Psoriasis

Psoriasis typically looks like red or pink areas of thickened, raised, and dry skin. It classically affects areas over the elbows, knees, and scalp. Essentially any body area may be involved. It tends to be more common in areas of trauma, repeat rubbing, use, or abrasions.

Psoriasis has many different appearances. It may be small flattened bumps, large thick plaques of raised skin, red patches, and pink mildly dry skin to big flakes of dry skin that flake off.

Sometimes pulling of one of these small dry white flakes of skin causes a tiny blood spot on the skin. This is medically referred to as a special diagnostic sign in psoriasis called the Auspitz sign. Genital lesions, especially on the head of the penis, are common. Psoriasis in moist areas like the navel or area between the buttocks (intergluteal folds) may look like flat red patches. These atypical appearances may be confused with other skin conditions like fungal infections, yeast infections, skin irritation, or bacterial Staph infections.

On the nails, it can look like very small pits (pinpoint depressions or white spots on the nail) or as larger yellowish-brown separations of the nail bed called “oil spots.” Nail psoriasis may be confused with and incorrectly diagnosed as a fungal nail infection.

On the scalp, it may look like severe dandruff with dry flakes and red areas of skin. It may be difficult to tell the difference between scalp psoriasis and seborrhea (dandruff). However, the treatment is often very similar for both conditions.

The real cause of Psoriasis is still unknown. However, the experts believe lots of factors behind it. Psoriasis becomes more complex when it occurs with some pre-existing diseases.

There are two main hypotheses about the process that occurs in the development of the disease. The first considers psoriasis as primarily a disorder of excessive growth and reproduction of skin cells. The problem is simply seen as a fault of the epidermis and its keratinocytes. The second hypothesis sees the disease as being an immune-mediated disorder in which the excessive reproduction of skin cells is secondary to factors produced by theimmune system. T cells, a type of white blood cell, usually protect the body against infection and disease by attacking bacteria and viruses. However, when you have psoriasis, your T cells mistakenly attack your skin cells instead. Your body then produces other immune system responses, leading to swelling and rapid production of skin cells. Psoriasis tends to run in families and it usually appears between the ages of 10 and 45.

Psoriasis is an inherited disease. However there are certain triggering factors such as injury to the skin, vaccinations and certain medications that have been responsible for the development of this condition. It usually takes about a month for new cells to move from the lower layers of the skin to the surface. In psoriasis, this process takes only a few days, resulting in a buildup of dead skin cells and formation of thick scales.

Psoriasis occurs more likely in dry skin than oily or well-moisturized skin. Excessive alcohol consumption, obesity, lack of or overexposure to sunlight, stress, cold climate, physical illness, streptococcal or HIV infection, superficial wounds, or taking certain drugs such as lithium, beta-blockers such as propranolol, anti-malarial medications and in general poor health results in flaring up of psoriasis.

The symptoms of psoriasis can manifest in a variety of forms. Different types of psoriasis exhibit different characteristics that may change over time. One form may change to another, or several forms may exist at the same time.

• Plaque psoriasis: This is the most common type of psoriasis. It is characterized by raised, red lesions covered with silvery white scales. The scales are caused by a building up of dead skin cells. It may appear on the knees, elbows, scalp, trunk or any other skin surface.
• Guttate psoriasis: It is characterised by numerous small red dots of psoriasis. The lesions may have some scaling. These numerous spots of psoriasis appear over large areas of the body, such as the trunk, limbs, and scalp. It may appear suddenly following a bacterial or viral infection or the administration of drugs like ketoconazole and salicylic acid.
• Inverse psoriasis: This is usually found in the folds of the skin in the armpits, groin, under an overweight stomach or under the breasts. It appears as smooth, red lesions without scaling and may cause irritation due to rubbing and sweating.
• Pustular psoriasis: It is characterized by blisters filled with pus on the skin. The blisters are not infectious. It may be found on the hands and feet or may be spread all over. The skin under and surrounding pustules is red and tender.
• Psoriatic arthritis: About 10% to 30% of the patients with psoriasis may develop a form of arthritis called psoriatic arthritis. This may cause redness and swelling, primarily on the hands, feet, knees, hips, elbows and spine. It may cause stiffness, pain and joint damage.
• Nail psoriasis: produces a variety of changes in the appearance of finger and toe nails. These changes include discolouring under the nail plate, pitting of the nails, lines going across the nails, thickening of the skin under the nail, and the loosening and crumbling of the nail.
• Erythrodermic psoriasis: involves the widespread inflammation and exfoliation of the skin over most of the body surface. It may be accompanied by severe itching, swelling and pain. It is often the result of an exacerbation of unstable plaque psoriasis, particularly following the abrupt withdrawal of systemic treatment. This form of psoriasis can be fatal, as the extreme inflammation and exfoliation disrupt the body’s ability to regulate temperature and for the skin to perform barrier functions.