Do antibiotic-coated central venous catheters reduce catheter-related bloodstream infection in intensive care patients?

Central venous catheters [CVCs] are a major cause of nosocomial bloodstream infections, which are difficult to control Catheters bonded with either antiseptics or antibiotics that constantly and slowly release antimicrobial substances are assumed to be beneficial in reducing rates of colonization and catheter-related infections. This prospective, randomized clinical trial was designed to evaluate the efficacy of catheters coated with either chlorhexidine and silver sulfadiazine [CHSS], or minocycline and rifampin [M/R] in reducing catheter-related colonization and bloodstream infections [CR-BSIs] in intensive care patients. 90 adult inpatients with CVCs, for 3 days or more, were conducted in this clinical trial [classified into three equal groups]. According to the type of the catheter, the patients were assigned to undergo insertion of triple lumen polyurethane CVCs either in standard version [unimpregnated] [Group I], or impregnated with either CHSS [on the extraluminal surface only] [Group II], or M/R [on the extraluminal and intraluminal surfaces] [Group III]. Microbiological evaluation was done for the insertion site before catheterization and at removal of the catheter, CVCs [tips and subcutaneous parts] and peripheral blood after removal of the catheter if accompanied by clinical signs of infection. 114 patients were assigned to undergo CVC insertion but dropouts with missing evaluation totalled 24 cases leaving 90 catheters with complete data and final microbiological evaluation. Clinical characteristics as well as clinical diagnoses of patients enrolled were similar in all study groups. Regarding colonization of the insertion site before catheterization, there were no significant differences between the three groups. Impregnated catheters showed a highly significant reduction in colonization of insertion site at removal of the catheter when compared to unimpregnated ones [P <0.001]. Impregnated catheters [groups II and III] were dramatically less likely to be colonized as unimpregnated version [group I] [4/30 [13.3%]; 2/30 [6.6%] vs. 10/30 [33.3%]]; respectively [P < 0.001]. Only one case of CR-BSIs [3.3%] was detected among catheters impregnated with CHSS vs. 4 cases [13.3%] among the unimpregnated ones. No cases of CR-BSIs [0%] were detected in the group of M/R-impregnated catheters. The use of CVCs coated with either M/R or CHSS is associated with a reduction in the rate of catheter colonization and catheter-related bloodstream infection compared to standard [uncoated] catheters in intensive care patients. In addition, the anti-infective efficacy of catheters impregnated with M/R was higher than that of catheters impregnated with CHSS

Correction of Aberrant pre mRNA splicing using antisense oligonucleotides in B thalassemia patients with known IVS-I,nt 110 mutation

1VS In l 110 mutation is the most common mutation in Egyptian thalassemics. The mutation causes aberrant splicing ofpre-mRNA resulting in labile RNA causing deficient B-globin chain synthesis. Antisense oligonucleotide strategy is one of the more simple technique in gene therapy. Using oligonucleotides covering the aberrant splice site gives chance for normal splicing and correction of the anomaly at the RNA level. Blocking of aberrant splicing at IVS 1nt 110 site of B-globin pre-mRNA using antisense oligonucleotides results in subsequent restoration of normal mRNA production in B-thalasseamia patients with IVS 1nt 110 mutation This study involved 10 patients with known IVS IntllO mutation; 6 homozygous and 4 heterozygous patients peripheral blood mononuclear cells were separated and duplicate liquid culture systems were set using erythropoietin and stem cell factor with and without antisense oligonucleotides [20 micro. mol/ml]. Correction of aberrant splicing was evaluated by estimation of total hemoglobin, hemoglobin F, and a reverse transcriptase polymerase chain reaction followed by agar gel electrophoresis was used to amplify and detect both aberrant mRNA and normal mRNA in duplicate samples. Five cases [50%] showed correction after antisense oligonucleotide treatment, two cases showed the appearance of normal mRNA band with absence of aberrant band and in 3 cases an increased ratio of normal mRNA band to aberrant band was found [from 2:1 to 3:1 in two cases and from 2:1 to 4:1 in the third case]. The 5 corrected cases showed significant increase in total Hb which varied between 4 to 6 folds increase. Antisense oligonucleotide treatment corrects splicing ofpre-mRNA leading to appropriate expression of B-globin mRNA which may pave the way for treatment of thalassaemia.

Rapid flow cytometric test for the diagnosis of hereditary spherocytosis and its relevance to clinical severity

The causes of non-immunehereditary hemolyticanaemia include enzymopathy, hemoglobinopathy, abnormal cation transport and membranopathy. Hereditary spherocytoris [HS] is the most common membranopathy. In this study a new flow cytometic test measures the fluorescence in tensity of intact red cells labeled with eosin -5- maliernide. The dye reacts covalentily with lys-430 on the first extracellular loop of band 3 protein. In this study, red cells from patients with HS produced a greater degree of reduction of mean channel fluorescence [MCF] readings than those for other patients groups with other causes of anaemia and normal controls. The MCF for spherocytic patients was 20.4 +/- 5.2 as compared to the control group whose MCF was 35.9 +/- 2.6. The MCF readings of other patients groups included in the study were for thalassaemia patient [39.8 +/- 2.2], glucose -6- phosphate dehydrogenase deficiency patients [34.8 +/- 1.9] iron deficiency anaemia patient [30.25 +/- 1.2], autoimmune hemolytic anaemia patients [32.5 +/- 1.7] and chronic renal failure patients [34.6 +/- 1.7]. All these groups of patients gave MCF readings that were higher than those of HS. Thus the dye method proved to be a reliable and speedy diagnostic test [2 hours from sample collection to result] for the diagnosis of hereditary spherocytosis in routine hematology