Rational Classification of Portal Vein Thrombosis and Its Clinical Significance

Portal vein thrombosis (PVT) is commonly classified into acute (symptom duration <60 days and absence of portal carvernoma and portal hypertension) and chronic types. However, the rationality of this classification has received little attention. In this study, 60 patients (40 men and 20 women) with PVT were examined using contrast-enhanced computed tomography (CT). The percentage of vein occlusion, including portal vein (PV) and superior mesenteric vein (SMV), was measured on CT image. Of 60 patients, 17 (28.3%) met the criterion of acute PVT. Symptoms occurred more frequently in patients with superior mesenteric vein thrombosis (SMVT) compared to those without SMVT (p<0.001). However, there was no significant difference in PV occlusion between patients with and without symptoms. The frequency of cavernous transformation was significantly higher in patients with complete PVT than those with partial PVT (p<0.001). Complications of portal hypertension were significantly associated with cirrhosis (p<0.001) rather than with the severity of PVT and presence of cavernoma. These results suggest that the severity of PVT is only associated with the formation of portal cavernoma but unrelated to the onset of symptoms and the development of portal hypertension. We classified PVT into complete and partial types, and each was subclassified into with and without portal cavernoma. In conclusion, neither symptom duration nor cavernous transformation can clearly distinguish between acute and chronic PVT. The new classification system can determine the pathological alterations of PVT, patency of portal vein and outcome of treatment in a longitudinal study.     

Gustatory imagery reveals functional connectivity from the prefrontal to insular cortices traced with magnetoencephalography

Our experience and prejudice concerning food play an important role in modulating gustatory information processing; gustatory memory stored in the central nervous system influences gustatory information arising from the peripheral nervous system. We have elucidated the mechanism of the “top-down” modulation of taste perception in humans using functional magnetic resonance imaging (fMRI) and demonstrated that gustatory imagery is mediated by the prefrontal (PFC) and insular cortices (IC). However, the temporal order of activation of these brain regions during gustatory imagery is still an open issue. To explore the source of “top-down” signals during gustatory imagery tasks, we analyzed the temporal activation patterns of activated regions in the cerebral cortex using another non-invasive brain imaging technique, magnetoencephalography (MEG). Gustatory imagery tasks were presented by words (Letter G-V) or pictures (Picture G-V) of foods/beverages, and participants were requested to recall their taste. In the Letter G-V session, 7/9 (77.8%) participants showed activation in the IC with a latency of 401.7±34.7 ms (n = 7) from the onset of word exhibition. In 5/7 (71.4%) participants who exhibited IC activation, the PFC was activated prior to the IC at a latency of 315.2±56.5 ms (n = 5), which was significantly shorter than the latency to the IC activation. In the Picture G-V session, the IC was activated in 6/9 (66.7%) participants, and only 1/9 (11.1%) participants showed activation in the PFC. There was no significant dominance between the right and left IC or PFC during gustatory imagery. These results support those from our previous fMRI study in that the Letter G-V session rather than the Picture G-V session effectively activates the PFC and IC and strengthen the hypothesis that the PFC mediates “top-down” control of retrieving gustatory information from the storage of long-term memories and in turn activates the IC.     

两种介入途径治疗急性、亚急性门静脉及肠系膜上静脉血栓的临床疗效分析

目的：评价介入技术治疗急性和亚急性门静脉（portal vein,PV）及肠系膜上静脉（superior mesenterie vein, SMV）血栓形成的临床疗效。方法：对28例治疗急性和亚急性（发病一周至一月）的PV及SMV血栓患者进行介入治疗。按介入治疗途径不同分为下述两组：选择经颈静脉穿刺门静脉（transjugular intrahepatic portosystemic shunt , TIPS途径）置管溶栓（19例）和经皮穿肝内门脉（percutaneous transhepatic）置管溶栓治疗（9例）。结果：所有患者随访一周至三个月,其中治疗成功24例,临床症状明显改善,无严重并发症。经TIPS途径治疗的患者组中,16例随访显示大部分血栓被清除,门静脉系统有血流通过,临床症状缓解。3例SMV及PV恢复部分血流,但临床症状无明显改善。经皮穿肝内门脉直接置管溶栓治疗组中,6例患者的PV及SMV内血栓大部分清除,血流基本改善,2例患者PV及SMV血流部分好转,临床症状无明显改善,严重并发症1例（术后两天死于腹腔出血）。结论：经TIPS途径介入技术和经皮穿肝内门脉直接置管溶栓治疗是治疗急性和亚急性PV及SMV血栓形成的有效方法,前者的疗效及安全性均好于后者。     

Combined Hepatic Vein, Umbilicoportal Vein, and Superior Mesenteric Artery Catheterization in Portal Hypertension: Estimation of the Portal Fraction of Total Hepatic Blood Flow in Cirrhotic Patients

Hemodynamic data were obtained in 13 cirrhotic patients with severe portal hypertension, undergoing combined hepatic vein, umbilicoportal vein, and superior mesenteric artery catheterization. The relative clearance of indocyanine green, the portohepatic gradient (difference between the free portal venous pressure and the free hepatic venous pressure), and the estimated hepatic blood flow were measured. The portal fraction (PF) of total hepatic blood flow was calculated in all patients using indicator dilution curves obtained from the portal bifurcation, a right hepatic vein, and when possible a left hepatic vein (six cases) after injection of ⁵¹Cr-labeled red blood cells (⁵¹Cr RBC) into the superior mesenteric artery. Flows were overestimated because of loss of indicator through spontaneous portosystemic shunts; however, the ratio between hepatic and portal indicator dilution curves can be used to calculate the portal fraction of total hepatic blood flow since no extrahepatic shunts existed after the bifurcation of the portal vein (as shown on portography). In 10 patients, 15 series of curves were calculable and the PF varied between 30.1 and 100% (mean ± SE: 71.1 ± 6.2%). In the three other patients, only delayed activity from recirculation was detected from portal and hepatic vein samples and PF was 0%; in these three cases, portography and arteriography revealed spontaneous portacaval shunting with reverse and/or stagnant circulation in the portal vein. In the 13 patients, no correlation existed between PF and the relative clearance of indocyanine green or the portohepatic gradient, parameters generally used as indices of severity in cirrhosis. In 10 patients, no correlation was found between PF and the estimated hepatic blood flow.     

Selective portal vein embolization as introduction in major surgery

In the period between the December 2000 and September 2004, altogether 13 patients underwent preoperative portal vein embolization (PPVE); 9 patients with colorectal metastases and 4 patients with hepatocellular carcinoma. The indirect splenic portography was performed after catheter was introduced into superior mesenteric artery via femoral artery approach. The portal vein was punctured percutaneously transhepatic under fluoroscopy. Following portography, selected portal vein segments were embolized by injecting polyvinil alcohol (PVA) particles until stasis of blood flow was achieved. Proximal parts of branches and the channel in the liver parenchyma were occluded with Gelfoam particles. The increase of the remnant liver parenchyma was measured by magnetic resonance imaging. iTwo patients experienced post-embolization syndrome and another one had subcapsular hematoma. The volume of the liver parenchyma increased minimally for 8% and maximally for 109%. Altogether, 10 patients underwent surgical resection. In two patients, the disease progressed and carcinoma spread to the previously healthy liver lobe and in one there was no hypertrophy and we decided for artery chemoembolization (AC). The results show that PPVE triggers a strong regenerative response resulting in hypertrophy of normal liver parenchyma and expand possibilities of curative surgery for patients who would not otherwise have been candidates for extended resection.     

多层螺旋CT门静脉成像在评估肝硬化门脉侧枝血管中的价值

目的：评价多层螺旋CT门静脉成像显示门静脉高压的价值。材料与方法：30例门脉高压患者进行了螺旋CT门脉成像检查,其中10例患者又进行了门静脉造影检查(间接法)。30例患者中全部存在侧枝循环,多数病例有2个或2个以上部位侧枝循环。结果：多层螺旋CT门静脉成像不仅显示了肝内门静脉2-3级分支,还显示了整套门脉侧枝血管系统。在三维门脉像上,脾门静脉曲张29例(占96．7％),其中1例脾静脉因栓子部分闭塞而狭窄,另有1例则完全栓塞血管未显示。胃左静脉曲张28例(占93％),食管或食管旁静脉曲张27例(占90％),胃短静脉(胃后静脉)曲张19例(占63％),胃肾分流血管10例(占33％),腹膜后静脉曲张9例(占30％),脐周静脉曲张伴腹壁静脉曲张6例(占20％)。10例患者CT三维门脉像与间接门静脉造影作比较,前者对门静脉及其侧枝循环的显示好于后者。结论：多层螺旋CT门脉成像是门静脉无创性检查的可靠方法,有较高的临床运用价值。     

环颈雉胃的血供

用血管铸型法和大体解剖学方法对环颈雉胃动脉的起源、分布及胃静脉的回流情况进行了解剖学研究。结果表明,环颈雉的胃动脉均由腹腔动脉分出;腺胃由腺胃背侧动脉和腺胃腹侧动脉营养,腺胃背侧动脉直接起自腹腔动态的左侧,腺胃腹侧动脉起自腹腔动脉左支。腺胃血液的静脉有腺胃前静脉和腺胃后静脉,分别汇入后腔静脉和左肝门静脉。肌胃由肌胃左动脉、肌胃右动脉和肌胃背侧动脉营养,肌胃左动脉起自腹腔动脉的左支;肌胃右动脉起自腹腔动脉的右支;肌胃背侧动脉从腺胃背动脉分支而来。回流肌胃血液的静脉有胃右静脉、胃左静脉和胃腹侧静脉;胃右静脉汇入右肝门静脉,胃左静脉和胃腹侧静脉汇入左肝门静脉。另外腺胃和肌胃的表面缺乏主干动脉间的吻合。     

Hepatoportography via the Umbilical Vein: A Superior Approach to Diagnosis in Liver Disease

The umbilical vein in adults is patent but collapsed. There is a membranous valve at its entrance into the left portal vein. Cannulation of the portal vein via the umbilical vein permits direct access to the portal system for portography and hepatography. This procedure was performed under local or general anesthesia in 30 patients and was successful in 22. It is useful in the investigation of patients with portal hypertension, and suspected intrahepatic tumours or abscesses. It gives excellent contrast visualization of the liver and definition of lesions as small as 1.0 cm. This technique is superior to both hepatic scanning and splenoportography.     

对比分析多种介入途径治疗门静脉系统血栓的临床疗效

目的：对比分析多种介入途径治疗门静脉系统血栓的临床疗效。方法：收集从2001年1月至2009年3月经我科治疗的37例门静脉系统（包括门静脉、肠系膜上、下静脉及脾静脉）血栓形成患者,根据介入治疗途径的不同分为三组：A组（13例）行经TIPS途径门静脉行碎栓溶栓及置管溶栓术;B组（19例）行直接经皮穿肝门静脉碎栓和或置管溶栓术;C组（5例）行经肠系膜上动脉置管溶栓治疗。所有的患者术后定期随访1—12个月,复查CT或彩超了解门静脉系统的血流变化及临床症状恢复情况。结果：A组：经治疗出院时11例（85％）患者门静脉完全再通,;1例（8％）门静脉血流部分再通,1例（8％）术后第二天因出血死亡。术后随访1、3、6、12月门静脉通畅率分别为：85％,77％,77％,62％;所有患者的临床症状均明显缓解。B组：经治疗出院时7例（37％）门静脉完全再通,9例（47％）部分再通,3例（16％）因出血中止溶栓;随访1、3、6月、12月门静脉通畅率分别为：32％,26％,16％,16％。C组：经治疗出院时5例（100％）患者门静脉均未再通,通畅率为0％,术后随访1-3个月内4例患者I临床症状得到部分缓解。结论：经TIPS途径治疗后门静脉的再通率及临床症状改善均好于直接经皮穿肝及经肠系膜上动脉途径。经肠系膜上动脉置管溶栓法无法使已有侧支形成的门静脉主干复通,仅能一定程度缓解患者的临床症状。     

3D打印技术在周围型肺癌手术规划中的应用

目的:通过比较计算机断层扫描,三维重建图像和3D打印在手术中显示肺动脉分支的能力,探讨3D打印技术在周围型肺癌手术规划中的应用价值。方法:2018年1月-2018年12月,同一胸外科治疗组中接受电视胸腔镜择期右肺上叶切除手术的周围型肺癌患者30例。随机分为3组,每组10例,分别通过计算机断层扫描,三维重建图像和3D打印进行术前手术规划。分别记录每组手术规划中的右肺上叶动脉分支数目,然后将这些记录与术中实际所见进行比较。结果:各组间患者一般资料无统计学差异。所有患者均有完整的CT扫描、三维重建、3D打印和术中动脉分支数据,且都接受了VATS解剖性右肺上叶切除术,术中进行顺利,无中转开胸,无术中大出血,术后无明显并发症和围手术期死亡,皆顺利出院。CT组的右肺上叶动脉分支数量为1.5±0.52,3DI组为2.1±0.57,3DP组为2.2±0.63。CT组、3DI组和3DP组分别与手术中所见比较,CT组存在统计学差异(P=0.025),其他两组无统计学意义。结论:3D打印技术在周围型肺癌手术规划中的效果优于计算机断层扫描,比三维重建图像更加直观,建议推广。     

What Will It Take to Eliminate Pediatric HIV? Reaching WHO Target Rates of Mother-to-Child HIV Transmission in Zimbabwe: A Model-Based Analysis

Background

The World Health Organization (WHO) has called for the “virtual elimination” of pediatric HIV: a mother-to-child HIV transmission (MTCT) risk of less than 5%. We investigated uptake of prevention of MTCT (PMTCT) services, infant feeding recommendations, and specific drug regimens necessary to achieve this goal in Zimbabwe.

Methods and Findings

We used a computer model to simulate a cohort of HIV-infected, pregnant/breastfeeding women (mean age, 24 y; mean CD4, 451/µl; breastfeeding duration, 12 mo). Three PMTCT regimens were evaluated: (1) single-dose nevirapine (sdNVP), (2) WHO 2010 guidelines'' “Option A” (zidovudine in pregnancy, infant nevirapine throughout breastfeeding for women without advanced disease, lifelong combination antiretroviral therapy for women with advanced disease), and (3) WHO “Option B” (pregnancy/breastfeeding-limited combination antiretroviral drug regimens without advanced disease; lifelong antiretroviral therapy with advanced disease). We examined four levels of PMTCT uptake (proportion of pregnant women accessing and adhering to PMTCT services): reported rates in 2008 and 2009 (36% and 56%, respectively) and target goals in 2008 and 2009 (80% and 95%, respectively). The primary model outcome was MTCT risk at weaning.The 2008 sdNVP-based National PMTCT Program led to a projected 12-mo MTCT risk of 20.3%. Improved uptake in 2009 reduced projected risk to 18.0%. If sdNVP were replaced by more effective regimens, with 2009 (56%) uptake, estimated MTCT risk would be 14.4% (Option A) or 13.4% (Option B). Even with 95% uptake of Option A or B, projected transmission risks (6.1%–7.7%) would exceed the WHO goal of less than 5%. Only if the lowest published transmission risks were used for each drug regimen, or breastfeeding duration were shortened, would MTCT risks at 95% uptake fall below 5%.

Conclusions

Implementation of the WHO PMTCT guidelines must be accompanied by efforts to improve access to PMTCT services, retain women in care, and support medication adherence throughout pregnancy and breastfeeding, to approach the “virtual elimination” of pediatric HIV in Zimbabwe. Please see later in the article for the Editors'' Summary     

SPY Imaging Assessment Correlates With Transesophageal Echocardiogram Assessment of Ventricular Function During Off-Pump Coronary Artery Bypass Grafting

Intraoperative assessment of graft anastomoses is commonly performed after off-pump coronary artery bypass grafting (OPCAB). The SPY imaging system allows intraoperative graft assessment. We document correlation between intraoperative SPY images and wall motion abnormality by transesophageal echocardiogram (TEE) during OPCAB. A 79-year-old female underwent OPCAB. Intraoperative graft patency assessment was performed with the SPY and left ventricular wall motion was assessed by TEE. SPY imaging demonstrated poor flow trough the distal vein graft anastomosis to the posterior descending artery, which correlated with a new posterior wall motion hypokinesis. After graft revision, SPY imaging demonstrated good distal flow and the TEE demonstrated normalization of the left ventricular posterior wall motion. SPY technology allows the surgeon to accurately assess graft patency intraoperatively and allows immediate correction of a technical problem.     

Patency of different arterial and venous end-to-side microanastomosis techniques in a rat model

Microvascular anastomotic patency is the most important factor in determining a successful outcome in free-flap transfers. End-to-end and end-to-side techniques have been shown to provide equivalent arterial patency rates in clinical and basic science studies, and end-to-side anastomoses have been used extensively in microsurgical reconstruction. Nevertheless, the effect of venotomy shape on the patency of venous end-to-side anastomoses has not been previously reported. The purpose of this study was to compare the patency rates of end-to-side anastomoses using different techniques in both arteries and veins. In total, 104 Sprague-Dawley rats were subdivided into four groups. The rats were anesthetized, and anastomosis was performed on either the femoral artery or vein on the right with the left used as control. Vesselotomy was varied between an end-to-side hole and an end-to-side slit with patency measured immediately following surgery and at 2 weeks. No significant difference in patency or histology between these techniques was demonstrated in any group. We conclude there is no difference in patency rate between the two techniques in arterial or venous vesselotomies; however, in small vessels < 1.5 mm, the slit technique is technically easier, and clinical recommendations are given.     

Retention in care and connection to care among HIV-infected patients on antiretroviral therapy in Africa: estimation via a sampling-based approach

Introduction

Current estimates of retention among HIV-infected patients on antiretroviral therapy (ART) in Africa consider patients who are lost to follow-up (LTF) as well as those who die shortly after their last clinic visit to be no longer in care and to represent limitations in access to care. Yet many lost patients may have “silently” transferred and deaths shortly after the last clinic visit more likely represent limitations in clinical care rather than access to care after initial linkage.

Methods

We evaluated HIV-infected adults initiating ART from 1/1/2004 to 9/30/2007 at a clinic in rural Uganda. A representative sample of lost patients was tracked in the community to obtain updated information about care at other ART sites. Updated outcomes were incorporated with probability weights to obtain “corrected” estimates of retention for the entire clinic population. We used the competing risks approach to estimate “connection to care”—the percentage of patients accessing care over time (including those who died while in care).

Results

Among 3,628 patients, 829 became lost, 128 were tracked and in 111, updated information was obtained. Of 111, 79 (71%) were alive and 35/48 (73%) of patients interviewed in person were in care and on ART. Patient retention for the clinic population assuming lost patients were not in care was 82.3%, 68.9%, and 60.1% at 1, 2 and 3 years. Incorporating updated care information from the sample of lost patients increased estimates of patient retention to 85.8% to 90.9%, 78.9% to 86.2% and 75.8% to 84.7% at the same time points.

Conclusions

Accounting for “silent transfers” and early deaths increased estimates of patient retention and connection to care substantially. Deaths soon after the last clinic visit (potentially reflecting limitations in clinical effectiveness) and disconnection from care among patient who were alive each accounted for approximately half of failures of retention.     

TSH-CHECK-1 test: diagnostic accuracy and potential application to initiating treatment for hypothyroidism in patients on anti-tuberculosis drugs

Background

Thyroid-stimulating hormone (TSH) promotes expression of thyroid hormones which are essential for metabolism, growth, and development. Second-line drugs to treat tuberculosis (TB) can cause hypothyroidism by suppressing thyroid hormone synthesis. Therefore, TSH levels are routinely measured in TB patients receiving second-line drugs, and thyroxin treatment is initiated where indicated. However, standard TSH tests are technically demanding for many low-resource settings where TB is prevalent; a simple and inexpensive test is urgently needed.

Methods

As a proof of concept study TSH was measured in routinely collected sera at the University Medical Center Utrecht, Netherlands, using the TSH-CHECK-1 (VEDALAB, Alençon, France), a lateral-flow rapid immunochromatographic assay with a TSH cut-off value of 10 µIU/mL, the standard threshold for initiating treatment. These results were compared with TSH levels measured by a reference standard (UniCel DXi 800 imunoassay system, Beckman Coulter, USA). Sensitivity, specificity, and likelihood ratios were then calculated.

Results

A total of 215 serum samples were evaluated: 107 with TSH values <10 µIU/mL and 108 with values ≥10 µIU/mL. TSH-CHECK-1 test sensitivity was found to be 100.0% (95% CI: 96.6–100.0) and specificity was 76.6% (95% CI: 67.5–84.3). Predictive values (PV) were modelled for different levels of prevalence. For a prevalence of 10% and 50%, the positive PV was 32.2% (95% CI: 25.0–39.7%) and 81.1% (95% CI: 75.0–85.5%), respectively; the negative PV was 100% (95% CI: 98.9–100%) and 100% (95% CI: 91.3–100%) respectively.

Discussion/Conclusions

The TSH-CHECK-1 rapid test was practical and simple to perform but difficult to interpret on weak positive results. All sera with TSH≥10 µIU/mL were correctly identified, but the test lacked sufficient specificity. Given its excellent negative PV in this evaluation, the test shows promise for ruling out hypothyroidism. However, so far it appears that samples testing positive with TSH-CHECK-1 would require confirmation using another method.     

一雄性灰鹤胃的血液供应

用血管铸型法对一只因伤致死的雄性灰鹤胃的血供进行铸型观察,结果显示,灰鹤的胃动脉均由腹腔动脉分出,腺胃由腺胃背侧动脉和腺胃腹侧动脉供应营养,肌胃由胃左动脉、胃右动脉和肌胃背侧动脉供应营养。腺胃的静脉有腺胃腹侧静脉、胃凹腹侧静脉和腺胃背侧静脉,分别经左（腺胃腹侧静脉和胃凹腹侧静脉）、右（腺胃背侧静脉）肝门静脉回流;肌胃的静脉有胃左静脉、胃右静脉和胃背侧静脉,分别经左（胃左静脉）、右（胃右静脉和肌胃背侧静脉）肝门静脉回流。此外本文将灰鹤胃的血供与其它动物的进行了比较。     

Early experience with computed tomographic angiography in microsurgical reconstruction

Preoperative angiography is frequently used in the planning of microsurgical reconstruction. However, several potentially devastating complications can result from angiography, including arterial occlusion and pseudoaneurysm. Computed tomographic angiography is a relatively new technique that can provide detailed information about vascular anatomy as well as soft and bony tissue without the risks of traditional angiography. In addition, three-dimensional image reconstruction uniquely demonstrates anatomical relationships among blood vessels, bones, and soft tissue. Fourteen computed tomographic angiograms were obtained in 10 patients undergoing microsurgical reconstruction of the head and neck, lower extremity, or upper extremity. The average patient age was 46.9 years (range, 22 to 67 years). Charges related to the computed tomographic procedure were compared with those of conventional preoperative imaging for microsurgical repair. At our institution, the average computed tomographic angiogram charge was 1140 US dollars, whereas the average charge for traditional arteriography was 3900 US dollars. When compared with intraoperative evaluation, computed tomographic angiograms demonstrated clinically relevant surgical anatomy. No complications were noted for the radiographic procedure or after free flap reconstruction. Computed tomographic angiography provides high-resolution, three-dimensional arterial, venous, and soft-tissue imaging without the risks of traditional angiogram and at a lower cost.     

Pandemics in the age of Twitter: content analysis of Tweets during the 2009 H1N1 outbreak

Background

Surveys are popular methods to measure public perceptions in emergencies but can be costly and time consuming. We suggest and evaluate a complementary “infoveillance” approach using Twitter during the 2009 H1N1 pandemic. Our study aimed to: 1) monitor the use of the terms “H1N1” versus “swine flu” over time; 2) conduct a content analysis of “tweets”; and 3) validate Twitter as a real-time content, sentiment, and public attention trend-tracking tool.

Methodology/Principal Findings

Between May 1 and December 31, 2009, we archived over 2 million Twitter posts containing keywords “swine flu,” “swineflu,” and/or “H1N1.” using Infovigil, an infoveillance system. Tweets using “H1N1” increased from 8.8% to 40.5% (R ² = .788; p<.001), indicating a gradual adoption of World Health Organization-recommended terminology. 5,395 tweets were randomly selected from 9 days, 4 weeks apart and coded using a tri-axial coding scheme. To track tweet content and to test the feasibility of automated coding, we created database queries for keywords and correlated these results with manual coding. Content analysis indicated resource-related posts were most commonly shared (52.6%). 4.5% of cases were identified as misinformation. News websites were the most popular sources (23.2%), while government and health agencies were linked only 1.5% of the time. 7/10 automated queries correlated with manual coding. Several Twitter activity peaks coincided with major news stories. Our results correlated well with H1N1 incidence data.

Conclusions

This study illustrates the potential of using social media to conduct “infodemiology” studies for public health. 2009 H1N1-related tweets were primarily used to disseminate information from credible sources, but were also a source of opinions and experiences. Tweets can be used for real-time content analysis and knowledge translation research, allowing health authorities to respond to public concerns.     

A cost-effectiveness analysis of "test" versus "treat" patients hospitalized with suspected influenza in Hong Kong

Background

Seasonal and 2009 H1N1 influenza viruses may cause severe diseases and result in excess hospitalization and mortality in the older and younger adults, respectively. Early antiviral treatment may improve clinical outcomes. We examined potential outcomes and costs of test-guided versus empirical treatment in patients hospitalized for suspected influenza in Hong Kong.

Methods

We designed a decision tree to simulate potential outcomes of four management strategies in adults hospitalized for severe respiratory infection suspected of influenza: “immunofluorescence-assay” (IFA) or “polymerase-chain-reaction” (PCR)-guided oseltamivir treatment, “empirical treatment plus PCR” and “empirical treatment alone”. Model inputs were derived from literature. The average prevalence (11%) of influenza in 2010–2011 (58% being 2009 H1N1) among cases of respiratory infections was used in the base-case analysis. Primary outcome simulated was cost per quality-adjusted life-year (QALY) expected (ICER) from the Hong Kong healthcare providers'' perspective.

Results

In base-case analysis, “empirical treatment alone” was shown to be the most cost-effective strategy and dominated the other three options. Sensitivity analyses showed that “PCR-guided treatment” would dominate “empirical treatment alone” when the daily cost of oseltamivir exceeded USD18, or when influenza prevalence was <2.5% and the predominant circulating viruses were not 2009 H1N1. Using USD50,000 as the threshold of willingness-to-pay, “empirical treatment alone” and “PCR-guided treatment” were cost-effective 97% and 3% of time, respectively, in 10,000 Monte-Carlo simulations.

Conclusions

During influenza epidemics, empirical antiviral treatment appears to be a cost-effective strategy in managing patients hospitalized with severe respiratory infection suspected of influenza, from the perspective of healthcare providers in Hong Kong.     

Acceptability of Carraguard vaginal microbicide gel among HIV-infected women in Chiang Rai, Thailand

Background

Few studies of microbicide acceptability among HIV-infected women have been done. We assessed Carraguard® vaginal gel acceptability among participants in a randomized, controlled, crossover safety trial in HIV-infected women in Thailand.

Methodology/Principal Findings

Participants used each of 3 treatments (Carraguard gel, methylcellulose placebo gel, and no product) for 7 days, were randomized to one of six treatment sequences, and were blinded to the type of gel they received in the two gel-use periods. After both gel-use periods, acceptability was assessed by face-to-face interview. Responses were compared to those of women participating in two previous Carraguard safety studies at the same study site. Sixty women enrolled with a median age of 34 years; 25% were sexually active. Self-reported adherence (98%) and overall satisfaction rating of the gels (87% liked “somewhat” or “very much”) were high, and most (77%) considered the volume of gel “just right.” For most characteristics, crossover trial participants evaluated the gels more favorably than women in the other two trials, but there were few differences in the desired characteristics of a hypothetical microbicide. Almost half (48%) of crossover trial participants noticed a difference between Carraguard and placebo gels; 33% preferred Carraguard while 12% preferred placebo (p = 0.01).

Conclusions/Significance

Daily Carraguard vaginal gel use was highly acceptable in this population of HIV-infected women, who assessed the gels more positively than women in two other trials at the site. This may be attributable to higher perceived need for protection among HIV-infected women, as well as to study design differences. This trial was registered in the U.S. National Institutes of Health clinical trials registry under registration number {"type":"clinical-trial","attrs":{"text":"NCT00213044","term_id":"NCT00213044"}}NCT00213044.