Pustular Psoriasis Facts
Pustular psoriasis. Note the clearly defined, raised bumps on the skin that are filled with pus (pustules). The skin under and around these bumps is red.
A pustular psoriasis is an uncommon form of psoriasis. Pustular psoriasis appears as clearly defined, raised bumps that are filled with a white, thick fluid composed of white blood cells. This purulent exudate is commonly called pus. The skin under and around these bumps is red. Although pus is often a sign of infection, there is no evidence that infection plays any role in pustular psoriasis.
Pustular psoriasis may precede, accompany, or follow the standard form of plaque-type psoriasis.
Pustular psoriasis is classified into one of several types, depending on symptoms. Symptoms may be sudden and severe (acute), long-term (chronic), or somewhere in between (subacute). Widespread pustular psoriasis (von Zumbusch type) affects large areas of the skin and can produce a systemic febrile illness. A ring-shaped (annular, or circinate) type has also been described. It is usually subacute or chronic, and people with this type do not usually have symptoms aside from skin involvement. Pustules may be localized to the palms and soles (palmoplantar pustulosis) or to the fingertips and nails (acrodermatitis continua of Hallopeau). Less common is the juvenile, or infantile type, which occurs in children. Pustular psoriasis in pregnancy (impetigo herpetiformis) is occasionally life-threatening.
Pustular psoriasis is not a common disease. Far more common forms of psoriasis are plaque psoriasis and guttate psoriasis, which account for over 90% of psoriasis. Pustular psoriasis affects all races. In adults, it affects men and women equally. In children, it affects boys somewhat more often than girls. The average age of people with pustular psoriasis is 50 years. Children 2-10 years of age can be affected by the disease, but this is rare.
What Are Causes and Risk Factors of Pustular Psoriasis?
To understand pustular psoriasis, one must recognize aspects of classical plaque-type psoriasis. It is generally agreed that a combination of genetics and environment induces psoriasis, including this pustular subtype. Below is a list of factors that are known to exacerbate pustular psoriasis:
- Acutely stopping high-dose systemic steroids
- Various medications have been associated with exacerbations of psoriasis, including the following:
- Oral iodides (SSKI)
- Phenylbutazone or oxyphenbutazone, nonsteroidal anti-inflammatory drugs (NSAIDs) including aspirin
- Hydroxychloroquine, an antimalarial drug
- Interferon alfa and recombinant interferon-beta injections
- Strong, irritating topical solutions (creams or ointments applied to the skin), including tar, anthralin
In most people, a trigger for the disease is never identified.
What Are Pustular Psoriasis Symptoms and Signs?
Palmoplantar pustular psoriasis, a type of pustular psoriasis that appears on the palms of the hands or the soles of the feet.
In the generalized form, the skin is initially fiery red and tender. Someone may have symptoms such as headache, fever, chills, joint pain, a feeling of general discomfort or uneasiness, decreased appetite, and nausea. Within hours, one may see clusters of pustules.
The most common places these pustules appear are the anal and genital areas and the skin folds in the skin. Pustules may appear on the face, but this is unusual. Pustules can appear on the tongue, which may make it difficult to swallow. They can also occur under the nails and cause the nails to come off.
Within a day, the pustules coalesce to form "lakes" of pus that dry and peel off in sheets. The skin underneath is a smooth reddish surface, on which new pustules can appear. These episodes may recur for days to weeks. They can make someone uncomfortable and exhausted.
Once the pustules improve, most of your other symptoms (such as headache and fever) will usually disappear. Occasionally, the skin may remain bright red, and classical plaque-type disease may follow.
The ring-shaped type is more common in young children. This type tends to be subacute or chronic, and the symptoms are less severe than in the generalized type. Ring-shaped plaques (elevated areas) appear and are often recurrent. Pustules may appear at the edges of the ring. These areas of skin symptoms appear mostly on the trunk but also on the arms and legs. The edges expand, and the center heals. Other symptoms are either absent or mild.
The juvenile, or infantile, type of pustular psoriasis is usually mild without systemic symptoms. The condition often resolves on its own.
Pustular psoriasis of the palms and soles is usually chronic and is often associated with bone or joint inflammation (psoriatic arthritis). The palms or soles are red with white or yellow pustules.
Psoriasis causes the top layer of skin cells to become inflamed and grow too quickly and flake off.
What Specialties of Doctors Treat Pustular Psoriasis?
An individual should visit a physician if he or she has a rash of raised, pus-filled bumps on the skin, especially if he or she has generalized symptoms such as headache, fever, chills, joint pain, a feeling of general discomfort or uneasiness, decreased appetite, and nausea. It is important for a physician to evaluate the individual for a potentially curable health condition caused by an infectious organism as well as consider whether or not one may have another associated chronic problem. A dermatologist is a skin specialist with a particular expertise in evaluating and treating pustular psoriasis.
Visit a doctor anytime one has sores of any type in the mouth or throat that make it difficult to breathe or swallow.
How Do Health Care Professionals Diagnose Pustular Psoriasis?
A doctor may perform blood tests, including the following, in order to make a diagnosis:
- A complete blood count will often reveal reduced lymphocytes (lymphopenia), a type of white blood cell with a large number of another type of leukocyte called polymorphonuclear leukocytes, as high as 40,000 per microliter of blood.
- The erythrocyte sedimentation rate is typically elevated, indicating inflammation.
- Serum chemistry (breakdown of the levels of various components of your blood) can reveal increased plasma globulins (a type protein in the blood) and decreased albumin (a simple protein), calcium, and zinc.
A doctor may take a small sample of a pustule's contents to perform a culture. The results from these cultures and blood cultures are usually negative (no sign of infection). Since the skin is damaged, it may become infected, and the cultures are important. Occasionally, a biopsy of the skin can be examined by a pathologist to help confirm the diagnosis.
What Are Pustular Psoriasis Treatment Options?
People with the generalized form of pustular psoriasis are occasionally admitted to the hospital to make sure they have adequate fluid intake and bed rest and don't lose too much heat or have too much strain on the heart. Bland compresses are applied to the patient's skin, and saline (saltwater) solutions and oatmeal baths help to soothe and heal affected areas. In children with pustular psoriasis, this treatment is often all that's needed.
There are two basic types of treatments for psoriasis: (1) topical therapy (drugs used on the skin) and (2) systemic therapy (drugs taken into the patient's body). All of these treatments may be used alone or in combination.
- Topical therapy: Medications applied directly to the skin are the first course of treatment options. The main topical treatments are corticosteroids, vitamin D-3 derivatives, coal tar, anthralin, or retinoids. There isn't one topical drug that is best for all patients with psoriasis. Because each drug has specific adverse effects, it is common to rotate them. Sometimes drugs are combined with other drugs to make a preparation that is more helpful than an individual topical medication. For example, keratolytic (substances used to break down scales or excess skin cells) are often added to these preparations. Some drugs are incompatible with the active ingredients of these preparations. For example, salicylic acid (a component of aspirin) inactivates calcipotriene (a form of vitamin D-3). On the other hand, drugs such as anthralin (tree bark extract) may require the addition of salicylic acid to work effectively.
- Ultraviolet-B (UV-B) and narrow-band UV-B light: UV-B light is also used to treat psoriasis. UV-B is light with wavelengths of 290-320 nanometers (nm). (The visible light range is 400-700 nm.) UV-B therapy is usually combined with one or more topical treatments. The major drawbacks of this therapy are the time commitment required for treatments and the accessibility of UV-B equipment.
- Systemic agents: For generalized pustular psoriasis, systemic agents such as retinoids may be required from the beginning of treatment. This may be followed by PUVA treatment. For milder and chronic forms of pustular psoriasis, topical treatment or light treatment may be tried first. Patients whose disease is disabling for physical, psychological, social, or economic reasons may also be considered for systemic treatment.
What Medications Treat Pustular Psoriasis?
The goals of medications are to reduce symptoms and prevent complications. In general, topical treatment is of limited use in treating extensive pustular psoriasis. Options to be considered for the limited disease include bland emollients and topical steroids, substances unlikely to produce any local irritation or inflammation. The main topical treatments are corticosteroids, vitamin D-3 derivatives, coal tar, anthralin, or retinoids. Generic drug names are listed below with examples of brands in parentheses.
- Corticosteroids: Clobetasol (Temovate), fluocinolone (Synalar), and betamethasone (Diprolene) are some of the commonly prescribed corticosteroids. These creams or ointments are usually applied twice a day, but the dose depends on the severity of psoriasis.
Systemic medications (those that circulate throughout the body)
- Acitretin (Soriatane) or isotretinoin (Accutane, Amnesteem, Claravis, Sotret) are both vitamin A-like drugs available orally. These drugs are generally used immediately to control the acute pustular eruption and then followed by more long-term medications and therapies as noted below.
- Methotrexate (Rheumatrex): This drug suppresses the immune system and slows the production of skin cells. Methotrexate is taken by mouth (tablet) or as an injection once per week. Women who are planning to become pregnant or who are pregnant should not take this drug. Men must not take this drug if there is a possibility that they will impregnate their partners because it can go into the sperm. The doctor will order blood tests to check one's blood cell count and liver and kidney function on a regular basis while on this medicine.
- Cyclosporine (Sandimmune, Neoral): This orally administered drug suppresses the immune system. A doctor will order blood tests to check kidney and liver function and levels of cyclosporine to monitor for toxicity. Cyclosporine may increase the risk of infection or lymphoma, and it may cause high blood pressure.
- Infliximab (Remicade, Inflectra) is a biologic drug that has been used to treat pustular psoriasis. It must be administered by intravenous infusion.
- Etanercept (Enbrel): This drug is a manmade protein that blocks the TNF, inhibiting inflammation. It is FDA approved for psoriasis and psoriatic arthritis. Etanercept is given as an injection two times per week. The drug can be injected at home. Enbrel affects the immune system and is not used in people with significant heart failure or active infections.
- Adalimumab (Humira) is an antibody that binds to TNF, a key mediator of inflammation. Adalimumab is injected every two weeks and is not used in people with significant heart failure or active infections.
- Ustekinumab (Stelara): This injectable protein drug interferes with the inflammatory cascade by blocking chemical messengers of inflammation to treat pustular psoriasis.
What Are Other Therapies for Pustular Psoriasis?
For the most part, alternative therapies have not been tested with clinical trials, and the FDA has not approved dietary supplements for the treatment of psoriasis. However, the National Psoriasis Foundation does discuss some other therapies on its website. Individuals should check with their doctors before starting any therapy.
Is It Possible to Prevent Pustular Psoriasis?
- Avoiding environmental factors that trigger psoriasis, such as smoking, sun exposure, and stress, may help prevent or minimize flare-ups of psoriasis. Sun exposure may help in many cases of psoriasis and aggravate it in others.
- Alcohol is considered a risk factor for psoriasis in young to middle-aged men. Avoid or minimize alcohol use if one has psoriasis.
- There are no specific dietary restrictions or supplements for psoriasis, other than to consume a well-balanced and adequate diet.
What Is the Prognosis of Pustular Psoriasis?
Complications may include the following:
- Bacterial skin infections, hair loss, and nail loss
- Hypoalbuminemia (abnormally low amounts of albumin in the blood) due to loss of blood protein into tissues
- Hypocalcemia (abnormally low levels of calcium in the blood)
- Kidney damage
- Liver damage
- Malabsorption (in which your gastrointestinal tract doesn't absorb nutrients sufficiently) and malnutrition
The von Zumbusch type (with fever and toxicity) can cause death if it is not treated during the acute phase. In the elderly and those with compromised cardiopulmonary function, pustular psoriasis can be a very serious condition.
Occasionally, acute respiratory distress syndrome can complicate generalized pustular psoriasis. People who have typical psoriasis before they experience a generalized pustular episode tend to do better than people with unusual forms of psoriasis before the pustular flare-up.
Children tend to recover well as long as serious skin infections are avoided.
Types of Psoriasis: Medical Pictures and Treatments
Pustular Psoriasis Support Groups and Counseling
Education is one of the foundations for managing this chronic and typically relapsing condition. People with psoriasis should be familiar with the treatment options in order to make proper informed decisions about therapy. The National Psoriasis Foundation is an excellent organization that provides support to people with psoriasis.
Reviewed on 11/4/2021
Levin, Ethan C., et al. "Biologic Therapy in Erythodermic and Pustular Psoriasis." Journal of Drugs in Dermatology 13.3 March 2014: 342-354.
Posso-De Los Rios, Claudia J., et al. "A Systemic Review of Systemic Medications for Pustular Psoriasis in Pediatrics." Pediatric Dermatology (2014): 1-10.
Robinson, A., et al. "Treatment of pustular psoriasis: from the Medical Board of the National Psoriasis Foundation." J Am Acad Dermatol 67.2 Aug. 2012: 279-288.
Umezawa, Y., et al. "Therapeutic Guidelines for the Treatment of Generalized Pustular Psoriasis (GPP) Based on a Proposed Classification of Disease Severity." Arch Dermatol Res 295 (2003): S43-S54.
Viguier, M., et al. "Efficacy and safety of tumor necrosis factor inhibitors in acute generalized pustular psoriasis." Arch Dermatol 148.12 Dec. 2012: 1423-1425.