The bacterial causes of nosocomial infections associated with short and long term-catheter

Abstract number: 1135_21

Sadeq R., Mowafy H., El-Hosiny M., Abdel-Motleb M.

The urinary tract infection is the most frequent site of nosocomial infections, accounting for approximately 40% of all NCIs. Catheterization is the most risk factor that predispose for such UTI. Two hundred sixty-six strains (76%) out of 348 catheterized patients were isolated. Out of these 266 strains, 212 cases were identified as NCIs, 54 cases (20%) were identified as community acquired infection. The isolated strains were found to be 202 (76%) Gram-negative bacilli, 32 (12%) S. aureus and 32 (12%) Candida isolates. The organisms were more common in NCIs than in community- acquired infections. Nosocomial infections were higher in the urology ward than in other ward involved in the study. The most effective antibiotic against S.aureus was vancomycin (100%). For Gram-negative bacilli, the most effective antibiotics were amikacin (for E. coli), tobramycin (for P. mirabilis), cefotaxime (for K. pneumoniae) and ceftazidime (for P. vulgaris and E. cloacae). High level of antimicrobial resistance was noticed among P. aeruginosa, the most active antibiotic was amikacin. ESBL production was nearly the same in both NCL and community acquired infection, and it was highly prevalent among isolates of P. mirabilis (26%), followed by E. coli (8%). Other isolates showed no ESBL activity. Rough comparison of susceptibility results of E- test (ceftazidime strip) with that of disc diffusion and agar dilution methods in detection of the susceptibility test of the organisms to the antibiotic used. As regard the plasmid profile, it seemed that there is no particular association between the plasmid content and ESBL activity of the isolated nosocomial strains of both E. coli and P. mirabilis to explain interspecies relationship. ——— NCI = nosocomial infection UTI = urinary tract infection ESBL = extended spectrum B-lactamase