens through the mother’s placenta.
Ingested T canis and T cati eggs hatch into larvae in the intestines. The larvae migrate through body tissues to the lungs, are coughed up and swallowed, grow into adult worms in the intestines, and begin producing eggs that pass into the environment through the feces.
Roundworm larvae can remain dormant in body tissues of adult animals instead of maturing in the intestines. These arrested-development larvae can’t be detected by fecal tests for worm eggs because they don’t produce eggs. Dormant larvae in a pregnant dog can become active and move through the placenta to the pups. In other words, a female dog with a negative test for roundworms can pass roundworms to her puppies anyway.
Signs of infection
Infected animals often have no symptoms at all. Dogs and cats (especially puppies and kittens) with lots of roundworms may develop a potbelly, vomiting, diarrhea, weight loss, or dull coat. Heavily infected animals sometimes vomit worms, which look a bit like spaghetti noodles, or pass worms in the stool.
Treatment and prevention in pets
Young puppies and kittens should receive multiple doses of deworming medication. The Companion Animal Parasite Council recommends deworming puppies and kittens every 2 weeks starting at age 2 weeks for pups and 3 weeks for kittens, continuing until they are about 2 months old, and then beginning monthly parasite preventives. Many heartworm preventives also prevent roundworm infection.
To reduce the chance your pets will be infected, remove feces from the environment and try to keep them from eating rodents or other wild animals. Have your veterinarian regularly test your pets for parasites, and give them parasite preventives all year round.
Infection in humans
People can be infected by T canis or T cati if they ingest contaminated dirt or feces. Toxocara eggs can survive in the soil for years. Children and people who own dogs or cats have an increased risk of infection, says the CDC.
Many people with Toxocara infection don’t develop serious disease and have no symptoms. But T canis and T cati larvae can migrate through the bodies of humans, as they do in dogs and cats. Larvae that migrate to internal organs (such as the liver) damage these tissues, a disease process called visceral larval migrans or visceral toxocariasis. Symptoms depend on the organs affected. Sometimes larvae migrate to the eye, causing a disease known as ocular larval migrans or ocular toxocariasis. People with this condition may develop retinal inflammation and vision loss.
Prevention in humans
The CDC recommends these steps to prevent toxocariasis:
For more information
Ascarid (Companion Animal Parasite Council)
Cat Owners: Roundworms and Dog Owners: Roundworms (Pets and Parasites)
Toxocariasis FAQs (CDC)
Photo by Berkay Gumustekin
Laurie Anne Walden, DVM