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Background
Central line-associated bloodstream infections (CLABSIs) are among the most serious complications especially in blood cancer patients. In January 2013, Centers for Disease and Prevention (CDC) introduced a new surveillance definition of mucosal barrier injury-associated laboratory-confirmed bloodstream infection (MBI-LCBI). This study was to determine the impact of MBI-LCBI on CLABSIs and compare the clinical characteristics of MBI versus non-MBI-LCBI cases.Patients and methods
We retrospectively reviewed the records of 250 consecutive patients. They were admitted in department of hematology at Aichi Medical University Hospital. We applied the revised 2013 CLABSI surveillance protocol to all CLABSI cases identified during the 47-months period from May 2012 through June 2016.Results
A total of 44 CLABSIs were identified. The median patient age was 65 years (range, 12 to 89). Among 44 patients, 31 patients were diagnosed as leukemia (70.5%) and 12 patients as lymphoma (27.3%). Six patients underwent bone transplantation for leukemia or myelodysplastic syndrome (13.6%). A total of 20 patients (45.5%) were classified as MBI-LCBI and 24 (54.5%) were classified as non-MBI-LCBI. The primary disease type (P = 0.018), neutropenic within 3 days before CLABSI (MBI-LCBI vs. non-MBI-LCBI: 95.0% vs. 26.3%, P = <0.0001), line(s) removed owing to CLABSI (15.0% vs. 54.2%, P = 0.011) and Gram-negative organisms cultured (70.0% vs. 37.5%, P = 0.004) showed significantly difference between the groups.Conclusion
Our data showed that MBI-LCBI cases account for 45.5% of the CLABSI cases identified in blood cancer patients, and constituted a significant burden to this high-risk patient population. 相似文献Background
Extended phenotyping is one of the important method of reducing red cell alloimmunisation. Extended phenotyping of red cells from voluntary donors have many uses in addition to its application in population genetics. As there was very little data extended phenotyping on a cohort of Indian Voluntary blood donors this project was undertaken.Study design & methodology
200 regular voluntary blood donors having ‘O’ blood group were included for red cell antigen typing of Rh (D,C,E,c,e), Kell (K, k, Kpa, Kpb), Duffy (Fya, Fyb), Kidd (Jka, Jkb), Lewis(Lea, Leb), P(P1), MNS (M, N,S,s), and Lutheran (Lua, Lub), Colton (Coa, Cob), Diago (Diaa, Wra), Vw and Xga antigens using conventional antisera provided by DIAGAST. Calculations of antigen and phenotypes frequencies were expressed as percentages.Results
Out of 200 ‘O’ group blood donors, 96.5% were Rh D and 2.5% were K positive. Amongst Rh antigens, e was the most common (100%) followed by D, C (91.0%), c (50.5%) and E (16.5%) with DCe/DCe (R1R1, 48.0%) being the most common phenotype. In Kell blood group system, we found k antigen to be 100% and a rare phenotype Kp (a?+?b+) was found in 1% of the donors. For Kidd and Duffy blood group systems, Jk (a?+?b+) and Fy (a?+?b-) were the most common phenotypes (39.0% and 64.0%, respectively). In the MNS blood group system, M?+?N+ (67.5%) and S?+?s+(43.5%) were the most common phenotypes. There were antigens like Cw(3.5%), K(2.3%), Kpa(1.2%), Ina(1.0%), Vw(1.2%), Coa(4.5%), Cob(1%), Lua(1.75%), Dia+(1.2%), and Wra+(0.6%) with frequency < 5% in the donor population.Conclusion
Extensively antigen phenotypes group ‘O’ red cells showed significant variation with other population from India as well as with Caucasian and black population. Extensive phenotyping ‘O’ group regular blood donors of red cell antigens is very useful to prepare in-house red cell panels for identification of alloantibodies. 相似文献Introduction
Evidence suggests that red cell antigens may act as receptors for viruses and bacteria and therefore could be associated with HIV infection. Previous studies have been controversial and therefore the aim of this exploratory study was to analyse the expression of immunogenic red cell antigens in HIV-seropositive individuals and to compare the results to negative donors from South Africa.Methods
The expression of ABO, Rh, Kell and Duffy antigens from 119 HIV-seropositive patients was compared to 317 HIV-seronegative blood donors. Nucleic acid amplification testing and PCR were used to determine the HIV status and the ID-Gel Card Technology was used to determine the blood group antigen profile.Results
There was no significant difference in the expression of A, B, AB, Duffy or Kel antigens between the two groups but significantly lower numbers of HIV+ individuals were O Rh Negative (p?=?,0.0001). Analysis of those with a Duffy null phenotype revealed a significantly higher incidence of blood type A RH1-Positive, Dce/R0r and B RH1-Positive, DcEe/R2r within the HIV-seropositive group (p?=?<?0.05). None of the HIV-seropositive individuals were O RH1-Negative, dce/rr.Conclusion
In conclusion these initial findings have demonstrated a decreased incidence of blood type O Rh1-negative in HIV?+?individuals which suggests that red blood cell antigens may play an important role in susceptibility to HIV infection. The relationship between red cell antigens and HIV infection however remains complex and therefore larger studies are required to confirm these results. 相似文献Background
Fluid shifts from interstitial to intravascular space during blood donation helps in compensating the lost blood volume. We aimed to determine the volume of fluid shift following donation in donors with and without pre-donation fluid intake.Methods
We studied the fluid shift in 325 blood donors prospectively. Donors were divided in groups- with no fluid intake (GI) and either water (GII) or oral rehydrating fluids (GIII) before donation. Fluid shift following donation was calculated based on the difference between the pre and post donation blood volume. The influence of oral fluid intake, age, gender and body mass index (BMI) on volume of fluid shift was analyzed.Results
The fluid shift was significant between donors without fluids (GI: 127?±?81?ml) and donors with fluid intake (GII & III: 96?±?45?ml) (p?<?0.05). The difference was not significant between donors with water intake (GII: 106?±?52?ml) and oral rehydrating fluid intake (GIII: 87?±?41?ml). The shifted fluid volume increased with increasing BMI and decreased with increasing age in females. The fluid shift increased in females than in males.Conclusion
The age, gender, BMI and VVR did not significantly contribute to the volume of fluid shift following donation. As per our observation, the oral fluids before donation might not contribute to increase in fluid shift in blood donors after donation. 相似文献Areas covered: In the present review the authors have discussed a number of novel solutions utilizing a variety of molecular techniques for pathogen detection, identification and antimicrobial susceptibility. The review is not designed to be an exhaustive literature review covering all diagnostic solutions ever developed, instead the authors have focused on what they have had experience using, evaluating or currently view as new and exciting with potential to revolutionize BSI diagnosis.
The authors searched PubMed (Medline) and Google Scholar with terms: BSI, Bacteraemia, Candidaemia, Diagnostics, AST, Rapid, AMR, Novel and Blood Culture. The authors attended recent clinical microbiology technology congresses.
Expert commentary: There are multiple exciting novel technologies at differing stages of development with potential to revolutionize diagnosis of BSI. More work is needed as well as a standardized assessment of different platforms in order to better understand the clinical and financial impacts these will have in clinical microbiology laboratories. 相似文献