Metallo-Beta-Lactamase Producing Pseudomonas aeruginosa in a Healthcare Setting in Alexandria, Egypt.

Pseudomonas aeruginosa has emerged as a major healthcare associated pathogen that creates a serious public health disaster in both developing and developed countries. In this work we aimed at studying the occurrence of metallo-beta-lactamase (MBL) producing P. aeruginosa in a healthcare setting in Alexandria, Egypt. This cross sectional study included 1583 clinical samples that were collected from patients admitted to Alexandria University Students' Hospital. P. aeruginosa isolates were identified using standard microbiological methods and were tested for their antimicrobial susceptibility patterns using single disc diffusion method according to the Clinical and Laboratory Standards Institute recommendations. Thirty P. aeruginosa isolates were randomly selected and tested for their MBL production by both phenotypic and genotypic methods. Diagnostic Epsilometer test was done to detect metallo-beta-lactamase enzyme producers and polymerase chain reaction test was done to detect imipenemase (IMP), Verona integron-encoded (VIM) and Sao Paulo metallo-beta-lactamase (IMP) encoding genes. Of the 1583 clinical samples, 175 (11.3%) P. aeruginosa isolates were identified. All the 30 (100%) selected P. aeruginosa isolates that were tested for MBL production by Epsilometer test were found to be positive; where 19 (63.3%) revealed blaSPM gene and 11 (36.7%) had blaIMP gene. blaVIM gene was not detected in any of the tested isolates. Isolates of MBL producing P. aeruginosa were highly susceptible to polymyxin B 26 (86.7%) and highly resistant to amikacin 26 (86.7%). MBL producers were detected phenotypically by Epsilometer test in both carbapenem susceptible and resistant P. aeruginosa isolates. blaSPM was the most commonly detected MBL gene in P. aeruginosa isolates.

Role of polymerase chain reaction as an early diagnostic tool for neonatal bacterial sepsis.

BACKGROUND: Neonatal bacterial sepsis is a challenging disease that needs to be detected early. As it is a life-threatening condition, the use of an approach that could be more rapid than standard culture and identification techniques for detection of neonatal sepsis would be highly desirable. OBJECTIVE: The aim of this work was to assess the effectiveness of the PCR technique compared with blood culture for the early detection of bacterial sepsis. PARTICIPANTS AND METHODS: This study included 50 neonates with suspected sepsis. A blood sample was collected and divided into two parts: one part was subjected to broad-range 16S rDNA detection by PCR (runtime 6 h) and the other part was inoculated onto blood culture bottles (monitored for 6 days). In addition, some risk factors associated with clinical sepsis were explored. RESULTS: Twenty-four neonates (48%) were positive for bacterial DNA by PCR and 17 cases (34%) had a positive blood culture. Seventeen neonates were positive for both blood culture and bacterial DNA. There was no statistical significance between both methods and the risk factors studied, except for sex and blood culture. The results of PCR in the detection of bacterial sepsis when compared with blood culture showed 100% sensitivity, 78.79% specificity, 70.83% positive predictive value, and 100% negative predictive value. An excellent agreement was found between the two methods (κ=0.716, P<0.001). CONCLUSION AND RECOMMENDATIONS: The PCR detected a higher rate of sepsis in neonates than blood culture. Therefore, PCR is useful for the rapid and accurate diagnosis of bacterial infection, with a significant impact on the current inappropriate and unnecessary use of antibiotics in the treatment of newborns. We recommend using broad-range PCR to rapidly diagnose infants with sepsis.