A urine sediment stains with Prussian blue. The patient probably ...

[olgavictoria]

A urine sediment stains with Prussian blue. The patient probably has:
 
  a. Hemoglobinemia
  b. A membrane defect
  c. Compensated hemolysis
  d. Extravascular hemolysis

Question 2

Which of the following are typical findings in extravascular hemolysis?
 
  a. Increased serum and urine conjugated bilirubin
  b. Increased serum and urine unconjugated bilirubin
  c. Increased serum unconjugated bilirubin and increased urine urobilinogen
  d. Decreased urine and stool conjugated bilirubin

[sultana.d]

Answer to Question 1

ANS: A
When the amount of free hemoglobin exceeds the capacity of plasma salvage systems (e.g., haptoglobin, hemopexin), free hemoglobin can be found in plasma. This hemoglobin is filtered through the kidney; some of the iron will be released and taken up by renal tubular cells that are eventually sloughed off into the urine. The iron can be detected in these renal tubular epithelial cells by giving a positive Prussian blue stain.

Answer to Question 2

ANS: C
During the process of extravascular hemolysis, macrophages phagocytize and break down hemoglobin into its various component parts. Unconjugated bilirubin is thus increased. This is taken to the liver, where it is conjugated. Bacteria in the gut oxidize conjugated bilirubin into various water-soluble compounds that together are called urobilinogen. Some of this is reabsorbed into the plasma and because of its water solubility will be filtered by the renal glomerulus and excreted into urine. This results in an increase in urobilinogen in the urine.

[olgavictoria]

Excellent

[chereeb]

Thanks for the timely response, appreciate it