What are the symptoms of Familial Nephropathy (FN)

The symptoms of FN are the symptoms associated with renal failure (regardless of cause) i.e. any type of renal disease.

In the beginning, kidney failure may be asymptomatic (not producing any symptoms). As kidney function decreases, the symptoms are related to the body's inability to regulate water and electrolyte balances, to clear waste products from the body, and to promote red blood cell production.

Dogs with kidney (renal) failure will tend to exhibit the following symptoms:

• excessive water consumption - drinking considerably more than 2 pints of water per day (polydipsia)
• excessive urine volume i.e. weeing frequently - unable to hold a full bladder (polyuria)
• urine that has no colour (clear urine as opposed to the normal pale "yellow" colour)
• reduced growth rate or significant weight loss
• frequent reduced appetite, and unexplained vomiting
• Lethargy and weakness
• Uremic breath odour
• Pale mucous membranes

N.B. Water consumptions varies, depending on the ambient temperature and his activity level. However, as a general rule, a 12kg dog (in a temperate climate) should drink about 56ml of water per kg of weight. This translates to approx. 1.1 pints of water per 24 hours for a 12kg dog. Water consumption in excess of this amount should be investigated further to rule out any health issues.

Progressive Symptoms

If renal failure is not noticed and treatment started, as the disease progresses the symptoms will progress and the following will occur:

• The acid balance within the body will rise and this will alter enzyme and oxygen metabolism. This will cause organ failure.
• Potassium levels will rise due to the body's inability to excrete potassium - this can lead to heart rhythm disturbances.
• Levels of urea (a waste product of protein metabolism) will rise - this leads to low calcium levels (hypocalcemia) and can affect muscle function (the heart) and lead to generalised weakness.
• Anaemia will develop leading to generalised weakness as the red blood cells decrease, a decrease in red blood cells reduces the bodies oxygen carrying ability.
• As waste products accumulate in the blood, loss of appetite, lethargy, and fatigue become apparent. This will progress to the point where mental function will decrease and coma may occur.
• The rising acid load in the body leads to breathing problems with breathing becoming more rapid as the lungs try to buffer the acidity by blowing off carbon dioxide. Blood pressure may rise because of the excess fluid, and this fluid can be deposited in the lungs, causing congestive heart failure.

Unfortunately, juvenile renal failure in dogs is fatal, any treatment regimes can at best prolong the lifespan of the dog but not indefinitely. Most affected dogs do not live beyond their 2nd Birthday. It is very important to recognise renal disease in a dog early, as although treatment cannot prevent the inevitable, quality of life can be preserved longer with treatment than without.

General Observations

One way to identify a pup that might have renal disease is through observation.

Breeders and owners can regularly check the colour of the urine passed by a pup. The first morning release (assuming water hasn’t been available during the night) is probably best. There should be good yellow/orange colour (well concentrated). A youngster that lacks the ability to pass concentrated urine repeatedly should be taken to a vet for a complete urinalysis (‘pee’ analysis).

A test called a "specific gravity" should be performed as well as an analysis for protein (proteinuria). Usually, protein can be checked by using a colour-coded plastic strip. This strip is merely dipped into a urine specimen and the plastic strip changes colour and is checked against a chart on the side of the bottle the strips come in. This strip will test for several things other than protein. A pup with a low specific gravity and excess protein (++) in the urine should be blood tested

Serum chemistry tests (blood tests) will only show significant elevations in specific areas once 75% of both kidneys are destroyed. Elevations in BUN (blood urea nitrogen), creatinine, and inorganic phosphorus suggest kidney disease. These findings coupled with a low urine specific gravity and proteinuria signal end-stage renal disease.

When the serum chemistry tests show "abnormally high levels of urea (BUN), creatinine, and other non-protein nitrogenous substances, a laboratory term called Azotemia is used to identify these specific abnormal levels.”

Generally, once the BUN reaches approximately 120 mg/dl, the dog only has a few weeks before critical illness sets in.

When dogs become critically ill, they will not normally eat, if they do eat, they usually vomit. They may go for two or three days without food, loosing more weight. They will drink a tremendous amount of water and piddle more than usual. The dog will become very weak, and may tremble as if it’s cold as they loose the ability to regulate their body temperature. Since the kidneys are no longer able to filter the body’s waste products, and regulate many important functions essential for life, the animal is essentially poisoning itself with its own waste products and the sad decision to put the dog to rest needs to be made to prevent further suffering.

Those that have lost a dog to renal failure will tell you the loss is more profound with this disease process than any other they’ve experienced. It’s something no one wants to experience as it horrid to watch your beloved dog deteriorate before your eyes. Given the kidneys are so good at functioning; it is not until they are damaged beyond repair that obvious symptoms will be evident; therefore this disease can creep up on an owner with dogs often appearing healthy one minute and at deaths door within a short space of time.