Efficacy of the enteric pathogen screen card in the presumptive identification of Salmonella enteritidis.

The efficacy of the Enteric Pathogen Screen (EPS) card as a rapid method for identification of Salmonella spp. isolated in stool cultures was studied. Of the 120 lactose-negative, sucrose-negative, H2S-producing colonies tested, 74 were identified as Salmonella enteritidis by conventional methods. The reading of the EPS card after 2 h of incubation yielded a sensitivity of 47.2% and a specificity and positive predictive value of 100%, with a negative predictive value of 54.1%. In the final reading of 4 h, a sensitivity of 97.2% and a specificity of 86.9% were obtained, with a positive predictive value of 92.3% and a negative predictive value of 95.2%.