There are no known race differences in incidence. There are no known sex differences in incidence. Lesions begin as pruritic, erythematous macules that progress to papules and pustules. Rash usually clears spontaneously in 2-10 days, rarely recurs, and heals without scarring, but may cause desquamation or leave hyperpigmented macules. Pseudomonas folliculitis is characterized by follicular papules, vesicles, and pustules, which may be crusted.
Lesions involve exposed skin, but usually spare the face, neck, soles, and palms.
Lesions progress to erythematous papulopustules that range in size from 2-10 mm, with a pinpoint central pustule. Rash is not unique in appearance and is most often confused with insect bites. Rarely lesions may progress to chronically draining subcutaneous nodules. Diagnosis is best verified by results of bacterial culture growth from either a fresh pustule or contaminated water sample. Gram stain of a pustule also may be performed.