Introduction: Pseudomonas aeruginosa (P. aeruginosa) is a highly resistant opportunistic pathogen and is capable of forming biofilms on medical devices. Bacterial biofilms, which are micro-colonies encased in extracellular polysaccharide material are so difficult to be treated by conventional antibiotics. During the last decade, P. aeruginosa phages have been extensively examined as an alternative to antimicrobial agents. The aim of the study was to assess bacteriophageantibiotic combination on planktonic and biofilm states of P. aeruginosa isolates. Materials: In this study, we isolated 6 lytic phages, from hospital effluents, they were tested against 50 P. aeruginosa strains, isolated from different clinical specimens delivered to the Diagnostic Microbiology Laboratories, Faculty of Medicine, Alexandria University. Results: Out of the 50 isolates, 15 were susceptible to these phages. So the biofilm forming capacity of these 15 isolates was investigated. The results showed that 14 isolates (93.33%) produced detectable biofilm. The minimum inhibitory concentration (MIC) and minimum biofilm eradication concentration (MBEC) assays were used to evaluate the antibiotic sensitivity patterns of these P. aeruginosa isolates in their planktonic and biofilm phases to amikacin and meropenem. Also, the effects of phage on the planktonic and biofilm states of isolates at different multiplicities of infections (MOI) were tested. On the planktonic state, the amikacin-phage combination showed synergistic effect (P = 0.001), and the meropenem-phage combination showed synergistic effect (P = 0.003). On the biofilm state, the amikacin-phage combination showed biofilm eradication Please cite this article in press as: Nouraldin AAM et al. Bacteriophage-antibiotic synergism to control planktonic and biofilm producing clinical isolates of Pseudomonas aeruginosa, Alex J Med (2015), http://dx.doi.org/10.1016/j.ajme.2015.05.002in 50% of the isolates (P = 0.003). On the other hand, the meropenem-phage combination showed biofilm eradication in 14.3% of the strains. Conclusion: The combination of phage and antibiotics could have potentially more benefits on P. aeruginosa planktonic and biofilm states than just using phages or antibiotics alone.

Brucellosis is a widespread zoonosis. Currently the diagnosis of this zoonosis is based on microbiological and serological laboratory tests. Polymerase chain reaction (PCR) has been used to detect DNA from Brucella. Different target genes, primer pairs, PCR techniques, and extraction procedures have previously been published for Brucella detection. But only a few of these primers have been used in human samples, and only one study has been carried out to compare sensitivity between them. In the present study, 3 sets of primers and 3 different PCR protocols amplifying 3 different regions of the Brucella genome were compared for detection of Brucella DNA in a peripheral-blood PCR assay to conclude which is most suitable for the clinical diagnostic laboratory. These 3 pairs of primers amplify 3 different fragments included in (i) a gene encoding a 31 kDa Brucella abortus antigen (B4/B5), (ii) a sequence 16S rRNA of B. abortus (F4/R2), and (iii) a gene encoding an outer membrane protein (omp-2) (JPF/JPR). Some modifications on the reported techniques were applied during the present work to improve the outcome. The results showed that the B4/B5 primer pair had the highest sensitivity for detection of positive samples (98%), the JPF/JPR primer pair detected 88.4% of positive samples, whereas F4/R2 primer pair was the least sensitive, being able to detect only 53.1% of positive samples. The specificity of the 3 techniques was 100%. The B4/B5 primer pair was also able to detect the smallest number of bacteria (700 cfu/mL), whereas JPF/JPR was able to detect 7 x 105 cfu/mL and F4/R2 was able to detect 7 x 107 cfu/mL. It is thus concluded that using the B4/B5 primer PCR with the suggested modifications is a robust assay, which meets the sensitivity requirements to be used for testing of human blood samples for brucellosis in the diagnostic laboratory.

In the present study, several conventional methods to detect methicillin-resistant Staphylococcus aureus (MRSA) were compared with polymerase chain reaction (PCR) detection of mecA gene-positive isolates. Cefoxitin E-test was also evaluated as a possible phenotypic method of MRSA detection. Oxacillin agar screen and PBP2' latex agglutination methods were found to be more sensitive than oxacillin and cefoxitin disk-diffusion methods. Cefoxitin disk diffusion was found to be the most specific. A combination of oxacillin agar screening with cefoxitin disk diffusion, or oxacillin disk diffusion with PBP2', improved sensitivity and specificity. Cefoxitin E-test with the current break points had low sensitivity and specificity (33.3% and 75%, respectively) for the detection of MRSA. However, changing the break points to or= 6 microg/ml for sensitive and resistant, respectively, greatly improved both. Changing the 30-microg cefoxitin disk-diffusion break points to

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