Pustular psoriasis is a skin disease. You'll see white bumps filled with pus near or inside red skin blotches. These are called pustules. They can hurt and be scaly, flaky, or itchy.
It's most likely to affect:
- The palms of your hands
- The soles of your feet
- Your fingers and toes
Even though you see pus in your bumps, it's not an infection. You can't catch pustular psoriasis from someone else or give it to others.
Pustular psoriasis usually happens to adults. It's rare for kids to have it. But it can run in families.
You can get pustular psoriasis on its own or with another kind of psoriasis called plaque psoriasis.
Types and Symptoms
There are multiple types of pustular psoriasis. They're based on where the blister outbreaks are or how fast they popped up.
- Palmoplantar pustulosis (PPP): Blisters form on small areas of your body, usually your palms or the soles of your feet. These pus-filled spots can turn brown, peel off, or crust over. Your skin can crack, too. This type of psoriasis may come and go. People who smoke are more likely to get this form.
- Acropustulosis: Small, very painful lesions pop up on your fingertips or toes. The pain can make it hard to use your fingers or toes. In rare cases, it can cause nail or even bone damage.
- Generalized or Von Zumbusch: Red, painful, tender skin blotches show up over a wide area of your body, and pus-filled blisters pop up soon after. Your skin may be very itchy. You also might be very tired or have a fever, chills, dehydration, nausea, weak muscles, headache, joint pain, a fast pulse, or weight loss. This is a rare, serious disease. See your doctor right away if you have these symptoms.
Causes and Triggers
Psoriasis is an autoimmune disease. Your immune system usually sends white blood cells to fight disease in your body. But in this case, they attack your healthy skin by mistake.
A few things can trigger psoriasis flares:
- Medications, such as steroids
- Something that irritates your skin, like a topical cream or harsh skin care product
- Too much sunlight
A mutation, or change, in one of two specific genes (IL36RN or CARD14) may make you more likely to get pustular psoriasis. If you have one of these gene mutations, one of those triggers could set off a flare.
You'll see a dermatologist (a skin doctor) who will ask about your symptoms, your medical history, and any family history of psoriasis.
They may need to take a small sample of your inflamed skin to look at under a microscope. That's called a biopsy.
If you have a severe flare, they may also test your blood for signs of high white blood cell counts; signs that your kidney and liver are working the way they should; and whether you have healthy levels of electrolytes, calcium, and phosphate.
The goal of treatment is to ease your symptoms and control outbreaks. What you take may depend on your type of pustular psoriasis.
Small, local outbreak: Your doctor may try a topical steroid cream first to treat the sores. Coal tar or salicylic acid creams can help with scaly skin. Synthetic vitamin D can help soothe the inflammation. You'll slather on lotions, creams, or ointments to soothe and prevent cracked skin. Then you'll slip on cotton gloves or socks to hold the moisture in. You might get relief from a cool compress on spots that bother you or from an oatmeal bath.
PPP and acropustulosis outbreaks can be stubborn. Your doctor may try ultraviolet light treatments on the inflamed skin. This is called phototherapy.
Oral drugs like cyclosporine or methotrexate may help calm down your immune system. Acitretin (Soriatane) is another drug that can slow skin outbreaks. It's a retinoid, or a synthetic form of vitamin A.
All these drugs can have serious side effects, so you may need to switch treatments from time to time.
If you smoke, try to quit. Smoking makes your psoriasis harder to treat. Try to do things to lower your stress levels, like exercise, yoga, tai chi, or meditation. Some people feel better, although no studies have proven this.
Widespread outbreak: If you have generalized or Von Zumbusch psoriasis, get medical care right away. You'll need fluids along with treatments to prevent infection, ease your fever, and calm inflamed, broken skin. While you're in the hospital, you need to rest, stay hydrated, and keep cool.
Your doctor may treat you with injections of spesolimab-sbzo (Spevigo), a new antibody that blocks signals within the immune system to stop the flare.
Your doctor may also try acitretin, cyclosporine, methotrexate, steroids, or biologics (drugs made from living cells) like etanercept or infliximab to get your flare under control. Once your skin redness and pustule outbreaks have calmed down, you can also try PUVA, where you take a drug called psoralen and then beam ultraviolet light at the affected area of your skin. Apremilast (Otezla) is also sometimes used.
Sometimes, one treatment doesn't do the trick. You may need to combine them to feel better.
What to Do About Scarring
Psoriasis itself doesn’t cause scarring. But patches can be itchy, which may lead you to scratch them. The more you scratch, the more damage you do to your skin.
The best way you can help prevent psoriasis scarring and discoloration is to keep your condition well controlled. Some ways to avoid a psoriasis flare include:
- Manage stress. It’s been shown to worsen psoriasis.
- Use bug repellent and sunscreen to prevent injury to your skin.
- Limit alcohol. It can make psoriasis medications less effective.
- Don’t smoke, and avoid people who do.
- Limit showers and baths to 10 minutes, make them lukewarm, and slather on a fragrance-free moisturizing ointment or cream immediately afterward.
- Try not to cut yourself during shaving.
Taking the right medications can also get your psoriasis under control.