Determining early referral criteria for patients with suspected inflammatory arthritis presenting to primary care physicians: a cross-sectional study

Abstract

Objective: Early diagnosis and initiation of treatment for inflammatory arthritis can greatly improve patient outcome. We aimed to provide standardized and validated criteria for use by primary care physicians (PCPs) in the identification of individuals requiring referral to a rheumatologist.

Patients and methods: We analyzed the predictive value of a wide variety of demographic variables, patient-reported complaints, physical examination results, and biomarkers in order to identify the most useful factors for indicating a requirement for referral. Patients for this cross-sectional study were enrolled from various centers of the city of Jeddah, Saudi Arabia, if they were ≥18 years of age and presented to a PCP with small joint pain that had been present for more than 6 weeks. A total of 203 patients were enrolled, as indicated by the sample size calculation. Each patient underwent a standardized physical examination, which was subsequently compared to ultrasound findings. Biomarker analysis and a patient interview were also carried out. Results were then correlated with the final diagnosis made by a rheumatologist.

Results: A total of 9 variables were identified as having high specificity and good predictive value: loss of appetite, swelling of metacarpophalangeal joint 2 or 5, swelling of proximal inter-phalangeal joint 2 or 3, wrist swelling, wrist tenderness, a positive test for rheumatoid factor, and a positive test for anti-citrullinated protein antibodies.

Conclusion: Nine variables should be the basis of early referral criteria. It should aid PCPs in making appropriate early referrals of patients with suspected inflammatory arthritis, accelerating diagnosis and initiation of treatment.

Keywords: diagnosis; early referral criteria; inflammatory arthritis; primary care; rheumatoid.

Figure 1

Study design. Abbreviations: CPR, C-reactive protein; RF, rheumatoid factor; ESR, erythrocyte sedimentation rate; Hep, hepatitis; ANA, antinuclear antibody; AST, aspartate aminotransferase; ALT, alanine aminotransferase; ACPA, anti-citrullinated protein antibodies; US, ultrasonography.

Figure 2

Standardized musculoskeletal examination procedures. Note: The described techniques for physical examination should be performed by a trained clinician. Abbreviations: MCP, metacarpophalangeal; PIP, proximal inter-phalangeal.