Question

Which layer of the epidermis is underdeveloped in Very Low Birth Weight (VLBW) infants in the initial 7 days?

• A. Stratum Germinativum
• B. Stratum Granulosum
• C. Stratum Lucidum
• D. Stratum Corneum

Hint:

The barrier stratum corneum matures late in fetal life, so it is thin in VLBW infants right after birth.

Answer 1

The Correct Option is D

Step 1: Recall the layers of the epidermis.
From deep to superficial, the epidermis has the stratum germinativum (basal layer), stratum spinosum, stratum granulosum, stratum lucidum (only in thick skin), and the outermost stratum corneum.

Step 2: Understand skin maturity in a VLBW infant.
A very low birth weight infant is often born well before term, so the skin has not finished maturing. The layer that matures last, closest to birth, is the outer barrier layer.

Step 3: Identify the barrier layer.
The stratum corneum is the tough, keratin-rich outer layer that normally forms a water-tight barrier and takes shape mainly in the last weeks of pregnancy. In a preterm VLBW infant this layer is thin and poorly formed in the first week of life.

Step 4: Explain why this matters clinically.
Because the stratum corneum is underdeveloped, VLBW infants lose water rapidly through the skin (high transepidermal water loss), absorb topical substances more easily, and face a higher risk of skin infection and heat loss in the first week.

Step 5: Rule out the other layers.
The stratum germinativum is the actively dividing basal layer and is present from early fetal life. The stratum granulosum and stratum lucidum are inner layers that are also present, just thinner, but it is the outer corneum whose immaturity causes the well known clinical problems of preterm skin.

Final Answer:
\[ \boxed{\text{Stratum Corneum}} \]