Nosocomial infections with extended spectrum beta lactamase producing enterobacteriaceae in pediatric intensive care unit of Zagazig university hospitals

Enterobacteriaceae are of great concern because antimicrobial therapy of infections due to these resistant pathogens remains a clinical dilemma in hospitalized patients. It is also noted that there is an increase in the antibiotic resistance among Gram negative bacilli to third generation cephalosporins which is caused by expression of ESBL enzymes. Therefore, infections due to ESBL producing isolates continue to pose a challenge to infection management worldwide. The present study was conducted to highlight ESBL production among Eenterobacteriaceae isolated from nosocomial infections [NI] acquired in PICU of Zagazig University hospital by phenotypic and molecular method. The study was done on 604 PICU patients. Specimens for cultures were obtained according to site of NI: blood, urine, CSF, endotracheal tube [ET] aspirates and tips. isolates were confirmed by API 20E and subjected to double disc diffusion test for Phenotypic detection of the extended spectrum beta lactamases. The SHV genes were amplified by PCR, each on a 930 bp fragment. Resulting amplicons were subjected to restriction enzyme digestion for genotypic detection of SHV ESBL. From positive 96 specimens, 68 Enterobacteriaceae were isolated. The most numerous isolated enterobacteria were klebsiella spp [40.6 %], followed by E.coli [9.4%], Enterobacter Spp and Proteus spp [6.3% each], Serratia spp[5.2%], and Citrobacter spp [3.1%].66.2% of Enterobacteriaceae were ESBL producing isolates. Klebsiella pneumonia showed the highest percentage of ESBL producing strains [84.6%], followed by Citrobacter spp [66.7%], Serratia [60%], Enterobacter [50%], Porteus [33.3 %], and the least ESBL producer was E.coli [22.2%]. There is high significant difference between ESBL and Non ESBL producing organisms as regarding the presence of SHV ESBL type gene. 41 Out of 45 isolates [91.1%] of phenotypically ESBL producing Enterobacteriaceae carried the SHV ESBL type gene as indicated by presence of 2 bands of 768 and 162 by RFLP. This study concludes that extended spectrum beta lactamase [ESBL] producing Enterobacteriaciaeae should be put in mind while dealing with specimens of PICU. Double disc diffusion test is a simple and sensitive confirmatory test for ESBL detection. Also, PCR-RFLP is a rapid test for genotypic ESBL detection but needs molecular equipments and facilities

Virulence factors of Escherichia coli causing bacteriuria during pregnancy in comparison with isolates from community- acquired cystitis

Escherichia coli [E. coli] isolates from women with bacteriuria of pregnancy establish significant bacteriuria without causing symptoms of urinary tract infection [UTI]. In this study Escherichia coli isolates from patients with bacteriuria of pregnancy were compared phenotypically with uropathogenic E. coli [UPEC] from patients with community-acquired cystitis for the presence of established virulence determinants. The asymptomatic bacteriuria [ABU] strains from pregnant women were less likely to express type 1 fimbriae [26, 66%], P-fimbriae [20%] and ?-haemolysin [6.6%] than the other group [66.66% , 40% , and 13.3% respectively]. PCR analysis of the gene producing type 1 fimbria showed that the gene is present in 93.33% among both groups. However, determination of the phase switch orientation by analysis of positive PCR isolates showed that 3 of 14 ABU isolates of pregnant women [21.4%] was detectable in the on orientation compared to [64.2%] in community acquired cystitis patients. These data indicate that type 1 fimbriae are not necessary to maintain the majority of E. coli bacteriuria in pregnant women since there appears to be selection against their expression in this particular group in contrast to the considered role of this adhesion in community-acquired symptomatic infections

Fas- mediated peripheral T-cell apoptosis in chronic hepatitis-C virus infection

Hepatitis-C virus [HCV] infection is considered to be the leading cause of chronic liver disease with a prevalence rate between 0.5% and 10% in different countries. HCV is remarkably efficient in establishing persistent infection, possibly mediated by an impaired immune response to HCV infection. Regulation of T-cell apoptosis, which is mediated by interaction of a death receptors Fas [CD[95]] and its ligand [Fas ligand] is critical in generation of effective immune response against viral infection. Increase in peripheral T-cell apoptosis contributes to the down regulation of the immune system in chronic HCV infection

Aim of the work: Measuring the amount of apoptosis and the expression of Fas receptor in peripheral T-lymphocytes and their relationship to laboratory criteria in chronic HCV patients

Materials and methods: The study included two groups, 30 patients with chronic HCV infection [16 males, 14 females], aged 38 +/- 13.6 years and 10 healthy subjects as a control group [6 males, 4 females] aged 35.5 +/- 12.5 years. Both groups were subjected to peripheral blood mononuclear cell [PBMC] separation by Ficoll-Hipaque density gradient centrifugation, culture of peripheral blood T-lymphocytes in RBMI 1640 with 10% fetal calf serum for 48 hours in 37[degree]C with 5% CO[2]. Then, apoptosis of cultured T-lymphocytes was determined on flow cytometry using Annexin-V FITC [fluorescein isothiocyanate isomer-1] technique. The amount of Fas expression on separated Tlymphocytes was determined using FITC anti-Fas monoclonal antibodies. Liver function tests and viral load were taken from patient's reports

Results: Fas-expression in patients with chronic HCV was 32.19% +/- 12.42% which was significantly higher than that of healthy control group 6.4% +/- 2.65% [P < 0.001]. Amount of apoptosis of cultured T-lymphocytes from patient group [48.52% +/- 14.18%] was significantly higher than that of the control group [12.48% +/- 6.35%] [P < 0.001]. There was a significant positive correlation between Fas expression and the amount of apoptosis in the patient group [P < 0.001]. Also there were significant positive correlations between viral load and both of Fas expression and lymphocyte apoptosis [P < 0.01], while there was no significant correlation between liver enzymes levels and Fas expression or apoptosis in chronic HCV patients

Conclusion: There was increased Fas expression and apoptosis in peripheral T-lymphocytes in patients with chronic HCV infection which may contribute to down regulation of the immune response and persistent infection

Pulmonary tuberculosis among municipal street cleaning workers at Zagazig city; an epidemiological study

The risk for occupational exposure to pulmonary tuberculosis is increasing among municipal workers as they are the poorly paid and poorly educated workers, occupationally exposed to different biohazards, and usually work without adequate protective equipments. The aim of this study is determining the magnitude of pulmonary tuberculosis among municipal street cleaners, identifying some of the associated occupational risk factors, and identifying the DNA fingerprint patterns of mycobacterium tuberculosis isolates among those workers. Three hundred and twenty [320] male municipal street cleaners and 200 male drivers were included in the initial screening procedures of the tuberculosis survey; where they were subjected to a pre-constructed questionnaire, clinical examination, mass miniature radiography [MMR], and tuberculin skin testing. Chest X-ray and CT were done to confirm the diagnosis in subjects with any suspected lesions detected by MMR. Moreover, pulmonary TB suspects underwent sputum examination for acid fast bacilli, sputum culture, and biochemical tests to speciate mycobacterial isolates. Genotyping of Mycobacterium tuberculosis isolates, from the diagnosed cases with active pulmonary TB, was done using polymerase chain reaction amplifying the DNA fragments between insertion sequence IS6110. The study revealed that municipal street cleaners had significantly higher risk for Mycobacterium tuberculosis infection, as detected by tuberculin skin testing and chest radiography, than did the controls [OR=3.88, 95% CI; 2.4-6.19 and OR=3.02, 95 % CI; 1.07-9.22, respectively]. Moreover, higher percent of the street cleaners [3.4%] were classified as pulmonary tuberculosis suspects compared to the controls [1%]; however the difference between both groups of workers was not of statistical significance. Pulmonary tuberculosis disease was confirmed in 7 out of 320 street cleaners [2.2%]. Moreover, long duration of employment and bad street status were found to be associated with pulmonary TB disease in such workers. Finally, genotyping of Mycobacterium tuberculosis isolates from the 7definite cases of pulmonary TB, revealed 2 distinct sets of fingerprint patterns; this may suggest that these workers acquired TB from 2 different sources of infection. The study concluded that: Genotyping of M. tuberculosis isolates is mandatory in the study of TB epidemiology. Municipal street cleaners are at increased risk for occupational acquisition of Mycobacterium tuberculosis infection and contracting pulmonary TB disease

Interleukin-1 receptor antagonist among chronic renal failure pediatric patients with and without hemodialysis

During hemodialysis [HD], human blood leucocytes in circulation are exposed to several extraneous challenges, thus stimulated to secrete many inflammatory cytokines and its inhibitors as inter-leukin-1 and interieukin-1 receptor antagonist [IL-Ira]. The aim of this study was to investigate difference in the level of IL-IRa synthesis by peripheral blood mononuclear cells [PBMC] between CRF patients under conservative treatment and CRF patients under hemodialysis, and if this cytokine-specific inhibitory protein of PBMC can be used as a marker of dialysis related morbidity. The study included 44 subjects divided into 3 groups: [A] control group, [B] Chronic renal failure[CRF] under conservative treatment, [C] CRF under HD. Peripheral blood mononuclear cells [PBMC] were separated by ficoll-Hypaque. Spontaneous and Phytohemagglutinin [PHA] stimulated total IL-1Ra synthesis [cell-associated and secreted] by cultured PBMC was measured using EL-ISA method. The results of the study revealed that there were significant spontaneous total IL-IRa synthesis by PBMC in dialysis patients [group C] 2812 +/- 836 and in patients with conservative treatment [group B] 1791.2 +/- 252 compared to control group [group A] 940 +/- 227.8 [P value <0.001]. There were significant spontaneous total IL-IRa synthesis by PBMC in dialysis patients [group C] 2812 +/- 836 compared to patients with conservative treatment [group B] 1791.2 +/- 252 [P value <0.001]. There were significant PHA stimulated total IL-IRa synthesis by PBMC in dialysis patients [group C] 34041 +/- 8906 and in patients with conservative treatment [group B] 8565 +/- 1244 compared to control group [group A] 2980 +/- 608 [P value <0.001]. There were significant PHA stimulated total IL-IRa synthesis by PBMC in dialysis patients [group C] 34041 +/- 8906 compared to patients with conservative treatment [group B] 8565 +/- 1244 [P value <0.001]. There was positive correlation between PHA stimulated total synthesis of ILIRa and spontaneous total synthesis of ILIRa by PBMC in the 3 groups [P value <0.001]. There was significant correlation between IL-IRa [spontaneous and stimulated] with blood pressure, urea and creatinine level [P value <0.001]. This study concluded that PBMC of CRF patients synthesize significant level of IL-IRa compared to PBMC of healthy subjects. Also, PBMC of CRF patients on HD synthesize significant level of IL-IRa compared to PBMC of CRF under conservative treatment. Lastly, IL-IRa synthesis by PBMC of CRF patients was correlated with blood urea, serum creatinine and blood pressure level