Rasha Elsherif

High rates of intestinal colonization with extended-spectrum lactamase-producing Enterobacteriaceae among healthy individuals.

Background Infections caused by extended-spectrum β-lactamase (ESBL)–producing bacteria become an emerging problem in the community setting in many parts of the world. Objective The objective of the study was to determine fecal carriage of ESBL-producing organisms in a community setting. Methods A total of 632 fecal specimens from healthy individuals were screened for ESBL using the agar screening test with MacConkey agar plates supplemented with 1 μg/mL of cefotaxime for selection of ESBL-producing strains and confirmed by the Clinical Laboratory Standards Institute combined disk method. Results Four hundred isolates (63.3%) were ESBL producers. Two hundred eighty-five isolates (71.25%) of them were Escherichia coli and 96 (24.0%) Klebsiella pneumoniae. Conclusion We concluded that the community could be a reservoir of these ESBL-producing bacteria and enzymes.

Polymerase Chain Reaction-guided Diagnosis of Infective Keratitis – A Hospital based Study

Purpose: To compare polymerase chain reaction (PCR) to microbial culture and smear for detection and identification of bacterial and fungal pathogens in suspected microbial keratitis. Materials and methods: Corneal scrapings from 88 patients with suspected infectious keratitis were subjected to routine bacterial culture and sensitivity, Gram’s stain, fungal culture; potassium hydroxide (KOH) wet mount, and PCR. PCR was performed with primer pairs targeted to the 16S and 18S r RNA gene. The result of the PCR was compared with conventional culture and Gram staining method. Results: By broad-range PCR, 40 (45.45%) cases were positive for fungi (90.9% sensitivity), 26 (29.5%) were culture positive (59.09% sensitivity), 29 (33%) of all patients were positive for bacteria by broad-range PCR (87.9% sensitivity) and 19 (21.6%) were culture positive (57.58% sensitivity). The time taken for PCR assay was 4–8 h whereas positive fungal cultures took 2–10 days and bacterial culture from 2 to 4 days. Smears were positive for fungi in 29 eyes (33% of cases, 65.91% sensitivity) and for bacteria in 11 eyes (12.5% of cases, 33.33% sensitivity). Conclusions: DNA amplification with universal primers is a promising diagnostic tool in cases of infectious keratitis where routine laboratory culture failed to identify the pathogen. PCR may be performed in cases where the results of corneal scraping stains are negative without waiting for the results of the culture.

Mutations affecting domain V of the 23S rRNA gene in Helicobacter pylori from Cairo, Egypt

Background: Clarithromycin is a main component of the recommended first-line triple therapy for Helicobacter pylori in Egypt. We aimed in our study to investigate the prevalence of clarithromycin-resistant H. pylori strains due to the point mutations at domain V of the H. pylori 23S rRNA among the Egyptian population using the polymerase chain reaction/restricted fragment length polymorphism (PCR/RFLP) assay. Methods: Gastric biopsies obtained from 100 dyspeptic patients who consecutively attended at Cairo University Hospital during the period from January to November 2013 were subjected to PCR/RFLP in order to detect the point mutations at domain V of the H. pylori 23S rRNA associated with clarithromycin resistance. The PCR amplicon of the 23S H. pylori rRNA is restricted with MboII for detection of A2142G mutation and with BsaI for A2143G mutation. Results: The prevalence of H. pylori infection among 100 patients was 70%; clarithromycin resistance was detected in 39/70 (57.7%) of positive H. pylori isolates. Occurrence of 23S rRNA A2142G mutations resulted in two DNA fragments (418 and 350 bp) by PCR-RFLP; on the other hand, no A2143G mutations were detected. Conclusions: The high prevalence of clarithromycin resistance (57.7%) caused by A2142G mutations at domain V of the H. pylori 23S rRNA may mandate changing of the standard clarithromycin-containing triple therapy. The PCR/RFLP assay was a rapid and accurate method for molecular detection of H. pylori infection in addition to determination of different nucleotide mutations causing clarithromycin resistance.

Nail dermoscopy is a helpful tool in the diagnosis of onychomycosis: A case control study

The diagnosis of onychomycosis is moving from clinico-pathologic tools, which are time-consuming and give false negative results in up to 35% of cases [1], into clinico-imaging diagnosis [2]. Distinctive dermoscopic features for onychomycosis have been reported [3-5]. Our aim was to confirm these distinctive features and to correlate their association with invasive diagnostic tools for onychomycosis.After approval of the Dermatology Research Ethical Committee of the Faculty of Medicine, Cairo University, [...]

Integron-mediated multidrug resistance in extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolated from fecal specimens in Egypt.

BACKGROUND The increasing incidence of hospital-acquired infections due to extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae represent a major health problem because of few therapeutic alternatives. The fecal flora can represent a reservoir for ESBL genes. Integrons are genetic structures capable of capturing gene cassettes that usually encode antibiotic-resistance determinants. OBJECTIVES To investigate the antimicrobial susceptibility of fecal isolates of ESBL-producing Escherichia coli and Klebsiella pneumoniae from hospitalized and nonhospitalized Egyptian patients and to determine the prevalence of class 1 and class 2 integrons together with the most common ESBL-producing genes (bla TEM, SHV, CTX-M, and OXA) among the collected isolates. MATERIALS AND METHODS Ninety-six fecal samples were collected: 48 samples from hospitalized patients admitted at Kasr Al-Ainy University Hospital, Cairo and 48 from outpatient clinics. Samples were inoculated on MacConkey agar and identified. All isolates were tested for their susceptibility to different antimicrobial agents using a standard disk diffusion method. The double-disk synergy test was applied for screening ESBL. All ESBL-producing isolates were confirmed by molecular testing to detect ESBL-encoding genes (SHV, TEM, CTX-M, and OXA). To identify the strains carrying integrons 1 and 2, the conserved regions of integron-encoded integrase gene intI1 and intI2 were amplified. RESULTS E. coli isolates accounted for 52.1% of the isolates collected from hospitalized patients and 60.4% of those collected from outpatient clinics. Results of the double-disk synergy test were positive in all E. coli and K. pneumoniae isolates, indicating the presence of ESBL production. Isolates of both groups showed variably high degrees of resistance to ciprofloxacin and co-trimoxazole. The most predominant ESBL gene in both groups was the bla CTX-M gene (93.8%) and the least prevalent was the bla OXA gene, which was not detected in any of the study isolates. Between the other two genes, the bla TEM gene was more common than the bla SHV gene in the two study groups. Class 1 integron was more prevalent among hospitalized patients, being detected in 64.6% of isolates from this group. Class 1 integron was linked with the bla CTX-M gene (P=0.039). Class 2 integron was more prevalent in the nonhospitalized group (85.4%) compared with the hospitalized group (50%) (P<0.001). CONCLUSION AND RECOMMENDATIONS ESBL-producing E. coli and K. pneumoniae showed a marked degree of antibiotic resistance in both hospitalized and nonhospitalized study groups. The high prevalence of class 1 and 2 integrons among isolates of both groups has a serious impact on the spread of antibiotic resistance.

Emergence of Gram-Negative Bacilli with Concomitant bla NDM-1 - and bla OXA-48 -Like Genes in Egypt

Multidrug-resistant Gram-negative organisms have emerged as a major threat to hospitalized patients, and are associated with serious morbidity and mortality. This study aimed to characterize carbapenem resistance genes among Gram-negative bacilli isolated from clinical samples from patients in the intensive care unit of Cairo University Hospital. A total of 211 samples were collected from patients showing clinical evidence of infection. Bacteria were isolated and identified by conventional microbiological methods. Acinetobacter baumannii isolates were furtherly characterized by polymerase chain reaction (PCR), using primers specific for blaOXA-51-like genes. The Kirby Bauer disc diffusion method was used to determine susceptibility patterns of isolates, and carbapenem resistance was further examined by a modified Hodge test. Positive isolates were tested for the presence of blaKPC, blaOXA-48, and blaNDM-like genes by PCR. NDM gene types were determined by direct sequencing. From the 211 samples, 229 Gram-negative bacilli were isolated. Fifty isolates (21.2%) were resistant to carbapenem. PCR analysis showed that none of the 50 isolates carried blaKPC-like genes, while 24 (48%) isolates carried blaOXA-48-like genes, 8 (16%) carried blaNDM-1, and five isolates (10%) carried both blaNDM-1 and blaOXA-48-like genes. These results indicate that continuous surveillance of these multidrug-resistant pathogens is urgently required. And that is very important is to activate the antimicrobial stewardship programs of which the most important is restriction of the big gun antibiotics like carbapenems, colistin, tigecyclin and vancomycin and restricting their prescription to privileged specialties.