Causes of Kidney Failure
Some of the more serious causes of kidney failure include:
Hereditary and Congenital Abnormalities
These types of kidney disease are very frustrating to try to control or repair. Most cats with abnormally constructed kidneys will develop kidney failure and do not live anywhere near a normal life span.
A few hereditary conditions that lead to kidney failure include:
- Polycystic kidney disease (PKD), though uncommon, creates cystic areas in the kidneys where normal function and structure are lost. Eventually, even if the cat reaches maturity, gradual increases in metabolic waste products and signs of kidney disease prevent optimum quality of life and the animal dies or is mercifully euthanized. If found, it typically occurs in Persian/Exotic cats.
- Renal agenesis, also called kidney aplasia, causes the cat to be born without one or both kidneys.
- Renal hypoplasia is a condition where the kidney(s) do not develop completely.
- Renal cortical hypoplasia is a condition where the cortex of the kidney(s) develops incompletely.
- Renal dysplasia is a condition where the kidneys develop abnormally. Renal failure develops with protein loss in urine.
- Renal tubular dysfunction occurs when the filtering tubules of the kidneys do not function properly.
Infections of the urinary tract of cats are, unfortunately, very common. Generally arising from gradual spread of external bacterial organisms near the external urinary orifices, the bacteria multiply and invade the urethra, then into the bladder (causing what is termed cystitis), and occasionally further retrograde up the ureters and eventually into the kidneys.
Another less common means of kidney infection arises from a blood-borne dispersion of bacteria from a remote area such as an abscess or skin infection. Leptospirosis bacteria, for example, can have a severe effect on kidneys.
Another severe bacterial infection (Borrelia burgdorferi) may be caused by the bite of a tick. This infection causes Lyme Disease, which damages the kindey's ability to filter body waste products and transport of those waste products into the urine. Even after eliminating the bacteria with antibiotic therapy there may remain permanent structural damage to vital renal tissues -- and kidney failure ensues.
Systemic fungal infections such as Blastomycosis, Coccidioidomycosis (Valley Fever), and Histoplasmosis can attack nearly any tissue or organ in the body, including the kidneys. Most systemic fungal diseases are geographically oriented.
Trauma to Kidney
Direct trauma to the kidneys can result in kidney failure. Although rare, cats that are run over by vehicles can suffer permanent and irreparable kidney trauma. Also, sudden physical shock to the kidney tissues from being struck by vehicles, baseball bats, kicking, or falls from a height, etc. can result in suffusive bleeding into the kidney tissue and permanently impair renal function.
Blockage of Urine Flow
The most notable condition seen in cats from blockage of urine flow from the kidneys involves kidney stones or bladder stones or urethral obstructions. The obstructions caused by these mineral concretions (usually called struvite uroliths) can increase back pressure on the affected kidney, which permanently damages kidney function and causes what is termed hydronephrosis -- a kidney swollen under pressure with backed up urine.
Cats with bladderstones often obstruct when a stone passes from the bladder but cannot be voided past the os penis -- the bone present in the male feline's penis. There is an inherent lack of room for the urethra to dilate in the area of the os penis and small bladder stones often dam up the urine flow at this site. Surgical intervention is often required in these emergency urinary tract blockage cases.
Tumors, cysts, abscesses and scar tissue, if present in critical areas of the urinary tract, can create obstructive situations where the urine flow from a kidney is compromised. This can result in damage to delicate kidney tissue structures, which is often permanent. If enough tissue is destroyed or its function impaired, kidney failure will occur.
The amount of pressure required to cause osmosis to stop
The term for the hip and related area
A medical condition involving excessive thirst
The bone inside the penis of canine animals
The inside part or region of something
The dilation of the pelvis due to obstruction of urine
An increase in the number of bad white blood cells
The failure of the kidneys to perform their proper functions
The tubular shaft found between the kidneys and the bladder
A tube found between the bladder and the outside of the body; used to assist in urination.
A condition in which waste builds up in the bloodstream
A type of nervous system disease in which the patient is unable to regain control over certain muscles, usually those in the neck and jaw
Found underneath the dermis
Something that is related to the whole body and not just one particular part or organ
A group or clumps of capillaries
Inducing death on an animal or putting them to sleep
The amount of pressure applied by the blood on the arteries.
Any female animal that has given birth.
The smaller veins or arteries that extend out from larger arteries.
When a certain organ or vital tissue fails to properly or fully develop.
Term used to imply that a situation or condition is more severe than usual; also used to refer to a disease having run a short course or come on suddenly.
Any medication that is designed to aid in relieving pain without being a sedative.
A medical condition in which the body has lost fluid or water in excessive amounts
Moving downward or toward the end
A condition in which growth and development are not up to normal standards
To carry something away
A passage in the body with walls
The furthest distance from the middle or the top of a body
A procedure used to get waste out of the blood when the kidneys are unable to function
To make something wider
A localized infection, usually a lesion filled with pus. Can be large or small in size.