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Burkholderia pseudomallei is a Gram-negative soil saprophyte with the potential to cause melioidosis, an opportunistic disease with a high mortality potential. Periodic case reports of melioidosis in or imported from Africa occur in the literature dating back decades. Furthermore, statistical models suggest Western sub-Saharan Africa as a high-risk zone for the presence of B. pseudomallei. A recent case report from the United Kingdom of a returning traveler from Ghana highlights the need for environmental studies in Ghana. We examined 100 soil samples from a rice farm in south-central Ghana. Soil was subjected to selective enrichment culture for B. pseudomallei using threonine-basal salt solution with colistin (TBSS-C50) and erythritol medium, as described in the literature. Bacterial cultures were identified with standard biochemical tests, a rapid antigen detection assay, and real-time PCR specific for B. pseudomallei. Of the 100 soil samples, 55% yielded cultures consistent with B. pseudomallei on Ashdown's agar as well as by capsular polysaccharide antigen production. This is the first confirmatory report of culture-confirmed B. pseudomallei in the environment of Ghana. Our study emphasizes the need for further exploration of the burden of human melioidosis in Ghana. We recommend that local clinicians familiarize themselves with the diagnosis and clinical management of melioidosis, while laboratories develop capacity for the safe isolation and identification of B. pseudomallei. IMPORTANCE We present the first confirmation of the presence of B. pseudomallei in the environment of Ghana. This study will bring attention to a disease with the potential to cause significant morbidity and mortality in Ghana, but which has gone completely unrecognized until this point. Furthermore, this work would encourage local clinicians to familiarize themselves with the diagnosis and clinical management of melioidosis and laboratories to develop capacity for the safe isolation and identification of B. pseudomallei.
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Burkholderia pseudomallei , Melioidosis , Burkholderia pseudomallei/genética , Ghana , Humanos , Melioidosis/diagnóstico , Melioidosis/microbiología , Suelo , Microbiología del SueloRESUMEN
BACKGROUND: Infection with the gram-negative bacterium Burkholderia pseudomallei can result in melioidosis, a life-threatening disease that can be difficult to diagnose. Culture remains the gold standard for diagnosis but requires laboratory resources not available in many endemic regions. A lateral flow immunoassay has shown promise for POC diagnostics but suffers from low sensitivity when used on blood samples. PCR also has low sensitivity on blood, attributed to the low bacterial numbers in blood observed in melioidosis patients, even when bacteraemic. METHODS: A prototype i-STAT cartridge was developed to utilize the monoclonal antibody specific for the capsule of pathogenic Burkholderia species employed on the LFI. The resulting POC assay was evaluated on 414 clinical specimens from Darwin, Australia and Cambodia. RESULTS: The i-STAT assay accurately distinguished Australian blood culture positive melioidosis patients from Australian patients hospitalized with other infections (AUC = 0.91, 95% CI 0.817 - 1.0). We derived an assay cutoff with 76% sensitivity and 94% specificity that correctly classified 88% (n = 74) of the Australian patients. Interestingly, only 46% (6/13) of the culture-positive melioidosis patients in Cambodia were classified correctly. Of great importance however, the assay detected capsule from blood samples for 32% of blood culture negative melioidosis patients in both cohorts and previously undiagnosed melioidosis patients in Cambodia. In addition the assay showed high sensitivity and specificity for urine, pus and sputum. CONCLUSIONS: Diagnostic tools that are not dependent upon the growth kinetics or the levels of bacteremia of B. pseudomallei represent the next-generation of diagnostics and must be pursued further.
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Anticuerpos Monoclonales/inmunología , Burkholderia pseudomallei/inmunología , Inmunoensayo/instrumentación , Melioidosis/diagnóstico , Pruebas en el Punto de Atención , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos Bacterianos/inmunología , Australia , Biomarcadores/sangre , Cultivo de Sangre , Cambodia , Femenino , Humanos , Inmunoensayo/métodos , Masculino , Melioidosis/inmunología , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: Antibiotic resistance is rising at disturbing rates and contributes to the deaths of millions of people yearly. Antibiotic resistant infections disproportionately affect those with immunocompromising conditions, chronic colonization, and frequent antibiotic use such as transplant patients or those with cystic fibrosis. However, clinicians lack the diagnostic tools to confidently diagnose and treat infections, leading to widespread use of empiric broad spectrum antimicrobials, often for prolonged duration. CASE PRESENTATION: A 22 year-old Caucasian female with cystic fibrosis received a bilateral orthotopic lung transplantation 5 months prior to the index hospitalization. She underwent routine surveillance bronchoscopy and was admitted for post-procedure fever. A clear cause of infection was not identified by routine methods. Imaging and bronchoscopic lung biopsy did not identify an infectious agent or rejection. She was treated with a prolonged course of antimicrobials targeting known colonizing organisms from prior bronchoalveolar lavage cultures (Pseudomonas, Staphylococcus aureus, and Aspergillus). However, we identified Stenotrophomonas maltophilia in two independent whole blood samples using direct-pathogen sequencing, which was not identified by other methods. CONCLUSIONS: This case represents a common clinical conundrum: identification of infection in a high-risk, complex patient. Here, direct-pathogen sequencing identified a pathogen that would not otherwise have been identified by common techniques. Had results been clinically available, treatment could have been customized, avoiding a prolonged course of broad spectrum antimicrobials that would only exacerbate resistance. Direct-pathogen sequencing is poised to fill a diagnostic gap for pathogen identification, allowing early identification and customization of treatment in a culture-independent, pathogen-agnostic manner.
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Broncoscopía/efectos adversos , Fiebre/etiología , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/etiología , Secuenciación de Nucleótidos de Alto Rendimiento , Análisis de Secuencia de ARN , Stenotrophomonas maltophilia/genética , Antibacterianos/uso terapéutico , Lavado Broncoalveolar , Toma de Decisiones Clínicas , Fibrosis Quística/cirugía , Farmacorresistencia Bacteriana , Femenino , Fiebre/tratamiento farmacológico , Humanos , Trasplante de Pulmón , Pseudomonas/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificación , Resultado del Tratamiento , Adulto JovenRESUMEN
Infection with either Rickettsia prowazekii or Orientia tsutsugamushi is common, yet diagnostic capabilities are limited due to the short window for positive identification. Until now, although targeted enrichment had been applied to increase sensitivity of sequencing-based detection for various microorganisms, it had not been applied to sequencing of R. prowazekii in clinical samples. Additionally, hybridization-based targeted enrichment strategies had only scarcely been applied to qPCR of any pathogens in clinical samples. Therefore, we tested a targeted enrichment technique as a proof of concept and found that it dramatically reduced the limits of detection of these organisms by both qPCR and high throughput sequencing. The enrichment methodology was first tested in contrived clinical samples with known spiked-in concentrations of R. prowazekii and O. tsutsugamushi DNA. This method was also evaluated using clinical samples, resulting in the simultaneous identification and characterization of O. tsutsugamushi directly from clinical specimens taken from sepsis patients. We demonstrated that the targeted enrichment technique is helpful by lowering the limit of detection, not only when applied to sequencing, but also when applied to qPCR, suggesting the technique could be applied more broadly to include other assays and/or microbes for which there are limited diagnostic or detection modalities.
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This study presented the detection and quantification of capsular polysaccharide (CPS) as a biomarker for the diagnosis of melioidosis. After successfully screening four monoclonal antibodies (mAbs) previously determined to bind CPS molecules, the team developed a portable electrochemical immunosensor based on antibody-antigen interactions. The biosensor was able to detect CPS with a wide detection range from 0.1pg/mL to 1 µg/mL. The developed biosensor achieved high sensitivity for the detection of CPS spiked into both urine and serum. The developed assay platform was successfully programmed into a Windows app, and the sensor performance was evaluated with different spiked concentrations. The rapid electro-analytical device (READ) sensor showed great unprecedented sensitivity for the detection of CPS molecules in both serum and urine, and results were cross-validated with ELISA methods.
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Burkholderia pseudomallei , Técnicas Electroquímicas , Melioidosis , Polisacáridos Bacterianos , Burkholderia pseudomallei/inmunología , Melioidosis/diagnóstico , Melioidosis/microbiología , Melioidosis/orina , Humanos , Técnicas Electroquímicas/métodos , Inmunoensayo/métodos , Polisacáridos Bacterianos/inmunología , Técnicas Biosensibles/métodos , Anticuerpos Monoclonales/inmunología , Cápsulas Bacterianas/inmunología , Anticuerpos Antibacterianos/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Biomarcadores/sangre , Biomarcadores/orinaRESUMEN
BACKGROUND: Sepsis from infection is a global health priority and clinical trials have failed to deliver effective therapeutic interventions. To address complicating heterogeneity in sepsis pathobiology, and improve outcomes, promising precision medicine approaches are helping identify disease endotypes, however, they require a more complete definition of sepsis subgroups. METHODS: Here, we use RNA sequencing from peripheral blood to interrogate the host response to sepsis from participants in a global observational study carried out in West Africa, Southeast Asia, and North America (N = 494). RESULTS: We identify four sepsis subtypes differentiated by 28-day mortality. A low mortality immunocompetent group is specified by features that describe the adaptive immune system. In contrast, the three high mortality groups show elevated clinical severity consistent with multiple organ dysfunction. The immunosuppressed group members show signs of a dysfunctional immune response, the acute-inflammation group is set apart by molecular features of the innate immune response, while the immunometabolic group is characterized by metabolic pathways such as heme biosynthesis. CONCLUSIONS: Our analysis reveals details of molecular endotypes in sepsis that support immunotherapeutic interventions and identifies biomarkers that predict outcomes in these groups.
Sepsis is a life-threatening multi-organ failure caused by the body's immune response to infection. Clinical symptoms of sepsis vary from one person to another likely due to differences in host factors, infecting pathogen, and comorbidities. This difference in clinical symptoms may contribute to the lack of effective interventions for sepsis. Therefore, approaches tailored to targeting groups of patients who present similarly are of great interest. This study analysed a large group of sepsis patients with diverse symptoms using laboratory markers and mathematical analysis. We report four patient groups that differ by risk of death and immune response profile. Targeting these defined groups with tailored interventions presents an exciting opportunity to improve the health outcomes of patients with sepsis.
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Melioidosis is a potentially severe disease caused by the gram-negative soil-dwelling bacterium called Burkholderia pseudomallei. The true breadth of the distribution of this tropical pathogen is starting to emerge with environmental and clinical isolates frequently characterized in new countries and regions. Even so, isolates, clinical cases, and genetic data from the continent of Africa remain scant. We previously confirmed the presence of B. pseudomallei in the environment of Ghana, unmasking a new area of endemicity for this pathogen. Here, we describe the genetic characteristics of isolates obtained from that environmental survey. Twenty-one isolates were subjected to whole genome sequencing and found to represent three discrete sequence types (ST), one of which was novel, and designated ST2058. Phylogenetic analysis places this novel isolate within a B. pseudomallei clade that includes genomes derived from the Americas, although it is closely related to a sub-clade that includes isolates from Africa. Importantly, phenotypic characterization demonstrates common features including API 20NE profiles and B. pseudomallei CPS to support existing diagnostics, and susceptibility to standard of care antibiotics often used in the clinical management of melioidosis. These findings add to our knowledge about the presence and distribution of B. pseudomallei in Africa and represent the first published genomes out of Ghana.
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Our limited understanding of the pathophysiological mechanisms that operate during sepsis is an obstacle to rational treatment and clinical trial design. There is a critical lack of data from low- and middle-income countries where the sepsis burden is increased which inhibits generalized strategies for therapeutic intervention. Here we perform RNA sequencing of whole blood to investigate longitudinal host response to sepsis in a Ghanaian cohort. Data dimensional reduction reveals dynamic gene expression patterns that describe cell type-specific molecular phenotypes including a dysregulated myeloid compartment shared between sepsis and COVID-19. The gene expression signatures reported here define a landscape of host response to sepsis that supports interventions via targeting immunophenotypes to improve outcomes.
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COVID-19 , Fenotipo , Sepsis , Transcriptoma , Humanos , Sepsis/genética , Sepsis/sangre , Sepsis/inmunología , COVID-19/inmunología , COVID-19/genética , COVID-19/sangre , COVID-19/virología , Ghana/epidemiología , Masculino , Estudios de Cohortes , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Femenino , Adulto , Persona de Mediana Edad , Perfilación de la Expresión Génica , Análisis de Secuencia de ARNRESUMEN
PURPOSE: A rapid immune response is required to prevent death from Anthrax, caused by Bacillus anthracis. METHOD: We formulated a vaccine carrier comprised of acetalated dextran microparticles encapsulating recombinant protective antigen (rPA) and resiquimod (a toll-like receptor 7/8 agonist). RESULTS: We were able to protect against triplicate lethal challenge by vaccinating twice (Days 0, 7) and then aggressively challenging on Days 14, 21, 28. A significantly higher level of antibodies was generated by day 14 with the encapsulated group compared to the conventional rPA and alum group. Antibodies produced by the co-encapsulated group were only weakly-neutralizing in toxin neutralization; however, survival was not dependent on toxin neutralization, as all vaccine formulations survived all challenges except control groups. Post-mortem culture swabs taken from the hearts of vaccinated groups that did not produce significant neutralizing titers failed to grow B. anthracis. CONCLUSIONS: Results indicate that protective antibodies are not required for rapid protection; indeed, cytokine results indicate that T cell protection may play a role in protection from anthrax. We report the first instance of use of a particulate carrier to generate a rapid protective immunity against anthrax.
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Vacunas contra el Carbunco/uso terapéutico , Carbunco/prevención & control , Bacillus anthracis/inmunología , Dextranos/química , Portadores de Fármacos/química , Acetilación , Animales , Carbunco/inmunología , Carbunco/microbiología , Vacunas contra el Carbunco/administración & dosificación , Vacunas contra el Carbunco/inmunología , Formación de Anticuerpos , Antígenos Bacterianos/administración & dosificación , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/uso terapéutico , Toxinas Bacterianas/administración & dosificación , Toxinas Bacterianas/inmunología , Toxinas Bacterianas/uso terapéutico , Imidazoles/administración & dosificación , Imidazoles/uso terapéutico , Ratones , Receptores Toll-Like/agonistas , Vacunación , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/uso terapéuticoRESUMEN
On an annual basis, approximately 2,500 U.S. Marines and Sailors deploy to Australia on 6-month training rotations. Active duty personnel are generally immunologically naïve to pathogens endemic to tropical Australia, a vulnerability that could significantly impact medical readiness. To estimate risk, we screened 628 post-deployment serum samples by ELISA for serological evidence of infection with Ross River virus (RRV), a mosquito-borne alphavirus endemic to tropical Australia. Samples that tested above the negative cutoff value were paired with their pre-deployment samples to identify deployment-related seroconversion. These paired samples were further investigated with a live virus neutralization assay to assess specificity. There was a single RRV seroconversion and 49 false-positive results. In the context of these analyses (i.e., limited sample numbers collected between the months of March and October), we assess the RRV risk to MRFD as low and encourage strategies such as avoiding and preventing mosquito bites to mitigate the existing risk over widespread vaccination programs, if an FDA-approved vaccine becomes available. The Panbio RRV ELISA lacks the specificity to draw conclusions based on seropositivity from large-scale surveys of U.S. personnel.
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Infecciones por Alphavirus , Personal Militar , Animales , Humanos , Australia/epidemiología , Infecciones por Alphavirus/epidemiología , Virus del Río Ross , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
OBJECTIVES: We evaluated the performance of commonly used sepsis screening tools across prospective sepsis cohorts in the USA, Cambodia and Ghana. DESIGN: Prospective cohort studies. SETTING AND PARTICIPANTS: From 2014 to 2021, participants with two or more SIRS (Systemic Inflammatory Response Syndrome) criteria and suspected infection were enrolled in emergency departments and medical wards at hospitals in Cambodia and Ghana and hospitalised participants with suspected infection were enrolled in the USA. Cox proportional hazards regression was performed, and Harrell's C-statistic calculated to determine 28-day mortality prediction performance of the quick Sequential Organ Failure Assessment (qSOFA) score ≥2, SIRS score ≥3, National Early Warning Score (NEWS) ≥5, Modified Early Warning Score (MEWS) ≥5 or Universal Vital Assessment (UVA) score ≥2. Screening tools were compared with baseline risk (age and sex) with the Wald test. RESULTS: The cohorts included 567 participants (42.9% women) including 187 participants from Kumasi, Ghana, 200 participants from Takeo, Cambodia and 180 participants from Durham, North Carolina in the USA. The pooled mortality was 16.4% at 28 days. The mortality prediction accuracy increased from baseline risk with the MEWS (C-statistic: 0.63, 95% CI 0.58 to 0.68; p=0.002), NEWS (C-statistic: 0.68; 95% CI 0.64 to 0.73; p<0.001), qSOFA (C-statistic: 0.70, 95% CI 0.64 to 0.75; p<0.001), UVA score (C-statistic: 0.73, 95% CI 0.69 to 0.78; p<0.001), but not with SIRS (0.60; 95% CI 0.54 to 0.65; p=0.13). Within individual cohorts, only the UVA score in Ghana performed better than baseline risk (C-statistic: 0.77; 95% CI 0.71 to 0.83; p<0.001). CONCLUSIONS: Among the cohorts, MEWS, NEWS, qSOFA and UVA scores performed better than baseline risk, largely driven by accuracy improvements in Ghana, while SIRS scores did not improve prognostication accuracy. Prognostication scores should be validated within the target population prior to clinical use.
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Sepsis , Adulto , Femenino , Humanos , Masculino , Estudios Prospectivos , Sepsis/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Cambodia , Estudios de CohortesRESUMEN
Diagnostic limitations challenge management of clinically indistinguishable acute infectious illness globally. Gene expression classification models show great promise distinguishing causes of fever. We generated transcriptional data for a 294-participant (USA, Sri Lanka) discovery cohort with adjudicated viral or bacterial infections of diverse etiology or non-infectious disease mimics. We then derived and cross-validated gene expression classifiers including: 1) a single model to distinguish bacterial vs. viral (Global Fever-Bacterial/Viral [GF-B/V]) and 2) a two-model system to discriminate bacterial and viral in the context of noninfection (Global Fever-Bacterial/Viral/Non-infectious [GF-B/V/N]). We then translated to a multiplex RT-PCR assay and independent validation involved 101 participants (USA, Sri Lanka, Australia, Cambodia, Tanzania). The GF-B/V model discriminated bacterial from viral infection in the discovery cohort an area under the receiver operator curve (AUROC) of 0.93. Validation in an independent cohort demonstrated the GF-B/V model had an AUROC of 0.84 (95% CI 0.76-0.90) with overall accuracy of 81.6% (95% CI 72.7-88.5). Performance did not vary with age, demographics, or site. Host transcriptional response diagnostics distinguish bacterial and viral illness across global sites with diverse endemic pathogens.
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Infecciones Bacterianas , Virosis , Humanos , Virosis/diagnóstico , Virosis/genética , Biomarcadores , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/genética , Cambodia , AustraliaRESUMEN
The use of positive blood culture bottles for direct disk diffusion susceptibility testing (dDD), together with chromogenic culture limited to groups of pathogens for antimicrobial susceptibility testing interpretation may provide a means for laboratories-in-development to introduce rapid abbreviated blood culture testing. We assessed the performance of dDD on Chromatic MH agar using contrived positive blood culture bottles and compared findings with current standard practice. Furthermore, we characterized the growth of 24 bacterial and 3 yeast species on Chromatic MH agar with the aid of rapid spot tests for same-day identification. The coefficient of variation for reproducibility of dDD of four reference strains in 4 to 10 replicates (238 data points) ranged from 0% to 16.3%. Together with an additional 10 challenge isolates, the overall categorical agreement was 91.7% (351 data points). The following bacteria were readily identifiable: cream/white Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus pyogenes; turquoise Streptococcus agalactiae, enterococci, Listeria monocytogenes; mauve Escherichia coli, Shigella sonnei, Citrobacter freundii; dark-blue Klebsiella and Enterobacter; green Pseudomonas aeruginosa; and brown Proteus. Clear colonies were seen with Salmonella, Acinetobacter, Burkholderia, and Yersinia enterocolitica (turns pink). Our study suggests that Chromatic MH for dDD may show promise as a rapid, clinically useful presumptive method for overnight simultaneous identification and antimicrobial susceptibility testing. However, there is a need to optimize the medium formulation to allow the recovery of Streptococcus pneumoniae and Haemophilus influenzae.
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Antiinfecciosos , Cultivo de Sangre , Humanos , Agar , Identificación Social , Reproducibilidad de los Resultados , Streptococcus pyogenes , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacologíaRESUMEN
Early in the pandemic, in March of 2020, an outbreak of COVID-19 occurred aboard the aircraft carrier USS Theodore Roosevelt (CVN-71), during deployment in the Western Pacific. Out of the crew of 4,779 personnel, 1,331 service members were suspected or confirmed to be infected with SARS-CoV-2. The demographic, epidemiologic, and laboratory findings of service members from subsequent investigations have characterized the outbreak as widespread transmission of virus with relatively mild symptoms and asymptomatic infection among mostly young healthy adults. At the time, there was no available vaccination against COVID-19 and there was very limited knowledge regarding SARS-CoV-2 mutation, dispersal, and transmission patterns among service members in a shipboard environment. Since that time, other shipboard outbreaks from which data can be extracted have occurred, but these later shipboard outbreaks have occurred largely in settings where the majority of the crew were vaccinated, thereby limiting spread of the virus, shortening duration of the outbreaks, and minimizing evolution of the virus within those close quarters settings. On the other hand, since the outbreak on the CVN-71 occurred prior to widespread vaccination, it continued over the course of roughly two months, infecting more than 25% of the crew. In order to better understand genetic variability and potential transmission dynamics of COVID-19 in a shipboard environment of immunologically naïve, healthy individuals, we performed whole-genome sequencing and virus culture from eighteen COVID-19-positive swabs collected over the course of one week. Using the unique variants identified in those genomes, we detected seven discrete groups of individuals within the population aboard CVN-71 infected with viruses of distinct genomic signature. This is in stark contrast to a recent outbreak aboard another U.S. Navy ship with >98% vaccinated crew after a port visit in Reykjavik, Iceland, where the outbreak lasted only approximately 2âweeks and the virus was clonal. Taken together, these results demonstrate the utility of sequencing from complex clinical samples for molecular epidemiology and they also suggest that a high rate of vaccination among a population in close communities may greatly reduce spread, thereby restricting evolution of the virus.
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BACKGROUND: Venous phlebotomy performed by trained personnel is critical for patient diagnosis and monitoring of chronic disease, but has limitations in resource-constrained settings, and represents an infection control challenge during outbreaks. Self-collection devices have the potential to shift phlebotomy closer to the point of care, supporting telemedicine strategies and virtual clinical trials. Here we assess a capillary blood micro-sampling device, the Tasso Serum Separator Tube (SST), for measuring blood protein levels in healthy subjects and non-hospitalized COVID-19 patients. METHODS: 57 healthy controls and 56 participants with mild/moderate COVID-19 were recruited at two U.S. military healthcare facilities. Healthy controls donated Tasso SST capillary serum, venous plasma and venous serum samples at multiple time points, while COVID-19 patients donated a single Tasso SST serum sample at enrolment. Concentrations of 17 protein inflammatory biomarkers were measured in all biospecimens by Ella multi-analyte immune-assay. RESULTS: Tasso SST serum protein measurements in healthy control subjects were highly reproducible, but their agreements with matched venous samples varied. Most of the selected proteins, including CRP, Ferritin, IL-6 and PCT, were well-correlated between Tasso SST and venous serum with little sample type bias, but concentrations of D-dimer, IL-1B and IL-1Ra were not. Self-collection at home with delayed sample processing was associated with significant concentrations differences for several analytes compared to supervised, in-clinic collection with rapid processing. Finally, Tasso SST serum protein concentrations were significantly elevated in in non-hospitalized COVID-19 patients compared with healthy controls. CONCLUSIONS: Self-collection of capillary blood with micro-sampling devices provides an attractive alternative to routine phlebotomy. However, concentrations of certain analytes may differ significantly from those in venous samples, and factors including user proficiency, temperature control and time lags between specimen collection and processing need to be considered for their effect on sample quality and reproducibility.
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COVID-19 , Proteínas Sanguíneas , Recolección de Muestras de Sangre , COVID-19/diagnóstico , Voluntarios Sanos , Humanos , Reproducibilidad de los Resultados , Manejo de EspecímenesRESUMEN
The associations between clinical phenotypes of coronavirus disease 2019 (COVID-19) and the host inflammatory response during the transition from peak illness to convalescence are not yet well understood. Blood plasma samples were collected from 129 adult SARS-CoV-2 positive inpatient and outpatient participants between April 2020 and January 2021, in a multi-center prospective cohort study at 8 military hospitals across the United States. Plasma inflammatory protein biomarkers were measured in samples from 15 to 28 days post symptom onset. Topological Data Analysis (TDA) was used to identify patterns of inflammation, and associations with peak severity (outpatient, hospitalized, ICU admission or death), Charlson Comorbidity Index (CCI), and body mass index (BMI) were evaluated using logistic regression. The study population (n = 129, 33.3% female, median 41.3 years of age) included 77 outpatient, 31 inpatient, 16 ICU-level, and 5 fatal cases. Three distinct inflammatory biomarker clusters were identified and were associated with significant differences in peak disease severity (p < 0.001), age (p < 0.001), BMI (p < 0.001), and CCI (p = 0.001). Host-biomarker profiles stratified a heterogeneous population of COVID-19 patients during the transition from peak illness to convalescence, and these distinct inflammatory patterns were associated with comorbid disease and severe illness due to COVID-19.
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COVID-19 , Humanos , Femenino , Estados Unidos/epidemiología , Masculino , SARS-CoV-2 , Estudios Prospectivos , Convalecencia , Biomarcadores , Fenotipo , Índice de Severidad de la Enfermedad , HospitalizaciónRESUMEN
BACKGROUND: The relationship between postvaccination symptoms and strength of antibody responses is unclear. The goal of this study was to determine whether adverse effects caused by vaccination with the Pfizer/BioNTech BNT162b2 vaccine are associated with the magnitude of vaccine-induced antibody levels. METHODS: We conducted a single-center, observational cohort study consisting of generally healthy adult participants that were not severely immunocompromised, had no history of coronavirus disease 2019, and were seronegative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein before vaccination. Severity of vaccine-associated symptoms was obtained through participant-completed questionnaires. Testing for immunoglobulin G antibodies against SARS-CoV-2 spike protein and receptor-binding domain was conducted using microsphere-based multiplex immunoassays performed on serum samples collected at monthly visits. Neutralizing antibody titers were determined by microneutralization assays. RESULTS: Two hundred six participants were evaluated (69.4% female, median age 41.5 years old). We found no correlation between vaccine-associated symptom severity scores and vaccine-induced antibody titers 1 month after vaccination. We also observed that (1) postvaccination symptoms were inversely correlated with age and weight and more common in women, (2) systemic symptoms were more frequent after the second vaccination, (3) high symptom scores after first vaccination were predictive of high symptom scores after second vaccination, and (4) older age was associated with lower titers. CONCLUSIONS: Lack of postvaccination symptoms after receipt of the BNT162b2 vaccine does not equate to lack of vaccine-induced antibodies 1 month after vaccination.
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The implementation of endotype-driven effective intervention strategies is now considered as an essential component for sepsis management. Rapid screening and frequent monitoring of immune responses are critical for evidence-based informed decisions in the early hours of patient arrival. Current technologies focus on pathogen identification that lack rapid testing of the patient immune response, impeding clinicians from providing appropriate sepsis treatment. Herein, we demonstrate a first-of-its-kind novel point-of-care device that uses a unique approach by directly monitoring a panel of five cytokine biomarkers (IL-6, IL-8, IL-10, TRAIL & IP-10), that is attributed as a sign of the body's host immune response to sepsis. The developed point-of-care device encompasses a disposable sensor cartridge attached to an electrochemical reader. High sensitivity is achieved owing to the unique sensor design with an array of nanofilm semiconducting/metal electrode interface, functionalized with specific capture probes to measure target biomarkers simultaneously using non-faradaic electrochemical impedance spectroscopy. The sensor has a detection limit of ~1 pg/mL and provides results in less than five minutes from a single drop of undiluted plasma sample. Furthermore, the sensor demonstrates an excellent correlation (Pearson's r > 0.90) with the reference method for a total n = 40 clinical samples, and the sensor's performance is ~30 times faster compared to the standard reference technique. We have demonstrated the sensor's effectiveness to enhance diagnosis with a mechanistic biomarker-guided approach that can help disease endotypying for effective clinical management of sepsis at the patient bedside.
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Técnicas Biosensibles , Sepsis , Citocinas , Espectroscopía Dieléctrica , Técnicas Electroquímicas , Humanos , Sistemas de Atención de Punto , Sepsis/diagnósticoRESUMEN
Sepsis is a life-threatening condition and understanding the disease pathophysiology through the use of host immune response biomarkers is critical for patient stratification. Lack of accurate sepsis endotyping impedes clinicians from making timely decisions alongside insufficiencies in appropriate sepsis management. This work aims to demonstrate the potential feasibility of a data-driven validation model for supporting clinical decisions to predict sepsis host-immune response. Herein, we used a machine learning approach to determine the predictive potential of identifying sepsis host immune response for patient stratification by combining multiple biomarker measurements from a single plasma sample. Results were obtained using the following cytokines and chemokines IL-6, IL-8, IL-10, IP-10 and TRAIL where the test dataset was 70%. Supervised machine learning algorithm naïve Bayes and decision tree algorithm showed good accuracy of 96.64% and 94.64%. These promising findings indicate the proposed AI approach could be a valuable testing resource for promoting clinical decision making.
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Algoritmos , Biomarcadores/análisis , Aprendizaje Automático , Sepsis/diagnóstico , Teorema de Bayes , Estudios de Casos y Controles , Toma de Decisiones Clínicas , Humanos , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: In 2012, US Marines and Sailors began annual deployments to Australia to participate in joint training exercises with the Australian Defence Force and other partners in the region. During their training, US service members are exposed to a variety of infectious disease threats not normally encountered by American citizens. This paper describes a cohort of US Marines and Sailors enrolled during five rotations to Australia between 2016 and 2020. PARTICIPANTS: Study participation is strictly voluntary. Group informational sessions are held prior to deployment to describe the study structure and goals, as well as the infectious disease threats that participants may encounter while in Australia. All participants provided written informed consent. Consented participants complete a pre-deployment questionnaire to collect data including basic demographic information, military occupational specialty, travel history, family history, basic health status and personal habits such as alcohol consumption. Blood is collected for serum, plasma and peripheral blood mononuclear cells (PBMC) processing. Data and specimen collection is repeated up to three times: before, during and after deployment. FINDINGS TO DATE: From the five rotations that comprised the 2016-2020 Marine Rotational Force-Darwin, we enrolled 1289 volunteers. Enrolments during this period were overwhelmingly white male under the age of 24 years. Most of the enrollees were junior enlisted and non-commissioned officers, with a smaller number of staff non-commissioned officers and commissioned officers, and minimal warrant officers. Over half of the enrollees had occupational specialty designations for infantry. FUTURE PLANS: In the future, we will screen samples for serological evidence of infection with Burkholderia pseudomallei, Coxiella burnetii, Ross River virus, SARS-CoV-2 and other operationally relevant pathogens endemic in Australia. Antigenic stimulation assays will be performed on PBMCs collected from seropositive individuals to characterise the immune response to these infections in this healthy American population.