基于动态对比增强MRI影像组学模型预测乳腺癌新辅助化疗后非病理完全缓解

目的 观察基于动态对比增强MRI （DCE-MRI）影像组学模型预测乳腺癌新辅助化疗（NAC）后非病理完全缓解（non-pCR）的价值。方法 回顾性分析144例经病理证实并接受NAC的乳腺癌患者,按照7[DK （]∶[DK）]3比例将其分入训练组（n=99）和验证组（n=45）,比较2组病理完全缓解（pCR）与non-pCR患者临床病理指标的差异。以MaZda软件提取4个周期NAC后DCE-MRI所示病灶纹理特征,以最小绝对收缩与选择算子（LASSO）算法及十折交叉验证法筛选最优特征参数,建立影像组学标签。采用多因素Logistic回归法构建包含影像组学标签和差异具有统计学意义的临床病理指标在内的联合预测模型,以受试者工作特征（ROC）曲线评价影像组学标签及模型预测乳腺癌患者NAC non-pCR的效能。结果 训练组36例pCR、63例non-pCR,验证组分别为15例和30例。2组pCR与non-pCR患者间孕激素受体（PR）、人类表皮生长因子受体2（HER2）和细胞增殖核抗原（Ki-67）表达差异均有统计学意义（P均<0.05）。共筛选出8个最优特征参数建立影像组学标签,以之预测训练组和验证组患者NAC后non-pCR的曲线下面积（AUC）分别为0.85和0.84;而以联合预测模型预测训练组患者NAC后non-pCR的AUC、敏感度、特异度分别为0.90、88.89%及83.33%,验证组分别为0.89、83.33%及86.67%。结论 基于DCE-MRI的影像组学模型对预测乳腺癌NAC后non-pCR具有一定价值。     

基于X线及超声乳腺影像报告和数据系统构建机器学习模型预测乳腺癌分子分型

目的 观察基于X线及超声的乳腺影像报告和数据系统（BI-RADS）选取影像学特征构建的机器学习模型预测乳腺癌分子分型的可行性。方法 回顾性分析200例经病理的浸润性乳腺癌，根据免疫组织化学结果分为Luminal组（n=109）与非Luminal组（n=91），组内按7 ：3比例随机分为训练亚组及测试亚组。采集11个临床信息，并提取24个影像学特征，建立4种机器学习模型，通过受试者工作特征（ROC）曲线评价各模型预测不同分子分型乳腺癌的效能，比较各模型曲线下面积（AUC）的差异。结果 测试组随机森林（RF）、极端梯度提升（XGBoost）、逻辑回归（LR）及支持向量机（SVC）模型判断不同分子分型乳腺癌的敏感度分别为74.10%、74.10%、77.80%和70.40%，特异度分别为63.60%、51.50%、57.60%和60.60%，准确率分别为68.30%、61.70%、66.70%和65.00%；其中RF模型判断Luminal型与非Luminal型乳腺癌的AUC值最大（AUC=0.70，P<0.05），但与其他模型间差异均无统计学意义（P均>0.05）。结论 RF模型预测不同分子分型乳腺癌的效能较好。     

基于临床、超声特征及影像组学构建机器学习模型预测慢性肾脏病患者肾功能损伤程度

目的 观察基于临床、超声特征及影像组学构建机器学习(ML)模型预测慢性肾脏病(CKD)患者肾功能损伤程度的价值。方法 回顾性分析199例CKD患者资料,以9 ∶ 1比例将其分为训练集(n=179)及验证集(n=20),根据估算肾小球滤过率(eGFR)划分轻中度或重度肾功能损伤。采用多因素logistic回归分析训练集临床及超声特征,筛选CKD患者肾功能损伤程度的独立预测因素,分别基于支持向量机(SVM)、极致梯度提升(XGBoost)及逻辑回归(LR)算法构建临床-超声模型、影像组学模型及联合模型;绘制受试者工作特征(ROC)曲线,计算曲线下面积(AUC),评估各模型预测CKD患者肾功能损伤程度的效能。结果 肾脏长径为CKD患者肾功能损伤的独立预测因素(P＜0.05)。以不同算法所获模型中,以SVM算法所获临床-超声模型、影像组学模型及联合模型预测肾功能损伤的效能最高;训练集中,以SVM算法所获临床-超声模型的敏感度、特异度、准确率及AUC分别为81.93%,62.50%,71.51%及0.722,影像组学模型分别为89.16%,70.83%,79.33%及0.800,联合模型分别为84.34%,80.21%,82.12%及0.822;验证集中,以SVM算法所获临床-超声模型的敏感度、特异度、准确率及AUC分别为75.00%、66.67%、70.00%及0.708,影像组学模型分别为75.00%、58.33%、65.00%及0.667,联合模型分别为87.50%、75.00%、80.00%及0.812。结论 基于超声特征联合影像组学构建的ML模型可有效预测CKD患者肾功能损伤程度;利用SVM算法获得的联合模型具有最佳效能。     

基于一站式全脑CT灌注动态列线图预测动脉瘤性蛛网膜下腔出血后迟发性脑缺血

目的 观察基于一站式全脑CT灌注(CTP)动态列线图预测动脉瘤性蛛网膜下腔出血(aSAH)后迟发性脑缺血(DCI)的价值。方法 前瞻性对233例aSAH患者行一站式全脑CTP检查。按7[DK(]∶[DK)]3比例随机将其分为训练集(n=164)和验证集(n=69)并于集内根据是否发生DCI划分亚组;采用单因素分析、线性诊断和多因素logistic回归分析筛选预测aSAH后DCI的独立因素,建立传统列线图,生成基于网络的动态列线图;绘制受试者工作特征(ROC)曲线,评估动态列线图预测aSAH后DCI的效能。结果 高血压×平均流入时间(mTTS)、世界神经外科医师联盟(WFNS)分级、改良Fisher分级(mFS)及平均流量提取乘积(mFEP)均为aSAH后DCI的独立预测因素。基于此构建的动态列线图预测训练集aSAH后DCI的敏感度、特异度及曲线下面积(AUC)分别为70.00%、89.50%及0.890,在验证集分别为76.20%、83.33%及0.870。结论 基于一站式全脑CTP动态列线图可有效预测aSAH后DCI。     

比较MR弹性成像及动态增强成像评价肝硬化食管胃底静脉曲张

目的 比较MR弹性成像（MRE）及动态增强成像（DCE-MRI）诊断肝硬化食管胃底静脉曲张（GEV）的价值。方法 收集接受MRE及DCE-MRI检查的肝硬化患者59例,记录血小板计数（PLT）,测量肝弹性值（HS）、脾弹性值（SS）和MR增强视觉分级相关指标;以内镜结果为金标准,采用ROC曲线下面积（AUC）比较相关指标诊断GEV的价值。结果 PLT、HS、SS及MR增强视觉分级与肝硬化GEV分级具有相关性（r_s=-0.317、0.436、0.682、0.703,P均<0.05）。诊断有无GEV时,SS的AUC略高于MR增强视觉分级、HS、PLT （AUC分别为0.880、0.795、0.744、0.635）,其中SS与PLT的AUC差异有统计学意义（P=0.002）;诊断中重度GEV时,MR增强视觉分级的AUC略高于SS、HS、PLT （AUC分别为0.893、0.816、0.713、0.665）,其中MR增强视觉分级与HS、PLT的AUC差异有统计学意义（P=0.018、0.002）。联合SS及MR增强视觉分级,鉴别诊断有无GEV及中重度GEV的敏感度分别为94.16%、96.83%。结论 MRE可有效预测GEV及其严重程度,与DCE-MRI效果相当。     

基于剪切波弹性成像和卷积神经网络建立深度学习模型预测肾脏病变

目的 基于剪切波弹性成像（SWE）量化参数和卷积神经网络建立深度学习（DL）模型预测肾脏病变。方法 采集94例肾脏病变患者（病例组）和109名健康人（对照组）的肾脏超声SWE量化参数。利用卷积神经网络建立DL模型,比较DL模型和支持向量机、随机森林模型预测肾脏病变的敏感度、特异度、准确率和曲线下面积（AUC）。结果 DL模型对预测肾脏病变的敏感度为90.48%,特异度为100%,准确率为95.12%,AUC为0.93;支持向量机模型的敏感度、特异度、准确率和AUC分别为80.74%、80.71%、80.98%、0.90,随机森林模型分别为82.22%、77.87%、80.33%和0.88。DL模型预测敏感度、特异度、准确率和AUC均高于支持向量机和随机森林模型,与支持向量机模型和随机森林模型预测肾脏病变差异均有统计学意义（P均<0.05）。结论 基于SWE量化参数和卷积神经网络的DL模型预测肾脏疾病性能良好,具有一定临床价值。     

弥散加权成像直方图参数模型预测高级别胶质瘤复发时间

目的 评估弥散加权成像（DWI）直方图参数预测模型对预测高级别胶质瘤（HGG）复发时间（TTR）的价值。方法 收集39例经手术病理确诊并术后复发HGG患者,根据TTR分为短期组（TTR≤6个月,n=17）及长期组（TTR>6个月,n=22）;回顾分析术前头部DWI,提取病灶的直方图参数,包括均值（mean）、方差（variance）、偏度（skewness）、峰度（kurtosis）和第1、10、50、90、99百分位数（pere.1%、pere.10%、pere.50%、pere.90%、pere.99%）,观察病灶囊变直径是否>30 mm、瘤周水肿、边界清晰与否及有无花环样强化,比较上述参数组间差异。分别基于直方图参数和联合病灶形态特征建立预测HGG的TTR逻辑回归（LR）预测模型及联合预测模型,以受试者工作特征（ROC）曲线评估其诊断效能。结果 长期组囊变直径大于短期组（P<0.05）;variance、skewness、pere.50%值均低于短期组（P均<0.05）。variance预测HGG TTR的效能最高,其诊断敏感度、特异度、准确率及曲线下面积（AUC）分别为70.60%、72.70%、71.80%及0.78。LR预测模型预测HGG TTR的敏感度、特异度、准确率及AUC分别为76.40%、68.20%、71.80%、0.80,联合预测模型分别为76.40%、77.30%、76.90%、0.82。结论 基于DWI直方图参数的LR预测模型对预测HGG的TTR具有一定价值;联合病灶形态特征有助于提高预测准确率。     

血清钠离子浓度联合红细胞比容对急性心力衰竭短期预后的预测价值

目的： 探讨低钠血症联合红细胞比容与急性心力衰竭（心衰）患者短期预后的关系。方法： 选择2019年1月至2020年7月锦州医科大学阜新市中心医院收治的因急性心衰入院患者498例，记录患者临床情况、基础疾病、心脏彩色多普勒超声（彩超）指标以及入院24 h内化验指标。按照血清钠离子浓度将急性心衰患者分为血钠正常组（血清钠浓度≥135 mmol/L）和低钠血症组（血清钠浓度<135 mmol/L）。按照红细胞比容将低钠血症组分为稀释性低钠血症亚组（红细胞比容：男性<40%，女性<37%）和消耗性低钠血症亚组（红细胞比容：男性≥40%，女性≥37%）。比较各组患者住院期间死亡率，以及出院后30 d、90 d内死亡及再入院情况，分析血清钠离子浓度联合红细胞比容对患者出院短期预后的预测价值。结果： 498例患者中，低钠血症患者86例，稀释性低钠血症34例，消耗性低钠血症52例。观察期间出现不良事件167例，稀释性低钠血症23例，消耗性低钠血症22例，血钠正常122例。调整基线特征后，稀释性低钠血症是急性心衰患者出院30 d和90 d不良事件的独立危险因素（P<0.05）。血清钠离子浓度、HCT及两者联合预测急性心衰患者短期预后的AUC分别为0.734、0.657、0.762（P<0.001）。结论： 稀释性低钠血症是急性心衰患者短期预后的独立预测因子，预测价值较高。     

CT预测急性肠系膜缺血继发性肠坏死

目的 评估CT预测急性肠系膜缺血(AMI)继发性肠坏死的价值。方法 回顾性分析78例经手术病理证实AMI患者的腹部CT资料,根据是否发生继发性肠坏死将其分为肠坏死组(n=26)及无肠坏死组(n=52)。采用单因素分析和多因素logistic回归分析筛选CT预测AMI继发性肠坏死的独立因素,并建立联合模型,绘制受试者工作特征(ROC)曲线,评估其单一CT参数及联合模型预测AMI继发性肠坏死的效能,计算其曲线下面积(AUC)。结果 组间血管狭窄或闭塞、肠壁积气、肠系膜静脉积气、"缆绳征"及肠壁异常强化差异均有统计学意义(P均＜0.05)。CT所示肠系膜血管3级及以下分支狭窄或闭塞、肠壁积气和肠系膜静脉积气为预测AMI继发性肠坏死的独立预测因素(P均＜0.05);其预测AMI继发性肠坏死的AUC分别为0.66、0.73及0.72,联合模型的AUC为0.89。结论 CT对于预测AMI继发性肠坏死具有一定临床应用价值。     

超声监测膈肌厚度吸气变化率对机械通气患者拔管结局评价

目的 评估超声检测膈肌增厚率对预测机械通气（MV）患者拔管结局的价值。方法 选取重症医学科（ICU）行MV>48 h且准备拔管的54例患者，于自主呼吸试验（SBT）期间以床旁超声测量并计算膈肌增厚率（DTF）和膈肌增厚浅快呼吸指数（DTF-RSBI），同时记录浅快呼吸指数（RSBI）及其他生理指标。采用ROC曲线评价DTF和DTF-RSBI预测拔管成败的价值。结果 36例拔管成功（成功组），18例失败（失败组），成功组患者DTF明显高于失败组，RBSI及DTF-RBSI明显低于失败组（P均<0.05）。取28.50%为截断值，DTF预测拔管的AUC为0.702，敏感度和特异度分别为78.80%和61.10%；DTF-RBSI取72.6次/（min·mm）为截断值，预测拔管的AUC为0.903，敏感度和特异度分别为100.00%和72.20%。结论 DTF-RSBI预测拔管结果比DTF及传统RSBI更准确，具有较高实用价值。     

Use of antidementia drugs and risk of pneumonia in older persons with Alzheimer’s disease

Introduction: Persons with Alzheimer’s disease are at an increased risk of pneumonia, but the comparative risks during specific antidementia treatments are not known. We compared the risk of pneumonia in the use of donepezil, rivastigmine (oral, transdermal), galantamine and memantine.

Patients and methods: We used data from a nationwide cohort of community-dwelling individuals diagnosed with Alzheimer’s disease during 2005–2011 in Finland, who initiated monotherapy with acetylcholinesterase inhibitor or memantine (n?=?65,481). The risk of hospitalization or death due to pneumonia was investigated with Cox proportional hazard models.

Results: The risk of pneumonia was higher in persons using rivastigmine patch (n?=?9709) (adjusted hazard ratio (HR) 1.15, 95% confidence interval (CI) 1.04–1.27) and memantine (n?=?11,024) (HR 1.59, 95% CI 1.48–1.71) compared with donepezil users (n?=?26,416) whereas oral rivastigmine (n?=?7384) (HR 1.08, 95% CI 0.98–1.19) and galantamine (n?=?10,948) (HR 0.91, 95% CI 0.83–1.00) were not associated with an increased risk. These results did not change when adjusting for comorbid conditions, use of psychotropic drugs or with inverse probability of treatment weighting.

Discussion: The increased risk of pneumonia in this fragile group of aged persons should be taken into account. Memantine is associated with the highest risk in the comparison of antidementia drugs.

• KEY Message

• Pneumonia risk is increased in persons with Alzheimer’s disease who use memantine or rivastigmine patches.

     

Risk factors for ventilator-associated pneumonia in trauma patients with torso injury: a retrospective single-center study

ObjectiveWe aimed to identify the risk factors for ventilator-associated pneumonia in patients admitted to critical care after a torso injury.MethodsWe retrospectively evaluated 178 patients with torso injury aged >15 years who were intubated in the emergency room and placed on a mechanical ventilator after intensive care unit (ICU) admission, survived for >48 hours, had thoracic and/or abdominal injuries, and had no end-stage renal disease. We compared clinico-laboratory variables between ventilator-associated pneumonia (n = 54, 30.3%) and non-ventilator-associated pneumonia (n = 124, 69.7%) groups. Risk factors for ventilator-associated pneumonia were assessed using multivariable logistic regression analysis.ResultsVentilator-associated pneumonia was associated with a significantly longer stay in the ICU (11.3 vs. 6.8 days) and longer duration of mechanical ventilation (7 vs. 3 days). Injury Severity Score (adjusted odds ratio [AOR]: 1.048; 95% confidence interval [CI]: 1.008–1.090), use of vasopressors (AOR: 2.541; 95% CI: 1.121–5.758), and insertion of a nasogastric tube (AOR: 6.749; 95% CI: 2.397–18.999) were identified as independent risk factors of ventilator-associated pneumonia.ConclusionVentilator-associated pneumonia in patients with torso injury who were admitted to the ICU was highly correlated with Injury Severity Score, use of vasopressors, and insertion of a nasogastric tube.     

A novel prognostic model for angioimmunoblastic T-cell lymphoma: A retrospective study of 55 cases

ObjectiveTo explore prognostic factors and develop an accurate prognostic prediction model for angioimmunoblastic T-cell lymphoma (AITL).MethodsClinical data from Chinese patients with newly diagnosed AITL were retrospectively analysed. Overall survival (OS) and progression-free survival (PFS) were estimated using Kaplan-Meier method survival curves; prognostic factors were determined using a Cox proportional hazards model. The sensitivity and specificity of the predicted survival rates were compared using area under the curve (AUC) of receiver operating characteristic (ROC) curves.ResultsThe estimated 5-year OS and PFS of 55 eligible patients with AITL were 22% and 3%, respectively. Multivariate analysis showed that the presence of pneumonia, and serous cavity effusions at initial diagnosis were significant prognostic factors for OS. Based on AUC ROC values, our novel prognostic model was superior to IPI and PIT based models and suggested better diagnostic accuracy.ConclusionsOur prognostic model based on pneumonia, and serous cavity effusions at initial diagnosis enabled a balanced classification of AITL patients into different risk groups.     

Risk factors of bacteremia in children hospitalized with community-acquired pneumonia: A nested case-control study

ObjectiveTo assess the risk factors of bacteremia in children hospitalized with community-acquired pneumonia (CAP).Study designThe present, nested, case-control study enrolled a cohort of patients with CAP aged < 18 years who were hospitalized at Tokyo Metropolitan Children’s Medical Center or Tama-Hokubu Medical Center between March 2010 and February 2018. Among the cohort with blood cultures (BCs), patients with bacteremia were identified and matched with five control patients based on their treatment facility, underlying disease, and age. Conditional logistic regression was used to calculate the odds ratios (ORs) of bacteremia for risk factor candidates.ResultsBCs were obtained for 2,383 (84%) of the 2,853 patients in the CAP cohort. Of those with BCs, 34 (1.4%) had bacteremia. S. pneumoniae and H. influenzae accounted for 26 (76%) and four (12%) instances of the bacteremia pathogens, respectively. Bacteremia occurred more frequently among patients hospitalized in the spring than during other seasons (P = 0.022). On multivariate analysis, the severity of pneumonia was not associated with bacteremia incidence (OR: 0.92 [0.30–2.85]) while a white blood cell count > 16,000/μL (OR: 5.90 [2.14–16.3]) was shown to be a significant risk factor. The OR of the need for a ventilator on admission day was significantly high (28.4 [3.02–1374]) on univariate analysis, but the subject pool was too small to determine its significance on multivariate analysis.ConclusionsThe results of the present study supported BC collection in patients with leukocytosis and in those requiring ventilator use on admission.     

Proton pump inhibitors versus histamine-2 receptor blockers for stress ulcer prophylaxis in patients with sepsis: a retrospective cohort study

ObjectiveWe aimed to compare the efficacy and risks of proton pump inhibitor (PPI) versus histamine-2 receptor blocker (H2B) use for stress ulcer prophylaxis (SUP) in critically ill patients with sepsis and risk factors for gastrointestinal bleeding (GIB).MethodsIn this retrospective cohort study, we used the Medical Information Mart for Intensive Care III Clinical Database to identify critically ill adult patients with sepsis who had at least one risk factor for GIB and received either an H2B or PPI for ≥48 hours. Propensity score matching (PSM) was conducted to balance baseline characteristics. The primary outcome was in-hospital mortality.ResultsAfter 1:1 PSM, 1056 patients were included in the H2B and PPI groups. The PPI group had higher in-hospital mortality (23.8% vs. 17.5%), GIB (8.9% vs. 1.6%), and pneumonia (49.6% vs. 41.6%) rates than the H2B group. After adjusting for risk factors of GIB and pneumonia, PPI use was associated with a 1.28-times increased risk of in-hospital mortality, 5.89-times increased risk of GIB, and 1.32-times increased risk of pneumonia.ConclusionsAmong critically ill adult patients with sepsis at risk for GIB, SUP with PPIs was associated with higher in-hospital mortality and higher risk of GIB and pneumonia than H2Bs.     

Development and Validation of a Risk Calculator for Predicting Postoperative Pneumonia

ObjectiveTo identify preoperative factors associated with an increased risk of postoperative pneumonia and subsequently develop and validate a risk calculator.Patients and MethodsThe American College of Surgeons’ National Surgical Quality Improvement Program, a multicenter, prospective data set (2007-2008) was used. Univariate and multivariate logistic regression analyses were performed. The 2007 data set (N=211,410) served as the training set, and the 2008 data set (N=257,385) served as the validation set.ResultsIn the training set, 3825 patients (1.8%) experienced postoperative pneumonia. Patients who experienced postoperative pneumonia had a significantly higher 30-day mortality (17.0% vs 1.5%; P<.001). On multivariate logistic regression analysis, 7 preoperative predictors of postoperative pneumonia were identified: age, American Society of Anesthesiologists class, chronic obstructive pulmonary disease, dependent functional status, preoperative sepsis, smoking before operation, and type of operation. The risk model based on the training data set was subsequently validated on the validation data set, with model performance being very similar (C statistic: 0.860 and 0.855, respectively). The high C statistic indicates excellent predictive performance. The risk model was used to develop an interactive risk calculator.ConclusionPreoperative variables associated with an increased risk of postoperative pneumonia include age, American Society of Anesthesiologists class, chronic obstructive pulmonary disease, dependent functional status, preoperative sepsis, smoking before operation, and type of operation. The validated risk calculator provides a risk estimate for postoperative pneumonia and is anticipated to aid in surgical decision making and informed patient consent.     

Nomogram prediction of caries risk among schoolchildren age 7 years based on a cohort study in Shanghai

ObjectiveCaries risk assessment tools are essential for identifying and providing treatment for individuals at high risk of developing caries. We aimed to develop a nomogram for the assessment and evaluation of caries risk among Chinese children.MethodsWe enrolled schoolchildren age 7 years from a primary school in Shanghai. Baseline information of participants was collected using a questionnaire completed by children’s caregivers. A nomogram of a novel prediction scoring model was established based on predictors detected in univariate and multivariate analyses. Predictive accuracy and discriminative ability of the nomogram were calculated using the concordance index (C index). The bootstrap method (1000 samples) was used to decrease overfitting. The net benefit of the model was validated using decision curve analysis.ResultsOverall, 406 children with complete information and two completed dental examinations were included in the final analysis. The nomogram based on logistic regression model coefficients demonstrated a C index of 0.766 (95% confidence interval: 0.761–0.771) for caries risk. The net benefit of the decision curve analysis was 38.6% at 55% threshold probability.ConclusionThis nomogram model, derived using dietary habits, oral hygiene status, and caries experience, showed promising predictive ability to assess the caries risk among Chinese children.     

Cefepime vs. meropenem for moderate-to-severe pneumonia in patients at risk for aspiration: An open-label,randomized study

BackgroundTreatment of aspiration pneumonia is an important problem due to aging of populations worldwide. However, the effectiveness of cefepime in aspiration pneumonia has not yet been evaluated.AimTo compare the clinical efficacy and safety of cefepime and meropenem in patients with moderate-to-severe aspiration pneumonia.MethodsIn this open-label, randomized study, either cefepime 1 g or meropenem 0.5 g was administered intravenously every 8 h to patients with moderate-to-severe community-acquired or nursing-home acquired pneumonia at risk for aspiration for an average of 10.5 days. The primary outcome was the clinical response rate at the end of treatment (EOT) in the validated per-protocol (VPP)-population. Secondary outcomes were clinical response during treatment (days 4 and 7) and at the end of study (EOS) in the VPP-population, and survival at day 30 in the modified intention-to-treat (MITT)-population.ResultsThere was no difference between the groups in the primary or secondary outcomes or safety. Significant improvement was observed in each group on day 4.ConclusionCefepime is as effective and safe as meropenem in the treatment of moderate-to-severe aspiration pneumonia.Clinical trials identifierUMIN000001349.     

Definitions,rates and associated mortality of ICU-acquired pneumonia: A multicenter cohort study

IntroductionWe aimed to analyze intensive care unit (ICU)-acquired pneumonia according to 7 definitions, estimating associated hospital mortality.MethodsThis cohort study was nested within an international randomized trial, evaluating the effect of probiotics on ICU-acquired pneumonia in 2650 mechanically ventilated adults. Each clinically suspected pneumonia was adjudicated by two physicians blinded to allocation and center. The primary outcome was ventilator-associated pneumonia (VAP) informed by ventilation for ≥2 days, new, progressive or persistent infiltrate plus 2 of: temperature > 38 °C or < 36 °C; leukopenia (<3 × 10(Fernando et al., 2020⁶⁾/L) or leukocytosis (>10 × 10(Fernando et al., 2020⁶⁾/L); and purulent sputum. We also used 6 other definitions estimating the risk of hospital mortality.ResultsThe frequency of ICU-acquired pneumonia varied by definition: the trial primary outcome VAP (21.6%), Clinical Pulmonary Infection Score (CPIS) (24.9%), American College Chest Physicians (ACCP) (25.0%), International Sepsis Forum (ISF) (24.4%), Reducing Oxidative Stress Study (REDOXS) (17.6%), Centers for Disease Control (CDC) (7.8%), and invasively microbiologically confirmed (1.9%). The trial primary outcome VAP (HR 1.31 [1.08, 1.60]), ISF (HR 1.32 [1.09,1.60]), CPIS (HR 1.30 [1.08,1.58]) and ACCP definitions (HR 1.22 [1.00,1.47]) were associated with hospital mortality.ConclusionsRates of ICU-acquired pneumonia vary by definition and are associated with differential increased risk of death.     

Risk factors associated with methicillin-resistant Staphylococcus aureus isolation from serially collected sputum samples of patients hospitalized with pneumonia

IntroductionRisk factors associated with the new detection of methicillin-resistant Staphylococcus aureus (MRSA) during hospitalization remain unclear. This study aimed to identify risk factors associated with MRSA isolation from the sputum of patients admitted with pneumonia, during their hospitalization.MethodsPatients were prospectively enrolled from 2003 to 2012. Sputum samples were collected for bacterial cultures on days 1, 4, 7, 11, and 14 of hospitalization and thereafter. Cases of MRSA first isolated from sputum obtained before day 4 were defined as “carriage on admission.” Cases of MRSA first isolated on day 4 and thereafter, were defined as “new detection after admission.” Statistical analysis was used to investigate the risk factors associated with MRSA isolation.ResultsMRSA was isolated from 167 of 1,008 patients (carriage: 47; new detection: 120). Multivariate analysis revealed that the risk factors for MRSA carriage were activities of daily living (ADL) disability prior to admission (odds ratio [OR], 2.92; 95% confidence interval [CI], 1.37–6.22) and hospitalization within the previous 90 days (OR, 3.75; 95% CI, 1.90–7.41). ADL disability prior to admission (risk ratio [RR], 1.82; 95% CI, 1.17–2.84) and a high pneumonia severity index score upon admission (RR, 2.20; 95% CI, 1.37–3.65) were risk factors for new detection of MRSA.ConclusionsSeveral risk factors were found to be associated with MRSA carriage and/or its new detection, based on the sputum samples from patients admitted with pneumonia. These factors may be indicators for selective surveillance and the early implementation of infection control measures.