Acute generalized exanthematous pustulosis with lymphangitis triggered by a spider bite

Area of Science:

• Dermatology
• Toxicology
• Pathology

Background:

• Acute generalized exanthematous pustulosis (AGEP) is a rare, severe cutaneous adverse drug reaction, typically linked to medication use (>90% of cases).
• AGEP presents with widespread erythema and non-follicular pustules, usually appearing 1-14 days post-drug administration.
• This condition affects all genders and age groups.

Observation:

• A 39-year-old woman presented with generalized erythema, burning, and rash following a spider bite on her forearm.
• Dermatologic examination revealed a necrotic plaque with linear erythema on the forearm, diffuse erythema, and pustules on erythematous skin.
• The patient also exhibited signs of lymphangitis.

Findings:

• Clinical and histopathologic findings confirmed a diagnosis of AGEP.
• Given the absence of recent drug use, the AGEP was attributed to the spider bite.
• This represents the fifth reported case of AGEP associated with a spider bite.

Implications:

• This case expands the known etiological spectrum of AGEP beyond medication triggers.
• It underscores the importance of considering environmental factors, such as venomous bites, in the differential diagnosis of severe cutaneous reactions.
• Further research may elucidate the mechanisms by which certain spider venoms can induce AGEP-like reactions.