Background: Non- typhoidal salmonella infection is a major cause for acute bacterial gastroenteritis in children. There is no ideal method for diagnosis of salmonella infection and the development of highly selective media continues to be of particular importance for diagnostic and treatment purposes. Objective: Was to assess the performance of two media, the first one was the MSRV agar as a screening medium for isolation of salmonella from stool samples of pediatric patients with gastroenteritis and the second medium was the new salmonella single tube to identify Salmonella spp. Methodology: Stool samples were subjected to stool analysis, isolation of Salmonella species on selective culture media (XLD, SS & MSRV). Different biochemical reactions were used to identify Salmonella spp; the first was the conventional biochemical reactions and the second was the newly suggested salmonella single tube. Conventional PCR was done to detect the genus salmonella and the serovars enteritidis and typhimurium. Results: Comparing the results of the three selective culture media, the validity values observed with MSRV medium were superior to those obtained by the other two media. Salmonella single tube yielded 100% sensitivity, specificity, positive predictive and negative predictive values with reliability equivalent to that of the conventional 5 tubes method. Salmonella typhimurium was prevalent in 75% of positive patients while Salmonella enteritidis was detected in 25%. Conclusion: When MSRV agar was evaluated in comparison to other selective media, it had the highest values in terms of performance. Direct plating of MSRV agar produced the same performance of indirect plating therefore, direct plating could shorten the detection time of Salmonella spp. Using salmonella single tube ensures simple and rapid processing in one step and is very suitable for mass screening purposes. |
