Generalized Pustular Psoriasis - A Rare but Severe Skin Condition

Introduction:

Generalized pustular psoriasis is a rare condition where pus-filled blisters are formed, which break, leaving the area tender, inflamed, and red. It requires immediate medical attention. Fever, dehydration, chills, and increased pulse is seen along with it. Although it is a rare condition, it is life-threatening and must be treated as an emergency. Recent studies have suggested that it is independent of psoriasis and has a different inflammatory response. It starts as a red and tender area, progressing quickly into a pus-filled blister. It is also called acute psoriasis of von Zumbusch.

What Is Pustular Psoriasis?

Pustular psoriasis is a variant of psoriasis where pus-filled blisters form on hands and feet. It is painful and cracks easily. When it is widespread, it can be life-threatening. They can form on the skin, beneath a nail, or inside the mouth. Pus-filled bumps (called blemishes) coalesce and burst open, leaving the skin raw and tender when the pus dries. In this red area, new pustules form, which again joins and burst open.

What Is Generalized Pustular Psoriasis?

Generalized pustular psoriasis may be considered to be distinct from psoriasis, according to recent research. It is an inflammatory skin condition with a different immune activation pattern from psoriasis. Due to the recessive IL36RN gene mutations, abnormalities in the cytokine interleukin-36-receptor antagonist signaling take place.

What Are the Risk Factors of Generalized Pustular Psoriasis?

About 10 percent of patients with generalized pustular psoriasis display a history of psoriasis.

Other trigger factors include:

• Drugs such as Aspirin, lithium, iodide, Indomethacin, and some beta blockers.

• Sudden stoppage of corticosteroids.

• Infection.

• Pregnancy.

Withdrawal of strong topical corticosteroids and strong topical preparations such as dithranol and coal tar can cause pustule formation. This is often associated with pre-existing psoriasis and its plaques.

What Are the Clinical Features of Generalized Pustular Psoriasis?

• Generalized pustular psoriasis is an acute condition and has recurrent flare-ups.

• The skin first becomes dry, red, and tender.

• Pustules develop within two to three hours.

• Pustules coalesce after about 24 hours.

• These dry out and peel, leaving a glazed, tender, smooth surface where new pustules form.

• Subsequently, new pustules may appear and erupt every few weeks or days.

• Remission occurs after days or sometimes weeks; the skin will either revert to the previous state or may develop redness. Relapses occur commonly with generalized pustular psoriasis.

Systemic symptoms associated with generalized pustular psoriasis include:

• Fever.

• Chills.

• Headache.

• Increased or rapid pulse rate.

• Loss of appetite.

• Nausea.

• Dehydration.

• Thirst.

• Muscle weakness.

• Leg swelling.

How to Diagnose Generalized Pustular Psoriasis?

Generalized pustular psoriasis can be diagnosed clinically by examining the signs and symptoms. Additional tests can be done for confirmation. These tests can also give an idea of potential complications.

Skin Biopsy: Histopathologically, it shows pustules below the corneal layer along with neutrophilic infiltration.

Laboratory Tests: These can be done to test for bacterial infection in cases of secondary infection.

• Blood Count: To check for anemia, neutrophilia, and lymphopenia.

• Liver Function Tests: To review the functioning of the liver.

• Kidney Function Tests: To check if kidney function is still maintained.

• Serum Levels: Blood levels of calcium, phosphate, and electrolytes can also be done.

What Are the Potential Complications?

Being an acute disorder, in some cases, the disease can be fatal. Therefore it must be given emergency medical care. The Older the patients, the higher the risks.

Potential complications include:

• The pustules can be the site of secondary bacterial infection. In the initial stage, the pustules are sterile.

• Renal (kidney) and liver impairment.

• Protein-losing enteropathy (loss of serum proteins into the intestine).

• Peripheral neuropathy (damage to the nerves outside the brain and spinal cord caused mainly due to diabetes).

• Cardiac failure (occurs when the heart muscle does not pump blood efficiently to meet the body’s needs).

• Electrolyte imbalance due to the loss of water.

• Disturbed protein balance, low albumin, zinc, and calcium.

• The complications can lead to neutrophilia, anemia, and lymphopenia. C-reactive protein can also be seen in these patients.

How to Treat Generalized Pustular Psoriasis?

Since generalized pustular psoriasis is an emergency, immediate hospitalization is required to prevent fluid loss, restore electrolyte balance and stabilize body temperature.

General treatment includes:

• Topically, steroid creams and emollients can be used. Steroid creams must be of low potency.

• Systemically, Acitretin, systemic corticosteroids, Cyclosporin, Colchicine, and Methotrexate, can be used cautiously and according to the need.

• Antibiotics can be given if a secondary bacterial infection is suspected.

Treatment for GPP in adults:

• Oral retinoid.

• Infliximab can reduce inflammation and, thereby, reduce the bumps quickly. Most experts recommend this as the results are fast.

• Methotrexate, Cyclosporine, and Apremilast are other medications prescribed for patients who can not take the above medications.

• Doctors may prescribe two medications as a combination treatment plan to receive better results. Such as Etanercept and Cyclosporine; Infliximab and Methotrexate or Infliximab and Etanercept. The use of combination therapy requires extensive knowledge.

Treatment of GPP in Children:

If generalized pustular psoriasis has an early onset, that is, before the age of 18 years, treatment is as follows:

• Cyclosporine: It is the drug of choice. Improvement is seen within two to four weeks.

• Etanercept: It can be used to treat severe psoriasis plaques in children between the ages of 4 to 17 years. It comes under a group of drugs called biologic. It can be administered two times a week for two months until an improvement is noted.

• Methotrexate: It can be administered in low doses to a child as young as two. It takes a minimum of two weeks for improvement, sometimes longer.

• Other psoriasis medications, such as biologic or phototherapy, can also be used.

What Is the Prognosis of Generalized Pustular Psoriasis?

The prognosis of generalized pustular psoriasis varies. In acute cases, it can be fatal if treatment is not given. For subacute annular and circinate generalized pustular psoriasis, the prognosis is good. The prognosis is poor for those lesions developing from acrodermatitis continua of Hallopeau. It is found to have the worst prognosis. Generally, the prognosis is better if a clear trigger can be identified. A typical example of this is generalized pustular psoriasis during pregnancy.

Conclusion:

Generalized pustular psoriasis is a rare inflammatory disorder characterized by pus-filled blisters that break, leaving red and tender areas. This area may again have pustules (pus-filled blisters). It is an emergency condition requiring immediate medical care. Fever, chills, and headaches may be seen along with it. It is believed to be caused by a gene mutation; however, pregnancy, the sudden withdrawal of corticosteroids, and previous history of psoriasis can act as triggers. Cyclosporine, corticosteroids, and biological medications can be used to treat this condition.