What is Inverse Psoriasis?

Inverse psoriasis is also known as flexural or intertriginous psoriasis. That’s because it affects the body parts where two skin areas are touching or rubbing on each other. These are usually skin folds located under the arms, in the groin area, under the breasts (in women), etc.

What is Inverse Psoriasis? | TreatPsoriasis.com
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Overview of Inverse Psoriasis

People prone to inverse psoriasis flare-ups are usually already suffering from another type of this chronic skin condition, such as plaque psoriasis (Psoriasis Vulgaris).

Because it only appears in skin folds, inverse psoriasis can look like a rash. It forms as smaller, smooth, shiny, and reddish patches of skin. 

The affected part of the skin is not scaly, thick, or raised. Instead, the skin is inflamed, moist, itchy, sensitive to touch, and prone to infections. 

It is not uncommon for painful and bleeding cracks (fissures) to appear in the skin. Those can be difficult to treat in such sensitive areas of the skin, especially if they are further irritated by sweat and friction.

The parts of the body usually affected by inverse psoriasis are:

  • Armpits
  • Groin
  • Navel 
  • Behind ears
  • Around genitals
  • Between buttocks
  • Under breasts

Symptoms of Inverse Psoriasis

Lesions that appear in the skin folds are the main symptom of inverse psoriasis. These are usually patches of bright red, smooth, shiny, and sometimes cracked skin. On darker skin, they can appear as purple. The lesions are sensitive and often painful.

Causes and Risk Factors for Inverse Psoriasis

Inverse psoriasis is an autoimmune disease. The overstimulation of the immune system causes it to perceive healthy skin cells as intruders. 

When this happens, your immune system responds by attacking those cells. That response is the cause of inflammation and the abnormally rapid production of skin cells, known as psoriasis.

So, we can say that genetic predisposition is a risk factor. Almost one in two of all people with psoriasis have relatives with the same condition. 

Other risk factors for inverse psoriasis are:

  • Obesity
  • Hyperhidrosis (over-sweating) 
  • Smoking
  • Vitamin D deficiency
  • Medications
  • Infections
  • Alcohol abuse
  • Skin trauma or irritation

Inverse psoriasis often co-exists with other psoriasis types. Up to thirty percent of people with plaque psoriasis also develop inverse psoriasis at some point in their life. 

Obesity can trigger inverse psoriasis. If you are overweight, parts of your body are more likely to rub together. Also, excess skin will create deeper folds prone to inflammation, sweating, and infections.

Hyperhidrosis can also trigger inverse psoriasis or make the existing condition worse.

Inverse Psoriasis Diagnosis

A dermatologist can diagnose inverse psoriasis with little trouble. The examination and visual inspection of the skin in the affected area will usually do the trick.

Sometimes, a small sample of the skin may be necessary to rule out other similar conditions such as:

  • Intertrigo
  • Tinea versicolor
  • Seborrheic dermatitis, and
  • Jock itch (tinea cruris)

Inverse Psoriasis: The Bottom Line

Inverse psoriasis does not usually affect large portions of the skin. To prevent the outbreaks or help the already affected parts of the body heal, you should make some lifestyle adjustments. Try to lose weight, quit smoking, and avoid alcohol. Use powder to absorb excess moisture in the skin folds. Wearing loose clothes made of natural materials can also help reduce the friction between areas of the skin prone to inverse psoriasis flare-ups.