What is "eczema vaccinatum"

n. a now rare complication of vaccinia superimposed on atopic dermatitis with high fever and generalized vesicles and papulovesicles [syn: Kaposi's varicelliform eruption]

Eczema vaccinatum is a rare severe adverse reaction to smallpox vaccination.

It is characterized by serious local or disseminated, umbilicated, vesicular, crusting skin rashes in the face, neck, chest, abdomen, upper limbs and hands, caused by widespread infection of the skin in people with previous diagnosed skin conditions such as eczema or atopic dermatitis, even if the conditions are not active at the time. Other signs and symptoms include fever and facial and supraglottic edema. The condition may be fatal if severe and left untreated. Survivors are likely to have some scarring (pockmarks).

Smallpox vaccine should not be given to patients with a history of eczema. Because of the danger of transmission of vaccinia, it also should not be given to people in close contact with anyone who has active eczema and who has not been vaccinated. People with other skin diseases (such as atopic dermatitis, burns, impetigo, or herpes zoster) also have an increased risk of contracting eczema vaccinatum and should not be vaccinated against smallpox.

Eczema is also associated with increased complications related to other vesiculating viruses such as chickenpox; this is called eczema herpeticum.