Enhanced isolation of Mycoplasma pneumoniae from throat washings with a newly-modified culture medium.

Two hundred throat washings, previously screened and presumed negative for Mycoplasma pneumoniae in conventional mycoplasma culture media, were retested for the organism in a modified medium (PS-4) initially developed for cultivation of a tick-derived Mycoplasma (spiroplasma). The organism was rapidly identified with an agar plate immunofluorescence procedure. M. pneumoniae was isolated from 69 (34.5%) of the 200 "negative" specimens cultured on a diphasic SP-4 medium, in contrast to 10 isolations (5%) made on conventional diphasic mycoplasma medium. This enhanced recovery of M. pneumoniae represented a combination of a superior culture medium and a more efficient identification technique. The findings suggest that these procedures might be effectively applied to the recovery of M. pneumoniae from all likely host and that improved recovery of the organism may aid in the interpretation of a number of puzzling questions about the epidemiology of M. pneumoniae infections.