Most harmful anaemia is

Options

A. Microcytic
B. Macrocytic
C. Pernicious
D. both A and B

Answer

### Step-by-Step Solution:

1. **Understanding Anemia**: Anemia is a condition characterized by a deficiency of red blood cells (RBCs) or hemoglobin in the blood, which leads to reduced oxygen transport in the body.

2. **Types of Anemia**:
- **Microcytic Anemia**: This type is characterized by smaller than normal RBCs. It is primarily caused by iron deficiency. Microcytic anemia can often be corrected by addressing the iron deficiency through diet or supplements.
- **Macrocytic Anemia**: This type involves larger than normal RBCs, which are often immature and lack sufficient hemoglobin. The main cause is usually a deficiency in vitamin B12. Like microcytic anemia, macrocytic anemia can also be corrected by replenishing vitamin B12 levels.

3. **Pernicious Anemia**: This is a specific type of macrocytic anemia that is caused by an autoimmune condition leading to a deficiency of intrinsic factor, which is necessary for the absorption of vitamin B12. Even if vitamin B12 is provided, the absence of intrinsic factor means that the body cannot absorb it effectively. This results in a chronic condition that often requires frequent blood transfusions for management.

4. **Conclusion**: Among the types of anemia discussed, pernicious anemia is considered the most harmful due to its autoimmune nature and the inability to correct the deficiency through dietary means alone. It poses a significant health risk and requires ongoing medical intervention.

### Final Answer:
The most harmful anemia is **Pernicious Anemia**.

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