Donor levels of serum alanine aminotransferase activity and antibody to hepatitis B core antigen associated with recipient hepatitis C and non- B, non-C outcomes

BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little.     

Donor screening for antibody to hepatitis B core antigen and hepatitis B virus infection in transfusion recipients

BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools.     

股骨柄假体表面多孔层孔隙形状改造的动物实验

目的:观察菱形孔隙及方形孔隙两种不同几何形状多孔层设计股骨柄假体的生物学固定效果,分析孔隙几何形状对假体生物学固定的影响。方法:于2003-03/2004-04在中山大学医学部动物中心完成全部实验过程。纳入24只成年杂种犬,雌雄不拘,以随机数字表法均分为2组,即菱形孔隙组及方形孔隙组,各12只。自行设计完成犬骨重建型股骨柄假体,将股骨柄假体近2/3段表层改成两种不同几何形状的粗大多孔层结构,钛丝表面假体,钛丝直径改为1.0mm,孔径加大至5.0mm,孔隙度可达80%。菱形孔隙组钛丝沿股骨假体柄呈螺旋形排列并斜形相交,方形孔隙组钛丝沿股骨假体柄纵横排列并直角相交。均将假体表面孔隙内充填自体股骨头颈骨质制成的骨泥后,行右侧人工股骨头置换术。术后6个月行X射线摄片、组织学检查及生物力学测试,以股骨近端骨吸收情况、新生骨长入深度及孔隙充满度、假体-骨界面最大剪切强度测量为评价指标,了解假体内外成骨和固定情况。结果:菱形孔隙组及方形孔隙组各12只,实验中手术不成功或术后生存不够观察时间的均予实验过程中随时补足,最终每组12只进入结果分析。①组织学观察显示菱形孔隙组多孔层孔隙内最大骨长入深度及孔隙内新生骨平均充盈率均优于方形孔隙组(3000,2450μm;96.2%,71.6%)。②菱形孔隙组假体-骨界面最大剪切强度高于方形孔隙组,差异有显著性意义[(8.57±0.51),(3.15±0.41)N/mm2,P<0.01]。③菱形孔隙组6个月标本肉眼及X射线观察股骨近端无明显骨吸收,优于方形孔隙组;所有实验犬术后伤口缝线任其自行脱落,除1只伤口感染并于术后17d死亡外,余实验犬均伤口愈合良好,未出现不良反应。结论:股骨柄假体表面不同几何形状多孔层设计能影响其生物学固定效果,菱形孔隙设计优于方形孔隙。     

Evaluation of the sensitivity of scout radiographs on unenhanced helical CT in identifying ureteric calculi: a large UK tertiary referral centre experience

Objective

Unenhanced helical CT for kidney, ureter and bladder (CT KUB) has become the standard investigation for renal colic. This study aims to determine the sensitivity of scout radiographs in detecting ureteric calculi using CT KUB as a standard reference.

Methods

A retrospective review of consecutive patients who presented with acute flank pain and were investigated using CT KUB. 201 patients with positive ureteric calculi were included. Two radiologists independently reviewed the scout radiographs with access to CT KUB images. Each observer recorded the presence or absence of calculi, location, size and mean Hounsfield units of each calculus.

Results

203 ureteric calculi were analysed from 201 patients. The overall sensitivity of scout radiographs for Observer A was 42.3% and for Observer B 52.2%, with an interobserver reliability κ-value of 0.78. The significance of mean Hounsfield units and size between two groups of patients with visible stones and those not visible were tested; the p-value for both variables was <0.0001, which is statistically significant. The study found that calculi in the upper ureter and larger than 4 mm are more likely to be seen on the scout radiograph.

Conclusions

Usage of CT scout radiography should be encouraged and reported routinely in conjunction with CT KUB as a baseline for treatment follow-up.Unenhanced helical CT for kidney, ureter and bladder (CT KUB) has become the standard investigation for renal colic [1,2]. Its superior sensitivity and specificity has led to the demise in popularity of intravenous urogram (IVU) [3-5], although there remain some concerns about radiation dose [6]. At our institution, CT KUB has been the first-line investigation for patients suspected of having acute renal colic since 2006 [7]. Serial plain abdominal radiographs (KUB) however remain useful baseline and follow-up investigations to track the passage of stones unless the calculi are radiographically occult, in which case CT KUB or ultrasound will then be the investigations of choice.Digital CT scout radiographs are produced routinely to assist in positioning patients before axial images are acquired. They are taken from the level of the xiphoid sternum to the level of the pubic symphysis. The scout view is often overlooked and deemed not to be of diagnostic quality. However it has been proposed that careful study of the scout radiograph may identify the calculus and negate the need for a baseline plain abdominal KUB radiograph [8].In our institution, only a small number of patients who had ureteric calculi diagnosed on CT KUB had baseline plain radiographs at the same clinical presentation; the timing of the baseline plain KUB radiographs taken differs depending on varying urologists'' clinical practices. This has posed a real clinical dilemma as the absence of calculi on follow-up plain KUB taken several days after the initial presentation could be due either to the successful passage of calculi or to a radiographically occult stone. As a consequence, repeat CT KUB is occasionally performed in order to clarify the position of the calculi. We postulate that, if scout radiographs have sufficient sensitivity to detect calculi, they can be reported in conjunction with all the CT KUB examinations and patients will have a clear follow-up pathway with either plain KUB or ultrasound at the time of presentation.Although there are several recently published series that evaluate the sensitivity of scout radiographs, the number of patients used was relatively small [8-11]. The primary aim of this study was to determine the sensitivity of CT KUB scout radiographs in detecting ureteric calculi using CT KUB as a standard reference and comparing this against the recently published series. Factors that may affect the sensitivity of detection on scout radiographs will be evaluated. The secondary end point was to assess the sensitivity of plain radiographs in detecting ureteric calculi compared with scout radiographs using CT KUB as the gold standard. The potential saving on the cost of plain radiographs and radiation dose will be discussed.     

Effectiveness of near-peer simulation for managing the acutely deteriorating patient among residents of an internal medicine junior residency programme

INTRODUCTIONNear-peer teaching is gaining popularity as a teaching modality, as it improves the learner’s understanding, is targeted at an appropriate level and promotes familiarisation. This study was initiated to evaluate the effectiveness of incorporating near-peer instruction into simulation-based training within a junior residency programme.METHODS42 first-year residents from an internal medicine junior residency programme were recruited. Participants underwent a simulation-based training programme conducted over five weeks. Each week involved either an emergency or acute clinical scenario. A structured questionnaire was administered prior to and after the course to compare participants’ perceived knowledge, experience and confidence in managing the clinical scenarios.RESULTSIn our study, 83% of participants agreed/strongly agreed that the scenarios were realistic. There were improvements in perceived knowledge, experience and confidence after the course. The greatest improvement was seen for experience (post-simulation: median 7.00 [interquartile range (IQR) 6.00‒8.00] vs. pre-simulation: median 5.00 [IQR 3.00–6.25]). 65% of participants were keen to help with future training.CONCLUSIONNear-peer simulation training was found to be a viable and valuable method of instruction for first-year residents for increasing experience, instilling confidence and improving perceived knowledge. Integration of such programmes within medical education curricula shows good promise of continuity, with many first-year residents inspired to organise subsequent sessions.     

COVID-19 and ischemic stroke: a systematic review and meta-summary of the literature

Journal of Thrombosis and Thrombolysis - Acute ischemic stroke (AIS) is a life-threatening complication of coronavirus disease 2019 (COVID-19) infection. Increasing reports suggest an association...     

Acute kidney injury and extrarenal organ dysfunction: new concepts and experimental evidence

Acute kidney injury (AKI) is a frequent complication in the intensive care unit with limited therapeutic modalities. Although survival from isolated AKI has improved with recent advancements in renal replacement therapy, mortality from AKI complicated by multiorgan dysfunction has remained unchanged and is estimated to be approximately 50%. Hence, defining and better understanding the pathophysiology of distant organ dysfunction associated with AKI is clinically important because it may lead to new treatment strategies. In animal models, it has become increasingly clear that AKI is not an isolated event but results in remote organ dysfunction involving the heart, lungs, liver, intestines, and brain through an inflammatory mechanism that involves neutrophil migration, cytokine expression, and increased oxidative stress. The purpose of this brief review is to summarize the human and basic science evidence for AKI and its detrimental effects on distant organs.     

Listening to the rural health workers in Papua New Guinea - the social factors that influence their motivation to work

Despite rural health services being situated and integrated within communities in which people work and live, the complex interaction of the social environment on health worker motivation and performance in Low Middle Income Countries has been neglected in research. In this article we investigate how social factors impact on health worker motivation and performance in rural health services in Papua New Guinea (PNG). Face-to-face in-depth interviews were conducted with 33 health workers from three provinces (Central, Madang, and Milne Bay) in PNG between August and November 2009. They included health extension officers, community health workers and nursing officers, some of whom were in charge of the health centres. The health centres were a selection across church based, government and private enterprise health facilities. Qualitative analysis identified the key social factors impacting on health worker motivation and performance to be the local community context, gender roles and family related issues, safety and security and health beliefs and attitudes of patients and community members. Our study identified the importance of strong supportive communities on health worker motivation. These findings have implications for developing sustainable strategies for motivation and performance enhancement of rural health workers in resource poor settings.