Papule
A papule is a small raised area of skin, solid rather than fluid-filled, that can be felt as well as seen. It is distinguished from a macule, which is flat, from a pustule, which contains pus, and from a nodule, which is larger and deeper.
Small, raised, and solid. A papule is something you could feel with your eyes closed, and pressing it releases nothing, which is what separates it from the fluid-filled words nearby.
It sits in a family of terms that describe raised areas by size and depth. A nodule is larger and sits deeper, extending further into the skin, and it typically feels firm. A plaque is raised but broad relative to its height, more a plateau than a bump. A vesicle contains clear fluid and a pustule contains pus, both of which a papule does not.
That vocabulary is doing more work than it appears to. Which of these words applies is one of the first things established in an examination, because it narrows the range of processes that could produce what is being looked at, before anybody has committed to naming anything.
The term recurs across conditions with nothing else in common. Acne produces papules, and so does rosacea, which is one reason the two are so frequently confused. What separates them there is not the papules but what accompanies them: acne produces comedones and rosacea does not.
As with every word in this set, it describes what something looks like and says nothing about what it is.
Last updated .