A doctor has ordered a test for serum bilirubin. The patient goes to a pathologist who collects his blood. The pathologist should collect this blood in a test tube containing

Options

A. Anti-coagulant sodium citrate
B. Anti-coagulant double oxalate
C. Anti - coagulant fluorides
D. No anti-coagulant

Answer

To solve the question regarding the appropriate test tube for collecting blood for a serum bilirubin test, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Bilirubin**:
- Bilirubin is a yellow pigment formed from the breakdown of red blood cells (RBCs). Specifically, it is produced from the heme portion of hemoglobin when RBCs are broken down in the liver.

2. **Purpose of the Serum Bilirubin Test**:
- The test measures the level of bilirubin in the serum, which can indicate various health issues, including liver disease or hemolysis (breakdown of RBCs).

3. **Role of Anticoagulants**:
- Anticoagulants are substances that prevent blood from clotting. They are often used in blood collection tubes for various tests to ensure that the blood remains in a liquid state.

4. **Requirement for the Bilirubin Test**:
- For the serum bilirubin test, it is crucial that no anticoagulant is present in the test tube. This is because we want the RBCs to break down naturally, releasing bilirubin into the serum for accurate measurement.

5. **Evaluating Options**:
- The options provided include various anticoagulants:
- **Sodium citrate**: Used for tests requiring platelet aggregation.
- **Double oxalate**: Used for glucose and lactate tests.
- **Fluoride**: Used for hematological tests.
- Since all these options contain anticoagulants, they are not suitable for the bilirubin test.

6. **Conclusion**:
- The correct choice is a test tube that contains **no anticoagulant**. This allows for the natural breakdown of RBCs and the accurate measurement of bilirubin levels in the serum.

### Final Answer:
The pathologist should collect the blood in a test tube containing **no anticoagulant**.

---