What are the other Names for this Condition? (Also known as/Symptoms)

• Flexural Psoriasis
• Intertriginous Psoriasis
• Psoriasis Inversa

What is Inverse Psoriasis? (Definition/Background Information)

• Inverse Psoriasis or Flexural Psoriasis is an uncommon subtype of psoriasis, which is a common chronic inflammatory skin disease that develops from a genetic defect. The condition causes the epidermis to grow abnormally, resulting in the formation of skin lesions. Psoriasis can run in families but is not a contagious condition
• Inverse Psoriasis is a chronic condition that is characterized by well-defined red skin patches in the flexural skin folds, such as at the groin, armpits, or beneath the breasts (where two skin surfaces meet); the skin patches are generally shiny, smooth, and moist
• Some individuals with other subtypes of psoriasis, such as pustular psoriasis, may develop Inverse Psoriasis. The condition is also more common in obese individuals with deeper skin folds. The presentations are known to vary from one individual to another
• It is important to note that all forms of psoriasis are currently incurable. However, the extent and activity of Inverse Psoriasis may be controlled using medications and other treatment measures. The condition may also go into a state of remission, meaning that there may periods when the skin remains normal
• The prognosis of Inverse Psoriasis depends upon its severity and response to treatment. However, it is a lifelong condition that needs to be regularly monitored and treated symptomatically. Inverse Psoriasis can cause long-term emotional and psychological distress

Who gets Inverse Psoriasis? (Age and Sex Distribution)

• About 3-7% of psoriasis cases are predominantly Inverse Psoriasis, although the inverse subtype may be seen with other psoriasis subtypes
• More cases of Inverse Psoriasis are reported in adults than children; according to some reports, the average age of disease onset is 29 years
• Both males and females are affected
• The condition affects all races and ethnic groups. Fair-skinned Caucasians have a generally higher prevalence rate, while dark-skinned individuals are affected to a much lesser extent

What are the Risk Factors for Inverse Psoriasis? (Predisposing Factors)

The following are the risk factors for Inverse Psoriasis:

• Genetic factors: Studies have shown a correlation between psoriasis and individuals with certain types of human leukocyte antigens (HLAs). HLAs are gene complexes that form a part of the immune system
• Certain studies have also demonstrated that individuals with close relatives already affected by the condition are at a higher risk for psoriasis in comparison to the rest of the population. Hence, having a family member with psoriasis is a significant risk factor
• Overweight and obese individuals, especially individuals having multiple deep skin folds at various areas of their body
• Caucasians, who are fair-skinned, are more susceptible to psoriasis
• Individuals having other forms of psoriasis, such as pustular psoriasis, are at an elevated risk for Inverse Psoriasis
• HIV-infected patients
• Individuals who are smokers, diabetic, and with heart disease are at an increased risk for developing severe forms of the condition
• The symptoms may get worse during cold season - during fall and winter

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others. Not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Inverse Psoriasis? (Etiology)

Inverse Psoriasis develops from an abnormal proliferation of the skin cells, referred to as keratinocytes. The exact reason behind this development is unknown. It is believed to be influenced by certain genetic factors.

• There seems to be an association of the skin disorder with a dysfunctional immune system, which results in an abnormally rapid growth of skin cells. The dysfunction does NOT include an increased susceptibility to infections
• It is believed that the condition may be affected by certain environmental factors, such as colder temperatures

What are the Signs and Symptoms of Inverse Psoriasis?

The signs and symptoms of Inverse Psoriasis can vary in type and severity from one individual to another. In some, the symptoms may be mild and involve only a small area of the body surface.

Even in an individual, the symptoms may vary from time to time since the condition waxes and wanes. An early-onset disease is known to develop into a more severe Inverse Psoriasis with a longer course (lasting longer periods).

The signs and symptoms of Inverse Psoriasis may include:

• Well-demarcated red patches around tender skin folds; the patches may be small-sized to covering large skin areas
• The red skin patches are often shiny and moist; hence, scaly, dry skin is not observed in this psoriasis subtype
• There may be cracks in the center of these skin patches; the skin turns thin and is sensitive to friction or break
• The skin folds where the lesions appear commonly include the groin and genitalia, armpits, buttocks (gluteal cleft), perianal skin, and underneath the breasts
• Itchiness and irritability; sweating in these regions may cause further discomfort for the individual

Inverse Psoriasis is a chronic disease that can appear to be improving, but then relapse. This is described as waxing and waning of the condition. Often, the symptoms get better and worse (flare up) over a period of time.

How is Inverse Psoriasis Diagnosed?

Inverse Psoriasis is easily recognized, and a healthcare provider may diagnose the condition on the basis of a thorough physical examination; however, it may be difficult to diagnose mild cases.

A diagnosis of Inverse Psoriasis may involve the following tests and exams:

• Complete physical examination and comprehensive medical history (including evaluation of family history of the condition): A diagnosis of Inverse Psoriasis is normally evident from the location and type of abnormal skin patches
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Bacterial, yeast, and fungal cultures
• X-rays, CT, and MRI scan of the affected joint can help reveal the extent of damage due to inflammation in individuals with psoriatic arthritis
• Skin biopsy: A skin tissue biopsy of the lesions may be performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed), and microscope findings, the pathologist arrives at a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Inverse Psoriasis?

Inverse Psoriasis can cause a variety of complications depending on the severity of the disease activity. Some of these include:

• Psoriatic arthritis may be observed in some individuals with other forms of psoriasis occurring concomitantly
• Severe pain and itchiness of skin leading to acute discomfort and irritation
• Higher susceptibility to bacterial and fungal infections
• Psychological issues such as social anxiety, stress, low self-esteem, depression, and often social isolation
• Due to its chronic nature, some individuals may undergo severe emotional issues and psychological distress that may require counseling
• Embarrassment in public places because of the visible plaques. In many cases, such cosmetic issues may impair one’s daily activities, affecting studies and work
• Severely affected quality of personal life and academic/professional life
• Medication side effects that may be severe in some

How is Inverse Psoriasis Treated?

Inverse Psoriasis is incurable with currently available treatment measures, although the extent of the disease and disease activity can be controlled with suitable medications. The goal behind the treatment is to help control the symptoms, prevent skin infections, and avoid long-term complications.

In general, the following medication/treatment methods are used to manage Inverse Psoriasis:

• Mild to moderate conditions are treated topically by using recommended lotions, corticosteroid creams, or oral steroids to help reduce or control the associated symptoms
  • Since the skin can be very sensitive near the skin folds, it is not advised to use strong creams or use them for a prolonged duration
  • Misuse or overuse of steroid creams and lotions can result in stretch marks and thinning of the local skin
  • Medicated skin areas should not be covered in bandages or other dressings but left open to air
• Use of topical calcipotriene: Calcipotriene, a vitamin D cream or ointment, is particularly well suited for use in Inverse Psoriasis
• When the symptoms flare up, the use of mild-to-moderate corticosteroids is recommended by the National Psoriasis Foundation
• Prescription of antifungal or antibacterial agents, if necessary
• Individuals who are obese may consider suitable weight loss programs and diet regimen

In severe cases of Inverse Psoriasis, the following may be considered:

• Phototherapy includes the use of UVB light (ultraviolet light)
• Biological therapy
• Long-term therapy may include the use of calcipotriene and pimecrolimus or tacrolimus (approved by the US FDA)
• Close monitoring is required to minimize the risk of medication adverse effects

How can Inverse Psoriasis be Prevented?

Currently, there are no preventative measures available for Inverse Psoriasis since it is a genetic condition. Ensuring proper self-care and regular healthcare visits are helpful in mitigating the severity and discomfort.

• Avoiding picking or scratching of the skin (or applying too much pressure on their skin) can help avoid aggravation of the skin lesions
• Avoid exposure to cold temperatures for prolonged periods
• If there is a family history of the condition, then genetic counseling will help assess risks before planning for a child

Active research is currently being performed to explore the possibilities for treating and preventing inherited and acquired genetic conditions.

What is the Prognosis of Inverse Psoriasis? (Outcome/Resolutions)

• The prognosis for Inverse Psoriasis depends on the extent of the condition and severity of signs and symptoms. It is generally good to excellent for mild cases
• In severe cases, the prognosis depends on the set of signs and symptoms. Severe disease can significantly affect one’s quality of overall life and result in long-term stress and depression
• Since the skin condition lasts a lifetime, close monitoring of the symptoms with appropriate treatment will help decrease the burden of the disease

Additional and Relevant Useful Information for Inverse Psoriasis:

• There is no evidence to prove that oily foods and chocolate-based products have an influence on the development of this condition
• Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken to avoid strong soaps and chemicals that could potentially worsen the condition
• The presence of dirt on the body is not a causative factor for the condition. However, it helps to be clean and hygienic, which may help prevent the condition from getting worse