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A 10 mL fetal maternal hemorrhage in an Rh-negative woman who delivered an Rh-positive baby means that the: a. mother's antibody screen will be positive for anti-O b. rosette test will be positive c. mother is not a candidate for Rh immune globulin d. mother should receive 2 doses of Rh immune globulin - b. The rosette screen will be positive if there is a FMH of 10 mL or more. A Kleihauer Betke or flow cytometry should be performed to quantitate the FMH and determine if additional doses of Rh immune globulin are needed to prevent immunization from occurring. A 10-year-old girl was hospitalized because her urine had a distinct red color. The patient had recently recovered from an upper respiratory infection and appeared very pale and lethargic. Tests were performed with the following results: hemoglobin: 5 g/dl. (50 g/L) reticulocyte count: 15% DAT: weak reactivity with poly-specific and anti-C3d: anti-lgG was negative antibody screen: negative Donath-Landsteiner test: positive; P- cells showed no hemolysls The patient probably has: a. paroxysmal cold hemoglobinuria (PCH) b. paroxysmal nocturnal hemoglobinuria (PNH) c. warm autoimmune hemolytic anemia d. hereditary erythroblastic multinuclearity with a positive acidified serum test (HEMPAS) - a . The Donath-Landsteiner test is diagnostic for PCH. The antibody is lgG and is biphasic: hemolysis occurs when the antibody is incubated with cells and cold temperatures and then incubated at 37°C. Often theantibody demonstrates specificity towards the high-incidence antigen P (not to be confused with P1). The antibody screen is usually negative and the patient's red cells are coated with complement. A 10% red cell suspension in saline is used in a compatibility test. Which of the following would most likely occur? a. a false-positive result due to antigen excess b. a false-positive result due to the prozone phenomenon c. a false-negative result due to the prozone phenomenon d. a false-negative result due to antigen excess - d. The strength of agglutination is dependent upon optimal antigen to antibody ratio. Excessive amount of antigen does not allow maximal uptake of antibody per red cell and therefore agglutination is negatively affected leading to weaker or negative results. A 29-year-old male is hemorrhaging severely. He is AB, Rh-negative. 6 units of blood are required STAT. Of the following types available in the blood bank, which would be most preferable for crossmatch? a. AB, Rh-positive b. A, Rh-negative c. A, Rh-positive d. O, Rh-negative - b. When group specific units of Red Blood Cells are not available, group compatible units are selected. Since the patient is AB, group A would be selected to conserve group O units for group O patients. Rh·negative patients should receive Rh•negative units of red blood cells. A 40-year-old man with autoimmune hemolytic anemia due to anti-E has a hemoglobin level of 10.8 g/dL (108 g/L). This patient will most likely be treated with: a. Whole Blood b. Red Blood Cells c. Fresh Frozen Plasma