This is a patient that many of you have seen before. She the star of one of my popular videos, and I’m wondering if any of you can guess what other video she has been seen in? There are clues in the video, so let’s see who can guess correctly first!
I haven’t seen her for awhile and so this is a new issue that she presents to me with. Apparently, she has a cyst on her left chest that she has had for a while but recently, it has become irritated. You can see that over the course of a couple days it got progressively more inflamed and red and painful. She has an inflamed cyst. Many people may call it an abscess, or an “infected” cyst.
I put “infected” in quotes, because technically this is not an infection: When an epidermoid cyst ruptures, it creates a vigorous foreign body inflammatory response – this skin becomes warm, tender, painful, and swells, simulating an abscess. Incision and Drainage (I & D), will confirm the diagnosis of inflamed cyst, when the cheesy material is evacuated, and this often leads to rapid resolution of symptoms.
Here you can see that the internal contents of the cyst have broken down and liquefied, and it’s impossible to define the wall of the cyst. These episodes are often misdiagnosed as “infection” of the cyst, but cultures are usually negative and antibiotic treatments is not required. I did a bacterial culture of this cyst and it proved to be “sterile”, that is, there was no bacterial growth in the culture.
All this being said, we often prescribe antibiotics- it’s hard not to when you see something so red and inflamed and painful.. it seems almost cruel not to! Also, we as dermatologists, will just call the cyst infected, or call it an abscess.
It’s more difficult to explain to patients why we would not call an area that looks angry and red and is painful non-infected. However, I felt I needed to clarify all of this in detail here, for medical education purposes! She felt much better as soon as we drained the cyst, and I will get photos over time as the area improves so you can see what it looks like.