**Question:** In Hemolytic anemias the urobilinogen level in the blood would

A. increase
B. decrease
C. remain normal
D. remain normal

**Correct Answer:** A. increase

**Core Concept:**
Hemolytic anemias are a group of disorders characterized by the premature breakdown of red blood cells (RBCs), leading to an increased production of heme-derived waste products. One such waste product is urobilinogen, which is a precursor to bilirubin. Urobilinogen is primarily produced in the liver from the breakdown of heme and then conjugated bilirubin, before being excreted into the gastrointestinal tract and urine.

**Why the Correct Answer is Right:**
In hemolytic anemias, the rapid breakdown of RBCs results in an increased production of urobilinogen. Since more urobilinogen is produced, the level of this waste product in the blood increases, leading to an elevated urobilinogen level. This elevated level can be detected through urine tests, which is a non-invasive method for monitoring the severity of the hemolytic process.

**Why Each Wrong Option is Incorrect:**

B. Decrease: This is incorrect because the primary event in hemolytic anemias is the breakdown of RBCs, not a decrease in their production. Consequently, the level of urobilinogen, a waste product resulting from RBC breakdown, would increase.

C. Remain normal: Similar to option B, this is incorrect because the primary event in hemolytic anemias is the breakdown of RBCs, not a normal production. As a result, the urobilinogen level would increase.

D. Remain normal: This is incorrect for the same reasons as options B and C. Hemolytic anemias result from RBC breakdown, not normal production. Consequently, the urobilinogen level would increase.

**Clinical Pearl:**
A high level of urobilinogen in blood is a valuable indicator of hemolysis or RBC breakdown. This test can be used to monitor the severity of the anemia and guide treatment decisions. In hemolytic anemias, physicians may order a urine bilirubin test to assess the degree of hemolysis and adjust the therapy accordingly. A high level indicates increased RBC breakdown, while a low level may suggest inadequate therapy.