Overview
Psoriasis is a chronic inflammatory, hyperproliferative skin disease. It is characterized by well-defined erythematous scaly plaques particularly affecting extensor surfaces, scalp, and nails and usually follows a relapsing and remitting course. It is more common in Caucasians but less common in Asian, South American, and African populations. It occurs in both sexes and at all ages, but less commonly under the age of 5 years. The age of onset follows a bimodal distribution with an early onset type in early adult years, often with a family history of psoriasis, a more severe course, and a strong HLA association. The later onset type is typically seen between 50& 60 years, usually without a family history and with a less severe disease course.
Symptoms
Plaque psoriasis
It is most common presentation and usually represents more stable disease . The lesion is raised , well-demarcated erythematous plaque of variable size.If untreated, silver/white scales are evident and on scraping the surface bleeding points are seen also known as auspitz sign.The most common sites are extensor surfaces, elbows and knees,and the back.The scalp is involved in 60% of cases
Guttate psoriasis
This is most common in adolescent and children and is often an initial presentation.It mostly presents after streptococcal throat infection and evolves rapidly.Individual lesions are droplet-shaped,small, erythematous scaly and numerous
Erythrodermic psoriasis
It is a rare condition forming red rashes all over body which looks like burn and causes severe dehydration ,chills , fever and shock. Thus this is an emergency and requires immediated medical attention .
Pustular psoriasis
It may be generalized or localized .
Geberalised is uncommon , unstable and life threatening .Its onset is usually sudden ,with large number of small sterile pustules on an erythematous background ,often merging into sheets with waves of new pustules in subsequent days .This is a medical emergency and must be dealt immediately .
Whereas, localized pustular psoriasis of the palms and soles is more common .It is a chronic disease and closely associated with smoking . the small , sterile pustule with erythema develop and resolve with pigmentation and scaling .
Causes
Trauma
Infections ( beta hemolytic streptococcal , HIV infection )
Sunlight
Drugs like antimalarials , beta blockers , lithium, NSAIDs , rebound phenomenon after withdrawl of glucocorticoids
Anxiety and stress
Smoking
Complications
Psoriatic arthritis
Uveitis/blepharitis / conjunctivitis
Anxiety & depression
Parkinson’s disease
Hypertension
Cardiovascular diseases
Obesity
Diabetes mellitus 2
Autoimmune disease like SLE , MS , Celiac disease etc
