Blood Products and Transfusion Reactions MCQs

This patient has a normal Hb but low MCV. So if you calculate the Mentzer index = MCV/RBC count, it comes to 9.3, which is less than 13 which is indicative of Thalassemia trait. Reference: Robbins & cotran pathologic basis of diseases, 10 th edition Chapter 14, pg 644

Direct Coombs test (DAT) : This test checks for antibodies attached directly to the surface of your red blood cells. The DAT POSITIVE IN : Abo in compatibility Screening for blood compatibility before transfusions. Hemolytic disease of newborn Testing for transfusion reactions. Prenatal blood testing. Drug induced autoimmune hemolytic anaemia Pre-transfusion blood typing. Reference :Robin's basic pathology, 10 th edition, pg: 492

Platelet apheresis Effects of Anticoagulant : Excess anticoagulant goes into patient body during plateletpheresis to prevent clotting The anticoagulant can affect the donor's calcium levels causing hypocalcemia which is rather common after apheresis One common side effect is a tingling sensation in the lips , which can be counteracted by administering calcium-containing antacid tablets. Reference: AABB manual of blood banking, pg 1140

Characteristic histological findings are increased epidermal cell proliferation results in marked epidermal thickening (acanthosis), with regular downward elongation of the rete ridges sometimes described as appearing like test tubes in a Mitotic figures are easily identified well above the basal cell layer, where mitotic activity is confined in normal skin. The stratum granulosum is thinned or absent, and extensive overlying parakeratotic scale is seen. Typical of psoriatic plaques is thinning of the portion of the epidermal cell layer that overlies the tips of dermal papillae (suprapapillary plates) and dilated, tortuous blood vessels within these papillae. Reference: Robbins & Cotran Pathologic Basis of Diseases 10 th edition Chapter 25, pg 1157

Antibody-mediated (type II) hypersensitivity disorders are caused by antibodies directed against target antigens on the surface of cells or other tissue components. The antigens may be normal molecules intrinsic to cell membranes or in the extracellular matrix or they may be adsorbed exogenous antigens (e.g., a drug metabolite). A Coombs test, also known as an antiglobulin test, is of two blood tests used in immunohematology. They are the direct and indirect Coombs tests. The direct Coombs test detects antibodies that are stuck to the surface of the red blood cells. Reference: Robbins and Cotran Pathologic Basis of Diseases, 10 th Edition, Page Number-139.

It is done to prevent transfusion associated graft versus host disease in immunocompromised host Uses: the recommended dose for the irradiation is 2,500 cGy at the center of the irradiation field, with a minimum dose of 1,500 cGy at any point in the field Reference: Robin's basic pathology, 10 th edition, pg:491

Shelf life for various components Red blood cells 35-42 days. Platelets 5-7 days. Fresh frozen plasma 1 year. Cryoprecipitate 1 year. Reference: Wintrobe's Clinical Hematology, 12th Edition, Page Number-677.

The ABO gene , which determines the ABO blood group, resides on chromosome 9 at the band 9q34.2. This gene contains 7 exons Reference: Dacie - pg 486