Psoriatic arthritis (PsA) is an inflammatory joint disease associated with psoriasis which is a skin disease. PsA affects women and men equally. PsA may occur in up to 30% of patients with psoriasis. Among Malaysian patients with psoriasis, approximately 15-20% have PsA. The arthritis appears after the onset of skin lesions in the majority of patients with PsA. However, the arthritis may precede the skin disease in approximately 13-17% of patients. Undiagnosed arthritis in the presence of skin lesions represents an additional 15%. The extent of skin disease does not generally correlate with the severity of joint disease.

Signs and Symptoms

PsA may present in a variety of joint manifestations. PsA may involve peripheral or limb joints, axial or spinal joints, or both. It frequently presents as polyarthritis (many joint involvement) or less often as oligoarthritis (few joint involvement). Additionally, enthesitis (inflammation at the site of the insertion of tendons, ligaments, and synovium into bone), tenosynovitis (inflammation of the protective sheath around tendons), and dactylitis (swelling of an entire finger or toe, termed a “sausage digit”) may also occur.

Source: www.liberatehealth.us/liberate_condition/psoriatic-arthritis-2/psoriatic arthritis/

Patients with PsA present with pain and stiffness in the affected joints. The joint stiffness is usually worse in the morning and lasts more than 30 minutes. The stiffness is accentuated with prolonged immobility and is alleviated by physical activity. About 70% of patients presenting with arthritis will give a positive history of psoriasis. On physical examination, pain and swelling of the affected joints can be appreciated.

Clinical Patterns of Psoriatic Arthritis

There are five distinct patterns of PsA:

These patterns can often overlap.

Source: http://www.arthritisresearchuk.org/arthritis-information/conditions/psoriatic-arthritis/symptoms.aspx

Investigation

Laboratory findings in PsA are non-specific, reflecting only the typical responses seen in acute as well as chronic inflammation. There are no laboratory findings that are characteristic of PsA, and none to distinguish it from other forms of inflammatory arthritis. However, investigations such as imaging and joint fluid analysis may be performed to exclude other joint diseases including rheumatoid arthritis, osteoarthritis, gout and reactive arthritis.

Treatment

The aim of treating PsA is to control inflammation and to prevent discomfort and damage to the joints. Whenever possible, the treatment should be coordinated between the rheumatologist and the dermatologist since there are differences in response between skin and joints with some agents.

The treatment strategy for PsA should begin with an assessment of the degree of disease activity and damage; referral of all patients for physical and occupational therapy, including exercise instruction, joint protection, and appropriate orthotics; education regarding the disease and the effects of stress on the illness; and instruction in the proper use of topical and oral medications.

Non-steroidal anti-inflammatory drugs (NSAIDs) alone are sufficient for mild disease, but a non-biologic disease-modifying anti-rheumatic drug (DMARD) like methotrexate (MTX) is preferred if the arthritis remains active despite NSAIDs⁵. Leflunomide or sulfasalazine may be used as alternatives to MTX.

Source: Department of Dermatology, Hospital Kuala Lumpur

In patients with joints involvement not improving after treatment with MTX, a treatment with biologics should be considered. The biologics available for PsA treatment include Adalimumab, certolizumab pegol, golimumab (tumor necrosis factor (TNF) inhibitor), Ustekinumab (interleukin(IL) -12/23 inhibitor), secukinumab (interleukin(IL) -17 inhibitor). Use of oral glucocorticoids in patients with PsA should be avoided, except in acute flares of arthritis.

Source: Open access, Google Images

How to prevent deformity

Early recognition and early initiation of treatment is key to preventing joint destruction and subsequent loss of function. This can be achieved with a multidisciplinary strategy of treatment that includes the rheumatologist, dermatologist, physical and occupational therapist, combined with intensive patient education regarding the disease and adherence to treatment.

Reference

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