Stones or insoluble mass of crystallised salts formed with in the kidneys is called

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe stones or insoluble masses of crystallized salts that form within the kidneys.

2. **Identifying Key Terms**: The key terms in the question are "stones," "insoluble mass," "crystallized salts," and "kidneys." These terms indicate that we are discussing a specific medical condition related to the kidneys.

3. **Defining the Condition**: The stones or masses formed in the kidneys are known as "renal calculi." The term "renal" refers to the kidneys, and "calculi" refers to stones.

4. **Common Name**: These renal calculi are commonly referred to as "kidney stones." This is a widely recognized term that helps in understanding the condition.

5. **Composition of the Stones**: Kidney stones are primarily composed of crystallized salts, with the most common type being calcium stones, which are often made up of calcium oxalate. Other types may include stones formed from uric acid.

6. **Symptoms and Treatment**: Kidney stones can cause symptoms such as sharp abdominal pain and burning sensation during urination. While small stones may pass naturally, larger stones may require medical intervention or surgery.

7. **Final Answer**: Therefore, the answer to the question is that stones or insoluble masses of crystallized salts formed within the kidneys are called "renal calculi" or "kidney stones."

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