EXPERIENCE WITH NEWER TECHNIQUES FOR THE LABORATORY DETECTION OF MYCOPLASMA-PNEUMONIAE INFECTION - ADELAIDE, 1978-1992

Efforts to improve laboratory diagnostic methods for infection due to Mycoplasma pneumoniae have involved the use of a cell-sheet culture method and a modified indirect hemagglutination method for IgM antibody, while direct detection of mycoplasma has employed antigen capture-enzyme immunoassay (Ag-EIA) and polymerase chain reaction (PCR) amplification of sequences within the P1 and 16S ribosomal RNA genes and quantification of the amplified DNA by dot blot hybridization (DBH). Cell-sheet culture was slightly more sensitive and more rapid than culture with cell-free diphasic medium. Indirect hemagglutination detection of IgM antibody to M. pneumoniae was more sensitive than CF and EIA for detection of IgM antibody to mycoplasma. Ag-EIA gave a rapid and reasonably sensitive indication of infection and correlated well with a serological response of patients indicating a current infection. PCR-DBH was a highly sensitive substitute for culture of mycoplasma. Both Ag-EIA and PCR-DBH require confirmation by assessment of serological response to verify that the infection is current and that positive results of PCR-DBH, in particular, are not the result of continuing carriage of the organism from a previous infection, unrelated to the current episode under investigation.