Author Question: A warm-reactive autoimmune hemolytic anemia found in combination with thrombocytopenia in a patient ... (Read 71 times)

stephzh · **on:** Jun 25, 2018

A warm-reactive autoimmune hemolytic anemia found in combination with thrombocytopenia in a patient is called:

a. Evans syndrome
b. Wiskott-Aldrich syndrome
c. Hereditary spherocytosis with thrombocytopenia
d. Paroxysmal cold hemoglobinuria

Question 2

The Donath-Landsteiner antibody:

a. Binds to the red cell membrane at 37 C
b. Is found in serum and causes lysis of donor RBCs, which have first been incubated at 4 C and then warmed to 37 C
c. Has specificity for Ii blood group antigens
d. Is associated with lymphoma

DylanD1323 · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: A
When thrombocytopenia and a warm-reactive autoimmune hemolytic anemia are found together, the clinical condition is called Evans syndrome.

Answer to Question 2

ANS: B
The Donath-Landsteiner antibody is found in paroxysmal cold hemoglobinuria. It is demonstrated by adding patient serum to donor RBCs that have been chilled to 4 C. The antibody binds at this temperature and activates complement. When the cells are warmed to 37 C, the antibody disassociates from the red cell membrane, after which intense hemolysis occurs because complement has been activated. This antibody is directed against the P blood group antigen. It is not associated with lymphoma but is usually idiopathic. However, it is associated with tertiary or congenital syphilis and is found after some viral infections.