الفهرس 
Introduction and Aim of workOnly 14 pages are availabe for public view
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Abstract
Staphylococcal enterotoxins (SEs) are potent exoproteins produced by Staphylococcus aureus (S. aureus). To date, 18 SEs have been recognized (SEASEE), (SEGSElR) and SElU. Staphylococcal foodborne diseases resulting from the consumption of food contaminated with SEs are one of the most common foodborne illnesses. Several methods for SEs detection have been developed; phenotypic detection like immunodiffusion, RPLA, ELISA, SPR, TRF, protein microarray. Genotypic detection as probes, PCR and oligonucleotide microarray. This study was extended over a period of 14 months, from October 2004 to end of December 2005 aiming to isolate and identify S. aureus from suspected cases of food poisoning, AD, PS and from nostrils of healthy persons with subsequent detection of SE by RPLA and genetically by PCR. In addition, comparing RPLA results with PCR results to detect the sensitivity, specificity and accuracy of each test. During this period 372 samples were taken; two hundred and forty eight stool samples from 198 cases and 50 healthy control, 89 skin swabs were taken from 35 AD patients, 30 Ps patient and 24 healthy control and finally 35 nasal swabs from 25 food handler and 10 medical personnel. Stool samples were cultured on mannitol salt agar and blood agar media while the other samples were cultured on blood agar medium. All S. aureus isolates were examined for SEs production by RPLA test, while only selected 25 isolates were examined for the existence of encoding genes by PCR; 14 were SEs positive by RPLA and the remaining 11 were negative. This study revealed the following results: Staphylococcal food poisoning is one of the main causes of food borneillness in Egypt (24.7%). It is common during summer months, which favor S. aureus growth and SEs production. While milk and milk products represents the main type of food involved in SFP and SEA is the commonest SEs detected among SFP isolates. Food handlers nasal colonization with enterotoxigenic S. aureus is a potential risk factor for development of SFP. There is a high prevalence of S. aureus skin colonization among AD and PS cases. Furthermore, the severity of AD or PS directly correlates to colonization with enterotoxigenic S. aureus. Reversed passive latex agglutination is a very good method for SEs detection with a good sensitivity and accuracy. However this method is not rapid (3 days) and depends on adequate gene expression. While Polymerase chain reaction is a very specific, sensitive, accurate and relatively rapid method for SEs detection.