Management of Sjögren's Syndrome with Inflammatory Polyarthritis

Initial Assessment and Treatment

The European League Against Rheumatism (EULAR) recommends calculating the ESSDAI score to quantify systemic disease severity, guiding treatment intensity 1, 2
Baseline chest radiography and complete pulmonary function tests (PFTs) should be obtained, even without respiratory symptoms, due to the frequent occurrence of subclinical interstitial lung disease in Sjögren's patients 1
High-resolution CT (HRCT) should be performed if respiratory symptoms are present or PFTs are abnormal to identify early ILD 1
Screening for hepatobiliary involvement is necessary, given the elevated GGT and positive mitochondrial antibodies, which may indicate overlap with primary biliary cholangitis 3
The American College of Rheumatology recommends evaluating cytopenias to determine if they are related to active systemic disease, hypersplenism, or medication effects 3

For low disease activity (ESSDAI 1-4), the American College of Rheumatology recommends starting hydroxychloroquine 200-400 mg daily as first-line therapy for fatigue and inflammatory polyarthritis 1, 2
Hydroxychloroquine addresses arthralgias and constitutional symptoms with minimal side effects, according to the European League Against Rheumatism 4, 5
Topical therapies, such as artificial tears and saliva substitutes, should be used to manage sicca symptoms, as recommended by the European League Against Rheumatism 2
Oral muscarinic agonists, like pilocarpine or cevimeline, may be considered if sicca symptoms are inadequately controlled with topical therapy alone, as suggested by the American College of Rheumatology 3

For moderate disease activity (ESSDAI 5-13), the European League Against Rheumatism recommends initiating glucocorticoids at 0.5 mg/kg prednisone equivalent, with a plan for slow taper 1, 2
Mycophenolate mofetil (MMF) 500-1000 mg twice daily or azathioprine 1-2 mg/kg daily should be added as steroid-sparing agents when long-term glucocorticoid use is anticipated, as recommended by the American Thoracic Society 6, 7, 2
MMF is preferred over azathioprine due to a lower risk of drug-induced pneumonitis, according to the American Thoracic Society 6, 7
Thiopurine methyltransferase (TPMT) activity or genotype should be tested before initiating azathioprine to reduce the risk of severe leukopenia, as recommended by the American Thoracic Society 6

Pulmonary function tests (PFTs) should be repeated every 6-12 months to track disease trajectory if baseline abnormalities are present, as recommended by the European League Against Rheumatism 1, 2
If symptomatic ILD with moderate-severe impairment develops, the American Thoracic Society recommends initiating moderate-dose oral corticosteroids (0.5-1.0 mg/kg) plus MMF or azathioprine as first-line therapy 6, 8, 7
For progressive fibrotic ILD, nintedanib should be added as second-line maintenance therapy, as recommended by the American Thoracic Society 8, 9, 7

Therapeutic success is defined as a ≥3 point reduction in ESSDAI score at 3-6 month reassessment, according to the European League Against Rheumatism 1
If there is an inadequate response at 6 months with ESSDAI >11, therapy should be escalated by adding a steroid-sparing agent to hydroxychloroquine or switching to rituximab if already on conventional immunosuppression, as recommended by the European League Against Rheumatism 1, 2
Glucocorticoids should be maintained at the lowest effective dose, ideally below 10 mg prednisone daily, for long-term management, as recommended by the American College of Rheumatology 11, 4, 5, 7