1. Kidney failure

2. Why are your kidneys so important?
1. The kidney is important in keeping conditions in the body
constant – what is this called?
2. What substance is removed by the kidney?
3. What is the name of the vessel that carries the blood to the
kidney?
4. What happens to the blood as soon as it enters the kidney?
5. What is not filtered out into the kidney tubules?
6. How much glucose is reabsorbed into the blood?
7. How much water and mineral ions are reabsorbed into the
blood?
8. What is the name of the vessel that carries the blood away from
the kidney?
9. What is the final product called once it has passed through the
kidney and out via the ureter?

3. Problems in the kidney
• Nephritis - sometimes
the kidneys become
inflamed e.g. due to
bacteria
• Kidney stones - hard
mineral deposits formed
in the kidney. They can
pass into the urine and
larger ones may stick in
the ureter.

4. Kidney failure
• When both kidneys stop working, this is kidney
failure.
• It may be caused by kidney disease, injury, high
blood pressure, poisoning or dehydration.
• If a person’s kidneys don’t work, waste products
(urea) build up in the bloodstream and the
person will die without treatment – either dialysis
or a transplant.

5. What is kidney dialysis?
• Kidney failure means
death, unless the function
of the kidneys is
replaced.
• Dialysis replaces kidney
function – filters and
cleans blood.
• Depends on diffusion
along concentration
gradients from blood to
dialysis fluid.
Kidney dialysis in action

6. How does a dialysis machine work?

7. How a dialysis machine works

8. What is a kidney transplant?
• Failed kidneys replaced by
single healthy kidney from
donor.
• Donor usually dead, but may
be living.
• To prevent rejection by the
immune system:
– The kidney is as close a tissue
match as possible.
– The recipient takes
immunosuppressant drugs for
life.

9. Which is best – dialysis or transplant?
Dialysis: Transplant:
• Machines usually • No special diet.
available. • No sessions of dialysis.
• No problems with • Relatively inexpensive,
tissue matching. particularly after surgery.
• Has to happen at least • Need donor, often not available.
twice a • Need tissue match.
week for life. • Have to take
• Expensive immunosuppressant
long-term. drugs for life.
• Have to watch diet. • Surgery every ten years or so.

10. Overcoming lack of organ donors
• Xenotransplantation
• Stem cell research