What is the initial management for a 14-year-old patient with bilateral sacroiliitis?

Initial Management of Bilateral Sacroiliitis in a 14-Year-Old

Start with NSAIDs as first-line therapy for bilateral sacroiliitis in this adolescent, as this provides both analgesic and anti-inflammatory benefits and is the strongly recommended initial treatment according to the American College of Rheumatology. 1, 2

Diagnostic Confirmation and Assessment

Before initiating treatment, confirm the diagnosis and assess disease activity:

• MRI findings should demonstrate bone marrow edema consistent with active sacroiliitis, along with clinical examination findings (pain with direct palpation of sacroiliac joints) and/or inflammatory back pain 1
• Assess disease activity using the clinical Juvenile Arthritis Disease Activity Score (cJADAS-10), where >2.5 indicates moderate/high disease activity and ≤2.5 with ≥1 active joint indicates low disease activity 1
• Laboratory evaluation including ESR and CRP helps assess inflammation, though elevation of inflammatory markers does not always correlate with MRI findings of bone marrow edema 3
• Consider underlying diagnosis as bilateral sacroiliitis in this age group typically represents enthesitis-related arthritis, psoriatic arthritis, or undifferentiated juvenile idiopathic arthritis 1

First-Line Treatment: NSAIDs

NSAIDs are strongly recommended as initial monotherapy over no treatment for active sacroiliitis 2:

• Use optimal anti-inflammatory doses rather than just analgesic doses 2
• Evaluate clinical response after 2-4 weeks of therapy 2
• Continue for adequate trial period while monitoring for symptom improvement 1

Adjunctive Therapies During Initial Treatment

Physical therapy is conditionally recommended for patients who have or are at risk for functional limitations, to maintain range of motion and strengthen periarticular muscles 1, 2

Bridging oral glucocorticoids (<3 months) are conditionally recommended during initiation of therapy if the patient presents with high disease activity, limited mobility, or significant symptoms 1, 2:

• This is short-term bridging therapy only, not long-term monotherapy 1
• Duration must be limited to less than 3 months 2

Intraarticular glucocorticoid injections of the sacroiliac joints are conditionally recommended as adjunct therapy 2:

• CT-guided intra-articular corticosteroid injection has proven effective in children with juvenile spondyloarthropathy who fail to respond to NSAIDs 4
• In one study, 87.5% of children showed significant improvement within 1.5 weeks, lasting a mean of 12 months 4

Escalation Strategy for Inadequate Response

If the patient shows inadequate response to NSAIDs after 2-4 weeks:

Add a TNF inhibitor (TNFi) to the treatment regimen, as this is strongly recommended over continued NSAID monotherapy 2:

• Common TNF inhibitors include etanercept, adalimumab, infliximab, and golimumab 2
• TNFi therapy has demonstrated significant benefit in both pediatric data and adult spondyloarthritis trials 2
• This is conditionally recommended over methotrexate or sulfasalazine for active sacroiliitis despite NSAIDs 1, 2

What NOT to Do: Critical Pitfalls

Do not use methotrexate monotherapy for sacroiliitis, as this is strongly recommended against by the American College of Rheumatology 2:

• Methotrexate may only be useful as adjunct therapy if the patient has concomitant peripheral polyarthritis or to prevent anti-drug antibody formation against monoclonal TNFi 2

Do not use prolonged oral glucocorticoids as monotherapy, as they are only for short-term bridging (<3 months) 1, 2

Do not dismiss the diagnosis without proper MRI evaluation, as radiographic changes may not be evident early in the disease course 1

Alternative Second-Line Options

Sulfasalazine is conditionally recommended only for patients who have contraindications to TNFi or have failed more than one TNFi 2:

• This is not preferred over TNFi as initial escalation therapy 1
• The evidence supporting sulfasalazine is of very low quality 1

Monitoring and Follow-Up

• Regular assessment of treatment response is essential to guide therapeutic decisions 2
• Re-evaluate after 6-8 weeks if no or minimal response is observed, as changing or adding therapy may be appropriate at that point 1
• Follow-up MRI may be considered to assess inflammatory activity, though clinical response is the primary guide for treatment decisions 4
• Note that one-third of patients may show progression of joint destruction despite absence of subjective complaints, highlighting the importance of objective monitoring 4