Pustular is a rare form of psoriasis that appears as clearly defined and raised bumps filled with white, thick pus with red surrounding skin. Though pus is mainly a sign of infection, it does not have much of a role in pustular psoriasis. The condition is not common and affects men and women equally. However boys are affected more often than girls.
Based on your symptoms, pustular psoriasis is classified into various types:
- Sudden and severe acute infection
- Long term or chronic infection
- Generalized or Zumbusch type that affects the entire body with not only skin symptoms but also a generalized feeling of systemic illness associated with fever.
- Ring-shaped, annular or circniate type that is subacute or chronic with only skin symptoms.
- Palmoplantar pustulosis where pustules are localized on palms and soles
- Acrodermatitis continua of Hallopeau where pustules occur on fingertips and nails
- Juvenile or infantile is the least common type of pustular psoriasis that occurs in children.
A combination of genetics and environmental factors induce classical plaque-type psoriasis and pustule psoriasis. Some factors which can also trigger the condition are:
- Taking systemic steroids orally or by injection, and then discontinuing them
- Various drugs like salicylates, iodine, penicillin, lithium antidepressants, hydroxychloroquine, calcipotriol, TNF alfa-blocker biologics and interferon alfa injections
- Strong and irritating topical solutions including tar, steroids under occlusion, anthralin and zinc pyrithione in shampoo
- Sunlight or phototherapy
- Cholestatic jaundice
Though there are so many triggers, it is also never identified in some people.
Signs and symptoms
- Generally, the skin is fiery red and tender and accompanied with symptoms like fever, chills, headache, joint pain, nausea, reduced appetite and general discomfort. There are usually clusters of pustules formed within hours.
- Pustules commonly occur at the anal and genital areas and the bends and skin folds. In rare cases, it may appear on the face too. If it appears on the tongue, it gets difficult to swallow and if it occurs under your nails, your nails can come off.
- The pustules fuse together to form lakes of dry pus within a day that tend to dry and peel off in sheets to produce smooth and reddish skin for new pustules to appear on. An infection lasts for days to weeks and can keep on reappearing for some time. There may also be hair loss within 2-3 months’ time.
- When the pustules improve, most symptoms like headache and fever usually disappears. However in some people it remains bright red with classical symptoms of psoriasis.
- · Ring-shaped pustular psoriasis is more common in young children with less severe symptoms. The ring shaped plaques are recurrent where pustules appear on the ring edges. These symptoms are predominant on the trunk, arms and legs. As the edges expand, the center starts healing while other symptoms are mild or disappear.
- Juvenile pustular psoriasis is mild, usually with only skin symptoms. The condition usually resolves on its own.
- However pustular psoriasis on the palms and soles is usually chronic with red and white pustules on the palms or soles. The condition is usually associated with bone or joint inflammation.
It is important to visit your doctor if you have raised, pus-filled bumps on your skin with symptoms like fever, headache and joint pain. Even having sores on your throat or mouth that makes it difficult to breathe or swallow is a reason to consult your doctor.
Your doctor may perform a complete blood count and elevate the erythrocyte sedimentation rate to help diagnose pustular psoriasis. [note]Your doctor may also do a blood culture or take a urine sample to find out if any organisms grow in the blood or if you have any kidney disorder.[/note]
If required, the pustule’s content may also be cultured and if negative, show there is no infection. Cultures are important as the skin gets damaged during pustular psoriasis, and may lead to an infection.
People suffering from generalized pustular psoriasis are generally admitted to the hospital to ensure they have sufficient fluid intake and bed rest and don’t strain their heart much. Compresses and saline solutions with oatmeal baths provide relief to affected areas. All this is usually sufficient for children suffering from pustular psoriasis.
Topical therapy involves applying medicine to the skin and is the first course of treatment options. [note]They include corticosteroids, coal tar, retinoid, anthralin and vitamin D-3 derivatives. [/note]As there’s no topical drug that is best for everyone and as each drug has its specific adverse effects, it’s better to rotate them.
Sometimes drugs like keratolytics have to be combined with other drugs for more effective treatment. Some drugs like salicylic acid are incompatible with these topical drugs and some drugs like anthralin needs salicylic acid to work effectively.
- Calcipotriene is a form of vitamin d-3 that slows down the production of excessive skin cells to treat moderate psoriasis. It is available as a cream, ointment or solution that is applied to the skin twice a day.
- Coal tar is available as bath oil, cream, gel, lotion, shampoo and other preparations and helps reduce itching while slowing down the production of excess skin cells.
- Corticosteroids like fluocinolone and betamethasone in creams or ointments are applied twice a day or more, depending on the severity of the condition.
- Tree bark extract like anthralin is the most effective antipsoriatic agents available and can cause skin irritation and staining of clothes and skin. Its cream, ointment or paste should be sparingly applied on the skin and rubbed into affected areas on the scalp. However avoid the eyes, forehead and skin that does not have patches and do not apply too much of it.
- Topical retinoid like tazarotene are available as gel or cream and reduces the patch sizes and skin redness. It is usually combined with corticosteroid to reduce skin irritation and to increase its effectiveness. It should be applied on dry as it may trigger irritations when applied to damp skin. Make sure you wash hands after application.
UV-B light is used with topical treatments to treat pustular psoriasis. However its drawback is that it’s time commitment and the accessibility of UV-B equipment.
Systemic agents like retinoid are used to treat the start of pustular psoriasis, which may be followed with PUVA treatment. It circulates throughout the body and includes Acitretin, methotrexate, ethanercept, adalimumab, cyclosporine and alefacept.
[note]In case of milder and chorionic forms of pustular psoriasis, light or topical treatment may be tried first. However if the disease is disabling because of physical, psychological, social or economic reasons, systemic treatment is a better option.[/note]
Conventional therapy like alternative therapy, diet changes, stress-reducing techniques and supplements help reduce the symptoms. However it is always better to consult with your doctor before you start any therapy.
- Avoid all psoriasis environmental triggers like sun exposure, stress and smoking to minimize and prevent flare-ups.
- Alcohol is a psoriasis risk factor in young to middle-aged men and should be avoided or minimized if you have psoriasis.
- There are no diet restrictions for psoriasis; however just eat a well-balanced diet.