ABSTRACT
Aims: To determine the prevalence of acquired pAmpCs in clinically important and relevant enterobacterial species and to characterize the molecular types of pAmpC present in our geographic area. Methodology: Sixty Enterobacterial clinical isolates resistant to third generation cephalosporins and to cephamycins were included in the study. Samples were collected for a period of 6 months between July 2008 and December 2008 from Theodor Bilharz Research Institute (TBRI), Egypt. Bacterial species were identified using API E20. AmpC genes clusters: (bla ACC, bla EBC, bla FOX, bla CMY, bla MOX, and bla DHA) were tested by PCR and DNA sequencing. Clonal relatedness of AmpC-producing Klebsiellae isolates was determined by Pulsed Field Gel Electrophoresis (PFGE). Results: AmpC genes were detected in 28.3% (17/60) of the study population including E. coli, Klebsiella and Proteus mirabilis (P mirabilis). CMY-2 enzyme was found disseminating in all 6 AmpC-positive Escherichia coli (E. coli) and in 6/10 of Klebsiellae species. Only one Klebsiella pneumonia (K. pneumonia) isolate harbored CMY-4 while DHA-1 was detected in 3 Klebsiellae and in one P. mirabilis isolate. PFGE patterns showed no clonal relatedness among the 6 CMY-2-positive Klebsiella isolates. Conclusion: Plasmid-mediated AmpC enzymes are important mechanisms of resistance to ß- lactam drugs. CMY-2 and DHA-1 are the most common gene clusters of pAmpC in our region. AmpC-type resistance in our hospital setting is not due to the dissemination of clonal strains but due to the spread of resistant genes. This is the first report from Egypt identifying DHA-1 and CMY-4 in enterobacterial isolates.
ABSTRACT
Introduction: Acute diarrhea continues to be a major cause of morbidity and mortality in children from developing countries. Determination of the frequency of diarrhea in an area; along with the proportion of disease caused by specific enteric agents of different origins; is considered the first step in controlling diarrheal diseases. Methodology: From 2005 to 2007; a hospital-based surveillance was conducted in two locations in Egypt to determine the causes of acute diarrhea in children younger than 5-years seeking treatment. Five additional enteric viral and parasitic pathogens were tested using commercially-available enzyme immunoassays (EIA) to re-evaluate the prevalence of diarrheal pathogens in undiagnosed cases.Results: Adenovirus; astrovirus; norovirus and G. lamblia were detected as the sole pathogen in 2 (n=34); 3 (n=56); 9 (n=191) and 7 (n=146) of the cases; respectively. E. histolytica was never detected as the sole pathogen. The percentage of diarrheal cases with a known cause increased significantly; from 48 (n=1;006) to 74 (n=1;568) (P0.0001). Conclusion: In our study; the incorporation of immunoassays yielded useful data in identifying pathogens in previously pathogen-negative diarrhea cases