Assessment of gelatin supplementation of PEDS Plus BACTEC blood culture medium

Gelatin supplementation of blood culture media has been shown to neutralize the effects of sodium polyanetholesulfonate and enhance detection of Neisseria species. We evaluated the effect of 1.2% gelatin supplementation of nonradiometric Peds Plus Bactec blood culture medium on the rate and speed of recovery of pathogens from pediatric patients. From June 1991 to June 1992, a total of 6451 paired comparisons of blood cultures in Peds Plus medium and gelatin-supplemented Peds Plus medium were done: 465 organisms were isolated, of which 338 were significant. There were no significant differences in recovery of organisms or the speed of detection of microbial growth between the two media. In particular, the recovery of Neisseria meningitidis (eight isolates) was not improved with gelatin supplementation. In conclusion, gelatin supplementation of Peds Plus Bactec medium does not offer any advantage over the regular Peds Plus Bactec medium.