Which primary lesion is a raised, fluid-filled sac located under the epidermis that can contain clear, white, yellow fluid or blood?

Which primary lesion is a raised, fluid-filled sac located under the epidermis that can contain clear, white, yellow fluid or blood?

• A. Vesicle
• B. Papule
• C. Pustule
• D. Cyst

Answer: (A)

A vesicle is a small, raised fluid-filled bump that lies within or just beneath the epidermis. Its contents are typically clear, but it can appear white or yellow, and it may contain blood if there is bleeding into the lesion. Because vesicles are usually under 1 centimeter in size, this helps distinguish them from larger blisters. This description—raised and fluid-filled under the epidermis, with possible clear, white, yellow fluid or blood—fits a vesicle best. In contrast, a pustule is pus-filled, a papule is solid without fluid, and a cyst is a closed sac that can contain fluid or semi-solid material and is often deeper.

A vesicle is a small, raised fluid-filled bump that lies within or just beneath the epidermis. Its contents are typically clear, but it can appear white or yellow, and it may contain blood if there is bleeding into the lesion. Because vesicles are usually under 1 centimeter in size, this helps distinguish them from larger blisters. This description—raised and fluid-filled under the epidermis, with possible clear, white, yellow fluid or blood—fits a vesicle best. In contrast, a pustule is pus-filled, a papule is solid without fluid, and a cyst is a closed sac that can contain fluid or semi-solid material and is often deeper.