All of the following are true about Hypercalcemia, except:
**Core Concept**
Hypercalcemia is a condition characterized by elevated serum calcium levels, which can be caused by various factors including vitamin D intoxication, parathyroid hormone (PTH) overproduction, and malignancies. The normal range for serum calcium is approximately 8.6-10.2 mg/dL.
**Why the Correct Answer is Right**
Hypercalcemia can lead to symptoms such as nausea, vomiting, constipation, and confusion. The pathophysiology involves the increased absorption of calcium from the gastrointestinal tract and the mobilization of calcium from bone. The renin-angiotensin-aldosterone system (RAAS) is activated in hypercalcemia, leading to increased calcium reabsorption in the kidneys. Additionally, the increased PTH levels can stimulate the production of 1,25-dihydroxyvitamin D, further increasing calcium absorption.
**Why Each Wrong Option is Incorrect**
**Option A:** This statement is incorrect as hypercalcemia can indeed cause kidney stones, which are formed from excess calcium in the urine.
**Option B:** This statement is incorrect as hypercalcemia can lead to an increased risk of cardiac arrhythmias due to the effects of high calcium levels on the heart.
**Option C:** This statement is incorrect as hypercalcemia can cause a decrease in parathyroid hormone (PTH) levels in the long term, not an increase.
**Clinical Pearl / High-Yield Fact**
It's essential to note that the presence of hypercalcemia should prompt an evaluation for underlying malignancies, particularly multiple myeloma and lung cancer, which are common causes of hypercalcemia.
**Correct Answer:** D