• Common inflammatory condition of skin folds that occurs when apposing skin surfaces rub against each other, such as seen in diaper dermatitis or irritation by antiperspirants, or shaving products.

Common features include the following:

• Induction or aggravation by heat, hyperhidrosis, moisture, maceration, and friction.

• Location in the axillae, inguinal, and intragluteal creases; often occurs under pendulous breasts and abdominal folds and as a complication of obesity.

• Possible colonization by secondary infection such as Candida albicans, particularly in patients with diabetes.

• Lesions typically have a scalloped, “active border”.

• Generally spares the scrotum and penis.

• Positive KOH examination and fungal culture for dermatophytes.

• Lesions are “beefy red” in color.

• Satellite pustules often noted beyond the border of the plaques.

• Positive KOH examination for budding yeast.

• Positive culture for Candida species.

• Eczematous lesions may be seen elsewhere on the body.

• Patients often have an atopic history.

• May be indistinguishable from inverse psoriasis.

• When lesions are present on the glans penis, nonspecific balanitis (more commonly seen in elderly men) and candida balanitis should be considered in the differential diagnosis.

• Pruritus ani also may be confused with inverse psoriasis.

• Secondary overgrowth with Candida species and tinea must also be considered.