人工智能技术在肺部影像辅助诊断中的应用进展

肺部影像不仅表现复杂,而且数据量增长迅速,多种因素导致影像科医生任务繁重。人工智能辅助诊断技术的出现恰逢其时,当前的智能诊断算法能够实现肺部病灶检出、分割和性质判断等多种应用模式,不仅有效提升医生诊断的效率、更有望推动分级诊疗、优化医疗资源配置。基于人工智能的肺部影像诊断技术已经从单一特定的疾病诊断逐渐发展到多疾病联合诊断。本文综述人工智能辅助诊断技术的发展背景,分析基于人工智能的肺部疾病诊断的研究现状,最后总结相关算法的优缺点和未来的发展方向。     

Clinical,radiological, and laboratory characteristics and risk factors for severity and mortality of 289 hospitalized COVID-19 patients

Background

The coronavirus disease 2019 (COVID-19) has become a global pandemic, with 10%-20% of severe cases and over 508 000 deaths worldwide.

Objective

This study aims to address the risk factors associated with the severity of COVID-19 patients and the mortality of severe patients.

Methods

289 hospitalized laboratory-confirmed COVID-19 patients were included in this study. Electronic medical records, including patient demographics, clinical manifestation, comorbidities, laboratory tests results, and radiological materials, were collected and analyzed. According to the severity and outcomes of the patients, they were divided into three groups: nonsurvived (n = 49), survived severe (n = 78), and nonsevere (n = 162) groups. Clinical, laboratory, and radiological data were compared among these groups. Principal component analysis (PCA) was applied to reduce the dimensionality and visualize the patients on a low-dimensional space. Correlations between clinical, radiological, and laboratory parameters were investigated. Univariate and multivariate logistic regression methods were used to determine the risk factors associated with mortality in severe patients. Longitudinal changes of laboratory findings of survived severe cases and nonsurvived cases during hospital stay were also collected.

Results

Of the 289 patients, the median age was 57 years (range, 22-88) and 155 (53.4%) patients were male. As of the final follow-up date of this study, 240 (83.0%) patients were discharged from the hospital and 49 (17.0%) patients died. Elder age, underlying comorbidities, and increased laboratory variables, such as leukocyte count, neutrophil count, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), procalcitonin (PCT), D-dimer, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and blood urea nitrogen (BUN) on admission, were found in survived severe cases compared to nonsevere cases. According to the multivariate logistic regression analysis, elder age, a higher number of affected lobes, elevated CRP levels on admission, increased prevalence of chest tightness/dyspnea, and smoking history were independent risk factors for death of severe patients. A trajectory in PCA was observed from "nonsevere" toward "nonsurvived" via "severe and survived" patients. Strong correlations between the age of patients, the affected lobe numbers, and laboratory variables were identified. Dynamic changes of laboratory findings of survived severe cases and nonsurvived cases during hospital stay showed that continuing increase of leukocytes and neutrophil count, sustained lymphopenia and eosinopenia, progressing decrease in platelet count, as well as high levels of NLR, CRP, PCT, AST, BUN, and serum creatinine were associated with in-hospital death.

Conclusions

Survived severe and nonsurvived COVID-19 patients had distinct clinical and laboratory characteristics, which were separated by principle component analysis. Elder age, increased number of affected lobes, higher levels of serum CRP, chest tightness/dyspnea, and smoking history were risk factors for mortality of severe COVID-19 patients. Longitudinal changes of laboratory findings may be helpful in predicting disease progression and clinical outcome of severe patients.

     

Clinical characteristics of 3062 COVID-19 patients: A meta-analysis

We aimed to systematically review the clinical characteristics of coronavirus disease 2019 (COVID-19). Seven databases were searched to collect studies about the clinical characteristics of COVID-19 from January 1, 2020 to February 28, 2020. Then, meta-analysis was performed by using Stata12.0 software. A total of 38 studies involving 3062 COVID-19 patients were included. Meta-analysis showed that a higher proportion of infected patients was male (56.9%). The incidence rate of respiratory failure or acute respiratory distress syndrome was 19.5% and the fatality rate was 5.5%. Fever (80.4%), fatigue (46%), cough (63.1%), and expectoration (41.8%) were the most common clinical manifestations. Other common symptoms included muscle soreness (33%), anorexia (38.8%), chest tightness (35.7%), shortness of breath (35%), dyspnea (33.9%). Minor symptoms included nausea and vomiting (10.2%), diarrhea (12.9%), headache (15.4%), pharyngalgia (13.1%), shivering (10.9%), and abdominal pain (4.4%). The proportion of patients that was asymptomatic was 11.9%. Normal leukocyte counts (69.7%), lymphopenia (56.5%), elevated C-reactive protein levels (73.6%), elevated ESR (65.6%), and oxygenation index decreased (63.6%) were observed in most patients. About 37.2% of patients were found with elevated D-dimer, 25.9% of patients with leukopenia, along with abnormal levels of liver function (29%), and renal function (25.5%). Other findings included leukocytosis (12.6%) and elevated procalcitonin (17.5%). Only 25.8% of patients had lesions involving a single lung and 75.7% of patients had lesions involving bilateral lungs. The most commonly experienced symptoms of COVID-19 patients were fever, fatigue, cough, and expectoration. A relatively small percentage of patients were asymptomatic. Most patients showed normal leucocytes counts, lymphopenia, elevated levels of C-reactive protein and ESR. Bilateral lung involvement was common.     

Diagnostic value of SPECT, PET and PET/CT in the diagnosis of coronary artery disease: A systematic review

Purpose:

The purpose of the study was to investigate the diagnostic value of SPECT, PET and PET/CT in the diagnosis of coronary artery disease, based on a systematic review.

Material and Methods:

A search of PubMed/Medline and Sciencedirect databases in the English-language literature published over the last 24 years was performed. Only studies with at least 10 patients comparing SPECT, PET or combined PET/CT with invasive coronary angiography in the diagnosis of coronary artery disease (50% stenosis) were included for analysis. Sensitivities and specificities estimates pooled across studies were analysed using a Chi-square test.

Results:

Twenty-five studies met the selection criteria and were included for the analysis. Ten studies were performed with SPECT alone; while another six studies were performed with PET alone. Five studies were carried out with both PET and SPECT modalities, and the remaining four studies were investigated with integrated PET-CT. The mean value of sensitivity, specificity and accuracy of these imaging modalities for the diagnosis of coronary artery disease was 82% (95%CI: 76 to 88), 76% (95%CI: 70 to 82) and 83% (95%CI: 77 to 89) for SPECT; 91% (95%CI: 85 to 97), 89% (95%CI: 83 to 95) and 89% (95%CI: 83 to 95) for PET; and 85% (95%CI: 79 to 90), 83% (95%CI: 77 to 89) and 88% (95%CI: 82 to 94) for PET/CT, respectively. The diagnostic accuracy of these imaging modalities was dependent on the radiotracers used in these studies, with ammonia resulting in the highest diagnostic value.

Conclusion:

Our review shows that PET has high diagnostic value for diagnosing coronary artery disease, and this indicates that it is a valuable technique for both detection and prediction of coronary artery disease.     

Comparison of Luminex xTAG® RVP fast assay and real time RT‐PCR for the detection of respiratory viruses in adults with community‐acquired pneumonia

Community‐acquired pneumonia (CAP) is the third cause of death worldwide. Viruses are frequently detected in adult CAP. Highly sensitive diagnostic techniques should be used due to poor viral shedding. Different sampling methods can affect viral detection, being necessary to establish the optimal type of sample for identifying respiratory viruses in adults. The detection rates of respiratory viruses by Luminex xTAG® RVP fast assay, real time RT‐PCR (rtRT‐PCR) (Sacace®), and immunofluorescence assay (IFA) in adult CAP were performed in nasopharyngeal swabs (NPS) and aspirates (NPA) from 179 hospitalized adults. Positivity was 47.5% for Luminex®, 42.5% for rtRT‐PCR (P = 0.3), and 2.7% for IFA (2.7%) (P < 0.0). The sensitivity, specificity, and kappa coefficient of xTAG® RVP compared with rtRT‐PCR were 84.2%, 79.6%, and 0.62%, respectively. Luminex® and rtRT‐PCR detected 65 (58.0%) and 57 (50.9%) viruses in 112 NPA and 35 (34.3%) and 31 (30.4%) in 102 NPS, respectively (P < 0.01). xTAG® RVP is appropriate for detecting respiratory viruses in CAP adults. Both molecular techniques yielded better results with nasopharyngeal aspirate than swabs. J. Med. Virol. 88:1173–1179, 2016 . © 2016 Wiley Periodicals, Inc.

     

Studies on viral pneumonia related to novel coronavirus SARS-CoV-2, SARS-CoV,and MERS-CoV: a literature review

Coronaviruses are a class of RNA viruses that can cause respiratory and intestinal infections in animals and humans. SARS-CoV, MERS-CoV, and a novel coronavirus (SARS-CoV-2 [2019-nCoV]) belong to the family Coronaviridae and the genus Betacoronavirus. At present, the understanding of SARS-CoV-2 is getting deeper and deeper. In order to better prevent and treat SARS-CoV-2, this article compares the infectivity, pathogenicity, and related clinical characteristics of the three human pathogenic coronaviruses, SARS-CoV-2, SARS-CoV, and MERS-CoV to help us further understand the pathogenic characteristics of novel coronaviruses.     

Acute respiratory distress syndrome in adenovirus type 4 pneumonia: A case report

Human adenoviruses (HAdVs) cause a wide spectrum of clinical syndromes, depending on species and types, from mild respiratory infections to deadly pneumonia: in particular, severe infections occur in immunocompromised patients. In this report, we describe the case of a 36 years-old woman admitted to our intensive care unit (ICU) with severe respiratory distress syndrome caused by adenovirus pneumonia, that required invasive respiratory support (mechanical ventilation and extracorporeal membrane oxygenation). Molecular assays detected the virus in respiratory and plasma specimen and sequencing procedure identified HAdV type 4. Patient improved after cidofovir administration. Leukopenia and subsequent bacterial infection occurred, but the patient recovered completely and was discharged from the hospital after 54 days.     

Asp57-negative HLA DQ beta chain and DQA1*0501 allele are essential for the onset of DQw2-positive and DQw2-negative coeliac disease.

The genetic predisposition to coeliac disease is associated with the HLA DQw2 allele. Coeliac patients lacking the DQw2 allele are very rare and always exhibit the DR4-DQw3 haplotype. We performed oligotyping of polymerase chain reaction (PCR)-amplified DQA1 and DQB1 genes in six DQw2-negative and 30 DQw2-positive coeliac patients. The DQB analysis showed that all six DQw2-negative patients possessed the DQB1*0302 allele. The other DQB alleles found in five of these patients were DQB1*0501, DQB1*0604 and DQB1*0302. The DQ beta chains encoded from all these alleles have the replacement of aspartic acid residue at position 57 (Asp57), as well as the DQB1*0201 allele which was found in all 30 DQw2-positive coeliac patients. The DQw2-negative proband who lacked the homozygous Asp57 replacement exhibited the DQA1*0501 allele in the DQA1 gene. The DQA1*0501 allele was also found in 27 of the 30 DQw2-positive coeliac patients. Among this group of coeliacs, the four cases lacking the DQA1*0501 allele exhibited the homozygous Asp57 replacement in the DQ beta chain. Our results indicate that Asp57-negative DQ beta alleles are involved in both DQw2-positive and -negative coeliac patients. Moreover, when the Asp57-negative DQ beta chain is encoded from only one of the two DQB1 genes the DQA1*0501 allele is always present.     

Efficacy and safety of tixagevimab-cilgavimab as pre-exposure prophylaxis for COVID-19: A systematic review and meta-analysis

Some proportions of populations, such as immunocompromised patients and organ transplant recipients might have inadequate immune responses to the vaccine for coronavirus disease 2019 (COVID-19). For these groups of populations, administering monoclonal antibodies might offer some additional protection. This review sought to analyze the effectiveness and safety of tixagevimab-cilgavimab (Evusheld) as pre-exposure prophylaxis against COVID-19. We used specific keywords to comprehensively search for potential studies on PubMed, Scopus, Europe PMC, and ClinicalTrials.gov sources until 3 September 2022. We collected all published articles that analyzed tixagevimab-cilgavimab on the course of COVID-19. Review Manager 5.4 was utilized for statistical analysis. Six studies were included. Our pooled analysis revealed that tixagevimab-cilgavimab prophylaxis may decrease the rate of SARS-CoV-2 infection (OR: 0.24; 95% CI: 0.15–0.40, p < 0.00001, I² = 75%), lower COVID-19 hospitalization rate (OR: 0.13; 95% CI: 0.07–0.24, p < 0.00001, I² = 0%), decrease the severity risk (OR: 0.13; 95% CI: 0.07–0.24, p < 0.00001, I² = 0%), and lower COVID-19 deaths (OR: 0.17; 95% CI: 0.03–0.99, p = 0.05, I² = 72%). In the included studies, no major adverse events were reported. This study proposes that tixagevimab-cilgavimab was effective and safe for preventing COVID-19. Tixagevimab-cilgavimab may be offered to those who cannot be vaccinated or have inadequate immune response from the COVID-19 vaccine to give additional protection.     

多层螺旋CT在周围型肺癌和局灶性机化性肺炎鉴别诊断中的价值

目的:探讨多层螺旋CT(multi-slice spiral CT,MSCT)在周围型肺癌(peripheral lung cancer,PLC)和局灶性机化性肺炎(focal organizing pneumonia,FOP)诊断中价值.方法:搜集PLC患者78例(PLC组)和FOP患者35例(FOP组)的CT检查资料和临床资料,对比分析两组CT平扫和增强影像特点.结果:PLC组外带分布率低于FOP组(44.87%vs.80.00%),内带分布率高于FOP组(24.36%vs.0),差异均有统计学意义(P<0.05);PLC组大病灶空洞(25.71%vs.73.68%)、紧贴胸膜(22.86%vs.84.21%)与FOP组相比差异有统计学意义(P<0.05);两组在血管集束征(大病灶80.00%vs.36.84%,小病灶72.09%vs.31.25%)、毛刺、支气管充气征(大病灶31.43%vs.78.95%,小病灶30.23%vs.75.00%)、结构疏松(大病灶5.71%vs.47.37%,小病灶4.65%vs.43.75%)、胸膜凹陷(大病灶0 vs.52.63%,小病灶20.93%vs.81.25%)方面差异有统计学意义(P<0.05),其余各个征象组间比较差异均无统计学意义(P>0.05);两组均进行动脉期、静脉期增强扫描,PLC组动脉期净增CT值[大病灶(18.61±9.55)Hu vs.(29.60±12.35)Hu;小病灶(19.34±9.06)Hu vs.(28.72±11.09)Hu]和总增加CT值[大病灶(32.76±10.91)Hu vs.(44.53±12.29)Hu;小病灶(29.45±10.70)Hu vs.(41.10±11.89)Hu]均低于FOP组,差异有统计学意义(P<0.01).结论:PLC和FOP的CT征象有一定特征性和差异性,MSCT可清晰显示出上述特征性和差异性,在两种病灶的鉴别诊断中具有重要作用.     

Detection of α-thalassemia-1 (Southeast Asian type) and its application for prenatal diagnosis

A simple non-radioactive method based on the polymerase chain reaction was used to detect the Southeast Asian type of α-thalassemia 1 (–). Three oligonucleotide primers, one of which was adjacent to the breakpoint of the α-thalassemia-1 allele, were used to amplify the 570 and 194 bp DNA fragments. The 570 bp product was specific to the α-thalassemia-1 determinant and the 194 bp fragment was amplified from either the α-thalassemia-2 (-α) or normal α-globin (αα) determinants. In Hb Bart's hydrops fetalis (–/–), only the 570 bp fragment was obtained, whereas the 194 bp fragment was amplified in normal individual (αα/αα) and α-thalassemia-2 trait (-α/αα). Both 570 and 194 bp fragments were detected in α-thalassemia-1 trait (–/αα) and Hb H patients (–/-α). This procedure is useful for the rapid screening of α-thalassemia-1 trait and prenatal diagnosis of Hb Bart's hydrops fetalis in populations with a high frequency of the Southeast Asian Type of α-thalassemia-1.     

parkin基因的一个新的点突变

目的：研究parkin基因外显子2-10点突变与散发性早发帕金森病发病的关系。方法：应用聚合酶链反应（polymerase chain reaction ，PCR）、琼脂糖电泳、单链构象多态性（single strand conformation polymorphism，SSCP）、DNA测序及限制性核酸内切酶酶切方法，检测了60例散发性早发帕金森病患者以及120名正常人外周血白细胞DNA的parkin基因外显子2-10点突变。结果：发现1例患者的parkin基因外显子2存在纯合突变（G237→C），限制性内切酶酶切证实，其它外显子未见突变，120名正常对照也未见突变。结论：parkin基因外显子存在点突变，可能与部分散发性早发帕金森病发病有关。     

Value of anal swabs for SARS-COV-2 detection: a literature review

Facing the unprecedented global public health crisis caused by coronavirus disease 2019 (COVID-19), nucleic acid tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are the gold standard for diagnosing COVID-19. The asymptomatic carriers were not suspected of playing a significant role in the ongoing pandemic, and universal nucleic acid screening in close contacts of confirmed cases and asymptomatic carriers has been carried out in many medium- and high-risk areas for the spread of the virus. Recently, anal swabs for key population screening have been shown to not only reduce missed diagnoses but also facilitate the traceability of infectious sources. As a specimen for the detection of viruses, the goal of this paper is to briefly review the transmission route of SARS-CoV-2 and the necessity of using anal swabs for SARS-CoV-2 screening to minimize transmission and a threat to other people with COVID-19.     

假肥大型肌营养不良症家系的基因检测与产前诊断

目的 分析假肥大型肌营养不良症(Duchenne and Becker muscular dystrophy,DMD/BMD)家系的致病突变,对胎儿进行产前诊断,并确定家系中的女性成员是否为突变携带者.方法 收集43个DMD/BMD家系,用多重PCR方法分析DMD基因缺失热点区的18个外显子;用多重连接依赖性探针扩增(multiplex ligation-dependent probe amplification,MLPA)方法对43例患者及32个家系中的36位女性进行DMD基因全部79个外显子的定量检测,为其中27个家系提供产前诊断.结果 用多重PCR共检测到26例缺失突变.采用MLPA方法,除多重PCR检测到的突变外,还检测到3例缺失和6例重复突变,突变范围明确.用MLPA检测的36例女性中,32例为患儿母亲,共发现16例突变携带者,另有2名女性亲属也被确诊为携带者.10名女性排除了携带者的可能性,8例不能确定.经产前诊断,18例男性胎儿中3例为患者,9例女性胎儿中1例为携带者.结论 MLPA方法可全面检测DMD基因缺失及重复突变,同时明确女性携带者,从而为产前诊断提供准确信息.