What Is the Pathophysiologic Process Responsible for the Autoimmune Disorder

Multiple Choice

What is the pathophysiologic process responsible for the autoimmune disorder of hemolytic-uremic syndrome (HUS) ?

A) Immunoglobulin A (IgA) coats erythrocytes that are destroyed by the spleen, and remnants are excreted through the kidneys.
B) Verotoxin from Escherichia coli is absorbed from the intestines and damages erythrocytes and endothelial cells.
C) Endotoxins from E. coli block the erythropoietin produced by the kidneys, which reduces the number of erythrocytes produced by the bone marrow.
D) Failure of the nephron to filter urea increases the blood urea nitrogen, which binds to erythrocytes that are subsequently destroyed by the spleen.