What is the treatment for psoriatic arthritis?

Treatment for Psoriatic Arthritis

For peripheral psoriatic arthritis, start with NSAIDs for mild disease, rapidly escalate to DMARDs (sulfasalazine or leflunomide preferred) for moderate-to-severe disease, and advance to TNF inhibitors (etanercept, infliximab, or adalimumab) for patients who fail at least one DMARD trial. 1, 2

Treatment Algorithm by Disease Manifestation

Peripheral Arthritis

Mild Disease:

• Initiate NSAIDs as first-line therapy for symptom control 1, 2
• Add intra-articular glucocorticoid injections for persistently inflamed joints (avoid injecting through psoriatic plaques) 1, 2
• Progress to DMARDs if inadequate response after appropriate trial duration 1

Moderate to Severe Disease:

• Rapidly initiate DMARDs - sulfasalazine (Level A evidence) or leflunomide (Level A evidence) are preferred first-line agents 1, 2
• Use methotrexate (Level B evidence) when significant skin involvement coexists 1, 2
• Ciclosporin (Level B evidence) is an alternative option 1
• Avoid gold salts, chloroquine, and hydroxychloroquine - these are not recommended for PsA 1

Refractory Disease (Failed ≥1 DMARD):

• Advance to TNF inhibitors: etanercept 50 mg weekly, infliximab, or adalimumab 1, 2, 3
• All three TNF inhibitors are equally effective for peripheral arthritis and inhibiting radiographic progression 1, 2
• Patients with poor prognostic factors (polyarticular disease, elevated ESR, existing joint damage, diminished quality of life) may warrant TNF inhibitors even without prior DMARD failure 1

Axial Disease (Spondylitis)

Mild to Moderate:

• Start with NSAIDs (Level A evidence) 1, 2
• Add physiotherapy (Level A evidence) 1, 2
• Consider education, analgesia, and sacroiliac joint injections 1

Moderate to Severe (Inadequate Response to NSAIDs):

• Traditional DMARDs (methotrexate, leflunomide, sulfasalazine) are NOT effective for axial manifestations 4
• Advance directly to TNF inhibitors (infliximab, etanercept, or adalimumab) - all have demonstrated efficacy in ankylosing spondylitis and axial PsA 1, 2
• If significant skin involvement coexists, consider IL-17 inhibitors as preferred option over TNF inhibitors 4

Enthesitis

• Mild: NSAIDs, physical therapy, local corticosteroid injections (Level D evidence) 1, 2
• Moderate: Progress to DMARDs (Level D evidence) 1
• Severe/Refractory: TNF inhibitors - infliximab or etanercept have demonstrated efficacy (Level A evidence) 1, 2

Dactylitis

• Initial approach: NSAIDs (Level D evidence) 1
• Persistent inflammation: Rapidly progress to local corticosteroid injections (Level D evidence) 1
• Resistant cases: DMARDs, typically in context of coexisting active disease (Level D evidence) 1
• Severe cases: Infliximab has demonstrated efficacy (Level A evidence) 1

Skin and Nail Disease Management

Moderate to Severe Skin Disease:

• First-line: Phototherapy (UVB/narrowband UVB, oral PUVA, bath PUVA) unless contraindicated (Level A evidence) 1, 5
• Systemic options: Methotrexate, fumaric acid esters, TNF inhibitors (etanercept, adalimumab, infliximab), efalizumab, ciclosporin (all Level A evidence) 1, 5
• Limit ciclosporin to <12 consecutive months due to cumulative toxicity concerns 1
• Second-line: Acitretin (Level A evidence) 1
• Third-line: Alefacept, sulfasalazine, leflunomide (Level A evidence) 1

Nail Disease:

• Options include retinoids, oral PUVA, ciclosporin, TNF inhibitors (infliximab, alefacept) - all Level C evidence 1, 5

Critical Treatment Principles

Assessment Requirements:

• Evaluate 68 joints for tenderness, 66 joints for swelling 1
• Measure acute phase reactants (CRP or ESR) 1
• Assess patient-reported outcomes: pain, global disease activity, physical function (HAQ), quality of life (SF-36 or PsAQoL), fatigue 1
• Monitor for radiographic progression according to clinical judgment 1

Poor Prognostic Indicators Requiring Aggressive Treatment:

• Polyarticular disease (vs. monoarticular) 1, 2
• Elevated ESR 1, 2
• Previous treatment failures 1, 2
• Existing joint damage on radiographs or clinical examination 1, 2
• Diminished quality of life scores 1, 2

Treatment Response Assessment:

• Use DAS28 with EULAR response criteria or ACR20/50/70 criteria 1
• Consider treatment failure when inadequate clinical improvement occurs after appropriate trial duration at appropriate dose 1
• Evidence of radiographic progression constitutes inadequate response 1

Critical Warnings and Contraindications

Systemic Corticosteroids:

• NOT recommended for chronic use in psoriasis - risk of post-steroid psoriasis flare and other adverse effects 1, 5
• Only advisable in discrete circumstances, not for maintenance therapy 1

TNF Inhibitor Safety (from FDA Label):

• Serious infection risk: Test for latent tuberculosis before initiating and during therapy; treat latent TB before starting TNF inhibitor 3
• Monitor closely for invasive fungal infections (histoplasmosis, coccidioidomycosis) - consider empiric antifungal therapy in at-risk patients with severe systemic illness 3
• Malignancy risk: Lymphoma and other malignancies reported, including in children and adolescents 3
• Discontinue if patient develops serious infection or sepsis 3

Phototherapy Precautions:

• Avoid aggressive immunosuppression following extensive PUVA therapy due to increased melanoma and non-melanoma skin cancer risk 1

Treatment Goals

• Aim for remission or low disease activity 2, 4
• Prevent structural joint damage and preserve joint integrity 1, 2
• Maximize health-related quality of life through symptom control and function normalization 4
• Regular disease activity assessment with appropriate therapy adjustment 2, 4