Isolation and antibiotic susceptibility of Salmonella, Shigella, and Campylobacter from acute enteric infections in Egypt

While Campylobacter, Salmonella, and Shigella remain major contributors to acute enteric infections, few studies on these pathogens have been conducte d in Egypt. From January 1986 to December 1993, 869 Salmonella, Shigella an d Campylobacter strains were isolated from stool specimens from 6,278 patie nts, presenting to the Abbassia Fever Hospital, Cairo, Egypt, with acute en teric infections. Salmonella predominated, totalling 465 isolates, followed by Shigella with 258 isolates, and Campylobacter with 146 isolates. Of the Shigella isolates, 124 were Shigella flexneri, 49 were S. sonnei, 47 were S. dysenteriae (mainly serotype 1, 2, and 3), and 38 were S. boydii. Campyl obacter spp. comprised 92 Campylobacter jejuni and 54 C. coli isolates. Iso lation of Salmonella was highest during the months of February-March, June- July, and October-November, while that of Shigella was maximal from July to October. Isolation of Campylobacter increased during May-June and again du ring August-October. Although Salmonella was sensitive to amikacin, aztreon am, ceftriaxone, and nalidixic acid, it was, however, resistant to erythrom ycin, streptomycin, ampicillin, chloramphenicol, and tetracycline. Shigella (>80%) was sensitive to amikacin, ceftriaxone, cephalothin, sulphamethoxaz ole-trimethoprim (except S. sonnei), aztreonam, and nalidixic acid. Resista nce (>50%) was noted only for ampicillin, chloramphenicol, and tetracycline . C. jejuni and C. coli were resistant to cephalothin, aztreonam, and strep tomycin. Some of the above antibiotics were employed to characterize the Eg yptian isolates, but did not have any clinical utility in the treatment of diarrhoea. Significant differences (p<0.05) were observed in the resistance profiles of Shigella and Salmonella between late 1980s and early 1990s. Th e results suggest the use of fluoroquinolones or a third-generation cephalo sporin as an empirical treatment of enteric diseases. However, alternative control strategies, including the aggressive development of broadly protect ive vaccines, may be more effective approaches to curbing morbidity and mor tality due to acute enteric infections.