Susceptibility of multidrug resistant pseudomonas aeruginosa to commonly used biocides and its association with Qac efflux pump genes

To assess the prevalence of qacE?1 and qacE genes and their correlation to antibiotic and biocides resistance in Pseudomonas aeruginosa isolated in Egypt. Susceptibility was assessed for 14 antibiotics in 136 Pseudomonas aeruginosa isolates using agar diffusion method. The minimum inhibitory concentration of 6 biocides, Savlon, Povidone-iodine, Phenol, Formalin and two Chlorine releasing agents were determined using macro-dilution method. Presence of qacE?1 and qacE genes was examined by polymerase chain reaction. There were 34.4 % of Pseudomonas aeruginosa isolates identified as multidrug resistant. Phenol and formalin displayed a higher antiseptic/disinfectant activity compared to other biocides tested. Savlon and Povidone-iodine displayed antibacterial activity when used in recommended dilutions. Minimum inhibitory concentration values of chlorine releasing agents were higher than the dilution prescribed by their manufactures. The qacE gene was only detected among multidrug resistant Pseudomonas aeruginosa. The qacE?1 gene was identified in 57.8% of multidrug resistant isolates and 21.4% in susceptible strains. The prevalence of qac genes among clinical Pseudomonas aeruginosa were 42.3%. Current study concluded thatthere was a correlation between multidrug resistance Pseudomonas aeruginosaandqacE?1 gene, whereas there was no correlation between increased MIC values of biocides and the presence of Qac genes

Detection of central venous catheter-related bacteremia by gram stain-acridine orange leukocyte cytospin test

Central venous catheter-related bloodstream infection [CR-BSI] remains a main source for septic morbidity and occurs in 4-14% of all catheters. Besides, its diagnosis lacks accuracy. We aimed to determine the diagnostic performance of the Gram stain Acridine Orange Leukocyte Cytospin [AOLC] test for the diagnosis of CR-BSI in ICU patients as compared to the routine semi-quantitative catheter culture method performed in our laboratory. A total of 50 intensive care unit patients with CVC having clinical suspicion of CR-BSI were enrolled in this study. The first two milliliters blood, were aspirated from the catheter before being removed and the Gram stain-AOLC test was done. About the same time, five to eight milliliters blood were collected from a peripheral vein, under aseptic conditions, inoculated onto a blood culture medium and sent to the microbiology laboratory for blood culture. Catheters were removed aseptically the tip was cut and sent to the microbiology laboratory for culture by a semi-quantitative technique. Catheter culture [CC] was positive in 46/50 [92%] of patients. Yet, only 23/46 patients [50%] met the criteria for diagnosis of CR-BSI. The sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV] and diagnostic accuracy [DA] for catheter culture were 100%, 15%, 50%, 100% and 54%, respectively. The AOLC test was positive in 32/50 patients [64%]. Twenty two out of the 32 [68.75%] positive cases had microbiologically confirmed CR-BSI. The AOLC test had 96% sensitivity, 63% specificity, 69% PPV, 94%NPV and 78% DA. The addition of the Gram-stain to the AOLC test was found to be positive in 18/50 patients [36%]. In patients with microbiologically confirmed CR-BSI, the Gram Stain-AOLC test was positive in 14/23 patients [60.8%]. The Gram-stain AOLC test had 61% sensitivity, 85% specificity, 78% PPV, 72% NPV and 74% DA. While, catheter culture by the semi-quantitative technique is more sensitive than the Gram-stain AOLC test in diagnosing CR-BSI, the Gram-stain AOLC test was found to be simple, rapid and specific and does not required the catheter removal. Thus can be used as a first line investigation for the diagnosis of CR-BSI, on which the decision to remove or replace a suspected CVC can be safely and accurately made

Role of doppler echocardiography in diagnosis of mitral valve diseases

Doppler echocardiography has been established as an indispensable, noninvasive technique in the evaluation of mitral valve diseases. This study included 2 groups, a group of 30 patients having mitral valve lesions and a control group of 10 normal subjects. A meticulous Doppler echocardiographic examination was performed for each subject. The normal diastolic mitral valve flow pattern was demonstrated and the mean values of the maximum velocity of blood flow [Max. V], the maximum transvalvular pressure gradient [Max. PG], and the maximum pressure half time [Pt 1/2] were recorded. Patients of the first group were diagnosed and classified according to the type of lesion, whether isolated mitral stenosis [10 cases], isolated regurgitation [18 cases] or combined stenosis and regurgitation [2 cases]. Max. V, Max. PG and Max. Pt 1/2 were calculated in each case and the characteristic Doppler flow pattern across the valve was demonstrated in each lesion. Doppler echocardiography showed high sensitivity and specificity in the diagnosis of mitral valve diseases and in assessment of its severity