Intertrigo – a rash in your creases

Intertrigo is a rash that appears in creases and folds, such as under the arms, in the folds of the neck, behind ears, under a belly, between the buttocks and in the groin. It is common for intertrigo to appear in multiple folds on the same person, and affects males and females of any age.

Overweight people may get these rashes more, as may people who sweat a lot or have a tendency for skin problems.

Intertrigo may appear and disappear, or linger for many weeks or months. The way intertrigo looks on each person will be a bit different, as the cause can be different.

Symptoms of intertrigo

Intertrigo-affected skin is inflamed, red, and uncomfortable. It can start to crack and become moist over time.

Why does intertrigo develop?

Intertrigo is caused by both genetic and environmental factors. Crease skin has a higher temperature than other areas of skin, moisture cannot evaporate as easily, and friction in creases can result in chafing. The microorganisms in creases may multiply in warmer, moist environments and become problematic if they overgrow.

There are two types of intertrigo: infectious and inflammatory. You may have both. Intertrigo may appear just on one side, and if bacterial in nature, unlikely to be symmetrical. When it’s inflammatory, it’s like to affect both sides in more or less the same way.

Microbes responsible for intertrigo

• Candida albicans (yeast) – develops quickly, itchy, moist, peeling red and white skin, with some small papules/pustules
• Corynebacterium minutissimum (erythrasma) – brown patches, low scale, or often no symptoms
• Trichophyton rubrum and T. interdigitale (tinea, tinea cruris (groin), athlete’s foot) – slowly spreads, irregularly-shaped plaques, peeling and scaling
• Staphylococcus aureus and S. pyogenes (impetigo) – quick onset, moist blisters, crusty red base, contagious, could also be boils/nodules that are very painful, or follicle infections

Inflammatory conditions that cause intertrigo

• Flexural psoriasis – defined, red, shiny, scaly patches, hard to get rid of, common in the groin, symmetrical, may crack
• Seborrhoeic dermatitis – undefined salmon-pink patches, ranges in severity, can be asymmetrical, red patches on face/scalp are flaky
• Atopic dermatitis (eczema) – itchy, acute eczema may blister and be red, but chronic eczema may be dried, thickened skin
• Contact irritant dermatitis – irritant-dependent – could be sweat, urine, friction, deodorants, soaps, laundry detergent, washing
• Contact allergic dermatitis – allergen-dependent – could be fragrances, preservatives, medications, underwear, rubber, elastic, nickel
• Hidradenitis suppurativa – chronic, boil-like follicle nodules and papules
• Hailey-Hailey disease – painful, shallow blisters, rare genetic condition, starts age 20-40, worse in summer
• Granular parakeratosis – red-brown scaly rash, itchy, rare
• Fox-Fordyce disease – dome-shaped papules, often asymptomatic but may be itchy, reduced sweating

Treatments for intertrigo

Treating the underlying cause is important, so figuring out what the cause is is paramount. Infections should be treated with the relevant antimicrobial, while inflammatory conditions should be managed.

Often this means with steroid cream, but steroids in creases can cause stretch marks due to skin thinning. Speak to your skin healthcare professional for advice.