Duff's kidneys are filled with millions of glomeruli, microscopic structures that filter toxins out of his blood. These tiny filters act as gatekeepers in the first step of urine formation, getting rid of the bad stuff and keeping blood proteins circulating as they should. If your dog's glomeruli are inflamed, he has glomerulonephritis.
Duff's glomeruli are contained in the approximately 1 million nephrons housed in his kidneys. When the glomeruli become inflamed, it's often because immune complexes are trapped within the glomeruli. A snowball effect can occur: The damaged glomeruli lose their ability to function and are replaced with scar tissue. As toxins become trapped in the kidneys, the body's immune system takes over, activating its defenses and further compromising the glomeruli. As the glomeruli become compromised, kidney function deteriorates, allowing toxins to accumulate in the body and leading to serious illness.
If your dog has a condition causing regular stimulation to his immune system, his body will form immune complexes that can provoke glomerulonephritis. Duff's immune system may be on alert for many reasons, including heartworm infection, Lyme disease, chronic dental disease, chronically inflamed skin, chronic pancreatitis and other issues. Often, a trigger responsible for stimulating his immune system isn't found, so the glomerulonephritis is idiopathic, or of unknown cause.
The symptoms of glomerulonephritis vary according to how long a dog's been experiencing problems with his glomeruli and according to the underlying cause. Symptoms include weakness, weight loss and blood in the urine. In severe cases of glomerular damage, the dog may be in kidney failure, which results in decreased appetite, increased drinking and urinating, bad breath and vomiting. If the dog has lost a lot of protein from his compromised kidney function, he may accumulate fluid in his abdomen and elsewhere in his body. It's normal to discover the condition only after an annual vet check, when the higher protein levels are discovered in Duff's urinalysis.
When the glomeruli are compromised, large amounts of protein end up in Duff's urine, causing proteinuria, which makes urine tests useful for identifying glomerular disease. As well, the vet will run other tests: One is a complete blood count, which identifies inflammation, infection and anemia; another is a serum chemistry test to measure blood protein concentration. X-rays or ultrasounds may identify any potential abnormalities in the kidneys. A kidney biopsy can confirm glomerulonephritis.
Treating Duff's glomerulonephritis depends on what the root cause is. However, the reality is that the majority of cases of glomerulonephritis are idiopathic, so getting to the heart of the matter is often impossible. If the reason for glomerulonephritis can't be determined, the vet has a number of tools to try to help your dog's kidney function. Immunosuppressive drugs can keep the immune complexes in check so they aren't allowed to become trapped in his glomeruli. Medications to control his blood pressure and minimizing proteinuria are useful, and diet adjustments help to take the load off the kidneys. Duff's prognosis depends on what's causing his kidney problems and how severe his condition is. He'll need to be evaluated at least every three to six months to monitor his blood pressure and check his urine and blood work indicators.
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