Tetany is characterised by which of the following?

Options

A. Lowered blood `Ca^(2+)`
B. Enhanced blood `Na^+`
C. Enhanced blood glucose
D. Enhanced blood `Ca^(2+)`

Answer

To solve the question "Tetany is characterised by which of the following?", we will analyze the options provided and determine which one correctly describes the condition of tetany.

### Step-by-Step Solution:

1. **Understanding Tetany**:
- Tetany is a medical condition characterized by involuntary muscle spasms, cramps, and twitching. It primarily affects the hands, feet, and voice box.

2. **Identifying the Cause**:
- The primary cause of tetany is an electrolyte imbalance, particularly involving calcium levels in the blood.

3. **Analyzing the Options**:
- **Option 1: Lowered blood calcium level**: This is known as hypocalcemia, which is indeed associated with tetany. This option is correct.
- **Option 2: Enhanced blood sodium level**: Sodium levels do not play a significant role in causing tetany. This option is incorrect.
- **Option 3: Enhanced blood glucose level**: Blood glucose levels are not related to tetany. This option is also incorrect.
- **Option 4: Enhanced blood calcium level**: This refers to hypercalcemia, which is not associated with tetany. This option is incorrect.

4. **Conclusion**:
- The only correct answer is **Option 1: Lowered blood calcium level**, as it directly relates to the condition of tetany.

### Final Answer:
Tetany is characterized by **lowered blood calcium level** (hypocalcemia).

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