Blood Groups and Blood Types PDF

Blood groups and blood types Physiology/ practical ASHUR UNIVERSITY REPRESENTED BY: Dr. Shatha Mustafa Al Qaseer COLLEGE OF MEDICINE...

Blood groups and blood types Physiology/ practical ASHUR UNIVERSITY REPRESENTED BY: Dr. Shatha Mustafa Al Qaseer COLLEGE OF MEDICINE FIRST GRADE 2023-2024 Blood grouping & Rh. Objectives: 1. review about blood grouping and Rh factor. The ABO blood group system RH factor: Purpose Of Blood Typing. Agglutination: 2. To describe the method of examining the blood groups and Rh. A blood types: A blood type (also called a blood group) is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs). Blood is characterized into different blood groups, based on the presence or absence of these antigens or agglutinogens. The ABO blood group is characterized by two glycolipid antigens, called A and B – depending on whether the RBCs have none, only one or both antigens. blood groups are distinguished as: Type O Type A Type B Type AB.  Purpose Of Blood Typing: 1. In organ transplantation 2. Blood transfusion is a life-saving procedure in all cases of: severe loss of blood life-threatening anemias. However, blood can only be given after blood grouping which is an essential requirement before blood is given to any individual. Agglutination: If someone receives blood of the wrong type, the worst problem is the reaction of the recipient's antibodies on the donor's RBCs. When the body encounters a foreign antigen, agglutination occurs. Agglutination is the clumping of RBCs due to binding of antibodies (part of the immune system) to antigen, and causes blockage of blood vessels and eventually death. In your blood, you have antibodies for the antigens you don't have. RH factor: In addition to antigens of ABO system, the red cells of humans also contain an additional antigen, called Rh antigen (or Rh factor). Rh the D antigen is the most common. Persons whose red cells contain this additional antigen are called “Rh positive” ( Rh +) while those who lack this antigen are called “Rh negative” (Rh –). However, there are no naturally occurring antibodies against Rh (D) antigen. The Rh (D) antigen is not present in body fluids and tissues, but only on red cells. Clinical Significance of Rh factor Although there are no natural anti-Rh antibodies, and they never develop spontaneously, they can be produced only in Rh –ve persons. This can happen in either of 2 ways: In transfusions. When an Rh –ve person receives Rh +ve blood, there is no immediate reaction since there are no antibodies. But during the next few weeks/months, he/she may produce anti-Rh antibodies that will remain in the blood. Later, a second Rh +ve blood is injected, the newly donated red cells will be agglutinated and hemolysed, thus resulting in a serious transfusion reaction. In pregnancy. The most common problem due to Rh incompatibility may arise when an Rh –ve mother (phenotype dd) carries an Rh +ve fetus. Normally, no direct contact occurs between maternal and fetal bloods. However, if a small amount of Rh +ve blood leaks (at the time of delivery) from the fetus through the placenta into the mother’s blood, the mother’s immune system will start to make anti-Rh antibodies. The first-born baby will not be affected. However, during the second and subsequent pregnancies, the mother’s anti-Rh antibodies cross the placental membrane into the fetus where they cause agglutination and hemolysis. The clinical condition that develops in the fetus is called “hemolytic disease of the newborn (HDN). How can hemolytic disease of the newborn be prevented? What is the treatment of severe HDN? The condition can be prevented by desensitizing all Rh –ve mothers by giving them injections of massive doses of anti-Rh antibodies called Rho(D) immune globulin after every abortion, miscarriage, or delivery. BLOOD GROUPING TEST and Rh APPARATUS AND MATERIALS 1.Microscope. 2.Sterile blood lancet, Sterile cotton/ gauze swabs, Alcohol and Toothpicks. 3.Clean, dry microscope slides. 4.Anti-A serum: [contains monoclonal anti-A antibodies (against human). 5.Anti-B serum: [contains monoclonal anti-B antibodies (against human). 6.Anti-D (anti-Rh) serum: [Contains monoclonal anti-Rh (D) antibodies (against human). Determining Blood Type Test: 1.Clean your finger with alcohol and let dry. 2.Prick finger with lancet, near the tip but not too close to the nail. You will need three fairly large drops of blood. Prick so that blood flows freely. Try squeezing up from your wrist if blood does not flow after pricking finger. Three fairly large drops of blood. Figures: Mixing the anti-serum with the blood sample to determine blood type. 3.Use one slide for ABO typing and Rh factor. Place three drops of blood on the slide, add the appropriate typing serum, and determine your blood type. Be sure the serum dropper does not touch the drop of blood. Results should be readable in about a minute. OBSERVATIONS AND RESULTS: It is essential that you should be able to distinguish between “agglutination” and “no agglutination”. The features of each are: 1.If agglutination occurs, it is usually visible to the naked eye. The hemolysed red cells appear as isolated (separate), dark-red masses (clumps) of different sizes and shapes. 2.There is brick-red coloring of the serum by the hemoglobin released from ruptured red cells. What is meant by the terms universal donor and universal recipient? Since type O persons do not have either A or B antigens on their red cells, they are called “universal donors” because their blood can, theoretically, be given to all 4 blood types. Type AB persons are called “universal recipients” because they do not have circulating agglutinins in their plasma and can, therefore, receive blood of any type. THANK YOU