If left untreated, patients with psoriasis may progress to develop psoriatic arthritis, joint erosions, and conjunctivitis. Common complications of psoriasis include depression, psoriatic arthritis, chronic inflammatory bowel disease, non-alcoholic fatty liver disease, celiac disease, sensorineural hearing loss, osteopenia, and osteoarthritis. Psoriasis is a life-long disease that involves multiple relapses and remissions, though symptoms can be controlled with proper medication.

The natural history of psoriasis differs according to the clinical sub-type. The symptoms of psoriasis usually develop in the second decade of life, beginning with such symptoms as skin lesions characterized by erythema and scales covering the lesions. The chronicity of psoriasis may cause significant distress for the affected patient, which can lead to a decrease in the patient’s quality of life.^[1]

• Plaque-type psoriasis is a chronic condition involving multiple relapses and remissions along the course of the disease.
• Extracutaneous involvement is common and the most commonly affected sites include joints and eyes.
• Typical presentation is that of plaques which persist on the same site for months to years, along with an asymmetric oligoarthritis with involvement of the distal (DIPs) and proximal (PIPs) interphalangeal joints of the hands and feet. Erosive joint disease usually develops years after joint involvement.

• Guttate psoriasis presents with spontaneous remissions occurring over the course of weeks to months. In adults, the lesions of guttate psoriasis may become chronic and progress to plaque-type psoriasis.
• It may be aggravated by extrinsic factors such as smoking, excessive alcohol use, pregnancy, HIV infection, and stress.

• Generalized pustular psoriasis is a severe form of psoriasis that can be triggered by:^[2]
  • Pregnancy
  • Rapid withdrawal of corticosteroids
  • Infections
  • Hypocalcemia

Psoriatic arthritis goes through the following stages of progression during its course, defined by the change in clinical damage:^[3]

• Stage 1:
  • Reflects no damaged joints
• Stage 2:
  • One to four damaged joints
• Stage 3:
  • Five to nine damaged joints
• Stage 4:
  • More than 10 joints

Individuals with psoriasis may develop the following complications:^[4]

• High-output cardiac failure in erythroderma^[5]
• Psoriatic arthritis
• Infections
• Cachexy
• Amyloidosis

• Anti-TNF medications given during the management of psoriasis may lead to:
  • Progressive multifocal leukoencephalopathy
  • Optic neuritis
  • Transverse myelitis
  • Multiple sclerosis
  • Infections

• Psoriasis is a lifelong condition.^[6] There is currently no cure but various treatments can help to control the symptoms.
• Many of the most effective agents used to treat severe psoriasis carry an increased risk of significant morbidity including skin cancers, lymphoma, and liver disease. However, the majority of people’s experience of psoriasis is that of minor localized patches, particularly on the elbows and knees, which can be treated with topical medication.
• Psoriasis does get worse over time but it is not possible to predict who will go on to develop extensive psoriasis or those in whom the disease may appear to vanish. Individuals will often experience flares and remissions throughout their lives.
• Controlling the signs and symptoms typically requires lifelong therapy.
• Psoriasis is linked to 2.5-fold increased risk for non-melanoma skin cancer in men and women, with no preponderance of any specific histologic subtype of cancer.^[7]

The Primary Care Dermatology Society and the British Association of Dermatologists suggests that the following groups of patients may require secondary care:^[8]

• Diagnostic uncertainty
• Request for further counseling or education, including demonstration of topical treatment
• Failure to respond to appropriately used topical therapy for three months
• Psoriasis at sites that are difficult to treat (scalp, face, palms, soles, genitals) if unresponsive to initial therapy
• Adverse reactions to topical therapies
• Need for systemic therapy and phototherapy
• Disability preventing work or excessive time off work
• Acute unstable psoriasis
• Erythrodermic or generalized pustular psoriasis (emergency referral indicated)