PARVOVIRUS-B19-INDUCED ARTHRITIS ARTHROPATHY AND ITS IMPORTANCE IN DIFFERENTIAL-DIAGNOSIS OF RHEUMATOID-ARTHRITIS

Introduction/aims: The differential diagnosis of rheumatoid arthritis (RA) and parvovirus-B19-induced arthritis/arthropathy (PEA) can be dif ficult, but is of importance because of the different therapeutic impl ications. The purpose is to describe characteristic features serving t o differentiate between chronic PEA and RA, based on 6 personal cases and the literature. Methods/Patients: 6 patients presenting with acute (3 cases) or chronic PEA (3 cases) over the last 5 years are describe d. Results/conclusions: The demonstration of anti-parvovirus-B19-immun oglobulins (Ig)M in addition to anti-parvovirus-B19-IgG is the most im portant diagnostic finding. Measurement of IgM must be done within the first months after onset, as it disappears later on. Furthermore, his tory of disease (exposure, prodromi and acute onset of arthritis), cli nical examination (rash) and further investigations (normal ESR and CR P, typical hematologic findings, examination of synovial tissue and fl uid without inflammatory changes, demonstration of the genome of parvo virus B19 by polymerase chain reaction, no erosions on radiographs) su pport the diagnosis of PBA. 2 of the 3 patients with chronic PBA fulfi lled the criteria for classification of RA. Therapeutic approaches in PBA are discussed. In contrast to the favourable effect in RA, immunos uppressive agents may prolong persistence of virus and disease in PBA.