It is also known as flexural psoriasis orintertriginous psoriasis.
Inverse psoriasis is rare, accounting for 3% to 7% of allpsoriasiscases.
Because these areas rub together often, skin cells naturally slough off before patches can become scaly.
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Location
Inverse psoriasis appears where skin touches skin, like the armpits.
This also differentiates it from plaque psoriasis, which often affectsextensor surfaceslike the kneecap.
Why Is It Called Inverse Psoriasis?
Inverse psoriasis is so-named because it occurs opposite the places whereplaque psoriasisdoes.
Causes
Inverse psoriasis, like all other forms of psoriasis, is an inflammatoryautoimmune disease.
The inflammation causes still-maturing skin cells, calledkeratinocytes, to develop at an extremely fast rate.
When this happens, the affected skin will thicken and form the lesions recognized as psoriasis.
Is sex safe with inverse psoriasis on my genitals?
If you have a psoriasis flare on your genitals, sex may cause pain or discomfort.
Sexual lubricants and condoms may ease discomfort, pain, or itching.
What Triggers Inverse Psoriasis?
Little is known about why inverse psoriasis presents in the way that it does.
Psoriasis, in general, is believed to be triggered by a combination of genetic factors and environmental triggers.
These are known to release inflammatory proteins calledcytokinesthat maytrigger a flarein fatty tissue.
Others believe that theKoebner phenomenonplays a part.
Diagnosis
There are no lab tests or imaging studies that can definitively diagnose inverse psoriasis.
The diagnosis is primarily based on a visual examination of the skin and a review of your medical history.
If in doubt, a dermatologist may perform askin biopsyfor evaluation under the microscope.
Unlike normal tissue, psoriatic tissue will appear hyperplastic (thickened) withacanthotic(compressed) cells.
Considering Other Possibilities
Other conditions can be mistaken for inverse psoriasis.
A healthcare provider will consider all other possible causes to ensure that the appropriate treatment is delivered.
Many of these are thesame treatmentsused for other forms of psoriasis.
You will also want to take steps toavoid known triggers.
Oral versions may be used in extreme cases.
These drugs are not used to prevent disease due to the risk of drug resistance.
In people with inverse psoriasis, the oral antibiotic Aczone (dapsone) appears especially effective.
It is typically prescribed in a 100-milligram (mg), once-daily dose until the infection resolves.
This might include the armpits, groin, or folds of skin under the breasts or on the abdomen.
Lesions are red, smooth, shiny, and itchy.
Your healthcare provider may recommend topical creams, injectable medication, or lifestyle changes to help manage the condition.
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