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Detection rate of pathogenic variants by postmortem genetic testing for sudden cardiac death among children and young adults: systematic review and meta-analysis.

PURPOSE: Postmortem genetic testing (PMGT) can clarify the causes of sudden cardiac death (SCD) in children and young adults and provide preventive care for relatives. We systematically reviewed studies to estimate the detection rate of pathogenic variants identified by PMGT in SCD cases aged 1-50 years and examined factors influencing detection rates. METHODS: Ovid MEDLINE and Ovid Embase were searched for observational studies on PMGT in cases of SCD, records in duplicate were screened, and study- and variant-level data were extracted. Risk of bias was assessed using the Joanna Briggs Institute checklist. The pooled detection rates were estimated using random-effects meta-analysis, and heterogeneity was explored based on subgroup and meta-regression analyses. RESULTS: Sixty-six studies (4,452 cases from 23 countries) were included. The pooled detection rate was 19% (95% confidence interval, 15% to 24%). Among the detected pathogenic variants, 76% were found in genes included on the ACMG Secondary Findings list. Higher detection rates were associated with earlier publication years, lower mean age, and lower risk of bias. Substantial between-study heterogeneity persisted (I2 = 91%) despite the subgroup and meta-regression analyses. CONCLUSION: PMGT can be used to identify pathogenic variants in young SCD cases, however, there is considerable heterogeneity in study conditions.

Forensic genetics

Aetiological studies on hospital inpatients with secretory diarrhoea in Calcutta.

Twenty-five cases of all age groups with secretory diarrhoea admitted to the Infectious Diseases Hospital, Calcutta were studied. Bacterial enteropathogens were detected by bacteriological examination of the faeces, in each and every case. The main pathogens detected were Escherichia coli and Vibrio cholerae. V cholerae was more commonly associated with severe illness except in the very young, while Esch coli was equally associated with moderate and severe illness. Multiple isolates were more commonly associated with severe illness and single isolates were more common in illness of moderate severity.

Adolescent

Etiology of childhood diarrhea in Beijing, China.

To determine the role of recently recognized enteropathogens in childhood diarrhea in China, 221 children with diarrhea and 108 controls seen at the Beijing Children's Hospital were studied during April and May 1989. Stools were examined for ova, parasites, and rotavirus, cultured for bacterial pathogens, and probed for enterotoxigenic Escherichia coli (ETEC), enteroinvasive E. coli (EIEC), enterohemorrhagic E. coli (EHEC), and enteropathogenic adherence factor-positive (EAF+) E. coli. Pathogens were identified in 56.5% of children with diarrhea and 43.5% of controls (P = 0.04). Detection of enteropathogens was significantly greater in patients examined within 1 week of symptom onset (65%) than in patients examined later (39%; P = 0.01). ETEC was the most frequently detected pathogen in children with diarrhea, accounting for 20% of the cases. Other agents identified in patients included the following: salmonellae, 12%; rotavirus, 7%; EIEC, 7%; EHEC, 7%; members of the Aeromonas hydrophila group, 6%; EAF+ E. coli, 5%; Ascaris lumbricoides, 3%; shigellae, 3%; campylobacters, 2%; and Vibrio spp., 0.5%. The isolation rates of salmonellae (P = 0.02), EAF+ E. coli (P = 0.04), and mixed pathogens (P = 0.05) were significantly greater for diarrhea patients than for controls. Resistance to multiple antimicrobial agents occurred in 39% of the Salmonella isolates, 22% of the Aeromonas isolates, and 17% of the Shigella isolates. Multiresistant salmonellae (P = 0.05) and shigellae were recovered from diarrheal stools only. Ciprofloxacin, cefotaxime, and imipenem were the only agents tested to which all bacterial isolates were susceptible in vitro. These results suggest that both traditional and newly recognized agents are important causes of childhood diarrhea in Beijing and that therapy may be complicated by indigenous antimicrobial resistance.

Child, Preschool

Isolation of Treponema hyodysenteriae from sources other than swine.

Fecal samples were collected from animals and environments on 3 swine farms and cultured for Treponema hyodysenteriae. Each farm was a farrow-to-finish operation and, at the time of sampling, swine dysentery was enzootic among 8- to 22-week-old pigs. Pathogenic T hyodysenteriae was isolated from pigs on all 3 farms. On farm A, nonpathogenic T hyodysenteriae was isolated from a sample of lagoon water. On farm B, pathogenic T hyodysenteriae was isolated from a waste-holding pit. On farm C, a dog was observed to be eating feces of pigs that had swine dysentery. The dog was diarrheic and a fecal sample yielded a pathogenic isolant of T hyodysenteriae. Further isolation attempts were unsuccessful after the dog was removed from the infected premises. Isolation of pathogenic and nonpathogenic organisms from waste-holding systems emphasizes the need for cultural techniques in detecting pathogenic T hyodysenteriae.

Animals

Using Mapping-Profiles to Refine Strain-Level Metagenomic Classification.

Metagenomic classification at the strain level remains challenging due to high sequence similarity among closely related genomes, which leads to ambiguous read mappings and frequent false-positive strain detections. Reducing such errors improves the reliability of strain-level analyses, which is critical for applications such as pathogen detection. We introduce StrainRefine, a post-mapping refinement method that analyzes read-reference mapping profiles to resolve ambiguous assignments among highly similar genomes. The method represents candidate reference genomes using binary profiles that capture read-support patterns and measures similarity between references based on profile overlap. The method clusters references based on similar mapping profiles, filters weakly supported genomes, and reassigns reads to representative references, reducing redundant reporting of near-identical strains. StrainRefine substantially reduces false-positive strain detections while preserving recall and improving agreement between predicted and true abundance profiles. On large-scale metagenomic datasets, it achieves a substantially improved precision-recall balance compared with existing mapping-based approaches, with the standalone method obtaining the highest read-level classification accuracy on the most complex evaluated dataset. Unlike many strain-level tools designed for individual species, StrainRefine operates without prior assumptions about sample composition or curated species-specific reference collections, while still achieving comparable performance in single-species settings on species-specific reference databases. These results highlight mapping-profile similarity as an effective signal for improving strain-level metagenomic classification.

false-positive reduction

A DNA probe specific to pathogenic Entamoeba histolytica.

A DNA sequence, IE-gen1 (3.1 kb), was isolated from the pathogenic strain of E. histolytica NIH-200. IE-gen1 was identified by the subtractive hybridization of a genomic library to a cDNA probe prepared from NIH-200 trophozoites. The IE-gen1 probe specifically detected pathogenic E. histolytica in slot blots of genomic DNA and Northern blots, but not other Entamoeba species and additional human parasites. This genomic probe could detect with complete specificity DNA from about 10(3) organisms. The IE-gen1 probe could be related to highly specialized loci in pathogenic E. histolytica, and is likely to be a valuable DNA reagent for clinical diagnosis and epidemiological investigations.

Animals

Cryptosporidium and diarrhoea in southern Indian children.

Cryptosporidium was detected more frequently in stool samples from southern Indian children with acute diarrhoea than from matched controls. It was seldom the only pathogen detected and was not associated with clearcut clinical features. The frequency of the protozoon in children under six months of age was higher in controls than in patients with acute diarrhoea. These features suggest that Cryptosporidium is unlikely to be a major cause of acute diarrhoea in this population. Frequency of Cryptosporidium was higher in children who had been given antibiotics and in those with prolonged episodes of diarrhoea. Administration of antibiotics may lead to conditions within the intestinal lumen that favour colonisation by the organism and prolongation of diarrhoeal episodes.

Acute Disease

Occurrence and significance of Cryptosporidium infection in Calcutta.

During a 2-year study, Cryptosporidium oocysts were detected in 32 (5.6%) of 566 hospitalized paediatric diarrhoea cases and 2 (1.2%) of 167 non-diarrhoeic individuals. Cryptosporidium was the sole pathogen detected in 17 (3.0%) of the 32 positive cases; in the other 15 it occurred in combination with one or more other established enteropathogen(s). The frequency of detection of the parasite was highest in the 0-6 months age group; no sex-specific difference was discernible. The detection rate of the parasite was highest during the monsoon and post-monsoon months. Most of the patients had watery stools with a mild to moderate degree of dehydration, with the diarrhoea lasting for less than 7 d.

Age Factors

Mapping Wastewater Pathogens and Their Associated Environmental and Public Health Risk Factors: A Systematic Review and Meta-Analysis.

BACKGROUND: Wastewater-based epidemiology (WBE) has emerged as a critical tool for public health surveillance, yet its application across diverse pathogens and geographical settings remains inconsistent. This systematic review synthesizes global evidence on wastewater surveillance to identify associated risk factors. METHODS: Following PRISMA 2020 guidelines (PROSPERO: CRD420261297382), a systematic search was conducted across PubMed, Scopus, Google Scholar, and Web of Science for studies published between 2000 and 2025. RESULTS: Thirty-nine peer-reviewed studies were included. The evidence base is geographically skewed toward the European Region (48.7%) and the Americas (23.1%), with significant underrepresentation in LMICs. Viruses were the primary biological target (89.7%), followed by bacteria (7.7%) and parasites (2.6%). A proportion meta-analysis of 31 eligible studies demonstrated a pooled wastewater pathogen detection prevalence of 62% (95% CI: 47.5-74.6%), with the European Region yielding the highest regional estimate (73%) and the African Region the lowest (8.3%). Conventional PCR and sequencing methods showed higher pooled detection rates (92.4% and 90.1%, respectively) than RT-qPCR (47.9%). CONCLUSION: WBE provides a robust early-warning system indicating a need for broader pathogen diversity, incorporating bacterial and parasitic surveillance and expansion into rural and resource-limited regions.

Contamination

Invisible Threats, Relentless Hunters: Biosurveillance of Airborne Plant Pathogens.

Airborne dispersal enables plant pathogens to travel across fields, regions, and continents, fueling rapid epidemics and emerging disease threats. Biosurveillance, the systematic monitoring of airborne inoculum, offers the opportunity to detect pathogens before symptoms appear and informs timely, risk-based management. Recent advances in air sampling, molecular diagnostics, metagenomics, and imaging technologies have expanded the scale and resolution of pathogen monitoring, from single-species qPCR assays to community-level aerobiome surveys. Integration of biosurveillance data with decision-support systems, remote sensing, and artificial intelligence is transforming early-warning capabilities and providing novel insights into pathogen ecology, evolution, and fungicide resistance. Yet major challenges remain, including assay standardization, data interpretation, and translation into actionable tools for growers. This review synthesizes current approaches, highlights case studies in which biosurveillance has advanced disease management, and outlines future directions toward coordinated surveillance networks and precision agriculture applications.

Air Microbiology

Immunological methods for detection of foodborne pathogens and their toxins.

Improved methods to detect microorganisms and their toxins introduced during the last decade involve among others recombinant DNA techniques and various immuno-assays such as the enzyme-linked immunosorbent assay and the latex agglutination. Immuno-assays are based on a quantitative reaction of an antigen (bacterial metabolite, e.g., toxin) with its antibody. Therefore, they are suited for detection of microorganisms based on their production of specific antigens and for quantitative detection of bacterial toxins. Sensitivity and specificity of immuno-assays are mainly determined by the antiserum used. In this respect the use of well selected monoclonal antibodies can be of advantage. With the enzyme-linked immunosorbent assay and latex agglutination test quantities of 0.1-1 ng of antigen/ml can be detected. Of both techniques the latex agglutination method has several advantages; the method is simple, inexpensive and rapid. Since each immuno-assay is sensitive to non-specific reactions, recognition of false positive results is necessary. The most appropriate method for this is to add an inhibitor to the test sample which blocks specifically the paratope of the immunoglobulin. Another general disadvantage of immuno-assays is that only the antigenicity is determined and this may differ from the actual toxicity. Therefore, antibodies should be used that react with the toxic centre(s) of the molecule, which can be accomplished by using well selected monoclonal antibodies.

Animals

Computed tomography-guided precision biopsy combined with metagenomic next-generation sequencing for etiological diagnosis in patients with blood culture-negative systemic infections.

ObjectiveTo evaluate the diagnostic efficacy of computed tomography-guided percutaneous biopsy combined with metagenomic next-generation sequencing in patients with blood culture-negative systemic infections and to assess the clinical impact of using this combined strategy for etiological confirmation and guidance of targeted antimicrobial therapy.MethodsThis single-center retrospective observational cohort study enrolled 78 patients who met the Sepsis-3 consensus criteria for suspected systemic infection and had negative conventional microbiological work-ups (at least two sets of blood cultures) between April 2022 and March 2025. All patients underwent computed tomography-guided biopsy of radiologically identified infectious foci, with specimens processed concurrently for conventional culture and metagenomic next-generation sequencing. Diagnostic performance was benchmarked against the final comprehensive clinical diagnosis, and the influence of metagenomic next-generation sequencing findings on antimicrobial therapy modification was analyzed. Sample size calculation, based on a prior study estimating an metagenomic next-generation sequencing detection rate of 85% (&#x3b1;&#x2009;=&#x2009;0.05, &#x3b2;&#x2009;=&#x2009;0.2), indicated a minimum of 68 cases; accordingly, 78 patients were enrolled.ResultsComputed tomography-guided biopsy was technically successful in all 78 patients (100%). The pathogen detection rate of metagenomic next-generation sequencing (91.0%, 71/78) was significantly higher than that of conventional culture (55.1%, 43/78; p&#x2009;<&#x2009;0.001). Using the final clinical diagnosis as the reference standard, metagenomic next-generation sequencing achieved a sensitivity of 94.7% (95% confidence interval: 86.9-98.5), specificity of 100.0% (95% confidence interval: 29.2-100.0), positive predictive value of 100.0% (95% confidence interval: 94.9-100.0), and negative predictive value of 42.9% (95% confidence interval: 9.9-81.6). Among the 35 culture-negative specimens, metagenomic next-generation sequencing established a definitive microbiological diagnosis in 28 cases (80.0%) and detected polymicrobial infections in 11 cases (14.1% of the cohort). Antimicrobial therapy was rationally adjusted based on metagenomic next-generation sequencing results in 69.2% (54/78) of the patients.ConclusionsThe integration of computed tomography-guided precision biopsy with metagenomic next-generation sequencing offers a highly effective diagnostic approach for blood culture-negative systemic infections. This synergistic strategy improves etiological diagnosis by providing high-yield target specimens that enable comprehensive, unbiased pathogen screening, facilitates differentiation between infectious and non-infectious etiologies, and supplies critical evidence for guiding precision antimicrobial therapy. These findings highlight the growing role of interventional radiology in the contemporary framework of precision infectious disease management.

Humans

Beyond water and soil: Air emerges as a major reservoir of human pathogens.

Assessing the risk of human pathogens in the environment is crucial for controlling the spread of diseases and safeguarding human health. However, conducting a thorough assessment of low-abundance pathogens in highly complex environmental microbial communities remains challenging. This study compiled a comprehensive catalog of 247 human-pathogenic bacterial taxa from global biosafety agencies and identified more than 78 million genome-specific markers (GSMs) from their 17,470 sequenced genomes. Subsequently, we analyzed these pathogens' types, abundance, and diversity within 474 shotgun metagenomic sequences obtained from diverse environmental sources. The results revealed that among the four habitats studied (air, water, soil, and sediment), the detection rate, diversity, and abundance of detectable pathogens in the air all exceeded those in the other three habitats. Air, sediment, and water environments exhibited identical dominant taxa, indicating that these human pathogens may have unique environmental vectors for their transmission or survival. Furthermore, we observed the impact of human activities on the environmental risk posed by these pathogens, where greater amounts of human activities significantly increased the abundance of human pathogenic bacteria, especially in water and air. These findings have remarkable implications for the environmental risk assessment of human pathogens, providing valuable insights into their presence and distribution across different habitats.

Humans

The Next Step: The Role of Metagenomic Next-Generation Sequencing in Microbial Detection of Culture-Negative Cardiovascular Infections.

Cardiovascular infections, including those that involve native and prosthetic heart valves, implantable cardiac devices, mechanical circulatory assist devices, and vascular grafts, are associated with significant morbidity and mortality risks. Optimal management of these complex infections requires pathogen-directed antimicrobial therapy. However, standard culture-based methods often fail to identify causative organisms due to prior antimicrobial use, infections due to fastidious organisms, or biofilm-associated infections. Emerging evidence suggests that microbial cell-free DNA (mcfDNA) and metagenomic testing can enhance pathogen detection, particularly in culture-negative cases. However, their results require careful clinical interpretation, often necessitating input from infectious diseases specialists. In this review, we examine published evidence regarding metagenomic testing for cardiovascular infections and its impact on patient care. We propose a framework for microbiological adjudication of mcfDNA results, introduce standardized definitions for clinical impact assessment, and provide guidance on integrating mcfDNA testing into diagnostic evaluation of patients with culture-negative cardiovascular infections.

Humans

Diagnostic studies of nosocomial diarrhea in children: assessing their use and value.

During a 17-month period (01/11/85-05/31/86) 225 cases of nosocomial diarrhea were identified in a children's hospital. Diarrhea was considered to be nosocomial if it began at least 72 hours after the patient's hospital admission or within 3 days after discharge. One or more routine diagnostic studies for identification of a pathogen were performed in 195 (87%) cases. The most commonly performed test was the bacterial stool culture. None of these samples yielded a bacterial pathogen. The only pathogens detected by routine laboratory studies were rotavirus (61/137 [45%] samples were positive for rotavirus by ELISA) and Clostridium difficile (9/54 [17%] positive for toxin). Of the patients whose tests were positive for rotavirus 56 were younger than 2 years of age, and all were identified in the winter and spring. When multiple stool samples were tested by the diagnostic laboratory, rotavirus was identified in an additional 14 patients whose initial stool samples were negative for rotavirus. All patients whose tests were positive for C. difficile toxin had received antibiotics within the previous 3 months. Ova/parasites were not detected in 53 of the tested stools. We also identified enteric adenovirus in six patients. Viruses were identified in 95 (42%) of the 225 cases of nosocomial gastroenteritis. Nosocomial diarrhea is common in a children's hospital. Rotavirus is the most commonly identified pathogen. Rotavirus testing is valuable in children with nosocomial diarrhea who are younger than 2 years of age, especially in the winter and spring. Multiple samples may be necessary to identify rotavirus. C. difficile toxin assay should be considered for patients who are receiving or who have received antibiotics.(ABSTRACT TRUNCATED AT 250 WORDS)

Cross Infection

Versatile wastewater monitoring of pathogens and antimicrobial resistance enabled by metatranscriptomics and long-read metagenomics.

Widespread interest in the development of population-wide pathogen and antimicrobial resistance (AMR) monitoring has revealed wastewater's microbial footprint as a marker of public health. Near-source wastewater remains a difficult sample type for microbiome analyses but represents a closer link to human health than the downstream products of its treatment. Few studies integrate methods for non-targeted monitoring applications, and critically, current methods cannot connect AMR genes to species, nor resolve full genomes. We address these challenges by developing a pipeline that enables untargeted metagenomics, metatranscriptomics, and novel long-read metagenomics (LRG). We achieve untargeted pathogen detection, limited by highly abundant resident species, while retaining microbial information with near-source sampling. Furthermore, LRG identifies antibiotic resistance gene-containing microbes and enables assembly of culture-independent genomes with previously unreported AMR genes. We establish an integrated approach to broadly monitor pathogens in wastewater, while demonstrating the importance of LRG to illuminate microbial AMR at the species level.

Journal Article

[The place of 67Ga scintigraphy in the primary diagnosis and follow-up evaluation of opportunistic pneumonia in patients with AIDS].

Opportunistic pneumonias are a life-threatening complication in patients with AIDS. Early diagnosis and therapy is necessary to improve prognosis. This study was designed to assess the value of 67Ga scintigraphy in the primary detection and follow-up of these special pneumonias. 67Ga scintigraphy was performed in 40 patients: 10 normal controls and 30 HIV-positive patients with AIDS or AIDS-related complex (ARC). 67Ga scan results were compared with current chest radiographs and the results of pathogen detection. The evaluation of positive scans was based on a quantification of the pulmonary uptake, expressed as a pulmonary/soft-tissue uptake ratio. Only 8/30 patients had a normal scan, 22/30 showed diffuse (13/22) or focal (9/22) increases of pulmonary uptake. In 7/8 patients with normal scans the chest radiograph was negative as well. The one patient with negative scan but positive chest radiograph had pulmonary Kaposi's sarcoma. In 11/22 patients the 67Ga scan and chest radiograph were positive simultaneously. In the other 11/22 patients with positive scans chest radiographs were initially negative but showed pathology in 5 cases within 1-2 weeks. The reason for positive scans in most cases was an opportunistic lung infection; other forms of pneumonia were only observed in two cases. The defined uptake ratio demonstrated to be a highly sensitive parameter for monitoring pneumonia and the effects of therapy in follow-up studies. In conclusion, quantitative 67Ga scintigraphy proved to be a reliable and highly sensitive method for primary detection and follow-up of opportunistic pneumonias in patients with AIDS.

Acquired Immunodeficiency Syndrome

Value of 67gallium scintigraphy in primary diagnosis and follow-up of opportunistic pneumonia in patients with AIDS.

Opportunistic pneumonias are a life-threatening complication in patients with AIDS. Early diagnosis and therapy is necessary to improve the prognosis. This study was designed to assess the value of 67gallium scintigraphy in the primary detection and follow-up of these special pneumonias. 67Gallium scintigraphy was performed in 40 patients: 10 normal controls and 30 HIV-positive patients with AIDS or AIDS-related complex (ARC). 67Gallium scan results were compared with current chest x-rays and the results of pathogen detection. The evaluation of positive scans was based on a quantification of the pulmonary uptake, expressed as a pulmonary/soft tissue uptake ratio. Only 8 of 30 patients had a normal scan, while 22 of 30 showed diffuse (13/22) or focal (9/22) increases of pulmonary uptake. In seven of eight patients with normal scans the chest radiograph was negative as well. The one patient with negative scan but positive chest radiograph had pulmonary Kaposi's sarcoma. In 11 of 22 patients, the 67gallium scan and chest x-ray were positive simultaneously. In the other 11 of 22 patients with positive scans, chest radiographs were initially negative but showed pathology in five cases within 1-2 weeks. The reason for positive scans in most cases was an opportunistic lung infection; other forms of pneumonia were observed only in two cases. The defined uptake ratio was demonstrated to be a highly sensitive parameter for monitoring pneumonia and the effects of therapy in follow-up studies. In conclusion, quantitative 67gallium scintigraphy proved to be a reliable and highly sensitive method for primary detection and follow-up of opportunistic pneumonias in patients with AIDS.

AIDS-Related Complex