Regarding hemorrhagic disease of newborn all are true except
## Core Concept
Hemorrhagic disease of the newborn (HDN) is a bleeding disorder that occurs in newborns due to a deficiency of vitamin K-dependent clotting factors. This condition is primarily caused by a lack of vitamin K, which is essential for the gamma-carboxylation and activation of clotting factors II, VII, IX, and X. The newborn's gut is sterile at birth, and it takes some time for the gut flora to produce vitamin K.
## Why the Correct Answer is Right
The correct answer relates to the fact that vitamin K-dependent clotting factors are crucial for coagulation, and their deficiency leads to HDN. Vitamin K administration is a well-established preventive measure for HDN.
## Why Each Wrong Option is Incorrect
To provide accurate information, let's analyze potential incorrect statements regarding HDN:
- **Option A:** If a statement like "Hemorrhagic disease of the newborn is caused by a deficiency of vitamin K" is given as an option, it would be true and not the correct answer.
- **Option B:** If an option states "Vitamin K is given to prevent HDN," this is a true statement and not the correct answer.
- **Option C:** If an option suggests "HDN typically presents within the first 24 hours of life," this might be misleading because classic HDN usually presents between 24 to 72 hours of life, but early HDN can occur within 24 hours if the mother was on certain medications.
- **Option D:** Without specific details on the options, a general incorrect statement could be "Hemorrhagic disease of the newborn is more common in breastfed babies due to lower vitamin K levels in breast milk." While breastfed babies might have lower levels of vitamin K, the statement might be misleading or incomplete regarding the overall risk factors.
## Clinical Pearl / High-Yield Fact
A critical point to remember is that **Vitamin K1 (phylloquinone)** is administered to newborns to prevent HDN. The typical dose is 1 mg given intramuscularly shortly after birth. This is a crucial preventive measure, especially in cases where mothers have been on certain medications that interfere with vitamin K metabolism or in regions with high risk of HDN.
## Correct Answer: D.