Immunoglobulin E in chronic middle ear effusions: conmparison of RIST, PRIST, and RIA techniques

To investigate the possible role of allergy in otitis media with effusion (OME), the immunoglobulin E (IgE) content of 138 middle ear effusions (MEE) and paired serum samples from patients with chronic otitis media with effusion was determined. The initial 62 paired specimens were assayed for IgE by the radioimmunosorbent test (RIST), while the later 76 paired specimens were assayed for IgE by the paper radioimmunosorbent test (PRIST). When the results obtained by these two techniques were compared, it was noted that the PRIST procedure gave significantly lower IgE values for effusions than the RIST method. When the effusion-to-serum ratios (E/S ratios) were computed from the PRIST data, the E/S ratio was less than one, while RIST data gave an E/S ratio greater than one. The results obtained with the PRIST procedure were confirmed by double antibody radioimmunoassay for IgE. Thus, the PRIST procedure appears to measure the IgE content of MEE more accurately, and the results obtained by this procedure fail to support the concept of allergy as a major causative factor in OME.