Pathognomic lesion of scabies is?
**Core Concept**
Scabies is a chronic, highly contagious skin infestation caused by the mite Sarcoptes scabiei. The pathognomonic lesion of scabies is a specific skin manifestation that is characteristic and diagnostic of the disease.
**Why the Correct Answer is Right**
The pathognomonic lesion of scabies is the burrow, which is a linear, wavy, or curved track in the skin caused by the mite's movement. The burrow is typically found in the finger webs, wrists, and genital areas. The mite burrows into the upper layer of the skin, causing intense itching and inflammation. The burrow is often accompanied by a small papule or vesicle, and may be accompanied by secondary bacterial infection.
**Why Each Wrong Option is Incorrect**
**Option A:** The vesicle is not the pathognomonic lesion of scabies, although it may be a common finding. The vesicle can be caused by secondary bacterial infection or allergic reaction.
**Option B:** Pruritus is a symptom of scabies, not a pathognomonic lesion. Itching is intense and may be severe, but it is not a specific skin manifestation that is diagnostic of the disease.
**Option C:** The papule is a common finding in scabies, but it is not the pathognomonic lesion. The papule may be a result of the mite's movement or secondary inflammation.
**Clinical Pearl / High-Yield Fact**
The burrow is often easiest to see in the morning after a warm bath, when the skin is most moist. This is because the burrow is more visible when the skin is moist, making it easier to diagnose scabies.
**Correct Answer: C.