We report on a patient with seropositive polyarthritis retrospectively diagnosed as Poncet's disease in the preclinical phase of seropositive rheumatoid arthritis. Our patient developed rheumatoid arthritis more than 2 years after being successfully treated for pulmonary tuberculosis and an initial inflammatory polyarthritis consistent with the diagnosis of Poncet's disease. This case illustrates the importance of recognizing Poncet's disease in a patient presenting with polyarthritis in order to avoid inappropriate long-term disease modifying antirheumatic treatment. It also illustrates the need for adequate follow-up of patients with Poncet's disease after treatment with antituberculosis treatment so that progression to a primary inflammatory arthritis such as rheumatoid arthritis may be identified timeously. Although seropositivity for rheumatoid arthritis has been reported in Poncet's disease as well as in tuberculosis, it is rather uncommon, and long-term follow-up of patients with Poncet's disease is essential particularly if they have positive serological tests for rheumatoid arthritis. In this case report, we describe the first reported case of Poncet's disease in the preclinical phase of rheumatoid arthritis and review the literature related to this rare disease presentation.