Pannus formation takes place in :-

Options

A. IDDM
B. SCID
C. Rheumatoid arthritis
D. Hashimoto's disease

Answer

**Step-by-Step Solution:**

1. **Understanding Pannus Formation**: Pannus refers to an abnormal layer of fibrovascular tissue or granulation tissue that forms on the surface of a tissue, particularly in joints. It is associated with inflammation and can lead to damage of the underlying structures.

2. **Identifying the Conditions**: The question lists several conditions: IDDM (Insulin-Dependent Diabetes Mellitus), SCID (Severe Combined Immunodeficiency), Rheumatoid Arthritis, and Hashimoto's disease. We need to determine which of these is associated with pannus formation.

3. **Linking Pannus to Joint Diseases**: Pannus formation is primarily linked to inflammatory diseases that affect the joints. Among the options provided, Rheumatoid Arthritis is known to cause significant joint inflammation and damage.

4. **Understanding Rheumatoid Arthritis**: In Rheumatoid Arthritis, the immune system mistakenly attacks the synovium (the lining of the joints), leading to inflammation. This inflammation can cause the synovium to thicken and form the pannus, which can invade and destroy cartilage and bone.

5. **Conclusion**: Based on the understanding of pannus formation and its association with joint diseases, we conclude that pannus formation takes place in Rheumatoid Arthritis.

**Final Answer**: Pannus formation takes place in Rheumatoid Arthritis.

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