Analysis of the Patients ABO RHD Blood Group Results - Essay Example

rасtiсаl Lаbоrаtоry Ехеrсisе Name: Institution: Date: Analysis of the patient’s ABO RhD blood group results The patient’s ABO RhD blood group as interpreted from the DiaMed CAT reaction results is AB Rh-ve. This means that the patient’s blood group is AB and the individual does not have the Rh antigens on the surface of red blood cells. In the first test tube, the anti-A antibodies formed visible clumps with the red blood cells in the patient’s blood. In the second test tube, it was also noted that the anti-B antibodies formed visible clumps with the patient’s red blood cells. This is an indication that the patient contains both type A and type B antigens. Being of type A and type B antigens, the individual’s blood plasma does not have either antibodies to A or antibodies to B. In the third test tube, which contained rhesus antibodies, it was noted that there was no clumping of red blood cells. This was an indication that the patient’s blood cells do not possess rhesus antigens (RhD negative). The figure below shows the CAT reactions in the first three boxes: Figure 1: CAT reactions in test tube 1-3 for the patient’s AABO RhD blood grouping Transfusion of incompatible ABO blood to patients is the most common cause of fatalities related blood transfusion. These reactions occur due to formation of natural antibodies to the antigens of ABO red blood cells that the patient do not possess in their blood system (Reid, et al., 2012). When transfused with incompatible blood, there is an immediate reaction between antigens and antibodies, which may be fatal if not detected in time (Pfisterer, et al., 1968). The implication of the above AOB RhD blood grouping results is that, the patient can safely receive blood from a compatible plasma donor with any blood group without rhesus antigens, i.e. AB RhD-ve, A RhD-ve, B RhD-ve or O RhD-ve. An interpretation of the patient’s antibody screen results In the second test, the patient’s antibody screen was performed in Saline Immediate Spin (IS) Phase to establish the presence of unexpected antibody in the blood serum. Patient serum was added to 3 screen vials and spun to observe agglutination in IgM class of antibodies. The results of the test are shown in the anti-gram table below: Figure 2: Anti-body screening results of patient serum From the antibody screening results shown n figure 2, it can be seen that the patient showed reactivity with some antigens (+). A positive reaction is an indication of the presence of that particular antigen in the patient’s serum, while 0 indicates absence. These are the antigens present in the patient’s blood serum. Patient antigens suspected to be present are: D C E c e Cw Kk Kpb Fya Fyb JKa JKb This results only indicates the presence of cold reactive antibodies. It would be necessary to confirm the presence of these antigens by conducting further tests. Further Investigations 1. Anti-body Identification A positive reaction in the IS phase only indicates the presence of IgM cold reactivity antibodies. It is preferred that further investigation is done to see if the reaction disasters or persists. This is achieved by proceeding to the incubation phase, followed by the anti-globulin phase (AHG phase). In the incubation phase, bovine serum albumin is used to promote agglutination of red blood cells when they come into contact with the IgM class of antibodies (Rudmann, 2005). The optimum temperature of reaction of these antibodies is 37oC. If after spinning the tubes after the incubation phase, hemolysis and/or agglutination is observed, the AHG phase will be performed. The reason for proceeding to the AHG phase is to identify smaller antibodies of the IgM class that due to their small size, they do not cause visible agglutination (Malarkey & McMorrow, 2011). In the AHG phase, AHG serum is added to all the vials after washing with saline to remove the albumin and serum. Examination for agglutination both microscopically and macroscopically is then performed. 2. Phenotyping After obtaining the results for all the phases described in part 1 above, an antigram with the results is prepared. To confirm the identity of the antibodies, the RBCs of the patient blood has to be phenotyped to ensure that they show negative for the antigen that corresponds to the antibody identified (Higgins, 2012). Identification and phenotyping of antibodies is critical because it is here that clinically significant antibodies will be detected in the patient’s blood. For transfusion purposes, it is important to perform antibody identification as part of the compatibility test process. It helps to identify any unexpected antibodies in the serum of the patient’s blood (Kawthalkar, 2012). Serious side effects may occur if an individual with an antibody is exposed to a corresponding antigen from a donor. General Discussion Blood Unit Selection Prior to carrying out blood transfusion to the patient, there are a number of tests that need to be done to ensure that the transfusion will be safe in the blood system of the receiver. In this part, we will discuss the most important investigations to do before selecting a blood unit for transfusion. a. Testing infectious disease agents During the pre-transfusion stage, the donor blood should be tested for infectous disease markers. These disease markers include: Hepatitis B virus (HBV) – The first test for this virus (surface antigen or HBsAg) is done to detect the outer envelope of HB virus, and a second test is performed to detect the virus itself. Hepatitis C virus (HBC) – The tests done will be to detect the virus nucleic acid. Antibodies to the core of the hepatitis B and hepatitis C viruses (Anti-HBC) – This test is performed to detect the presence of an antibody to HB or HC viruses produced during or after infection (Hillyer, 2007). Human immunodeficiency virus (HIV) – There are two tests involved; the first test looks for a protein in the virus envelope and the antibody to the virus (anti-HIV), and the second test to investigate the virus itself by looking its nucleic acid. Syphilis – Tests are carried out to establish specific antibodies to the bacterium Treponema pallidum that may be present in blood even years after the infection is treated. If the test turns positive, the blood cannot be used (White, 2009). Human T-lymphotropic virus (HTLV) – The presence of anti-bodies to HTLV has to be done on the blood sample, and if turns out to be positive, further investigation is done to confirm the result. Other additional tests that may be performed depending on the circumstances of an individual donor include: active malaria test, T-cruzi, West Nile Virus, Cytomegalovirus (CMV), Hepatitis E Virus (HEV) and other Non-specific reactions. The importance of investigating the blood for these infectious diseases is to ensure that a safe blood supply is provided to the patient who needs it (Simon, et al., 2016). This practice prevents the passing of infectious diseases from donor to patient during blood transfusion. b. Confirmatory tests – to screen out false positives and false negatives Sometimes, a test may give false positive or false negative results. For example, a test may indicate that donor blood is infected by a certain disease when it is not actually true, or fail to indicate an infection where there is actually an infection. This can occur in several blood screening tests. Further investigations are therefore, carried out on reactive screening tests to establish if the screening results are actually true. This is important because, one, it verifies the status of the donor so that an appropriate action may be taken. Secondly, it helps to obtain accurate screening results that can assist in making appropriate decisions. In addition, it provides epidemiological data in the donor population. c. ABO compatibility/Crossmatching test Compatibility testing or cross-matching is the last step performed in pre-transfusion. After the recipient and donor blood samples have been ABO and Rh typed, cross-matching should be done to find out the compatibility of all other red blood cell antigens (Klein & Anstee, 2008). This test is done by, first, selecting a unit of blood from a recipient and donor with the same ABO Rh type. Serum obtained from the patient is then mixed with the donor red blood cells and then incubated at 37oC. If clumping is observed after some time, the blood is incompatible, if clumping is not observed, then the blood is compatible (Mujahid & Dickert, 2015). This test is necessary to establish if blood clumping will occur due to unexpected antibodies that may be present either in the donor or patient blood. Further investigations have to be carried out if clumping occurs, an implication of incompatibility. Cross-matching Techniques i. Tube Indirect Anti-globulin Test (IAT) In this technique, RBCs are incubated at 37oC to allow the serum to react with antigens on the RBCs in vitro. The cells are then washed with saline and anti-globulin reagent added to observe if cells are coating with antibodies. When centrifuged, RBCs coated with IgG antibodies do not show agglutination directly. Adding an additional antibody creates a “bridge” between the complement coating the RBCs or the antibodies, causing agglutination. ii. Column Agglutination This system is based on the sieving effect of micro-particles of glass bead. The test is carried out in a micro-column. During blood screening, the RBC agglutinates get trapped in the glass bead micro-particle matrix during the centrifugation stage, while those that are un-agglutinated form a pellet at the column bottom. Special requirements to be considered when dispatching blood for this patient ABO platelets and plasma compatibility It is preferred that the blood issued to a patient from donor be of same platelet and cryoprecipitate identity as that of the patient. This becomes important if the patient has a history of reactions to the past blood transfusions or had many transfusions. However, this is not very critical and is limited to the availability of ABO compatible platelets (Chernecky & Berger, 2007). In case this is not available, there should be a listed order of preference for the patient’s ABO RhD blood grouping. This is determined by the health care team that oversees the patient care. If the plasma is frozen, then it has to be administered as soon as possible, possibly within an hour, to prevent loss of coagulation activity (Simon, et al., 2016). References Read More