Comparison of Growth ofMycoplasma Pneumoniaeon Modified New York City and Hayflick Media

Sandy A. Dorman, Deborah J. Wilson, Thomas F. Smith
1983 American Journal of Clinical Pathology  
Modified New York City medium was compared to Hayflick solid medium without methylene blue, using 23 stock strains of Mycoplasma pneumoniae. Time to recovery was the same for both media, never longer than 24 hours. Sensitivity, as measured by colony counts, was significantly greater with Hayflick medium. Modified New York City medium may not be more rapid than Hayflick medium and may not offer significant advantages over the latter. (Key words: Mycoplasma pneumoniae; Hayflick medium; Modified
more » ... medium; Modified New York City medium) Am J Clin Pathol 1983; 79: 235-237 MYCOPLASMA PNEUMONIAE INFECTIONS occur in epidemic cycles every two to six years and account for 6-20% of all pneumonias with peak incidence in school-aged children. 2,46 Infection rates in closed populations, such as military recruits and college students, are much higher, approaching 50%.' The laboratory diagnosis of M. pneumoniae infections by cultural technics is hampered by the fastidious growth requirements of the organism, often needing 10 days or more for detection on agar media. 5 A recent study reported the detection of M. pneumoniae five to six days sooner by using modified New York City medium (MNYC) as compared with the conventional medium described by Hayflick. 3 With the promise of increasing the clinical relevance of the laboratory diagnosis of M. pneumoniae infections, we conducted a similar study. Our results, in contrast, revealed that the number of colonies were increased on the Hayflick medium versus MNYC medium, and furthermore, the time to detect growth was not significantly different. Materials and Methods Modified New York City medium consisted of a phosphate-buffered proteose peptone-cornstarch agar base supplemented with agamma horse serum, yeast dialysate, dextrose, lyncomycin hydrochloride, colistin, am-
doi:10.1093/ajcp/79.2.235 pmid:6401916 fatcat:22h43abtnrhrfb6kl4wizkdwmi