Amyloidosis in Dogs
Amyloidosis is a condition in which a waxy translucent substance – consisting primarily of protein – deposits in a dog's organs and tissues, compromising normal functions. This substance is referred to as amyloid. Prolonged excess of this condition may lead to organ failure. The kidney and liver are the most commonly affected, but amyloid deposition can also take place in other organs as well and can have multiple causes. There is some disagreement as to whether amyloid causes the diseased condition or whether it is deposited in the organs as the result of a preexisting diseased condition.
In dogs clinical symptoms are usually related to amyloid deposition in the kidneys. No genetic involvement has been established but familial amyloidosis is known to occur in Chinese shar-peis, beagles, and English foxhound. The breeds predisposed to this disease are: Chinese shar-pei, beagles, collies, English foxhounds, pointers, and walker hounds. Dogs over the age of five and female dogs are at a slightly higher risk compared to males.
Symptoms and Types
As amyloid can deposit in various organs, the symptoms may vary in relation to the organ in which the amyloid has been deposited. Symptoms will also vary by the amount of amyloid deposited, and the reaction of the organ to the amyloid deposition. In dogs, the most common organ in which amyloid deposition is seen is the kidney. However, in Chinese shar-peis, the liver may also be involved. Following are some of the symptoms seen in dogs affected with amyloidosis:
- Poor appetite
- Increased thirst and urination
- Weight loss
- Diarrhea (uncommon)
- Ascites (fluid accumulation in abdomen)
- Edema at various body sites, especially in limbs
- Joint swelling
- Jaundice (in case of liver involvement )
- Chronic infections
- Chronic inflammation
- Parasitic infections
- Immune-mediated diseases
- Systemic lupus erythematosus (SLE)
- Neoplasia (tumor)
- Familial (e.g., in Chinese shar-pei, beagle, and Engligh foxhound)
You will need to give a thorough history of your dog's health, including a background history and onset of symptoms. Your veterinarian will conduct a detailed physical examination, including a blood profile, chemical blood profile, complete blood count, and a urinalysis. These tests may provide information about organ function and give important information about complications that are occurring due to this disease. Urine tests are important if kidneys are being affected by amyloid deposition. Your veterinarian will also take X-ray images and use ultrasound to determine the structural features of the kidneys and where any abnormalities lay. In most cases a diagnosis is confirmed by examining tissue that has been collected during a kidney biopsy.