Psoriasis is a chronic, autoimmune, inflammatory skin disease that causes red, dry, itchy, raised patches with silvery or white scaly flakes that flake like dandruff which can affect the skin from head to toe, on the elbows, torso, knees, nails, and in the joints. Psoriasis is a chronic skin disease that is treatable but not curable and can lead to other complications such as psoriatic arthritis, autoimmune disease, or metabolic syndrome. Seeing an experienced dermatologist to treat psoriasis at its root source will aid in the control and prevention of the disease.
What causes psoriasis?
The primary cause of psoriasis is immune cells dysfunction, mistaking healthy skin cells for bacteria or viruses. The immune cells stimulate inflammation of healthy skin cells, causing rapid skin cells division and piling up of both new and old skin cells in a thick plaque, resulting in a rash, or psoriatic dermatitis, with shedding of the top skin layers. Other causes and factors that trigger psoriasis include:
- Genetics is one of the underlying causes of psoriasis, with one in three people having a family history of the disease.
- Environmental factors such as hot or cold weather, exposure to bright sunlight, and insect bites.
- Viral infections such as rhinoviruses, human immunodeficiency virus (HIV), human papillomavirus (HPV), and hepatitis C virus (HCV)
- Bacterial infections in the pharynx, such as streptococci, can cause sore throats or tonsillitis.
- Inadequate sleep
- Certain medications, such as beta-blockers, lithium
- A skin injury or post-surgery contact dermatitis
What are the types of psoriasis?
Psoriasis is classified into several types based on the appearance and distribution of the disease, as follows:
- Plaque psoriasis, or psoriasis vulgaris, is characterized by thick, red, slowly expanding lesions with distinct edges and various shapes covered in white or silver flakes on the scalp, torso, elbows, limbs, lower back, knees, and opposing skin areas such as the armpits, under the breasts, and groin. Plaque psoriasis is the most common type, accounting for 80-90% of all cases of psoriasis.
- Guttate psoriasis is psoriasis with red lesions or hard, water-drop-shaped nodules that are less than 1 centimeter in size and flaky white, distributed on the trunk, limbs, and other body parts. A streptococcal throat infection may precede the appearance of guttate psoriasis.
- Pustular psoriasis is a skin condition characterized by numerous small, red, inflamed, non-infectious pustules on top of plaques ranging in size from 2 to 3 millimeters, occurring throughout the skin of the trunk, limbs, palms, soles, and under the nails, causing itching and burning pain. If pustular psoriasis is severe, fever may develop.
- Erythrodermic psoriasis is a severe form of psoriasis, with red, itchy, and flaky lesions covering more than 90% of the body. Erythrodermic psoriasis can be short-term, acute, long-term, or chronic and may develop from any psoriasis type, particularly from worsening of plaque psoriasis with pustules, exhaustion, and associated high fever.
- Inverse psoriasis characterizes by red lesions that appear in patches, are rarely flaky, and occur in opposing skin fold areas that may rub against each other and be sweaty, such as under the breasts, armpits, groin, and buttocks.
- Palmoplantar psoriasis is an erythematous lesion with distinct edges on the palms and soles of the feet. The rash may spread to the back of the hand or the instep.
- Psoriatic nails are psoriasis involving the nail of a finger or toe, causing nail abnormalities such as deformities, cracking, pitting, thickened nails, and skin discoloration around the nail.
- Sebopsoriasisis a psoriatic blister and plaque on the scalp, face, and ears, with a flaky yellow sebaceous, oily plaque similar to seborrheic dermatitis.
What are the symptoms of psoriasis?
The symptoms and severity of psoriasis depend on the type, organs affected, severity, size, distribution, and disease duration. In general, the signs and symptoms of psoriasis are skin rashes or dermatitis patches with the following characteristics:
- Raised lesions with curved, wavy edges and flaking of the uppermost layers, while the underlying layers stick together as a thick plaque.
- Size variations from as small as a drop of water to as big as the palm
- Skin discoloration, such as a purple rash that peels off, white scaly skin, red or pink rash that peels off underlying silver scaly skin.
- Dry, cracked, itchy, or burning lesions.
- Scratching the lesions causes tearing of the plaque and bleeding.
- Severe pain, swelling, and fever.
- Persist for a few weeks to months before subsiding and then reappearing.
How is psoriasis diagnosed?
Dermatologists diagnose psoriasis by taking a medical history and physical examination of the skin, scalp, or nails to assess symptoms, as well as determining the severity of the disease, using the following methods:
- Medical histories: such as when the rash, itching, or burning sensation on the skin first appeared, how much the skin peels or flakes off, most recent illness, the medication you take regularly or recently stopped, regular use of soap or shampoo, has anyone in the same family ever had a history of psoriasis, stress, and other factors that may cause the disease.
- Physical examination: doctors will note the locations, sizes, physical appearance, and the skin surface areas affected by psoriasis.
- Skin biopsy: In addition, dermatologists may do a skin biopsy for pathological examination for further confirmation and identify the type of psoriasis or to rule out the disease by cutting a tiny piece of skin with a blister, rash, chronic wound, abnormally pigmented skin, or peeled skin flakes and examine it under a microscope.
How is psoriasis treated?
The dermatologist prescribes treatment methods based on the type and severity of psoriasis, and its side effects, with the primary goal of controlling and preventing skin cells from dividing too quickly, causing them to pile up, peel, and flake off. For the best treatment results, the dermatologist may combine several treatment methods, including:
- Corticosteroids are available in shampoo, cream, and lotion topical forms for the treatment of mild to moderate face and skin folds psoriasis. Corticosteroids provide good results but should not be a long-term treatment as they can cause skin thinning and suppress adrenal gland function. Their use should be under the supervision of a doctor.
- Calcipotriol is a vitamin D derivative that aids in slowing skin cell turnover and reducing plaque thickness. Calcipotriol is currently used in combination with corticosteroids to improve treatment efficacy. However, this class of drugs should not be used in large amounts to prevent skin thinning and should be under the supervision of a doctor.
- Anthralin and dithranol are tar-based topical creams that are applied to the skin with psoriasis (except the face and genitals) for a short time and then rinsed off, slowing the formation of new skin cells, removing dead skin cells, and making the skin smoother. Caution: the medication may cause skin irritation and darkening of the skin color in the area where it is applied.
- Tar or medications containing tar oil are effective topical ointments. It is now available in many forms, including shampoos, ointments, creams, and lotions, which help inhibit the rapid formation of new skin cells, reduce itching and inflammation, but have a strong odor and cause skin irritation.
- Calcineurin inhibitor is a new class of psoriasis medications, such as topical tacrolimus and pimecrolimus, that help to reduce inflammation and the formation of psoriasis plaques. They can be applied to sensitive skin, such as around the eyes, face, or skin folds, but should not be long-term to reduce the risk of skin cancer or lymphoma. Pregnant or breastfeeding women should not use this medication.
- Skin moisturizer is a fragrance-free, gentle, non-irritating skin ointment with a low risk of allergic reaction. The moisturizer absorbs quickly into the skin, ameliorating itching and burning while moisturizing the skin.
- UVB Light Therapy is a highly safe treatment that uses narrowband ultraviolet B (NB-UVB) artificial sunlight 2-3 times per week for at least three months to alleviate disease symptoms.
- PUVA Therapy: In those with moderate to severe psoriasis, PUVA Therapy is irradiated 2-3 times per week for at least three months in combination with psoralen to slow the formation of new skin cells.
- Excimer light irradiation is a high-efficiency, short-wave ultraviolet (UV 380 nm) irradiation that filters out harmful UV rays and helps balance the function of the body's immune system to treat psoriasis. Excimer light irradiation does not burn or harm the skin during treatment.
Oral and parenteral medications
For those with moderate to severe psoriasis or psoriasis on more than 10% of the skin, including those who have not responded to other therapies, the dermatologist may consider a combination therapy that includes oral and parenteral medications to help improve treatment outcomes.
- Oral medications include methotrexate, acitretin, retinoids, and cyclosporine. However, there may be side effects, and should only be taken under the supervision of a doctor.
- Biologic agents are a new class of drugs that suppress the body's immune system, inhibit the disease cycle, and improve symptoms within 2-3 weeks. The medication may cause side effects from excessive immune suppression. Their uses should be at the doctor's discretion.
What are the complications of psoriasis?
Those with psoriasis are at high risk of developing other diseases or complications, such as:
- Psoriatic arthritis with pain, swelling, and stiffness in the joints, fingertips, or spine.
- Temporary skin color changes.
- Eye diseases such as conjunctivitis, blepharitis, or uveitis
- Type 2 diabetes
- High blood pressure
- Cardiovascular disease, stroke
- Autoimmune diseases such as celiac disease, multiple sclerosis, or Crohn's disease
- Psychiatric disorders such as depression
What are the preventive measures for psoriasis?
There are no foolproof preventions for psoriasis. Regular physical and skin health maintenance, adequate rest, and avoidance of triggers can all help reduce the risk of developing psoriasis. Psoriasis prevention includes the following:
- Apply moisturizer or skin cream to dry and damaged skin to add moisture.
- Always clean your skin regularly.
- Avoid exposure to dry and cold air.
- Avoid medications that can trigger psoriasis.
- Protect the skin from wounds that could become infected.
- Get enough sunlight, but not too much.
- Get sufficient sleep and avoid stress.
Is psoriasis contagious?
Psoriasis is not contagious and cannot be transmitted by touching the blisters or skin rashes of those with psoriasis.
Psoriasis, a manageable chronic skin disease
Psoriasis is a chronic inflammatory skin disease that is manageable, but not yet curable. Treatment takes time and persistent efforts for a good treatment outcome, particularly for those with psoriasis on more than 10% of their skin. Rashes caused by psoriasis can adversely affect one's psyche and personality and may lead to future complications.
Psoriasis requires systematic treatment with single or combination agents prescribed by specialist doctors to alleviate the symptoms, balancing the immune and skin systems to regain normal functions.