Background Frequently, patients with osteoarthritis (OA) are misdiagnosed as rheumatoid arthritis (RA) in primary care centers, leading to wrong treatment and consequent clinical and health economics impact.
Objectives The objective of this study was to describe demographic and clinical characteristics of a cohort of patients derived to a specialized RA center with presumptive RA diagnosis and finally diagnosed as osteoarthritis.
Methods A descriptive cross sectional study. Patients were referred and assisted to a specialized RA center in a 36 month period with presumptive diagnosis of rheumatoid arthritis. Each patient was evaluated to confirm or rule-out diagnosis of RA as follows: a rheumatologist fulfilled a complete medical record, including joint counts; it was assessed rheumatoid factor and anti-citrullinated antibodies, and other laboratories depending on each case. Also were made x-rays of hands and feet, and in some cases of persistent doubt about the diagnosis was requested comparative MRI of hands or/and feet. Frequencies and percentages were calculated for the demographic and clinical characteristics of the cohort of patients in which the diagnosis of RA was ruled-out.
Results From a total of 4780 Patients derived to specialized in RA center with presumptive RA diagnosis, after medical and laboratory evaluation 1875 (39.3%) had a wrong RA diagnosis; of them 1108 patients (59.1%) had finally osteoarthritis diagnosis. Of these patients 783 (70.6%) were women and 325 (29.3%) men, with an average age of 57.4 (±12 years). Majority of these patients were followed by general physicians or internists and treated with non-biologic and biologic disease modifying anti-rheumatic drugs (DMARDs) in the past years, for an average time of 4.5 years.
Conclusions In this cohort of patients the most frequent diagnosis of patients misdiagnosed with RA was osteoarthritis, being more than two thirds of them, predominantly women. This shows the need for the implementation of specialized clinics in RA and educational strategies for primary care physicians in order to avoid the impact of this wrong diagnosis.
Disclosure of Interest None declared