Mycoplasma pneumoniae associated arthropathy: confirmation of the association by determination of the antipolypeptide IgM response.

The association of Mycoplasma pneumoniae with arthropathy in children and young adults has been established essentially on the basis of complement fixation (CF) serology. Because the CF test may be nonspecific for M. pneumoniae, we have confirmed the association by determination of IgM ELISA and IgM and IgG immunoblotting responses in 2 children. Mycoplasma pneumoniae should be considered in any patient with acute respiratory illness who subsequently develops arthropathy.