Correlation between the gut microbiota characteristics of hosts with severe acute pancreatitis and secondary intra-abdominal infection.

Objective: The objective of the study is to investigate the changes in the composition of intestinal microecology in severe acute pancreatitis (SAP) patients with or without intra-abdominal infection and also to analyze the expression of antibiotic resistance genes to provide evidence for early warning of infectious diseases and the rational use of antibiotics. Methods: Twenty patients with SAP were enrolled in the study. According to whether the enrolled patients had a secondary intra-abdominal infection, they were divided into two groups, each consisting of 10 patients. Stool specimens were collected when the patients were admitted to the emergency intensive care unit (EICU), and nucleic acid extraction was performed. Next-generation gene sequencing was used to compare the differences in intestinal microflora diversity and drug resistance gene expression between the two groups. Results: The gut microbiota of patients in the infection group exhibited distribution on multiple clustered branches with some intra-group heterogeneity, and their flora diversity was compromised. The infected group showed an enrichment of various opportunistic bacteria in the gut microbiota, along with a high number of metabolic functions, stress functions to external signals, and genes associated with pathogenesis. Drug resistance genes were expressed in the gut microbiota of both groups, but their abundance was significantly lower in the non-infected group. Conclusion: The intestinal microbiota of patients in the infection group exhibited distribution on multiple clustered branches with some intra-group heterogeneity, and their flora diversity was compromised. Additionally, drug resistance genes were expressed in the gut microbiota of both groups, although their abundance was significantly lower in the non-infected group.

Metagenomic next-generation sequencing assisted in the successful treatment of pneumonia caused by Talaromyces marneffei in an immunocompetent patient.

INTRODUCTION: Talaromyces marneffei (T. marneffei), a kind of endemic opportunistic pathogen, was previously thought to occur in HIV-positive individuals and non-HIV hosts with impaired immune function. However, the infection of T. marneffei in patient with normal immune function was rarely reported. CASE PRESENTATION: We report a case of severe pneumonia caused by T. marneffei in an immunocompetent and HIV-negative patient, which was rapidly confirmed by metagenomics next-generation sequencing (mNGS) and treated successfully. The patient was a previously healthy 63-year-old male, who was admitted to hospital with fever for 11 days, cough and sputum for 1 week, and chest distress for 4 days. The infection of T. marneffei was quickly determined by alveolar lavage under bedside bronchoscope and mNGS test. RESULTS: Patient's condition improved rapidly after voriconazole treatment, and he was evaluated as a HIV-negative case of T. marneffei infection with normal immune function. This is a sporadic case of T. marneffei in non-endemic areas, and mNGS played a very important role in the treatment of the disease. The patient's immune function was relatively normal which was rare in clinical practice.

Enhancing lower respiratory tract infection diagnosis: implementation and clinical assessment of multiplex PCR-based and hybrid capture-based targeted next-generation sequencing.

BACKGROUND: Shotgun metagenomic next-generation sequencing (mNGS) is widely used to detect pathogens in bronchoalveolar lavage fluid (BALF). However, mNGS is complex and expensive. This study explored the feasibility of targeted next-generation sequencing (tNGS) in distinguishing lower respiratory tract infections in clinical practice. METHODS: We used 229 retrospective BALF samples to establish thresholds and diagnostic values in a prospective cohort of 251 patients. After target pathogen selection, primer and probe design, optimization experiments, and bioinformatics analysis, multiplex PCR-based tNGS (mp-tNGS) and hybrid capture-based tNGS (hc-tNGS), targeting 198 and 3060 pathogens (DNA and RNA co-detection workflow) were established and performed. FINDINGS: mp-tNGS and hc-tNGS took 10.3 and 16 h, respectively, with low sequencing data sizes of 0.1 M and 1 M reads, and test costs reduced to a quarter and half of mNGS. The LoDs of mp-tNGS and hc-tNGS were 50-450 CFU/mL. mp-tNGS and hc-tNGS were highly accurate, with 86.5% and 87.3% (vs. 85.5% for mNGS) sensitivities and 90.0% and 88.0% (vs. 92.1% for mNGS) specificities. tNGS detection rates for casual pathogens were 84.3% and 89.5% (vs. 88.5% for mNGS), significantly higher than conventional microbiological tests (P < 0.001). In seven samples, tNGS detected Pneumocystis jirovecii, a fungus not detected by mNGS. Whereas mNGS detected six samples with filamentous fungi (Rhizopus oryzae, Aureobasidium pullulans, Aspergillus niger complex, etc.) which missed by tNGS. The anaerobic bacteria as pathogen in eight samples was failed to detect by mp-tNGS. INTERPRETATION: tNGS may offer a new, broad-spectrum, rapid, accurate and cost-effective approach to diagnosing respiratory infections. FUNDING: National Natural Science Foundation of China (81625014 and 82202535).

Diagnostic performance of metagenomic sequencing in patients with suspected infection: a large-scale retrospective study.

Background: Metagenomic next-generation sequencing (mNGS) has been widely reported to identify pathogens in infectious diseases (IDs). In this work, we intended to investigate the diagnostic value and clinical acceptance of paired-samples mNGS as compared to the culture method. Methods: A total of 361 patients with suspected infection were retrospectively included. With reference to the clinical diagnosis, we compared the diagnostic performance and clinical acceptance in pathogen detection between mNGS and culture tests. Moreover, the pathogen concordance of paired blood and respiratory tract (RT) samples in mNGS assay was investigated. Results: Among 511 samples, 62.04% were shown to be pathogen positive by mNGS, and that for clinical diagnosis was 51.86% (265/511). When compared to culture assay (n = 428), mNGS had a significantly higher positivity rate (51.87% vs. 33.18%). With reference to the clinical diagnosis, the sensitivity of mNGS outperformed that of culture (89.08% vs. 56.72%). Importantly, mNGS exhibited a clinically accepted rate significantly superior to that of culture. In addition, the mNGS result from 53 paired blood and RT samples showed that most pairs were pathogen positive by both blood and RT, with pathogens largely being partially matched. Conclusion: Through this large-scale study, we further illustrated that mNGS had a clinically accepted rate and sensitivity superior to those of the traditional culture method in diagnosing infections. Moreover, blood and paired RT samples mostly shared partial-matched positive pathogens, especially for pathogens with abundant read numbers in RT, indicating that both blood and RT mNGS can aid the identification of pathogens for respiratory system infection.

Retrospective clinical and microbiologic analysis of metagenomic next-generation sequencing in the microbiological diagnosis of cutaneous infectious granulomas.

BACKGROUND: Cutaneous infectious granulomas (CIG) are localized and chronic skin infection caused by a variety of pathogens such as protozoans, bacteria, worms, viruses and fungi. The diagnosis of CIG is difficult because microbiological examination shows low sensitivity and the histomorphological findings of CIG caused by different pathogens are commonly difficult to be distinguished. OBJECTIVE: The objective of this study is to explore the application of mNGS in tissue sample testing for CIG cases, and to compare mNGS with traditional microbiological methods by evaluating sensitivity and specificity. METHODS: We conducted a retrospective study at the Department of Dermatology of Sun Yat-sen Memorial Hospital, Sun Yat-sen University from January 1st, 2020, to May 31st, 2024. Specimens from CIG patients with a clinical presentation of cutaneous infection that was supported by histological examination were retrospectively enrolled. Specimens were delivered to be tested for microbiological examinations and mNGS. RESULTS: Our data show that mNGS detected Non-tuberculosis mycobacteria, Mycobacterium tuberculosis, fungi and bacteria in CIG. Compared to culture, mNGS showed a higher positive rate (80.77% vs. 57.7%) with high sensitivity rate (100%) and negative predictive value (100%). In addition, mNGS can detect more pathogens in one sample and can be used to detect variable samples including the samples of paraffin-embedded tissue with shorter detective time. Of the 21 patients who showed clinical improvement within a 30-day follow-up, eighteen had their treatments adjusted, including fifteen who continued treatment based on the results of mNGS. CONCLUSIONS: mNGS could provide a potentially rapid and effective alternative detection method for diagnosis of cutaneous infectious granulomas and mNGS results may affect the clinical prognosis resulting from enabling the patients to initiate timely treatment.

Comparison of targeted next-generation sequencing and metagenomic next-generation sequencing in the identification of pathogens in pneumonia after congenital heart surgery: a comparative diagnostic accuracy study.

BACKGROUND: This study aimed to compare targeted next-generation sequencing (tNGS) with metagenomic next-generation sequencing (mNGS) for pathogen detection in infants with severe postoperative pneumonia after congenital heart surgery. METHODS: We conducted a retrospective observational study using data from the electronic medical record system of infants who developed severe pneumonia after surgery for congenital heart disease from August 2021 to August 2022. Infants were divided into tNGS and mNGS groups based on the pathogen detection methods. The primary outcome was the efficiency of pathogen detection, and the secondary outcomes were the timeliness and cost of each method. RESULTS: In the study, 91 infants were included, with tNGS detecting pathogens in 84.6% (77/91) and mNGS in 81.3% (74/91) of cases (P = 0.55). No significant differences were found in sensitivity, specificity, PPA, and NPA between the two methods (P > 0.05). tNGS identified five strains with resistance genes, while mNGS detected one strain. Furthermore, tNGS had a faster detection time (12 vs. 24 h) and lower cost ($150 vs. $500) compared to mNGS. CONCLUSION: tNGS offers similar sensitivity to mNGS but with greater efficiency and cost-effectiveness, making it a promising approach for respiratory pathogen detection.

Predictive performance of Metagenomic Next Generation Sequencing in early detection of post-liver transplantation infections.

Objective: To evaluate the predictive performance of metagenomic next-generation sequencing (mNGS) in identifying and predicting pulmonary infections following liver transplantation and to investigate its association with patient outcomes within the initial four-week post-transplantation period. Methods: We retrospectively analyzed 41 liver transplant patients with suspected pulmonary infections from August 2022 to May 2023. Bronchoalveolar lavage fluid (BALF) samples were collected on the first postoperative day for metagenomic next generation sequencing (mNGS) and culture. The predictive capability of mNGS for subsequent infections was assessed by monitoring inflammatory biomarkers and comparing the detection rates with culture methods. Real-time Polymerase Chain Reaction (Rt-PCR) was used to monitor Human betaherpesvirus 5 (CMV) and Human parvovirus B19 (B19) weekly during a four-week postoperative period. Inflammatory biomarkers and blood coagulation function were evaluated on specific days throughout the first, third, fifth, and during four weeks following surgery. The study was conducted until August 2023 to evaluate the patients' prognostic survival outcome, classifying them into groups based on the mortality and survival. Results: The analysis included a total of 41 patients, comprising 32 males and 9 females, with an average age of 52 (47, 63) years. Within one week after liver transplantation, there were 7 cases of bacterial infections, 5 cases of fungal infections, 19 cases of mixed infections, 8 cases without any infection, and 2 cases with unidentified pathogen-associated infections. mNGS successfully predicted 39 (72 %) strains of pathogens, while culture-based methods only detected 28 (52 %) strains. Among the 8 patients diagnosed as non-infected, culture methods identified positive results in 4 cases (50 %), whereas mNGS yielded positive results in 7 cases (87.5 %). The detection rates of CMV and B19 by Rt-PCR within 4 weeks after liver transplantation were 61 % and 17 %, respectively (25/41, 7/41) among the patients. During the study period, a total of 9 patients succumbed while 32 patients survived. The death group and the survival group exhibited significant differences in CRP, HGB, and INR levels at specific monitoring time points. The proportion of CMV detection in blood was significantly higher in the death group compared to the surviving group. Elevated CRP level was identified as a prognostic risk factor. Conclusions: Despite the presence of false positives, mNGS still presents a potential advantage in predicting pulmonary infection pathogens following liver transplantation. Furthermore, the levels of CRP and CMV carrier status within four weeks post-surgery exhibit significant associations with patient survival and prognosis.

Metagenomic next-generation sequencing promotes pathogen detection over culture in joint infections with previous antibiotic exposure.

Objective: To investigate the diagnostic value of metagenomic next-generation sequencing (mNGS) in detecting pathogens from joint infection (JI) synovial fluid (SF) samples with previous antibiotic exposure. Methods: From January 2019 to January 2022, 59 cases with suspected JI were enrolled. All cases had antibiotic exposure within 2 weeks before sample collection. mNGS and conventional culture were performed on SF samples. JI was diagnosed based on history and clinical symptoms in conjunction with MSIS criteria. The diagnostic values, including sensitivity, specificity, positive/negative predictive values (PPV/NPV), and accuracy, were in comparison with mNGS and culture. Results: There were 47 of the 59 cases diagnosed with JI, while the remaining 12 were diagnosed with non-infectious diseases. The sensitivity of mNGS was 68.1%, which was significantly higher than that of culture (25.5%, p<0.01). The accuracy of mNGS was significantly higher at 71.2% compared to the culture at 39.0% (p <0.01). Eleven pathogenic strains were detected by mNGS but not by microbiological culture, which included Staphylococcus lugdunensis, Staphylococcus cohnii, Finegoldia magna, Enterococcus faecalis, Staphylococcus saprophytics, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Acinetobacter pittii, Brucella ovis, andCoxiella burnetii. Antibiotic therapy was adjusted based on the mNGS results in 32 (68.1%) patients, including 12 (25.5%) and 20 (42.6%) patients, in whom treatment was upgraded and changed, respectively. All JI patients underwent surgery and received subsequent antibiotic therapy. They were followed up for an average of 23 months (20-27 months), and the success rate of treatment was 89.4%. Out of the 33 patients who had positive results for pathogens, reoperation was performed in 1 case (3.03%), while out of the 14 cases with negative results for both mNGS and cultures, reoperation was performed in 4 cases (28.6%). Conclusions: mNGS has advantages over conventional culture in detecting pathogens in SF samples from JI patients previously treated with antibiotics, potentially improving clinical outcomes.

Cryptococcus Neoformans Osteomyelitis of the Right Ankle Diagnosed by Metagenomic Next-Generation Sequencing in a HIV-Negative Patient with Tuberculous Lymphadenitis and Pulmonary Tuberculosis: A Case Report and Recent Literature Review.

Aim: Cryptococcus neoformans osteomyelitis coupled with tuberculosis and tuberculous lymphadenitis, is a rare occurrence in clinical. Diagnostic challenges arise due to the clinical radiological similarity of this condition to other lung infections and the limited and sensitive nature of traditional approaches. Here, we present a case of co-infection diagnosed using Metagenomic Next-Generation Sequencing, highlighting the effectiveness of advanced genomic techniques in such complex scenarios. Case Presentation: We present a case of a 67-year-old female infected with cryptococcal osteomyelitis and presented with swelling and pain in the right ankle. Following a biopsy of the right ankle joint, Metagenomic Next-Generation Sequencing (mNGS) of the biopsy tissue revealed Cryptococcus neoformans infection. Positive results for Cryptococcus capsular antigen and pathological findings confirmed the presence of Cryptococcus neoformans. The patient underwent surgical debridement, coupled with oral fluconazole treatment (300mg/day), leading to the resolution of symptoms. Conclusion: Cryptococcus neoformans is an uncommon cause of ankle infection. Metagenomic Next-Generation Sequencing (mNGS) serves as a valuable diagnostic tool, aiding clinicians in differentiating cryptococcal osteomyelitis from other atypical infections.

A case of Bartonella vinsonii endocarditis.

The diagnosis of Bartonella is challenging due to its rarity and negative culture results. Once the diagnosis is delayed and proper treatment is not given, it can develop into infective endocarditis, which can be fatal. We reported a 60-year-old female patient who had recurrent fever for 5 months. After receiving ineffective treatment at the local hospital, she sought medical attention at our hospital. Laboratory blood indicators testing and imaging indicated infective endocarditis, and metagenomic Next Generation Sequencing (m-NGS) testing confirmed the diagnosis of Bartonella vinsonii infection. After surgical treatment and the combination of doxycycline and ceftriaxone sodium for anti-infective therapy, the patient recovered. Valuing the combination of multiple auxiliary diagnostic methods and improving the application of m-NGS in the detection of unknown pathogens can compensate for the current limitations in the diagnosis of Bartonella. Early diagnosis and treatment are extremely important for Bartonella endocarditis.

Clinical evaluation of a highly multiplexed CRISPR-based diagnostic assay for diagnosing lower respiratory tract infection: a prospective cohort study.

OBJECTIVE: Accurate and rapid identification of causative pathogens is essential to guide the clinical management of lower respiratory tract infections (LRTIs). Here we conducted a single-centre prospective study in 284 patients suspected of lower respiratory tract infections to evaluate the utility of a nucleic acid test based on highly multiplexed polymerase chain reaction (PCR) and CRISPR-Cas12a. METHODS: We determined the analytical and diagnostic performance of the CRISPR assay using a combination of reference standards, including conventional microbiological tests (CMTs), metagenomic Next-Generation Sequencing (mNGS), and clinical adjudication by a panel of experts on infectious diseases and microbiology. RESULTS: The CRISPR assay showed a higher detection rate (63.0%) than conventional microbiological tests (38.4%) and was lower than metagenomic Next-Generation Sequencing (72.9%). In detecting polymicrobial infections, the positivity rate of the CRISPR assay (19.4%) was higher than conventional microbiological tests (3.5%) and lower than metagenomic Next-Generation Sequencing (28.9%). The overall diagnostic sensitivity of the CRISPR assay (67.8%) was higher than conventional microbiological tests (41.8%), and lower than metagenomic Next-Generation Sequencing (93.2%). CONCLUSIONS: Considering the low cost, ease of operation, short turnaround time, and broad range of pathogens detected in a single test, the CRISPR assay has the potential to be implemented as a screening tool for the aetiological diagnosis of lower respiratory tract infections patients, especially in cases where atypical bacteria or coinfections are suspected.

[Two cases of neonatal Legionella pneumonia]. / 新生儿嗜肺军团菌肺炎2例.

Patient 1, a 12-day-old female infant, presented with fever, cough, dyspnea, and elevated infection markers, requiring respiratory support. Metagenomic next-generation sequencing (mNGS) of blood and bronchoalveolar lavage fluid revealed Legionella pneumophila (LP), leading to diagnoses of LP pneumonia and LP sepsis. The patient was treated with erythromycin for 15 days and azithromycin for 5 days, resulting in recovery and discharge. Patient 2, an 11-day-old female infant, presented with dyspnea, fever, elevated infection markers, and multiple organ dysfunction, requiring mechanical ventilation. mNGS of blood and cerebrospinal fluid indicated LP, leading to diagnoses of LP pneumonia, LP sepsis, and LP intracranial infection. The patient was treated with erythromycin for 19 days and was discharged after recovery. Neonatal LP pneumonia lacks specific clinical symptoms, and azithromycin is the preferred antimicrobial agent. The use of mNGS can provide early and definitive diagnosis for severe neonatal pneumonia of unknown origin.

Exploring the clinical and diagnostic value of metagenomic next-generation sequencing for urinary tract infection: a systematic review and meta-analysis.

BACKGROUND: A new pathogen detection tool, metagenomic next-generation sequencing (mNGS), has been widely used for infection diagnosis, but the clinical and diagnostic value of mNGS in urinary tract infection (UTI) remains inconclusive. This systematic review with meta-analysis aimed to investigate the efficacy of mNGS in treating UTIs. METHODS: A comprehensive literature search was performed in PubMed, Web of Science, Embase, and the Cochrane Library, and eligible studies were selected based on the predetermined criteria. The quality of the included studies was assessed via the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool, and the certainty of evidence (CoE) was measured by the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) score. Then, the positive detection rate (PDR), pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve of the summary receiver operating characteristic curve (AUROC) was estimated in Review Manager, Stata, and MetaDisc. Subgroup analysis, meta-regression, and sensitivity analysis were performed to reveal the potential factors that influence internal heterogeneity. RESULTS: A total of 17 studies were selected for further analysis. The PDR of mNGS was markedly greater than that of culture (odds ratio (OR) = 2.87, 95% confidence interval [CI]: 1.72-4.81, p < 0.001, I2 = 90%). The GRADE score presented a very low CoE. Then, the pooled sensitivity was 0.89 (95% CI: 0.86-0.91, I2 = 39.65%, p = 0.06), and the pooled specificity was 0.75 (95% CI: 0.51-0.90, I2 = 88.64%, p < 0.001). The AUROC of the studies analyzed was 0.89 (95% CI: 0.86-0.92). The GRADE score indicated a low CoE. CONCLUSION: The current evidence shows that mNGS has favorable diagnostic performance for UTIs. More high-quality prospective randomized controlled trials (RCTs) are expected to verify these findings and provide more information about mNGS in UTI treatment and prognosis.

Comparative analysis of metagenomic and targeted next-generation sequencing for pathogens diagnosis in bronchoalveolar lavage fluid specimens.

Background: Although the emerging NGS-based assays, metagenomic next-generation sequencing (mNGS) and targeted next-generation sequencing (tNGS), have been extensively utilized for the identification of pathogens in pulmonary infections, there have been limited studies systematically evaluating differences in the efficacy of mNGS and multiplex PCR-based tNGS in bronchoalveolar lavage fluid (BALF) specimens. Methods: In this study, 85 suspected infectious BALF specimens were collected. Parallel mNGS and tNGS workflows to each sample were performed; then, we comparatively compared their consistency in detecting pathogens. The differential results for clinically key pathogens were confirmed using PCR. Results: The microbial detection rates of BALF specimens by the mNGS and tNGS workflows were 95.18% (79/83) and 92.77% (77/83), respectively, with no significant difference. mNGS identified 55 different microorganisms, whereas tNGS detected 49 pathogens. The comparative analysis of mNGS and tNGS revealed that 86.75% (72/83) of the specimens were complete or partial concordance. Particularly, mNGS and tNGS differed significantly in detection rates for some of the human herpesviruses only, including Human gammaherpesvirus 4 (P<0.001), Human betaherpesvirus 7 (P<0.001), Human betaherpesvirus 5 (P<0.05) and Human betaherpesvirus 6 (P<0.01), in which tNGS always had higher detection rates. Orthogonal testing of clinically critical pathogens showed a total coincidence rate of 50% for mNGS and PCR, as well as for tNGS and PCR. Conclusions: Overall, the performance of mNGS and multiplex PCR-based tNGS assays was similar for bacteria and fungi, and tNGS may be superior to mNGS for the detection of DNA viruses. No significant differences were seen between the two NGS assays compared to PCR.

Disseminated emergomyces orientalis infection in a patient with systemic lupus erythematosus.

A case of Eimonosis orientalis was reported in a 52-year-old male farmer who presented with cough, phlegm, fever, headache, and nausea for more than 4 days. Haemophilic cells and fungal spores were identified in the bone marrow smear and confirmed as Aemon orientalis by culture. The same bacteria were also isolated from blood cultures.

The clinical application value of multi-site mNGS detection of patients with sepsis in intensive care units.

BACKGROUND: Sepsis remains a leading cause of mortality in intensive care units, and rapid and accurate pathogen detection is crucial for effective treatment. This study evaluated the clinical application of multi-site metagenomic next-generation sequencing (mNGS) for the diagnosis of sepsis, comparing its performance against conventional methods. METHODS: A retrospective analysis was conducted on 69 patients with sepsis consecutively admitted to the Department of Intensive Care Medicine, Meizhou People's Hospital. Samples of peripheral blood and infection sites were collected for mNGS and conventional method tests to compare the positive rate of mNGS and traditional pathogen detection methods and the distribution of pathogens. The methods used in this study included a comprehensive analysis of pathogen consistency between peripheral blood and infection site samples. Additionally, the correlation between the pathogens detected and clinical outcomes was investigated. RESULTS: Of the patients with sepsis, 57.97% experienced dyspnea, and 65.2% had underlying diseases, with hypertension being the most common. mNGS demonstrated a significantly higher pathogen detection rate (88%) compared to the conventional method tests (26%). The pathogen consistency rate was 60% between plasma and bronchoalveolar lavage fluid samples, and that of plasma and local body fluid samples was 63%. The most frequently detected pathogens were gram-negative bacteria, and Klebsiella pneumonia. There were no significant differences in the clinical features between the pathogens. CONCLUSION: mNGS is significantly superior to conventional methods in pathogen detection. There was a notable high pathogen consistency detection between blood and local body fluid samples, supporting the clinical relevance of mNGS. This study highlights the superiority of mNGS in detecting a broad spectrum of pathogens quickly and accurately. TRIAL REGISTRATION: Not applicable.

Distribution characteristics of human herpes viruses in the lower respiratory tract and their impact on 30-day mortality in community-acquired pneumonia patients.

Human herpes viruses (HHVs) are commonly detected in community-acquired pneumonia (CAP) patients, particularly those with complex complications, attracting increased attention from clinical practitioners. However, the significance of detecting HHVs in bronchoalveolar lavage fluid (BALF) with CAP patients is still unclear. This study retrospectively analyzed BALF samples from 64 CAP patients at the Kunming Third People's Hospital between August 2021 and December 2023. Metagenomic next generation sequencing (mNGS) was conducted on BALF samples during CAP onset. Multivariate Cox regression models were used to identify independent risk factors for 30-day all-cause mortality in CAP. HHVs were found in 84.4% of CAP patients, which were the most common pathogens (45.1%), followed by bacteria (30.2%) and fungi (11.5%). Bacterial-viral co-infections were most common, occurring in 39 patients. Notably, there was no significant difference in HHV presence between severe and non-severe CAP patients (EBV: P = 0.431, CMV: P = 0.825), except for HHV-7 (P = 0.025). In addition, there was no significant difference in the 30-day mortality between HHV positive and HHV negative groups (P = 0.470), as well as between the HHV-7 positive and HHV-7 negative groups (P = 0.910). However, neither HHVs nor HHV-7 was independent risk factors for 30-day mortality in CAP patients (HHVs: HR 1.171, P = 0.888; HHV-7: HR 1.947, P = 0.382). In summary, among the prevalent presence of multiple HHVs, EBV and CMV were the most prevalent in CAP patients. Patients with sCAP were more susceptible to HHV-7 than those with non-sCAP. These results provide valuable insights for clinicians in guiding appropriate interventions for CAP treatment.

Clinical diagnostic value of metagenomic next-generation sequencing in patients with acute infection in emergency department.

Objective: To explore the value of metagenomic next-generation sequencing (mNGS) and culture in microbial diagnosis of patients with acute infection. Methods: We retrospectively analyzed 206 specimens from 163 patients who were admitted to the emergency department of The First Affiliated Hospital of Sun Yat-sen University between July 2020, and July 2021. We evaluated the diagnostic efficacy of mNGS and in-hospital traditional culture. Results: The total positive rate of mNGS was significantly higher than that culture methods (71.4 % vs 40.8 %, p < 0.001), while the sensitivity and accuracy of mNGS were found to be 92.9 % and 88.2 % respectively. However, culture exhibited superior specificity with a value of 92.6 % compared to 75.9 % for mNGS. The detection efficiency of mNGS and culture for fungi was comparable, but mNGS showed superior performance for bacterial detection. In the analysis of sepsis samples, mNGS outperformed traditional culture methods in diagnosing various types of samples, especially for sputum and bronchoalveolar lavage fluid. Among the identified infections, bacterial infections were the most common single infection (37.5 %). Additionally, bacterial-fungal infections represented the most prevalent form of mixed infection (77.3 %). Candida albicans and Staphylococcus aureus were identified as the predominant pathogens in the survival and death groups, respectively. No significant differences in microbial diversity were observed. Conclusion: Compared to culture methods, mNGS demonstrates superior positive rates, sensitivity, and accuracy in the rapid detection of acute infections, particularly in critically ill patients such as those with sepsis. This capability establishes a foundation for the swift and precise identification of pathogens, allowing for the analysis of clinical indicators and patient prognosis based on the extensive data generated from mNGS.

Microbial Heterogeneity Identification of Cerebral Thrombi Via Metagenomic Next-Generation Sequencing-Based Strategy.

BACKGROUND: Diagnosis of the cause of cerebral thrombi is vital for recurrence prevention but also challenging. The presence of the microbiome has recently been confirmed in thrombus, suggesting a novel approach to distinguish cerebral thrombi of different origins. However, little is known about whether there is heterogeneity in microbiological colonization of cerebral thrombi of different sources. METHODS AND RESULTS: Forty patients experiencing acute ischemic stroke were included and clinical data were collected. Metagenomic next-generation sequencing was adopted to detect bacterial and genomic signatures of human cerebral thrombi samples. We found similar species diversity between the large-artery atherosclerosis thrombi and cardioembolic thrombi but different species composition and distribution of cerebral thrombus microbiota. Compared with the group with cardioembolism, the group with large-artery atherosclerosis showed a significantly higher relative abundance of Ralstonia insidiosa among the top 10 bacterial species in cerebral thrombi. Twenty operational taxonomy units were correlated with 11 clinical indicators of ischemic stroke. The Gene Ontology enrichment analysis revealed 9 different enriched biological processes (translation and carbohydrate metabolic process, etc). The enriched Kyoto Encyclopedia of Genes and Genomes pathways included ribosome, butanoate metabolism, and sulfur metabolism. CONCLUSIONS: This study, based on the approach of metagenomic next-generation sequencing, provides a diagnostic microbiological method to discriminate individuals with cardioembolic thrombi from those with large-artery atherosclerosis thrombi with human cerebral thrombi samples. Our findings provide a fresh perspective on microbial heterogeneity of cerebral thrombi and demonstrate biological processes and pathway features of cerebral thrombi.

Pulmonary abscess caused by Streptococcus pseudopneumoniae in a child: A case report and review of literature.

BACKGROUND: Lung abscess found on chest X-ray and computed tomography examinations is rare in infants and young children. Several pathogens can cause lung abscesses, with the most common pathogens being anaerobes, Streptococci and Staphylococcus aureus. Streptococcus pseudopneumoniae (S. pseudopneumoniae) is a member of the Streptococcaceae family, and is mainly isolated from respiratory tract specimens. There are currently no cases of lung abscess caused by S. pseudopneumoniae in the literature. CASE SUMMARY: A 2-year-old boy was admitted to hospital due to persistent cough and fever. Lung computed tomography examination suggested the formation of a lung abscess. His diagnosis was not confirmed by testing for serum respiratory pathogens (6 items), respiratory pathogen nucleic acid (27 items), and laboratory culture. Finally, metagenomic next-generation sequencing of bronchoalveolar lavage fluid revealed the presence of S. pseudopneumoniae, confirming its role in causing the lung abscess. After receiving antibiotic treatment, reexamination with lung computed tomography showed that the abscess was resorbed and the patient's outcome was good. CONCLUSION: This is the first report of a lung abscess in a child caused by S. pseudopneumoniae infection. Metagenomic next-generation sequencing of bronchoalveolar lavage fluid is helpful in achieving rapid and accurate pathogen identification.