Introduction
Psoriasis is a chronic, autoimmune disease of skin in which the immune system becomes hyperactive, causing skin cells to proliferate quickly.
It is characterized as scaly and inflamed patches on skin. It is a non contagious disease that often affects the scalp, elbows, or knees, but other parts of the body can be affected as well. While the exact cause of psoriasis is still unknown, it is believed that the etiology of psoriasis involves a mix of genetics and environmental factors.
This disease can be present as a small localized patch or wide spreading all over the body.
Causes:
Psoriasis is an immune-mediated disease. It simply means that our body’s immune system becomes hyperactive and causes damage to the body. The immune cells become active and produce molecules that decrease the rapid production of dermal cells (skin cells). This is the reason behind inflamed and scaly patches on skin.
Some people with psoriasis have a family history of the disease, but the exact cause is still unknown.
Risk factors:
● Infections; for example, upper respiratory tract infection, HIV, streptococcal infection, etc.
● Skin trauma such as cuts, scrapes or surgery
● Certain medicines, for example, Beta blockers, antimalarial drugs, ACE inhibitors, etc.
● Smoking
● Obesity
Signs and symptoms:
The symptoms of psoriasis vary from mild itchiness to severe discomfort and irritating scaly patches on skin. Psoriatic patches and symptoms also vary from person to person.
General symptoms:
● Thick patches on skin
● Reddish skin with silver-white scales that itch or burn, especially on the elbows, knees, scalp, trunk, genitals, lower back, palms, and soles of the feet.
● Cracked skin with dryness that itches or bleeds sometimes
● Thick, ridged, pitted fingernails or toenails
● Poor sleep cycle
The symptoms of psoriasis come and go. There may be a symptom present today, which gets worse, called flares, and suddenly disappears for a few days. Individuals feel symptom free then come again. This is called remission. Therefore, people go through cycles of symptoms.
Psoriasis carries the risk of getting other serious illness as well, including:
● Psoriatic arthritis, resulting in pain, swelling, and stiffness of the joints and areas where the tendons and the ligaments attach to bones (Entheses). Untreated psoriatic arthritis can lead to irreversible damage.
● Cardiovascular diseases, such heart attacks and strokes.
● Mental health problems, such as low self-esteem, anxiety, panic attacks and depression.
Moreover, individuals with psoriasis are likely to get certain cancers, diabetes, metabolic syndrome, osteoporosis, liver disease, and kidney disease.
Mild to moderate injury to the skin can also trigger psoriatic skin changes at that spot. This is called the Koebner phenomenon.
Types :
Plaque psoriasis: Most common type of the disease. Symptoms include raised, red patches of skin, usually symmetrical, that are covered by silver-white scales. These patches more oftenly appear on the scalp, trunk, and limbs, especially the elbows and knees.
Guttate psoriasis: This form appears more commonly in children or young adults. Symptoms include multiple, small, red dots, especially on the torso and limbs. This type is often triggered by an upper respiratory tract infection.
Pustular psoriasis: This type is characterized by pus-filled bumps called pustules surrounded by red skin. These pustules usually have a person's hands and feet.
Inverse psoriasis: This form is characterized as smooth, bright red patches in folds of skin present most often beneath the breasts, in the groin areas or armpits.
Erythrodermic psoriasis: This is an uncommon but a severe type of psoriasis. Symptoms include red, scaly skin over most of the body. It can be triggered by a sunburn or medications, such as corticosteroids. This is a life threatening condition and needs special medical attention immediately.
Pathophysiology:
Psoriasis is an autoimmune disease which is characterized by an abnormally excessive and rapid growth of the epidermal layer of the skin. The pathological events in psoriasis are thought to start with an initiation phase in which an event (skin injury, infection, or drugs related) results in activation of the immune system and then the maintenance phase in which there is chronic progression of the disease. Abnormal increase in skin cells (especially during the wound repair) and an overabundance of skin cells result from the sequence of pathological events.
Skin cells which are generally replaced by new skin cells in 28-30 days, but in psoriasis due to hyperactiveness on immune cells, the skin cells are replaced within 2-5 days. This activity creates scaly patches on the skin.
Diagnosis:
1. Physical Examination:
Diagnosis of psoriasis is symptomatic and typically based on the appearance of the skin. Skin in psoriasis patients appears scaly with erythematous plaques, papules, or patches that may be painful, itch and burn.
2. Histological Examination:
If the clinical diagnosis is uncertain, a skin biopsy is performed to confirm the diagnosis. Biopsied skin shows clubbed epidermal projections that interdigitate with dermis on microscopy.
Epidermal skin tissue affected by psoriasis often has large amounts of CD8+ T cells.
# Differential Diagnosis:
Eczema, pityriasis rosea ( this may be confused with guttate psoriasis), nail fungus ( this may be confused with nail psoriasis) or cutaneous T cell lymphoma.
Management
Managing the triggering factors, such as stress and skin trauma, can help keep the symptoms under control.
The treatment plan of psoriasis depends on the form and severity of disease. Mild psoriasis can be successfully treated with common ointments, while moderate and severe psoriasis may require attention and be treated with pills, injections, or light treatments.
● Topical agents: Topical corticosteroids are the most effective agents & considered first line treatment of psoriasis; for example, hydrocortisone & triamcinolone. Highly potent topical corticosteroids may be helpful in some cases, however, it is suggested to use them for four weeks only at a time and only if other less potent topical treatment options are not working.
● Vitamin D: Along with corticosteroid, vitamin D is considered very effective in case of chronic plaque psoriasis.
● UV phototherapy: UV Phototherapy in the form of sunlight has been used for this disease for a long time. The exposure time of UV light should be controlled to avoid overexposure and burning of the skin. The dose is slightly increased in every treatment to let the skin get used to the UV light.
● Systemic agents: Systemic agents including medications by mouth or injectable treatments are used in these patients when topical agents and phototherapy is not working. Systemic agents may include Methotrexate, cyclosporine, acitretin, etc. Methotrexate and cyclosporine suppress the immune system. The majority of patients experience a recurrence of psoriasis after systemic treatment is discontinued.
● Surgery: Rarely surgery is needed in this disease. Limited evidence suggests removal of the tonsils that benefit patients with chronic plaque psoriasis, guttate psoriasis, and palmoplantar pustulosis.
Most of the individuals having psoriasis have very mild skin lesions that are efficiently treated by topical agents including creams or ointments. Depending upon the severity of the lesion, patients may experience significant irritation and discomfort affecting the quality of life. Patients may find difficulties while performing basic physical activities such as playing sports, walking, etc when lesions are present on their palms and soles of feet. Lesions present on the scalp can be particularly embarrassing, as flaky plaque in the hair can be mistaken for dandruff and look unaesthetic.
Psoriatic patients usually feel self-conscious about their appearance. Psoriasis has been associated with low self confidence, anxiety and depression.Psychological distress can result into social isolation and suicidal thoughts.
Frequently Asked Questions (FAQs)
● Who Gets Psoriasis?
Psoriasis is more common in adults as compared to children. However, anyone can get this disease and it affects men and women equally.
● Which part of my body is affected by psoriasis?
Psoriatic patches can be present anywhere on the body but it most often affects the elbow, kee, scalp, palms, feet, lower back, genitals, fingernails and toenails.
● How does psoriasis affect quality of life?
Psoriatic symptoms including itching and burning sensation in skin may interfere with basic functions such as sleeping, doing physical activities including playing sports. Individuals with psoriasis often have low confidence and suffer depression because of their appearance.
● How common is Psoriasis?
Psoriasis is a common skin condition in individuals of the United States. The prevalence of this disease in India is 0.44- 2.8%.
● Is Psoriasis contagious?
No, psoriasis is not a contagious disease. It does not spread from the skin.
● Is Psoriasis curable?
No, psoriasis is not curable but the disease can be controlled with proper management and care.