Evaluation of pustular rash

A pustule is a vesicle or bulla containing purulent material. It varies in size and may occur at different levels within the epidermis: subcorneal, intraepidermal, or basement membrane zones. A pustular rash is composed of multiple pustular lesions. The pustules may or may not be sterile and are normally filled with neutrophils.

When the pus is contained within the dermis, the lesion is called an abscess or furuncle. If it is deep and dissects through tissue planes it is called a carbuncle.

This topic covers purely pustular rashes and vesicular eruptions that develop into pustular rashes.