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H. Liu H. Zhang G. Wan Y. Sang Y. Chang X. Wang H. Zeng 《Journal of viral hepatitis》2014,21(7):499-507
Acute‐on‐chronic hepatitis B liver failure (ACHBLF) has a poor prognosis in patients with hepatitis B virus infection. The role of the neutrophil–lymphocyte ratio (NLR), which reflects the inflammatory status of the patient before treatment, has never been studied in this setting. To investigate the predictive value of NLR in patients with ACHBLF, a retrospective cohort with 216 patients and a prospective validation cohort with 73 patients were recruited. Multivariate analyses showed that total bilirubin (TBIL), NLR, age and model for end‐stage liver disease (MELD) score had prognostic significance for survival. Both NLR (0.781) and MELD score (0.744) had higher ROC curves, which differed significantly from those for age (0.615) and TBIL (0.691), but not from each other (P = 0.94). NLR ≤2.36 predicted lower mortality (with 91.6% sensitivity and 86.0% negative predictive value), and NLR >6.12 was a warning sign for higher mortality risk (with 90.1% specificity and 80.3% positive predictive value). These results demonstrated that pretreatment NLR was associated with the prognosis of patients with ACHBLF, and elevated NLR predicted poor outcome within 8 weeks. We suggest that NLR cut‐offs of ≤2.36 and >6.12 are powerful markers for predicting mortality in ACHBLF. 相似文献
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Beng H. Chong 《International journal of laboratory hematology》2020,42(Z1):25-32
Heparin‐induced thrombocytopenia (HIT) is an immune reaction to heparin. It often causes severe thrombosis which may lead to limb gangrene and thrombosis‐associated death. The concept of its pathogenesis has been evolving during the past five decades. Initially, HIT was thought to be caused by disseminated intravascular coagulation. Later it became clear that HIT was mediated by an immune mechanism whereby an IgG antibody induced platelet aggregation, release of procoagulant materials and consequently thrombus formation. The antigen comprises Platelet Factor 4 (PF4) and heparin which have a tendency to form ultralarge complexes. The HIT immune response has atypical features. IgG antibody appears early without IgM precedence and lasts transiently. One explanation is that there is prior priming by bacterial infection. Another unique characteristic is that it is processed as if it is a particulate antigen involving complement activation and B cells. Antigen‐presenting cells/monocytes are also involved but the role of T cells is controversial. Recent advances have provided new insights into the underlying mechanisms of HIT‐related thrombosis. Previously, platelets were believed to play a central role; their activation and consequently the induction of blood coagulation was the basis of the hypercoagulability in HIT. More recently, several studies have provided clear evidence that neutrophil and NETosis, monocytes and endothelial cells contribute significantly to the thrombosis in HIT. These new insights may result in development of better diagnostic laboratory assays and more effective treatments for HIT. 相似文献
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Hee-Jin Park You-Jung Ha Jung-Yoon Pyo Yong-Beom Park Soo-Kon Lee Sang-Won Lee 《Yonsei medical journal》2014,55(3):753-759
Purpose
To investigate clinical implications of delta neutrophil index (DNI) to discriminate adult onset Still''s disease (AOSD) from sepsis.Materials and Methods
We reviewed the medical records of 13 patients with AOSD and 33 gender and age-matched patients with sepsis. In all subjects, microbial tests were performed to exclude or confirm sepsis. All laboratory data were measured two or three times during the first 3 days and represented by their mean levels. DNI was measured automatically by ADVIA 2120 for the first 3 days.Results
There were no significant differences in white blood cell counts, neutrophil proportion, erythrocyte sedimentation rate and C-reactive protein between two groups. AOSD patients had notably lower DNI than sepsis patients regardless of the presence of bacteremia or not. However, both DNI and ferritin were not significant independent factors for predicting sepsis in the multivariate logistic regression analysis. Meanwhile, the area under the receiver operating characteristic curve (AUROC) of DNI was slightly higher than that of ferritin. When we set DNI of 2.75% as the cut-off value for predicting sepsis, 11 (84.6%) of AOSD patients had a DNI value below 2.75% and 2 (15.4%) of them had a DNI over 2.75% (relative risk for sepsis 176).Conclusion
We suggest that DNI may be a useful marker for differential diagnosis of AOSD from sepsis in the early phase as supplementary to ferritin. 相似文献98.
M. Kolpen T. Bjarnsholt C. Moser C. R. Hansen L. F. Rickelt M. Kühl C. Hempel T. Pressler N. Høiby P. Ø. Jensen 《Clinical and experimental immunology》2014,177(1):310-319
Chronic Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) patients is characterized by persisting mucoid biofilms in hypoxic endobronchial mucus. These biofilms are surrounded by numerous polymorphonuclear leucocytes (PMNs), which consume a major part of present molecular oxygen (O2) due to production of superoxide (O2−). In this study, we show that the PMNs also consume O2 for production of nitric oxide (NO) by the nitric oxide synthases (NOS) in the infected endobronchial mucus. Fresh expectorated sputum samples (n = 28) from chronically infected CF patients (n = 22) were analysed by quantifying and visualizing the NO production. NO production was detected by optode measurements combined with fluorescence microscopy, flow cytometry and spectrophotometry. Inhibition of nitric oxide synthases (NOS) with NG-monomethyl-L-arginine (L-NMMA) resulted in reduced O2 consumption (P < 0·0008, n = 8) and a lower fraction of cells with fluorescence from the NO-indicator 4-amino-5-methylamino-2′,7′-difluorofluorescein diacetate (DAF-FM) (P < 0·002, n = 8). PMNs stained with DAF-FM and the superoxide indicator hydroethidine (HE) and host cells with inducible NOS (iNOS) were identified in the sputum. In addition, the production of the stable end-products of NO in CF sputum was correlated with the concentration of PMNs; NO3− (P < 0·04, r = 0·66, n = 10) and NO2− (P< 0·006, r = 0·78, n = 11). The present study suggests that besides consumption of O2 for production of reactive oxygen species, the PMNs in CF sputum also consume O2 for production of NO. 相似文献
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目的 探讨2型糖尿病患者尿微量白蛋白/尿肌酐比值(uACR)与血糖波动的影响因素。方法
选取339例确诊的2型糖尿病患者,应用动态血糖监测系统监测血糖,收集其临床资料。首先依据平均血糖波动幅度(MAGE)分组,MAGE<3.9?mmol/L 99例(血糖波动正常组),MAGE≥3.9?mmol/L 240例(血糖波动异常组),分析影响血糖波动的因素;再依据uACR分组,uACR<30?mg/g 197例(uACR正常组),uACR≥30?mg/g 142例(uACR异常组),分析影响uACR的因素。结果 血糖波动正常组与血糖波动异常组比较,病程、空腹血糖、糖化血红蛋白、总胆固醇、中性粒细胞/淋巴细胞比值(NLR)、uACR差异有统计学意义(P?<0.05)。糖尿病病程[OlR=1.040(95% CI:0.958,1.758)]、总胆固醇[OlR=1.332(95% CI:1.061,1.672)]是血糖波动的影响因素。uACR正常组与uACR异常组比较,年龄、病程、低密度脂蛋白胆固醇、NLR、MAGE差异有统计学意义(P?<0.05)。病程[OlR=1.055(95% CI:1.014,1.096)]、NLR [OlR=2.186(95% CI:1.602,2.983)]、MAGE [OlR=1.438(95% CI:1.226,1.688)]是uACR的影响因素。结论 随着2型糖尿病患者病程的进展,血糖波动幅度逐渐增大,总胆固醇可影响血糖波动;随着病情的进展,机体的炎症反应增强,血糖波动幅度的增大可影响uACR。 相似文献
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