What Causes Psoriasis?
Psoriasis is a chronic skin disease in which patches of red skin, sometimes as wide as 4 inches or more, which have silvery-white flakes and can occur anywhere on the body but most commonly found on the scalp, elbows, knee, lower back, etc. They feel itchy and sore; though the degree may differ from different individuals. Upon scratching the infected skin, it tends to get thicker. It may also crack or bleed. While there is no defined age parameter for getting psoriasis, it usually is seen more in adults than children.
While the exact cause for psoriasis is still not identified by the researchers, most medical experts tend to agree that it is an autoimmune disorder of the body which could have the genetic connection and is usually triggered by environmental factors. There are many common diseases which fall into the category of autoimmune disorders which include Type 1 Diabetes, Rheumatoid Arthritis, Celiac diseases, Anemia, and some types of Thyroid diseases and psoriasis is also one of them.
To understand the cause of psoriasis, it is important to understand the autoimmune disorder. Auto (means self) and immune (body’s natural defense mechanism) is an involuntary complex mechanism of the body which helps it keep the body healthy by fighting off invading and tiny unfriendly microorganisms like bacteria, virus, fungi, etc. The white T cells, normally produced at bone marrow and Thymus gland, are one common type of warrior defense cells of the body to defend the body from these attacks. Under normal conditions, these cells are programmed to identify the intruder or foreign bodies only. Sometimes, this normal programming milieu malfunctions and the immune system cells attack the body’s “own” healthy cells.
The normal life of our skin cells is considered to be 28-30 days. This means that the skin cell’s average life is around 30 days after which it is shed from the skin. Due to the autoimmune disorder, the defense cells identify the healthy skin cells as ‘enemy’ and attacks them. The healthy skin cell is thus destroyed prematurely within 3-4 days only, and the body produces new cells to replace it. Since the skin cannot shed the cells this fast, the prematurely dead skin cells accumulate on the skin surface. The other metabolic and cellular activities like swollen blood vessels in the affected area, dermal stress, etc. cause the skin to appear red and patchy with silvery white scales which forms the basis of diagnosing plaque psoriasis.
There are around 100 genetic combinations identified yet by the scientists that correlate to different types of psoriasis but still the mystery about the exact cause remains to be solved. There are environment factors which have the strong correlation with the triggering of psoriasis in people. A skin injury or surgical cuts along with acute sunburn, dry skin, etc. has also been related to onset of psoriasis. Similarly, infections in the body, particularly with streptococcus bacteria (throat infections) have led to psoriasis. Certain medications like the anti-malarial drug, hypertension drugs, or even stress have also been considered as possible triggers for psoriasis.