Vitamin D deficiency rickets is a condition affecting bone development in children, primarily due to inadequate levels of vitamin D, which impacts calcium and phosphate balance.
Analyzing Vitamin D Rickets Features
We need to identify the statement that does NOT represent a characteristic feature of vitamin D deficiency rickets.
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Option 1: Decrease in parathyroid hormone level
Vitamin D deficiency leads to reduced calcium absorption from the gut. This causes low serum calcium levels. Low calcium stimulates the parathyroid glands to increase the secretion of parathyroid hormone (PTH) in a compensatory mechanism (secondary hyperparathyroidism). Therefore, PTH levels actually increase, not decrease. This statement is incorrect. -
Option 2: Decrease in gut calcium absorption
Vitamin D is crucial for the active transport of calcium across the intestinal lining. With vitamin D deficiency, this absorption process is significantly impaired, leading to decreased calcium absorption. This statement is a correct feature. -
Option 3: Decrease in renal phosphate excretion
Secondary hyperparathyroidism (increased PTH) caused by vitamin D deficiency promotes increased phosphate excretion by the kidneys. This leads to low serum phosphate levels, a common finding in rickets. Therefore, a decrease in renal phosphate excretion is generally not considered a feature; rather, an increase is expected. However, compared to Option 1, the hormonal response is more direct. -
Option 4: Increase in serum alkaline phosphatase
In rickets, bone mineralization is defective, resulting in an accumulation of unmineralized osteoid. This stimulates osteoblast activity, leading to elevated levels of serum alkaline phosphatase (ALP), an enzyme produced by osteoblasts. This statement is a correct feature.
Conclusion on Rickets Features
Based on the analysis, a decrease in parathyroid hormone level is contrary to the physiological response seen in vitamin D deficiency rickets, where PTH levels increase to compensate for low calcium.
The feature that is NOT characteristic of vitamin D deficiency rickets is a decrease in parathyroid hormone level.
Important Questions from Vitamin D Deficiency
Consider the following statements with regard to Vitamin D deficiency :
1. Vitamin D deficiency is common in northern latitudes.
2. Vitamin D deficiency is more likely to develop in people with dark skin.
3. Exposure to UV light is advisable in patients with Vitamin D deficiency.
Which of the statements given above are correct?
Which of the following abnormalities occur from vitamin D deficiency in children?
1. Craniotabes
2. Bossing of frontal and parietal bones
3. Muscle hypotonia
4. Shrinking of epiphysis at the lower end of radius
Select the correct answer using the code given below.
- Which one of the following is not characteristic of Vitamin-D resistant rickets ?
- What is the naturally occurring form of vitamin D in the human skin ?
