Diagnostic Value of Short Course Low-dose Prednisolone in Patients with Clinically Suspected Seronegative Inflammatory Arthritis - A Retrospective Study.

Objective: We aim to establish the utility of a trial of low-dose systemic glucocorticoid therapy in the assessment of new clinically suspected inflammatory arthritis patients.

Methods: We retrospectively identified patients from a private rheumatology practice in Melbourne, Australia between January 1st, 2019, and December 31st, 2021, who presented with clinically suspected inflammatory arthritis and subsequently underwent a trial of low-dose prednisolone (15 mg daily weaned over three weeks in 5 mg increments). We excluded patients with known autoimmune/ inflammatory disorders or concurrent immunosuppression at presentation. We collected basic participant demographic details and clinical details of their presentation, glucocorticoid response, investigations, and treatment.

Results: We recruited 177 participants with a median age of 52, and 69.5% were female gender. The median symptom time to presentation was 12 months. Hands were the most affected joint in 63.3% and 85% had bilateral disease. Among the participants, 29.4% had synovitis on clinical review and 75.7% had imaging performed as part of the initial assessment. At presentation, the median CRP was 11 and the median ESR was 16. 79.7% of the cohort experienced significant improvement in their arthritis symptoms from low-dose glucocorticoids and 83.6% of the cohort required long-term immunosuppression for an underlying inflammatory condition. Of those who responded to glucocorticoids, 92.1% were diagnosed with an inflammatory condition. Rheumatoid arthritis was the most common overall diagnosis in 28%.

Conclusion: An initial trial of low-dose glucocorticoids in undifferentiated arthritis patients is useful in predicting the diagnosis of inflammatory arthritis. It is also a predictor of further long-term steroid-sparing therapy.