Search

BACKGROUND: At present, studies on MircoRNA-22-3p (miR-22-3p) in lung adenocarcinoma use a single method, lack multi-center validation and multi-method validation, and there is no big data concept to predict and validate target genes. OBJECTIVE: To investigate the expression, potential targets and clinicopathological significance of miR-22-3p in lung adenocarcinoma (LUAD) tissues. METHODS: LUAD formalin-fixed paraffin-embedded (FFPE) tumors and adjacent normal lung tissues were collected for real-time quantitative polymerase chain reaction (RT-qPCR); Collect miR-22-3p in LUAD and non-cancer lung tissue from high-throughput datasets, standardized mean difference (SMD) and area under the curve (AUC) of the comprehensive receiver operating curve (summary receiver operating characteristic cure, sROC cure) were calculated; Cell function experiments on A549 cells transfected with LV-hsa-miR-22; Target genes were predicted by the miRwalk2.0 website and the resulting target genes were subjected to Gene Ontology (GO) pathway enrichment analysis and constructed to protein-protein interaction network; Finally, the protein expression level of the key gene TP53 was validated by searching The Human Protein Atlas (THPA) database to incorporate TP53 immunohistochemical results in LUAD. RESULTS: RT-qPCR result from 41 pairs of LUAD and adjacent lung tissues showed that miR-22-3p was downregulated in LUAD (AUC = 0.6597, p= 0.0128); Globally, a total of 838 LUADs and 494 non-cancerous lung tissues were included, and were finally combined into 14 platforms. Compared with noncancerous tissue, miR-22-3p expression level was significantly reduced in LUAD tissue (SMD =-0.32, AUC = 0.72l); cell function experiments showed that miR-22-3p has inhibitory effects on cell proliferation, migration and invasion, and has promotion effect on apoptosis; Moreover, target genes prediction, GO pathway enrichment analysis and PPI network exhibited TP53 as a key gene of target gene of miR-22-3p; at last, a total of 114 high-throughput datasets were included, including 3897 LUADs and 2993 non-cancerous lung tissues, and were finally combined into 37 platforms. Compared with noncancerous tissue, TP53 expression level was significantly increased in LUAD (SMD = 0.39, p< 0.01) and it was verified by the protein expression data from THPA. CONCLUSION: Overexpression of miR-22-3p may inhibit LUAD cell proliferation, migration and invasion through TP53, and promote cell apoptosis.

The role of HOXA family genes in the occurrence and progression of a variety of human cancers has been scatteredly reported. However, there is no systematic study on the differential expression, prognostic significance and potential molecular mechanism of HOXA4 and HOXA5 in LUAD.In-house immunohistochemistry (IHC), multi-center microarrays, RT-qPCR and RNA-seq data were incorporated for comprehensively evaluating the expression and prognostic value of HOXA4 and HOXA5 in LUAD. The mechanism of HOXA4 and HOXA5 in the formation and development of LUAD was analyzed from multiple aspects of immune correlations, upstream transcriptional regulation, functional states of single cells and co-expressed gene network. The functional roles of HOXA4 and HOXA5 in LUAD were validated byAs a result, in 3201 LUAD samples and 2494 non-cancer lung samples, HOXA4 and HOXA5 were significantly downexpressed (P0.05). The aberrant expression of HOXA5 was significantly correlated with the clinical progression of LUAD (P0.05). HOXA5 showed remarkable prognostic value for LUAD patients (P0.05). The expression of HOXA4 and HOXA5 in LUAD were negatively correlated with tumor purity and positively correlated with the infiltration of various immune cells such as B cells, T cells and macrophages. HOXA4 and HOXA5 overexpression had notable inhibitory effect on the proliferation, migration and invasion of LUAD cells.In conclusion, the identified downexpressed HOXA4 and HOXA5 had significant distinguishing ability for LUAD samples and affected the cellular functions of LUAD cells. The low expression of HOXA5 indicated worse overall survival of LUAD patients. Therefore, the two HOXA family genes especially HOXA5 may serve as potential biomarkers for LUAD.

Background Lung cancer is one of the most commonly diagnosed malignancies worldwide, and the occurrence of venous thrombosis in combination with lung cancer seriously affects the survival prognosis of patients with lung cancer. This study aimed to delineate the publication status and trends in the literature related to thrombosis in lung cancer and to explore hotspots in research by conducting a bibliometric analysis. Methods Using the Web of Science database as the data source for bibliometric analysis, we searched the published research literature related to thrombosis in lung cancer from 1942 to 2022. Bibliometrix and VOSviewer were used to analyze key bibliometric indicators, including trends in the number of annual publications, countries, journals, author contributions, and research hotspots. Results A total of 378 papers related to thrombosis in lung cancer were screened, including 349 original articles and 29 reviews. The number of publications has increased rapidly in the last 20 years, and China and the United States have the largest number of publications. In the analysis of authors and journals, we found that the distribution of Chinese authors is relatively high in terms of the number of publications and their influence, while the journal sources are mainly dominated by oncology and thrombosis research journals. The analysis of the top 10 highly cited papers revealed that several studies involved the relationship between cancer and venous thrombosis and the exploration of cancer-related thrombotic risk factors. The keyword analysis showed that the papers mainly focused on the exploration of risk factors, in which related genes represented by ROS1 and immunotherapy gradually appeared in research on predicting thrombosis in lung cancer. Conclusions Research on thrombosis in lung cancer has developed rapidly in the past 20 years, with the largest number of studies coming from China. The main research hotspots are the exploration of risk factors, among which the association between related genes represented by ROS1, immunotherapy, and thrombosis in lung cancer-related events has brought us new thinking in the prevention of thrombosis in lung cancer.

Graphical abstract, Introduction The risk of infection with COVID-19 is high in lung adenocarcinoma (LUAD) patients, and there is a dearth of studies on the molecular mechanism underlying the high susceptibility of LUAD patients to COVID-19 from the perspective of the global differential expression landscape. Objectives To fill the research void on the molecular mechanism underlying the high susceptibility of LUAD patients to COVID-19 from the perspective of the global differential expression landscape. Methods Herein, we identified genes, specifically the differentially expressed genes (DEGs), correlated with the susceptibility of LUAD patients to COVID-19. These were obtained by calculating standard mean deviation (SMD) values for 49 SARS-CoV-2-infected LUAD samples and 24 non-affected LUAD samples, as well as 3931 LUAD samples and 3027 non-cancer lung samples from 40 pooled RNA-seq and microarray datasets. Hub susceptibility genes significantly related to COVID-19 were further selected by weighted gene co-expression network analysis. Then, the hub genes were further analyzed via an examination of their clinical significance in multiple datasets, a correlation analysis of the immune cell infiltration level, and their interactions with the interactome sets of the A549 cell line. Results A total of 257 susceptibility genes were identified, and these genes were associated with RNA splicing, mitochondrial functions, and proteasomes. Ten genes, MEA1, MRPL24, PPIH, EBNA1BP2, MRTO4, RABEPK, TRMT112, PFDN2, PFDN6, and NDUFS3, were confirmed to be the hub susceptibility genes for COVID-19 in LUAD patients, and the hub susceptibility genes were significantly correlated with the infiltration of multiple immune cells. Conclusion In conclusion, the susceptibility genes for COVID-19 in LUAD patients discovered in this study may increase our understanding of the high risk of COVID-19 in LUAD patients.

Objective. YuPingFeng Granules (YPFGs) is an herbal formula clinically used in China for more than 100 years to treat pneumonia. Nevertheless, the mechanism of YPFG in pneumonia treatment has not been established. This network pharmacology-based strategy has been performed to elucidate active compounds as well as mechanisms of YPFG in pneumonia treatment. Methods. First, active compounds of YPFG were identified in the traditional Chinese medicine systems pharmacology (TCMSP) database, and then the targets related to the active compounds were obtained from TCMSP and Swiss Target Prediction databases. Next, using DisGeNET, DrugBank, and GeneCards databases, we got therapeutic targets of pneumonia and common targets between pneumonia targets and YPFG. After that, a protein-protein interaction (PPI) network of pneumonia composed of common targets was built to analyze the interactions among these targets, which focused on screening for hub targets by topology. Then, online software and the ClusterProfiler package were utilized for the enrichment analysis of gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) data. Finally, the visualization software of Autodock was used for molecular docking among the hub target proteins. Results. 10 hub genes were selected by comparing the GO and KEGG functions of pneumonia targets with those of the common targets of YPFG and pneumonia. By using molecular docking technology, a total of 3 active ingredients have been verified as being able to combine closely with 6 hub targets and contribute to their therapeutic effects. Conclusion. This research explored the multigene pharmacological mechanism of action of YPFG against pneumonia through network pharmacology. The findings present new ideas for studying the mechanism of action of Chinese medicine against pneumonia caused by bacteria.

The clinical progression of small-cell lung cancer (SCLC) remains pessimistic. The aim of the present study was to promote the understanding of the clinical significance and mechanism of O-linked N-acetylglucosamine (GlcNAc) transferase (OGT) in SCLC. Wilcoxon tests, standardized mean difference (SMD), and Kruskal–Wallis tests were utilized to compare OGT level differences among the experimental and control groups. The univariate Cox regression analysis, Kaplan–Meier curves, and receiver operating characteristic curves were applied to determine OGT’s clinical relevance in cancers. The Spearman correlation analysis and enrichment analysis were utilized to explore the underlying mechanisms of OGT in cancers. For the first time in the field, we provide an overview of OGT in 32 cancers using a large number of samples (n = 21,196), determining distinct OGT expression in 25 cancers and its prognosis effects in 12 cancers. Furthermore, using 950 samples from multiple sources, upregulated OGT was found in both mRNA and protein levels in SCLC (SMD = 0.93, 95% CI [0.24, 1.63]). Higher OGT levels represented a more unfavorable disease-free interval for SCLC patients ( p < 0.001 ). The research also identified OGT expression as a potential marker for SCLC prediction (sensitivity = 0.79, specificity = 0.86, and AUC = 0.88). The high expression of OGT in SCLC may result from the positive regulation of two transcription factors—DEK and XRN2. We primarily investigated the underlying mechanisms of OGT in SCLC. Herein, based on the analyses from pan-cancer to SCLC, OGT demonstrated conspicuous clinical significance. OGT may be an underlying biomarker for the treatment and identification of some cancers, including SCLC.

Background: The clinical value of pyroptosis-related genes (PRGs) in lung adenocarcinoma (LUAD) remains obscure. Objective: The study attempts to explore PRGs in LUAD, which will enable an understanding of LUAD from the perspective of PRGs. Method: Lung adenocarcinoma patients were diagnosed using pathology, and their clinical information was collected from several public databases. A PRGs prognostic signature (PPS) for LUAD patients was established based on a multivariate Cox regression analysis. The differential expression of PRGs was identified using standardized mean differences in 6,958 samples. The area under the curve (AUC) was used to evaluate the predictive effects of the PPS to determine the survival rate of LUAD patients. Decision curve analysis was utilized to assess the clinical significance of the PPS in LUAD. Results: The PPS consists of five PRGs, namely CASP3, CASP9, GSDMB, NLRP1, and TNF. The prognostic effect of the PPS is evident in all the predicted one-, three-, and five-year survival rates (AUCs ≥ 0.58). The PPS represents an independent risk factor for the prognosis of LUAD patients (hazard ratio > 1; 95% confidence interval excluding 1). The PPS risk score can predict the prognosis of LUAD patients more accurately than PRGs of the PPS and multiple clinical parameters, such as age, tumor stage, and clinical stage. The decision curve analysis revealed that the nomogram based on the PPS and clinical parameters might result in better clinical decisions. Conclusion: The PPS makes it feasible to distinguish LUAD from non-LUAD. Thus, the underlying significance of the PPS in distinguishing LUAD from non-LUAD is promising.

The purpose of this study is to investigate the significance of alpha-enolase (ENO1) expression in squamous cell carcinoma of the lung (LUSC), its prognostic value, and prospective molecular mechanism. Using multiplatforms data, including in-house immunohistochemistry, in-house real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), in-house microarray, and public high-throughput data, the expression significance and prognostic role of ENO1 in LUSC tissues were analyzed comprehensively. With the combination of all eligible cases, compared with 941 non-LUSC lung tissues, ENO1 was significantly overexpressed in 1163 cases of LUSC (standardized mean difference (SMD) = 1.23, 95% confidence interval (CI) = 0.76–1.70, P P = 0.043). ENO1 and its related genes mainly participated in the pathways of cell division and proliferation. In conclusion, the upregulation of ENO1 could affect the carcinogenesis and unfavorable outcome of LUSC.

This study aimed to investigate the clinicopathological significance and prospective molecular mechanism of RUNX family transcription factor 2 (RUNX2) in lung squamous cell carcinoma (LUSC). The authors used immunohistochemistry (IHC), RNA‐seq, and microarray data from multi‐platforms to conduct a comprehensive analysis of the clinicopathological significance and molecular mechanism of RUNX2 in the occurrence and development of LUSC. RUNX2 expression was significantly higher in 16 LUSC tissues than in paired non‐cancerous tissues detected by IHC (P

RUNX family transcription factor 2 (RUNX2) overexpression has been found in various human malignancies. However, the expression levels of RUNX2 mRNA and protein in lung adenocarcinoma (LUAD) were not investigated. This study aims to thoroughly analysis the expression level and potential mechanisms of RUNX2 mRNA in LUAD. We applied in-house immunohistochemistry, high-throughput RNA-sequencing, and gene microarrays to comprehensively investigate the expression level of RUNX2 in LUAD. A pool standard mean difference (SMD) and summary receiver operating characteristic curves (SROC) were calculated to assess the integrated expression value of RUNX2 in LUAD. The hazard ratios (HRs) were integrated to evaluate the overall prognostic effect of RUNX2 on the LUAD patients. The differentially expressed genes (DEGs) of LUAD, the potential target genes of RUNX2, and its co-expressed genes were overlapped to obtain a set of specific genes for GO and KEGG enrichment analyses. RUNX2 overexpression in LUAD was validated using a large number of cases (2 418 LUAD and 1 574 non-tumor lung samples). The pooled SMD was 0.85 (95 % CI: 0.64-1.05) and the area under the curve (AUC) of the SROC was 0.86 (95 %CI: 0.83-0.89). The integrated HR was 1.20 [1.04-1.38], indicating that increased expression of RUNX2 was an independent risk factor for the poor survival of the LUAD patients. RUNX2 and its transcriptionally regulates potential target genes may promote cell proliferation and drug resistance of LUAD by modulating the cell cycle and MAPK signaling pathways. RUNX2 can provide new research directions for targeted drug therapy and drug resistance for LUAD treatment.

Background Lung adenocarcinoma (LUAD) is the main pathological type of pulmonary malignant tumors. Synaptojanin 2 (SYNJ2), a member of the synaptojanin family, is considered as an attractive underlying therapeutic target in several types of cancer. The purpose of the current research was to comprehensively investigate the molecular function and underlying mechanism of SYNJ2 in LUAD with the goal of providing a promising therapeutic target for LUAD. Methods We applied tissue microarrays, immunohistochemistry (IHC), high-throughput RNA sequencing (RNA-seq) data, and gene microarrays of public databases to comprehensively examine the protein level, mRNA expression, clinical significance, and prognosis value of SYNJ2 in LUAD. The standard mean difference (SMD) and summary receiver operating characteristic curves (SROC) were computed to evaluate the comprehensive expression value of SYNJ2 in LUAD. Kaplan-Meier survival curves were plotted to determine the overall survival of SYNJ2 with different expression levels in LUAD. Univariate and multivariate cox regression analyses were implemented to investigate the dependent prognostic ability of SYNJ2 expression and the clinically-relevant traits of LUAD. Moreover, SYNJ2 co-expressed genes were screened for Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) function analysis and protein–protein interactions (PPI) network construction. Results SYNJ2 overexpression in LUAD was confirmed by 2,299 LUAD samples and 1,387 non-tumor tissues obtained from tissue microarrays along with TCGA and public gene microarrays. The pooled SMD was 1.29 (95% CI: 1.09-1.48, I-square=78.6%, P

Background To investigate the clinical features of septic pulmonary embolism (SPE) cases and prognostic factors for in-hospital mortality in China. Methods A retrospective analysis was conducted of SPE patients hospitalized between January 2007 and June 2018 in the Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Guangxi Medical University. Results A total of 98 patients with SPE were identified. All patients had bilateral multiple peripheral nodules on chest computed tomography. The most common pathogen found in blood culture was Staphylococcus aureus (10/33, 30.3%). Transthoracic echocardiography was performed in 39 patients and 20 showed vegetations. Bronchoscopy was performed in 24 patients. Bronchoalveolar lavage fluid (BALF) was obtained from 15 patients (62.5%) and showed predominantly polymorphonuclear cell infiltration (52%, range of 48%~ 63%). Four patients received transbronchial lung biopsy, and histopathological examinations revealed suppurative pneumonia and organizing pneumonia. The in-hospital mortality rate was 19.4%. Age (odds ratio [OR] 1.100; 95% confidence interval [CI] 1.035–1.169), hypotension (OR 7.260; 95% CI 1.126–46.804) and ineffective or delay of empirical antimicrobial therapy (OR 7.341; 95% CI 1.145–47.045) were found to be independent risk factors for in-hospital mortality, whereas drainage treatment was found to be a protective factor (OR 0.33; 95% CI 0.002–0.677). Conclusions SPE cases presented with nonspecific clinical manifestations and radiologic features. Blood cultures and bronchoscopy are important measures for early diagnosis and differential diagnosis. There is relationship between primary infection sites and the type of pathogen. Maintaining normal blood pressure and providing timely and appropriate initial antimicrobial therapy for effective control of the infection could improve prognosis.

Aspergillus (A.) fumigatus, one of the most common causes of life-threatening fungal infections in immunocompromised patients, shows resistance to antifungal agents as has a high propensity to forming a biofilm. The present study aimed to investigate the effects of chlorogenic acid (CRA) on A. fumigatus biofilm formation and integrity. Confocal laser scanning microscopy was performed to determine the inhibitory effects of CRA against A. fumigatus biofilm formation. Transmission electron microscopy was performed to investigate the ultrastructural changes of A. fumigatus biofilm after CRA exposure. High-performance liquid chromatography and reverse-transcription quantitative PCR were performed to determine the expression of gliotoxin production in biofilm culture. The results showed that CRA at sub-minimum inhibitory concentrations inhibited A. fumigatus biofilm formation. In addition, CRA could decreased the gliotoxin production in the biofilm culture supernatant through inhibiting the expression of master genes involved in gliotoxin biosynthesis. The present study provided useful information for the development of novel strategies to reduce the incidence of A. fumigatus biofilm-associated diseases.

Background MiR-182-5p, a cancer-related microRNA (miRNA), modulates tumorigenesis and patient outcomes in various human malignances. This study interroted the clinicopathological significance and molecular mechanisms of miR-182-5p in non-small cell lung cancer (NSCLC). Methods The clinical significance of miR-182-5p in NSCLC subtypes was determined based on an analysis of 124 samples (lung adenocarcinomas [LUADs], n = 101; lung squamous cell carcinomas [LUSCs], n = 23) obtained from NSCLC patients and paired noncancer tissues and an analysis of data obtained from public miRNA-seq database, miRNA-chip database, and the scientific literature. The NSCLC samples (n = 124) were analyzed using the real-time quantitative polymerase chain reaction (RT-qPCR). Potential targets of miR-182-5p were identified using lists generated by miRWalk v.2.0, a comprehensive atlas of predicted and validated targets of miRNA-target interactions. Molecular events of miR-182-5p in NSCLC were unveiled based on a functional analysis of candidate targets. The association of miR-182-5p with one of the candidate target genes, homeobox A9 (HOXA9), was validated using in-house RT-qPCR and dual-luciferase reporter assays. Results The results of the in-house RT-qPCR assays analysis of data obtained from public miRNA-seq databases, miRNA-chip databases, and the scientific literature all supported upregulation of the expression level of miR-182-5p level in NSCLC. Moreover, the in-house RT-qPCR data supported the influence of upregulated miR-182-5p on malignant progression of NSCLC. In total, 774 prospective targets of miR-182-5p were identified. These targets were mainly clustered in pathways associated with biological processes, such as axonogenesis, axonal development, and Ras protein signal transduction, as well as pathways involved in axonal guidance, melanogenesis, and longevity regulation, in multiple species. Correlation analysis of the in-house RT-qPCR data and dual-luciferase reporter assays confirmed that HOXA9 was a direct target of miR-182-5p in NSCLC. Conclusions The miR-182-5p expression level was upregulated in NSCLC tissues. MiR-182-5p may exert oncogenic influence on NSCLC through regulating target genes such as HOXA9.

Pseudomonas aeruginosa is an opportunistic pathogen that causes severe airway infections in humans. These infections are usually difficult to treat and associated with high mortality rates. While colonizing the human airways, P. aeruginosa could accumulate genetic mutations that often lead to its better adaptability to the host environment. Understanding these evolutionary traits may provide important clues for the development of effective therapies to treat P. aeruginosa infections. In this study, 25 P. aeruginosa isolates were longitudinally sampled from the airways of four ventilator-associated pneumonia (VAP) patients. Pacbio and Illumina sequencing were used to analyse the in vivo evolutionary trajectories of these isolates. Our analysis showed that positive selection dominantly shaped P. aeruginosa genomes during VAP infections and led to three convergent evolution events, including loss-of-function mutations of lasR and mpl, and a pyoverdine-deficient phenotype. Specifically, lasR encodes one of the major transcriptional regulators in quorum sensing, whereas mpl encodes an enzyme responsible for recycling cell wall peptidoglycan. We also found that P. aeruginosa isolated at late stages of VAP infections produce less elastase and are less virulent in vivo than their earlier isolated counterparts, suggesting the short-term in vivo evolution of P. aeruginosa leads to attenuated virulence.

The (1-3)-β-D-Glucan (BG) assay has been approved for making a diagnosis of invasive fungal disease. However, the role of serum-BG assay for the diagnosis of pneumocystis pneumonia (PCP) is controversial, especially between patients with human immunodeficiency virus (HIV) and non-HIV. We conducted a meta-analysis to determine the difference of the overall accuracy of serum-BG assay for the diagnosis of PCP in immunocompromised patients with and without HIV.After a systematic review of English-language studies and manual researching, sensitivity (Se), specificity (Sp), and other measures of accuracy of serum-BG for the diagnosis of PCP were pooled using random-effects models for bivariate meta-analysis. Summary receiver operating characteristic (SROC) curve was used to summarize overall test performance. Subgroup analyses were performed to explore the heterogeneity in Se and Sp.Thirteen studies met our inclusion criteria. The summary estimates for serum-BG assay for definite PCP were as follows: Se, 0.91 [95% confidence interval (CI), 0.88-0.93]; Sp, 0.75 (95% CI, 0.68-0.81). As for the patients with and without HIV, the Se and Sp were 0.92 and 0.78, 0.85 and 0.73, respectively. Significant heterogeneity between Se was presented (P=0.04).Contrary to the results of the previous meta-analysis, a negative result of serum-BG determination is sufficient for ruling out PCP only in HIV cases. For non-HIV patients, the results should be interpreted in parallel with clinical and radiological findings. Besides, further prospective studies with larger sample size are needed to confirm the diagnosis strategy of BG detection.

Objective To establish an animal model of P.aeruginosa biofilm associated with chronic pulmonary infection and investigate the pathogenic effects of biofilm. Methods Experiments in vitro, measuring the MICS, MBCS of levofloxacin(LFX), ceftazidime(CAZ) in PAO579 in alginate beads and planktonic PAO579. Rats were challenged with 0.1 ml of PAO579(109CFU/ml) in alginate beads or 0.1 ml of planktonic PAO579(109 CFU/ml), 3,7,14 days after challenging, bacteriological, pathological features were observed. Results The MICS, MBCS of LFX, CAZ in PAO579 in alginate beads were higher than those in planktonic PAO579 in vitro. CFU/lung in alginate beads group was significantly higher than that in planktonic bacteria group(P =0.002, P =0.004, P = 0.002, respectively); macroscopic lung pathology and the inflammation in alginate beads group were significantly more severe compared to those in planktonic bacteria group in vivo. Conclusion P.aeruginosa biofilm protected bacterium from killing of antibiotics and might mediate the host immune damage in the lung tissue and made bacterium evade the host immune defense.

A serum galactomannan (GM) assay has been approved for diagnosing invasive aspergillosis (IA). However, the role of the BAL-GM assay has not been well established. Therefore, we conducted a metaanalysis to determine the overall accuracy of BAL-GM in the diagnosis of IA.After a systematic review of English-language studies, the sensitivity (SEN), specificity (SPE), and positive and negative likelihood ratios (PLR and NLR, respectively) of BAL-GM for the diagnosis of IA were pooled using a bivariate metaanalysis. Hierarchic summary receiver operating characteristic curves were used to summarize overall test performance. Potential between-study heterogeneity was explored by subgroup analyses. We calculated posttest probability to evaluate clinical usefulness.Twelve reports, including 13 studies, met our inclusion criteria. The summary estimates of the BAL-GM assay for proven or probable IA were as follows: SEN, 0.90 (95% CI, 0.79-0.96); SPE, 0.94 (95% CI, 0.90-0.96); PLR, 14.87 (95% CI, 8.89-24.90); and NLR, 0.10 (95% CI, 0.04-0.24). The four summary estimates of the BAL-GM assay for proven IA were 0.94 (95% CI, 0.86-0.98), 0.79 (95% CI, 0.68-0.86), 4.41 (95% CI, 2.87-6.77), and 0.07 (95% CI, 0.03-0.09), respectively. Significant heterogeneity was present.BAL-GM determination is a sensitive and specific test for the diagnosis of proven and probable IA. The measurement of BAL-GM is thus likely to be a useful tool for diagnosing IA. Further studies focused on the impact of treatment agents are needed.