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Transient rheumatoid factor positivity in acute human parvovirus B19 infection.

The relationship between parvovirus B19 infection and classic rheumatoid arthritis remains to be determined. We describe two adult patients with serologically documented acute parvovirus B19 infection who presented with sudden onset of symmetric polyarthritis, skin eruption, and rheumatoid factor positivity. Rheumatoid factor positivity and symptoms resolved within five months. We conclude that a diagnosis of B19 arthropathy should be considered in any patient with recent acute or subacute onset of symmetric polyarthralgia or polyarthritis and rheumatoid factor positivity, which would otherwise suggest a diagnosis of early rheumatoid arthritis.