مرکز منطقه ای اطلاع رساني علوم و فناوري - بررسي تيپهاي سرولوژيك سالمونلاهاي جداشده از نمونه هاي باليني و اثرات ضدميكروبي سفالوسپورينهاي نسل سوم

چكيده لاتين :

Background and Objectives: Infections resulting from Salmonella typhi and non-typhi Sairnonella are still of special significance in many parts of the world especially in developing countries. Different types ofsalmonella have increasingly become resistant to the common antibiotics used in therapy. Our main objective was to study in vitro effects of five third - generation cephalosporins on 413 Salmonella strains which had been isolated from different clinical samples in Tabriz Childrenʹs Medical Center. The results were compared with routine antibiotics (chloramphenicol,ampicillin, trimethoprim - sulfamethaxazole) prescribed in salmonella infections, so that effective measures could be taken for its treatment. Materials and Methods: Four hundred and thirteen sairnonella strains isolated from different clinical samples including feces, blood, cerebrospinal fluid (CSF), wound, sputum and urine were studied. The clinical samples were cultured on to selective and differential media including SS agar, EMB, KIA, , blood agar , nutrient agar, and into trypticase soy broth as well as enrichment medium (selenite broth). The strains were identified using biochemical tests and antisera (bioMerieux). Sensitivity test on the isolated strains was carried out using the disk-agar diffusion (Kirby - Bauer) method. Results: Out of 413 sairnonella strains two hundred and eighty eight strains (70%) were isolated from stool and 95(23%) strains from blood, while 10 (2.2%), 9 (2.1%), 8 (2%) and 3 (0.7%) strains were isolated from CSF, wound, urine and sputum samples respectively. The isolated organisms were identified using biochemical and serological tests and were arranged in the order of frequency of occurrence as: 292 (70%) serogroup B strains, 58 (14%) serogroup A strains, 39 (9.4%) serogroup C strains, and 24 (5.8%) Sairnonella typhi strains. Thus, 93.4% of the collecled salmonella strains were identified as non-typhi sairnonella and 5.8% as S. typhi. All of the sairnonella strains were sensitive to cefotaxime, ceftriaxone, ceftazidime, cephaperazone and the only resistance encountered belonged to non-typhi group in which 82 (21%) strains were resistant to cephaperazone. Non-typhi sairnonella strains were also found resistant to ampicillin (98.7%), chloramphenicol (87.2%) and trirnethoprim-sulfamethaxazole (58.6%), while S.typhi isolates revealed resistance of 4%, 1.3% and 4% against the mentioned antibiotics respectively. 53.2% of the studied non-typhi sairnonella strains showed resistance pattern of ampicillin + chloramphenicol + trimethoprim -sulfamethaxazole and 32.7% of them were resistant to ampicillin + chloramphenicol, while only 4.2% of the S.typhi strains showed resistance pattern of ampicillin + trimethoprim - sulfamethaxazole and other 4.2% strains were found resistant to ampicillin + chloramphenicol. Conclusion: The prevalent sairnonella strains isolated in this study belonged to serogroupB, serogroupA, serogroupC and Salmonella typhi with pronounced presence of non-typhi groups. All Salmonella typhi and non-typhi salmonella were sensitive to the third generation cephalosporins tested in this study and the only resistance encountered concerning the third generation cephalosporins was that of non-typhi salmonella against cephoperazone (21%), underlining their importance in therapy of salmonella infections. Single resistance and multiple resistance against routine antibiotics used in treatment of salmonella infections were encountered both in Salmonella typhi and non-typhi sairnonella.