Inverse psoriasis is an immune-mediated inflammatory skin condition that occurs in skin folds, such as in the armpits and under the breasts. It causes itchy, scaly plaques to appear. They may also appear shiny.
The location and appearance of these lesions tend to set inverse psoriasis apart from other types of psoriasis. People may find lesions occur in skin folds of the body, including, but not limited to, the groin, armpits, under the breasts, and the abdomen.
Inverse psoriasis affects 21% to 30% of people with psoriasis. It is also more common in people with deep skin folds.
This article examines the symptoms of inverse psoriasis and its similarities to other conditions. It also looks at treatments, causes, home care tips, prevention, and when to consult a doctor.
Inverse psoriasis may cause discolored lesions in the skin folds to appear smooth and shiny. Typically, people will find that the areas are itchy. They may also experience pain due to fissures or cracks that commonly form in the center of the plaques.
The lesions in the skin folds may present as well-defined dark brown or purplish patches in People of Color. An individual may also notice areas of darker or thicker skin.
Locations
Psoriasis is not contagious. Common areas affected by inverse psoriasis include the armpits, under the breasts, and groin. It can also occur in the genital area.
In the presence of warmth, moisture, and friction, the appearance of the skin changes and may further irritate inverse psoriasis.
Comorbidities
Several other
These include:
- cardiovascular disease
- metabolic syndrome, which includes high blood pressure, obesity, and diabetes
- anxiety and depression
- psoriatic arthritis
- Crohn’s disease
- uveitis
Current guidelines recommend that doctors regularly screen individuals with moderate to severe psoriasis for these and other comorbidities.
A medical professional typically diagnoses psoriasis based on the appearance of the rash, symptoms, personal medical history, and family medical history.
If the lesions occur in an area where the skin rubs against itself, the doctor may diagnose inverse psoriasis.
Doctors may also perform a skin biopsy to confirm the diagnosis and rule out possible fungal infection.
Inverse psoriasis, when left untreated, can lead to infection as well as other possible complications, such as:
- chafing and irritation from heat and sweat
- secondary fungal or yeast infections, particularly Candida albicans
- lichenification or thickening of the skin from rubbing and scratching, particularly around the anus where fecal material irritates the area, causing increased itching
- sexual difficulties because of embarrassment
- thinned skin from the long-term overuse of strong topical steroid creams in the skin folds
Similar to other types of psoriasis, the cause of inverse psoriasis may be multifactorial. There are multiple factors involved in developing psoriasis.
It may have a genetic component that triggers the immune system to become hyperactive, hence it is classified as an immune-mediated inflammatory disorder or an autoimmune disease. In psoriasis, this results in overproduction of skin cells as well as inflammation of other organ systems, usually the joints.
Psoriasis often flares up in response to external factors, such as stress, or internal causes, including an overactive immune system.
What causes a psoriasis flare-up in one person may not affect another.
Triggers
Common triggers include:
Research has not yet identified other possible triggers, which may include allergies, diet, or even weather conditions.
Inverse psoriasis shares similar symptoms with other skin conditions. Below are some that doctors may also consider.
Inverse psoriasis vs. jock itch
Both conditions tend to cause itchy, scaly patches in moist areas, such as the groin.
However, the rashes in inverse psoriasis can often appear shiny and smooth, while jock itch rashes are circular, half-moon rashes that peel, scale, or flake. Additionally, jock itch is caused by a fungal infection, rather than immune dysfunction.
Inverse psoriasis vs. intertrigo
Another rash that occurs in similar locations to inverse psoriasis is intertrigo. Intertrigo is an overgrowth of yeast, Candida albicans, on the skin and causes scaly, itchy, or tender patches where there is a moist environment.
Similar to inverse psoriasis, intertrigo affects the skin in warm, moist areas.
Intertrigo is more
- diabetic
- residing in hot and humid climates
- confined to bed
- elderly
Inverse psoriasis vs. Darier disease
Darier disease is a rare autosomal dominant genetic disorder. It typically presents with scaly, crusted, and raised areas on the scalp, upper chest, back, and skin folds.
Unlike inverse psoriasis, Darier disease usually causes lesions that are the same color as a person’s skin. It may also cause a heavily crusted rash similar to seborrheic dermatitis.
Inverse psoriasis vs. Hailey-Hailey disease
Another condition that can appear like inverse psoriasis is Hailey-Hailey disease.
Hailey-Hailey disease is a rare genetic disorder characterized by the development of blisters and erosions. It often affects the neck, armpits, skin folds, and genitals.
Unlike inverse psoriasis, which has well-defined patches, Hailey-Hailey disease lesions may develop a yellow crusty overlying layer.
Treating inverse psoriasis can be challenging because it typically occurs in areas where the skin is thin and sensitive.
Prescription topicals
The most frequent treatment option for psoriasis is topical steroids. Corticosteroids control inflammatory responses and help reduce swelling and redness caused by plaques.
Doctors often prescribe topical steroids used short term to decrease inflammation.
Low-strength steroids are suitable for treating inverse psoriasis in the groin and under the breasts. However, doctors will recommend people use these with caution as the risk of side effects is greater in sensitive skin areas, where they can cause the skin to thin.
More
- topical calcineurin inhibitors (pimecrolimus or tacrolimus)
- topical vitamin D analogs (calcipotriene and calcitriol)
- phosphodiesterase (crisaborole)
- antiseptics
Potential side effects of topical steroids include:
- skin thinning
- skin pigmentation changes
- easy bruising
- stretch marks
- dilated surface blood vessels
OTC topicals
Mild topical steroids are available over-the-counter (OTC), which can help reduce discoloration and swelling.
The Food and Drug Administration has approved two ingredients to treat psoriasis. Products usually contain salicylic acid and coal tar. Other products may include aloe vera and zinc pyrithione, which help to moisturize, soothe, remove scales, or relieve itching.
Systemic treatment
A systemic medication works throughout the body. People use these drugs for moderate to severe psoriasis or when topical medication and light therapy are ineffective.
Doctors prescribe this type of medication, which can be administered at home. Examples include methotrexate, cyclosporine, apremilast, and mycophenolate mofetil.
These medications all suppress the immune system, and a doctor will monitor a person through regular blood tests.
Biologics
On the other hand, biologics are monoclonal antibodies that target a specific part of the immune system.
Depending on the biologic a doctor prescribes, a person can usually administer the treatment at home via self-injection.
A person should speak with a doctor to discuss all possible risks, side effects, and benefits of biologics.
Hygiene and self-care can help manage the symptoms and improve the appearance of psoriatic patches.
Suitable home-care practices include:
- taking only one bath or shower a day
- regular bathing with lukewarm water
- using a gentle, moisture-rich soap for sensitive skin
- washing the skin very gently with the hands instead of a washcloth
- rinsing off soap or cleanser gently
- drying skin gently
- applying fragrance-free moisturizer within 5 minutes of taking a shower or bath
Itching can be a problem for people with psoriasis. Several OTC anti-itch and cooling lotions are available to relieve these symptoms. Antihistamine drugs can also relieve itching.
Most people with psoriasis find that the sun helps to improve the appearance of their skin. However, due to the location of inverse psoriasis lesions, the sun will not help and may actually aggravate symptoms due to excessive sweating.
A person can take certain measures to help prevent flares of inverse psoriasis. These include:
- using mild, fragrance-free antiperspirants, soaps, and body washes
- reducing friction when exercising by wearing loose clothing
- applying petroleum jelly or talcum powder to genital areas, armpits, or under the breasts to avoid irritation
- washing sweaty areas, with a focus on the groin and genitals, with mild soap and water, and gently patting or blotting dry
- keeping the environment cool to prevent excessive perspiration
- avoiding certain foods that may be a trigger for psoriasis symptoms
- avoiding stress, where possible
- being aware of illnesses that may trigger flares
Whenever there is a change in the skin, a doctor should evaluate it and treat it appropriately to reduce the risk of infection or other complications. People with psoriasis should see a doctor regularly as the condition causes systemic inflammation, such as cardiovascular issues.
The symptoms of psoriasis often resemble those of an infection.
People who are aware of their psoriasis may not need to consult a doctor every time they experience a flare, especially if they are already taking medication and are familiar with their condition.
However, if psoriasis worsens, does not respond to current treatment, or there are signs of an infection, a person with psoriasis should consult a doctor.
Inverse psoriasis can be difficult to treat in some cases, but certain lifestyle changes and topical medications can help control the symptoms.
It is important for people with inverse psoriasis to stay in touch with a doctor, especially if they have a flare-up that does not respond to prescribed medications.
It may also be helpful for people to avoid triggers that aggravate symptoms, such as certain foods or hygiene techniques.