The Furry Critter Network

Glomerulonephritis - Issue Description

Back to Canine Health Issues Menu


Issue Name


Other Names
Glomerular Nephritis, GN

Issue Description

Glomerulonephritis is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys.


The presenting complaint in dogs and cats with glomerulonephritis is variable and depends on the severity and duration of urine protein loss as well as the presence or absence of kidney failure and complications.

Clinical signs associated with mild to moderate proteinuria may be non-specific, such as weight loss and lethargy. With severe protein loss, fluid accumulation in the abdomen and in other areas of the body may occur, although this is uncommon. If the glomerular disease is extensive, kidney failure and resultant vomiting, inappetance increased drinking and urination, bad breath, and nausea may occur. Occasionally, signs associated with an underlying infectious, inflammatory, or cancerous disease may be the reason the owner seeks veterinary care.


Persistent, severe elevations in protein in the urine with an otherwise normal urinalysis are the hallmark of glomerular disease.

Other laboratory tests such as a urine protein, creatinine ratio and blood work can be used to help confirm the diagnosis. The only way to definitively diagnosis glomerulonephritis is with a biopsy of the kidney.

Dogs with protein in their urine should be thoroughly evaluated for underlying infectious, inflammatory, or cancerous conditions. Testing may include blood tests for regional infectious diseases, urinalysis, x-rays of the chest, abdominal x-rays or ultrasound.


Glomerulonephritis occurs when large numbers of immune complexes - these are antigen-antibody complexes - circulating in the bloodstream become trapped in the glomeruli as they attempt to pass into the urine. Deposition of immune complexes triggers an inflammatory reaction that damages the glomeruli and results in proteinuria. The antigens bound to the antibodies in the immune complexes arise as a result of some chronic infectious, inflammatory or cancerous disease process. Several diseases have the potential to result in glomerulonephritis.

Some Causes Include:

  • Viral infections
  • Infectious hepatitis in dogs (canine adenovirus 1)
  • Bacterial infections
  • Lyme disease (borreliosis)
  • Ehrlichiosis (an infectious disease transmitted by ticks)
  • Rocky Mountain Spotted Fever (another disease transmitted by ticks)
  • Brucellosis (an infectious disease)
  • Dermatitis (infection of the skin)
  • Gingivitis (infection of the gums)
  • Endocarditis (infection of the heart valves)
  • Prostatitis (infection of the prostate)
  • Pyometra (infection of the uterus)
  • Chronic fungal infections
  • Heartworm disease
  • Leishmaniasis (a protozoal infection rarely encountered in the United States and transmitted by sandflies)
  • Non-infectious inflammatory diseases that have been associated with glomerulonephritis include:

  • Pancreatitis (inflammation of the pancreas)
  • Immune-mediated polyarthritis (inflammation of the joints)
  • Systemic lupus erythematosus (an autoimmune disorder)
  • Neoplasia (cancer)
  • Lymphosarcoma
  • Mast cell tumor
  • Other tumors
  • Despite the long list of infectious, inflammatory and neoplastic disease processes that can result in glomerulonephritis, in as many as 75 to 80 percent of dogs and cats with glomerulonephritis, the underlying cause cannot be identified and the disorder is referred to as "idiopathic."


  • The most important treatment for glomerulonephritis is the identification and treatment of any underlying disease. The dog or cat should be subsequently evaluated for resolving protein in the urine.
  • It is believed that uncontrolled proteinuria leads to progressive kidney damage. Angiotensin-converting enzyme inhibitors (ACEI) are a type of medication often used to help reduce protein levels in the urine. If high blood pressure is present, additional medications may be needed to help lower it.
  • Low doses of aspirin are often given to prevent blood clots and further glomerular damage.
  • Immunosuppressive medications such as prednisone may be used in some cases.
  • Dietary protein restriction may be useful in the management of glomerulonephritis.
  • Potential Complications

  • Increased blood pressure with resultant retinal detachment or hemorrhage may occur. Acute blindness due to retinal detachment may be the first complaint of dogs with glomerulonephritis.
  • Increased coagulability of the blood with resultant blood clots are another complication associated with glomerulonephritis. The lungs are the most common location for a blood clot to lodge, and may result in severe respiratory illness that is difficult to treat.
  • Prognosis

    The prognosis for dogs and cats with immune complex glomerulonephritis is fair to guarded unless the causative underlying disease can be identified and eliminated. A reduction in proteinuria with no increase in blood renal values indicates improvement or response to therapy.

    Back to Canine Health Issues Menu

    Featured Rescues

    "Don't Shop ... Please Adopt"

    laptop pro


    The American Society for the Prevention of Cruelty to Animals® (ASPCA®) was the first humane society to be established in North America and is, today, one of the largest in the world.

    Our organization was founded on the belief that animals are entitled to kind and respectful treatment at the hands of humans and must be protected under the law. Headquartered in New York City, the ASPCA maintains a strong local presence, and with programs that extend our anti-cruelty mission across the country, we are recognized as a national animal welfare organization. We are a privately funded 501(c)(3) not-for-profit corporation, and are proud to boast more than 2 million supporters across the country.

    The ASPCA’s mission, as stated by founder Henry Bergh in 1866, is “to provide effective means for the prevention of cruelty to animals throughout the United States.”

    laptop pro


    If you can’t find the pet you’re looking for on Petfinder, don’t give up. Some shelters maintain waiting lists for specific breeds, so don’t be afraid to ask! There are also breed-specific rescues for just about every breed, and most of them post their pets on Petfinder. (Petfinder can even e-mail you when a pet that fits your criteria is posted — just click “Save this Search” at the top of your search results page.)

    laptop pro

    Rescue Me

    Jeff Gold, Founder, Rescue Me! Animal Rescue Network

    Jeff Gold lives in Watkinsville, Georgia on the same property as Rescue Me's Animal Rehabilitation Center, with 18 rescue animals. Shown with him in the photo to the left are Maggie, Izzie and Cortez. In 2003, after learning there was nobody doing boxer rescue work in Georgia, Gold founded Boxertown, an organization which helped find homes for over 500 boxers during its first two years. Based upon this success, Gold came up with the vision for Rescue Me! ― a network which helps all breeds of dogs, cats and other animals find good homes, anywhere in the world. is also a free service of Rescue Me! and provides the world's largest and most up-to-date directory of animal rescue organizations for all breeds of dogs, cats and other animals, including a comprehensive directory of wildlife rehabilitators in over 150 countries.