Psoriasis is a chronic inflammatory skin disease. It presents with well defined, red and scaly plaques more commonly on scalp, elbows and knees. However, any part of the skin can be involved. The worldwide prevalence is 1–3% of males and females.
Psoriasis is multifactorial. It has a genetic component but also shows clear autoimmune-related pathophysiology. Factors that aggravate psoriasis include streptococcal infections, injuries, sun exposure, obesity, excessive alcohol, stressful events and medications.
Typical patterns of psoriasis include:
- Chronic plaque psoriasis: It is the most common type, presented with sharply demarcated, erythematous, pruritic plaques covered in silvery scales.
- Guttate Psoriasis: It usually affects children or adolescents following group-A streptococcal infections. Presents with widespread small plaques which often resolves after few months. Patients with history of guttate psoriasis are in risk to develop plaque psoriasis throughout their adult life.
- Flexural psoriasis: It is also called inverse psoriasis and describes psoriasis localised to armpits, groin, under the breasts, umbilicus and genitals. It presents with shiny and smooth plaques or patches without scales.
- Pustular psoriasis: It is characterized by multiple, coalescing sterile pustules. It can be localized (palmoplantar) or generalized.
- Erythrodermic psoriasis: It may or may not be preceded by another form of psoriasis. It is an acute condition in which over 90% of the total body surface is inflamed and requires emergency treatment.
- Nail psoriasis: Clinical signs include pitting, onycholysis, yellowing and ridging. It is often linked to psoriatic arthritis.
Psoriatic arthritis is a painful, inflammatory condition of the joints. Its prevalence among patients with psoriasis range between 15 and 25%. It presents with axial joint inflammation, asymmetric oligoarthritis (most commonly lower extremities) and dactylitis-swollen fingers or toes that look like sausages. As it may result in joint deformity and morbidity, early and aggressive treatment is required.
Treatment options for psoriasis include topical, ultraviolet, systemic non biological and systemic biological treatment. The goal for patients who desire resolution of their skin lesions is to achieve minimal to no skin involvement with a well-tolerated treatment regimen. Treatment approach is based on several factors such as disease severity, relevant comorbidities and patient preferences.