الفهرس | Only 14 pages are availabe for public view |
Abstract In recent years, the prevalence of carbapenem-resistant P. aeruginosa isolates has become a worldwide concern. The aim of the present study was to study the antibiotic resistance pattern of P. aeruginosa isolated from patients with thermal injury at Beni-Suef University Hospital and to study the prevalence of MBL production in these isolates by phenotypic detection and the detection of blaIMP-1, bla NDM and blaVIM genes as genetic markers for carbapenem resistant isolates. This cross sectional study included 103 patients with thermal injury. They were recruited and assessed for eligibility from the plastic surgery unit at Beni-Suef University Hospital. 103 samples were collected from the burn injuries under aseptic precautions using sterile cotton swabs and were transported immediately to the microbiology laboratory for culture and examinations. Regarding the demographic characteristics of the studied cases, the largest percentage of the studied patients were≥31 years old (40.8%) followed by patients ≤10 years old (33.0%). Moreover, more than one-half of them were males (58.3%) and resided in rural areas (63.1%). Regarding distribution of the isolated organisms from studied samples, P. aeruginosa was isolated from 31.1% followed by Staph. aureus (25.2%), Klebsiella (17.5) then Acinetobacter (15.5%). The present study demonstrated that the incidence of P. aeruginosa infection was higher among patients ≤ 10 years old (38.2%), males (36.7%), and residents of urban communities. Regarding the duration of hospital stay, there was significant difference in P.aeruginosa isolated from patients with short duration of hospital stay (12.1± 4.8) compared with those where other organisms were isolated (20.3±8.2) (p-value=0.001). Regarding the resistance of the studied P. aeruginosa to different antibiotics disks, the present results demonstrated that a high percentage of P. aeruginosa was resistant to eight out of the nine used antibiotics sensitivity disks: meropenem (75.0%), imipenem (87.5%), amikacin (62.5%), gentamicin (78.12%), piperacillin (53.13%), cefepime (90.6), ceftazidime (71.8%), and ciprofloxacin (68.7%), while the least percentage of the studied P. aeruginosa was resistant to aztreonam (18.8%). The present study demonstrated that high percent of P. aeruginosa showed pan drug resistance to antibiotics (62.5%). Moreover, 96.9% of the studied P. aeruginosa were resistant to one or both categories of carbapenem antibiotics. 68.8% were resistant to both meropenem and imipenem, 21.9% were resistant to imipenem alone, and 6.3% were resistant to meropenem alone. By using CDDT, more than one-half of the examined specimens were positive MBL producers (53.1%). Furthermore, around two-thirds of the examined specimens by DDST were positive MBL producers (65.6%). PCR examination of the carbapenem-resistant isolates showed that the prevalence of blaIMP, VIM, and NDM genes were (0%), (96.8%), and (96.8%) respectively. The present study demonstrated that there was a statistically significant increase in cefepime resistance among carbapenem-resistant P. aeroginosa in comparison with carbapenem-sensitive P. aeroginosa (P-value=0.002). Additionally, the prevalence of carbapenem-resistant isolates was significantly higher among isolates that showed resistance to the following antibiotics: amikacin, gentamicin, piperacillin, cefepime, ceftazidime, and ciprofloxacin at P-value equals (0.027, 0.001, 0.001, 0.032, 0.002, and 0.001), respectively. The present results demonstrated that the sensitivity, specificity, positive predictive value, and negative predictive value of DDST for detecting MBL were 56.7%, 100%, 100%, and 7.1% respectively. The kappa value denoting the measure of agreement is poor (0.038). While the sensitivity, specificity, positive predictive value, and negative predictive value of CDST for detecting MBL were 66.7%, 0.0%, 95.2%, and 0.0% respectively. The kappa value denoting the measure of agreement is poor (-0.03). |