Acute generalized exanthematous pustulosis

Acute generalized exanthematous pustulosis

Acute generalized exanthematous pustulosis

Acute generalized exanthematous pustulosis (AGEP) is a rare skin condition characterized by the rapid onset of numerous small, sterile pustules on an erythematous base. It is often associated with fever and leukocytosis and is typically triggered by medications.

Presentation

AGEP presents with a sudden eruption of pustules, usually within 1-2 days after exposure to the causative agent. The pustules are non-follicular and appear on a background of edematous erythema. Commonly affected areas include the face, trunk, and intertriginous zones. Patients may also experience fever, malaise, and elevated white blood cell counts.

Causes

The most common cause of AGEP is a hypersensitivity reaction to medications. Antibiotics, particularly beta-lactams and macrolides, are frequently implicated. Other drugs, such as calcium channel blockers and antimalarials, have also been associated with AGEP. In rare cases, infections or environmental factors may trigger the condition.

Pathophysiology

AGEP is believed to be a type IV hypersensitivity reaction, also known as a delayed-type hypersensitivity reaction. This involves the activation of T-cells and the release of cytokines, leading to the recruitment of neutrophils and the formation of pustules. The exact immunological mechanisms are still under investigation.

Diagnosis

Diagnosis of AGEP is primarily clinical, supported by the patient's history of drug exposure and the characteristic appearance of the rash. A skin biopsy can be performed to confirm the diagnosis, showing subcorneal pustules and a dermal infiltrate of neutrophils. Patch testing may help identify the causative drug.

Treatment

The mainstay of treatment for AGEP is the withdrawal of the offending drug. Supportive care, including topical corticosteroids and emollients, can help alleviate symptoms. In severe cases, systemic corticosteroids may be required. The prognosis is generally good, with resolution of symptoms within 1-2 weeks after discontinuation of the causative agent.

Prognosis

AGEP typically resolves without long-term sequelae once the offending drug is discontinued. The pustules usually heal without scarring, although post-inflammatory hyperpigmentation may occur. Recurrence is rare if the triggering agent is avoided.

Related pages

• Drug eruption
• Hypersensitivity
• Pustular psoriasis
• Dermatology

• 

  Acute generalized exanthematous pustulosis