MI 4.2 & 4.3

Main Concepts

By: Danielle Thompson

University City High School

Main Concepts 4.2

• Lesson 2: Organ Failure
• Concepts:
• 1. End stage renal failure is diagnosed when a patient loses 85 to 90 percent of his/her normal kidney function.
• 2. When the kidneys are not functioning properly, they will not filter adequately and harmful wastes products such as urea, creatinine and blood urea nitrogen build up in the blood stream and the body will make fewer red blood cells because of the lack of the hormone erythropoietin.
• 3. Patients with End Stage Renal Disease have three medical options for treatment, including hemodialysis, peritoneal dialysis and kidney transplant.
• 4. Dialysis is an artificial process that removes waste products and excess water from the blood when the kidneys can no longer function.

​

Main Concepts 4.3

• Lesson 3: Transplant
• Concepts:
• 1. Deciding who receives donated organs is not always a clear-cut issue and involves many difficult decisions guided by federal policies.
• 2. For the best chance of a successful organ transplant, the donor’s and recipient’s tissue types need to match as closely as possible.
• 3. The surgical techniques involved in a live donor kidney transplant require skill, dexterity, and eye-hand coordination.
• 4. The various members of a surgical transplant team work together to make sure the transplant is a success.
• 5. There are many similarities and differences between a heart transplant and a kidney transplant.

​

4.2

• Unregulated diabetes can lead to something called kidney failure, where the kidneys shut down and are unable to work properly.
• This means that blood does not get filtered properly, toxins build up in the blood, and the body becomes poisoned.
• It will lead to death if not treated properly.

�

Diana’s tests

In Lesson 4.2, we met Diana Jones, the sister of Judy Smith. Diana was a long-term diabetic who, in the past, did not manage her diabetes well. Because of this, permanent damage to her kidneys occurred, and we learned that Diana was facing a diagnosis of ESRD, or end-stage renal disease. Her kidneys had failed. This disease is diagnosed using a few different tests, whose results are shown for Diana:

​

Kidneys are responsible for filtering waste from the blood

​

Diseases like diabetes and hypertension increase a person’s risk for renal failure

Symptoms of renal failure include

• Fatigue due to decreased RBC production (erythropoeitin)
• Swelling and high blood pressure due to water retention, electrolyte imbalance
• Muscle cramping due to electrolyte imbalance

​

Signs of Renal failure include

• Increased blood urea nitrogen (BUN) and creatinine
• Low Glomerular Filtration Rate (GFR)
• Blood cells and protein in the urine

Treatment for ESRD

• All these different tests offer clues to the diagnosis of ESRD, which is confirmed with the kidney-based tests: GFR and Urinalysis. If the kidneys fail, what options are available?
• Hemodialysis
• Peritoneal dialysis
• Kidney transplant

Dialysis

Taken from: https://www.youtube.com/watch?v=mi34xCfmLhw

​

4.3

There are federally established agencies and guidelines which dictate who will receive an organ transplant

National Organ Transplant Act (NOTA)

• Organs cannot be bought and sold
• Social status is NOT considered

Organ Procurement and Transplantation Network (OPTN) – follows NOTA and UNOS guidelines to determine who will receive the donor organ

United Network for Organ Sharing (UNOS)

Preference is given to

• Persons waiting for a longer period of time
• Children
• More compatible donor/ recipient match
• Close geographic proximity between donor and recipient

​

Blood Types

• There are four common blood types: A, B, AB, and O.
• Blood is also classified as positive or negative based on Rh factors.
• Blood type and Rh factor simply discuss antigens on the outside of cells.
• Blood cells labeled “A+” contain both A antigens and Rh antigens.
• Someone who is “A-“ contains A antigens, but not Rh factor.

Blood Types

Blood Types

• . A person’s blood is mixed with “Anti-serum” for different blood types.
• Type “A” blood mixed with “Anti-A” serum will agglutinate, meaning that the person has A antigens.
• Type B blood – it will agglutinate with Anti-A and Anti-B serum, meaning both A and B antigens are present.
• It just is a way of finding out what types of antigens are present on blood cells.

Blood Types

Matching Donors to Recipients

1. Blood Typing
2. HLA typing
3. PRA
4. Crossmatch

How do these work?

1. Panel Reactive Antibody screening – tests potential organ recipient’s SERUM against 60 random individuals blood looking for agglutination. High PRA indicates the recipient has many antibodies that could attack a donor organ. Low PRA is favorable for transplant.

​

• Crossmatching – last step before a blood transfusion or organ transplant – a specific donor’s blood is mixed with the recipient’s serum (plasma) to be sure that they are completely compatible.

​

HLA or Tissue Typing

• HLA typing involves testing for the presence of different versions of this gene. There are multiple different versions of this gene broken down into two classes: Class I and Class II. Each class holds several types: HLA-A (there are multiple versions), HLA-B (lots of types) and HLA-Cw (lots of types). Class II holds HLA-DR, HLA-DQ, and HLA-DP – and again, multiple different types.
• For a transplant to be successful, as many of these need to match as possible. The more that match, the more likely that the recipients body will not reject the transplanted organ. For this reason, tissue typing is an essential step performed prior to transplantation.
• HLA typing is performed today using molecular techniques. The DNA is isolated, amplified with PCR, and sequenced to figure out which alleles are present. Again, potential donors and the recipients are tested, with the best match possible being found.

​

For an organ transplant to be successful the donor and recipient must share blood type and have matching Human Leukocyte Antigens (HLA)

​

HLAs are antigens on the surface of your cells that allow your White Blood Cells to recognize “SELF” from “NON-SELF”

​

4.3- Blood types

4.3 Who is the Best Match for Diana?

Louis is most compatible (4 antigens match) and Jack is least compatible (no antigens match)

​

Who gets an organ?

The OPTN Allocates Organs based on the following criteria:

• Compatibility of the donor and recipient.
• Geographical proximity between donor and recipient.
• Time on a waiting list.
• Age of recipient (preference given to children).

​

4.3 Steps of complete live donor laparoscopic nephrectomy �(left side)�Source: Johns Hopkins Dept. of Urology