Erythrasma

Key Points
Common skin condition which affects skin folds
Caused by bacterial infection
Consists of patches of skin which are brown or pink in color and accompanied by dryness

Erythrasma is a common skin condition that typically affects the skin folds, including the armpit, groin, and toes. The condition consists of patches of skin which become brown or pink in color and slowly increase in size. This pigment change is accompanied by dryness.

Erythrasma is caused by an infection of the bacteria corynebacterium minutissimum, which may in some cases coexist with other organisms such as yeasts or fungus. The condition may develop in any age, ethnic or gender group, though its appearance is more common in warm climates or in persons who also have diabetes.

Differential Diagnosis (Other conditions with similar appearance)

Acanthosis Nigricans
Seborrheic Dermatitis
Candidiasis
Tinea Infection
Contact Dermatitis
Intertrigo
Psoriasis

Diagnosis
Key Points
Diagnosis based on UV light testing
Microscopy and lesion cultures may be performed to confirm diagnosis

Erythrasma is typically diagnosed based on longwave UV light tests, which cause the affected area to glow pink. Microscopy and/or lesion cultures may be performed to confirm the diagnosis and rule out similar appearing conditions.

Treatment
Typically treated with topical medications
Severe cases may require systemic treatments
Proper skin care may be useful in preventing further infection
OTC Options: Antibacterial soap

Erythrasma is typically treated with topical medications such as antiseptics or antibiotics, specifically Fusidic acid or Clindamycin preparations. Severe cases may be treated with systemic medications, typically the antibiotics Erythromycin or Tetracycline. Proper skin care and use of antibacterial soap may be used to prevent further infection.