Question

A 45 year old male has multiple grouped vesicular lesions present on the T10 segment dermatome associated with pain. The most likely diagnosis is:

• A. Herpes zoster
• B. Dermatitis herpetiformis
• C. Herpes simplex
• D. Scabies

Hint:

One nerve strip, grouped vesicles, and pain together point to shingles.

Answer 1

The Correct Option is A

The key word in this question is dermatome, the exact strip of skin served by one spinal nerve, and the diagnosis has to explain both the strict single strip pattern and the pain.

1. Herpes zoster: Happens when the chickenpox virus wakes up from where it has been resting in a nerve root and travels down that single nerve. This produces grouped, painful vesicles that stay within one dermatome, matching the T10 pattern exactly.
2. Dermatitis herpetiformis: Produces itchy grouped blisters but on both elbows, knees, and the back, not confined to one nerve strip, and it is not typically painful.
3. Herpes simplex: Produces grouped vesicles too, but in a small local patch around the mouth or genitals, not stretched along a nerve root band across the trunk.
4. Scabies: Produces itchy papules in the finger webs and genital folds from a mite, with no link to a nerve root and no sharp pain.

Only herpes zoster explains a painful, grouped vesicular rash confined to one dermatome, so it is the answer.

Let's summarize:

• A single dermatome distribution with pain is the hallmark of herpes zoster.
• The other three options either spread over multiple body areas or lack the nerve based pain.

So the most likely diagnosis is herpes zoster.