Swollen hock syndrome is most common in the Shar Pei breed and goes by many different names, depending on where you are and what the local breeders are referring to the condition as. In some areas it is called Familial Shar Pei Fever, Hock Fever or Systemic Amyloidosis. Not a true fever as such, swollen hock syndrome is caused by an inability of the body, namely the kidneys and liver, to correctly break down and remove amyloidal proteins from the body. These amyloids can collect in the joints, bones and muscles resulting in the swelling and tenderness in the legs, muzzle and other muscles of the body.

This is an inherited, congenital condition that is believed to be caused by an autosomal recessive gene. This means that both the sire and the dam or father and mother must both either have the condition or be carriers of the gene to pass the full condition on to the puppies. Dogs can, however, inherit the gene from one parent that has it and not from the parent that doesn't have the gene. This litter of puppies will all be carriers and while they won't show the signs if crossed with another carrier or a Shar Pei that has had an attack of swollen hock syndrome will have puppies that have the condition. Currently there is no specific DNA test and all that breeders can do is immediately spay and neuter any puppies that show the signs as well as the breeding pair that produced them. Often breeders that are not reputable will continue to breed the carrier, only spaying the obviously afflicted dog of the breeding pair. Potential Shar Pei owners should do some research about swollen hock syndrome in the lines they are considering.

Swollen hock syndrome can range from one or more attacks when the puppy is young and then no further occurrences to frequent and regular attacks throughout the dog's life. As the disease continues to occur there will be greater damage to the kidneys and liver that will not be repaired by the body, resulting in shortened life spans and often sudden death due to kidney and liver failure.

Attacks can be mild in nature to very severe. Mild cases may include swelling of the muzzle and eyes, slight temperature increases and sensitivity of the hind legs to movement or touch. In more severe cases the dog may be in a great deal of pain and may not be able to stand any touch to the muzzle, eyes or back legs, all which will be noticeable swollen. The temperature can rise above 107 degrees which becomes life threatening in itself as the body systems begin to break down at these temperatures. The dog may shiver and cry or whine and seem unable to regulate his or her body temperature. The dog may stand with his or her back arched like a cat and will have severe bouts of diarrhea and vomiting. Typically these dogs will not eat or drink either due to the pain in the muzzle area.

While there is no treatment or prevention for an attack of swollen hock syndrome aspirin and cool water baths and rinses can be used to manage the fever. Pain medications may be administered by the vet if needed. Low protein foods and supplements to support kidney and liver functioning may be an option to discuss with the vet. Notify the breeder immediately if your puppy has an attack of swollen hock syndrome. Most puppies will have an attack between 4 to 18 months if this is going to be a problem with the dog, however sometimes the puppy attacks are misunderstood and misdiagnosed. Rarely adults that have never had an attack as a puppy will start to have them when they are well past the juvenile stage.