Three Signs Your "Acne" Is Really a Serious Skin Condition

It will probably come as no surprise that acne is one of the more common skin disorders out there. Most of us have either experienced it firsthand or know someone who has. While acne is more prevalent among teens and young adults—impacting around 85% of those between the ages of 12 and 24, according to a Yale Medicine estimate—it affects men and women of all ages, including more than 12% of men in their forties.

Given its ubiquity, along with the fact that acne can present a range of symptoms that vary in both severity and appearance, it makes sense that other skin conditions could easily be mistaken for acne, and vice-versa. The thing with that is, while another skin condition may look or feel like acne, it could be something else entirely—and potentially something more serious that requires different treatment altogether.

“For example, if it comes on suddenly, especially where there is minimal or no history of acne, that could be bacterial folliculitis,” says Gibran Shaikh, MD, board-certified dermatologist and clinical instructor in the Department of Dermatology at Mount Sinai. “Similarly, if it doesn’t respond to typical acne treatments, it could be fungal folliculitis or even rosacea.”

“Or it could be something more serious, like hidradenitis suppurativa,” says Dr. Shaikh. Hidradenitis suppurativa is an autoinflammatory condition that shares some of the same characteristics as acne, but if left untreated—or mistakenly treated as acne—can spiral out into a painful, self-perpetuating cycle of cystic flare-ups and complex scarring.

“I've seen a lot of patients that self-treat, that self-diagnose, and what you end up seeing is things like a contact rash or more severe irritation or worsening of the condition, because it's actually not acne,” says Nicole Lee, MD, MPH, FAAD, board-certified dermatologist and owner of Epoch Dermatology.

The good news is that, while hidradenitis suppurativa is a chronic condition, effective treatments exist, and getting a handle on it early can make all the difference, says Dr. Lee. “Go see a dermatologist as soon as you suspect anything. Don’t wait.”

Here are three signs that your “acne” might actually be hidradenitis suppurativa.

It shows up in specific areas of the body

“The first thing I would point to is the areas of the body that are affected,” says Dr. Shaikh.

One of the similarities between hidradenitis suppurativa and acne is that they both originate at the site of an obstructed or occluded hair follicle. So both conditions are really only going to show up—only can show up—where hair follicles exist. Hidradenitis suppurativa, however, tends to impact an even smaller subset of locales.

“Compared to even an extreme form of cystic acne, I would say what's unique to hidradenitis suppurativa is the locations,” says Dr. Lee. “Acne is typically on exposed areas, like your face, your arms, your chest, and your back, whereas hidradenitis suppurativa typically is at the folds of your skin where you have the most sweating, like the armpits, groin, or butt. I've even seen patients who have it on the back of the neck.”

If your symptoms are manifesting in an area that gets a lot of skin-on-skin friction, that’s your first sign that it could be hidradenitis suppurativa.

It doesn’t produce comedones

When you’re dealing with acne, you often tend to have comedones—blackheads and whiteheads. That’s not always the case, but it’s pretty standard. “To be clear, you can have just purely cystic acne; that's a thing that exists,” says Dr. Shaikh. Hidradenitis suppurativa, in contrast, presents mostly as nodules and cysts under the skin.

“The idea with acne, which also involves the hair follicle, is we think about all of its manifestations as kind of outward. You see a whitehead or a blackhead, or you see a bump or something on the skin. With hidradenitis suppurativa, much of that process is going on within,” says Dr. Shaikh.

“You can have deep, painful cysts in both diseases, but if someone came to me and said, ‘Listen, I only have cysts, and I have never had a single blackhead or a single whitehead, and I've never had a pustule; it's all just like these deeper nodules,’ and they happen to be on an anatomical area that is not classic for acne, I would be raising my eyebrow.”

It leaves behind a “network” of scarring beneath the skin

While acne can cover patches of skin, those areas are essentially comprised of discrete, individual lesions. In other words, you could rub your finger over an affected area and feel where one bump ends and another begins. Hidradenitis suppurativa may start out like this, with cysts spaced out by areas of healthy skin, but over time they can connect, forming a subdermal network of scar tissue, says Dr. Lee. “That usually gets us saying, “OK, we're in a whole different category right now. We need to manage this differently.”

When a cyst bursts, it creates what is called a sinus tract— “a little hole in the skin where you'll see drainage of pus or potentially blood,” explains Dr. Shaikh. While sinus tracts will sometimes route directly to the surface of the skin, in the case of hidradenitis suppurativa they’ll often connect to the site of a previously ruptured cyst, leaving behind a tunnel of scar tissue. Over time, without intervention, that can become a complex network of scar-tissue tracts beneath the skin.

“Acne scarring can certainly happen, and it's something that we see a lot, but sinus tract formation—a collection of all these ruptured cysts and scar tissue underneath the skin—is classic for hidradenitis suppurativa,” says Dr. Shaikh. “I've never seen acne do that.”