What is Shar-Pei recurrent fever syndrome?
Shar-Pei recurrent fever syndrome is a hereditary condition that affects nearly one in four Shar-Pei dogs. Affected dogs experience recurrent episodes of fever and inflammation, with no identifiable underlying cause. This causes the dog to feel ill and uncomfortable.
In addition to the visible fever and discomfort that accompanies a fever episode internal damage is often occurring in these dogs. Inflammatory cytokines (chemical signals) released during fever episodes contribute to the production of a protein called amyloid. This amyloid is then deposited in a variety of internal organs, resulting in a condition known as amyloidosis. Amyloid can be deposited in many different internal organs, but it is most problematic when deposited in the kidneys. Recurrent fever episodes can lead to more and more amyloid deposition, which can lead to kidney failure over time. This can shorten the dog’s lifespan.
This condition has been referred to by a number of names, including Shar-Pei autoinflammatory disease, familial Shar-Pei fever, Shar-Pei fever, and familial amyloidosis.
What are the clinical signs of Shar-Pei recurrent fever syndrome?
The most prominent sign of Shar-Pei recurrent fever syndrome is, as its name suggests, recurrent episodes of fever. The first of these episodes often occurs before 18 months of age, but the condition can develop at any age. Affected dogs often have a fever ranging from 103°F (39.4°C) to 107°F (41.7°C), which resolves spontaneously (without treatment) after 12 to 36 hours. Additional signs that may accompany the fever episodes include swelling of the hocks (ankle joint), swelling of the muzzle, abdominal pain, vomiting, and diarrhea.
"Over time, dogs with Shar-Pei recurrent fever syndrome may begin to show
signs of chronic kidney disease (CKD)."
Over time, dogs with Shar-Pei recurrent fever syndrome may begin to show signs of chronic kidney disease (CKD). Signs of CKD may include weight loss, anorexia, vomiting, increased or decreased water intake, lethargy, and pale gums.
How will my veterinarian diagnose Shar-Pei recurrent fever syndrome?
If your Shar-Pei presents to the veterinarian for an unexplained fever, your veterinarian will begin with a thorough physical exam. Not every fever in a Shar-Pei is a case of Shar-Pei recurrent fever syndrome. Your veterinarian will look for other causes of fever, such as a respiratory infection or an infected wound.
If no obvious cause for the fever is found on physical examination, your veterinarian may recommend blood tests. A complete blood cell count (CBC), which examines the red blood cells, white blood cells, and platelets in the blood, may show an elevated white blood cell count and/or anemia. A serum biochemistry profile, which assesses internal organ function, may show elevated liver or kidney values if these organs are affected with amyloidosis. Your veterinarian may also perform tests to rule out tick-borne diseases and other common causes of fevers, depending on your geographic location and your dog’s specific risk factors. A urinalysis may also be performed, because protein in the urine can suggest amyloidosis of the kidneys.
Your veterinarian may also recommend imaging. Radiographs (X-rays) of your dog’s abdomen may show enlargement of the liver, due to amyloid deposits. An ultrasound of the abdomen may show changes within the kidneys and liver that may suggest the presence of amyloid deposits in the liver or kidneys. Biopsy of the liver or kidney can confirm the diagnosis, but this invasive test is rarely performed. Dogs are usually diagnosed and treated based on clinical signs and the results of non-invasive testing.
In 2011, a genetic test was developed that can aid in the diagnosis of Shar-Pei recurrent fever syndrome. While this test is not definitive, genetic testing can identify the likelihood that a particular dog will develop signs of Shar-Pei recurrent fever syndrome over the course of its lifetime. Suggestive clinical signs combined with a suggestive genetic test are also considered adequate to make a diagnosis.
How is Shar-Pei recurrent fever syndrome treated?
During an episode of fever, treatment is focused on supportive care. A fever over 106°F is a medical emergency, requiring immediate treatment, but even lower fevers should be treated medically. Non-steroidal anti-inflammatory drugs (such as carprofen) are often prescribed to reduce fever and alleviate discomfort. If your dog is very ill, your veterinarian may recommend hospitalization for injectable medications and intravenous fluids. Fluids can help bring down your dog’s temperature, while also preventing dehydration. Injections can be used to give medications to a dog that is experiencing nausea, caused by fever and dehydration.
"During an episode of fever, treatment is focused on supportive care."
Once your dog has recovered from the acute episode of fever, the goal shifts to long-term prevention and management. Each episode of fever increases the amount of amyloid deposited within the kidneys, increasing the chance of chronic kidney disease later in your dog’s life. Therefore, the goals of treatment are to reduce the frequency of fever episodes and to reduce amyloid deposition.
Colchicine is the drug of choice for the long-term treatment of dogs with Shar-Pei recurrent fever syndrome. This medication is primarily intended to reduce the deposition of amyloid in the liver and kidneys during fever episodes, but some veterinarians have also noted that it appears to reduce the frequency of these episodes. Colchicine is well-tolerated by most dogs, although gastrointestinal upset may occur.
In dogs that do not respond well to colchicine or do not tolerate its side effects, corticosteroids (such as prednisone) may be used to decrease the frequency of fever episodes. Corticosteroids have a variety of systemic side effects, but the risks of repeated episodes of fever are often greater than the risks that accompany corticosteroid usage.
If your dog is already showing signs of chronic kidney disease due to Shar-Pei recurrent fever syndrome, your veterinarian will also develop a treatment plan to address the kidney disease. Treatments may include prescription diets, fluid therapy, and other medications as needed to control the effects of kidney disease.
What is the prognosis for Shar-Pei recurrent fever syndrome?
Shar-Pei recurrent fever syndrome is not a condition that can be cured. Affected dogs can often be managed, but the condition will affect them for the remainder of their lives. Therefore, this condition is considered to have a guarded (or uncertain) prognosis. While some affected dogs will go on to live relatively normal lives, others will have their lifespan shortened by chronic kidney disease.