Haemodialysis is done when the person is suffering from:

Options

A. Diabetes insipidus
B. Diabetes mellitus
C. Uraemia
D. Goitre

Answer

### Step-by-Step Solution:

1. **Understanding Hemodialysis**: Hemodialysis is a medical procedure used to remove waste products and excess fluid from the blood when the kidneys are not functioning properly.

2. **Identifying Conditions**: The question presents four conditions: diabetes insipidus, diabetes mellitus, uremia, and gout. We need to determine which of these conditions requires hemodialysis.

3. **Analyzing Uremia**: Uremia is a condition characterized by the accumulation of urea and other nitrogenous waste products in the blood due to kidney failure. When the kidneys are unable to filter these wastes effectively, hemodialysis is often required to remove them from the bloodstream.

4. **Excluding Other Conditions**:
- **Diabetes Insipidus**: This condition is related to a deficiency of the antidiuretic hormone (ADH) and does not involve kidney failure or the accumulation of urea.
- **Diabetes Mellitus**: This condition is due to insulin deficiency and primarily affects glucose metabolism, not the elimination of nitrogenous wastes.
- **Gout**: Gout is a form of arthritis caused by the accumulation of uric acid crystals in the joints, but it does not directly relate to kidney failure or the need for hemodialysis.

5. **Conclusion**: Based on the analysis, hemodialysis is specifically indicated in cases of uremia, where kidney function is severely impaired, leading to the accumulation of waste products in the blood.

### Final Answer:
Hemodialysis is done when the person is suffering from **uremia**.

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