Transplantation

BackgroundThe effects of Banff histological diagnoses on kidney transplant outcome have been well characterized. However, repeated observation of such histological injury across multiple biopsies in kidney transplant recipients remains insufficiently explored. MethodsIn an observational cohort (N=1819 transplantations with 5736 post-transplant biopsies, recurrent event survival models quantified transitions between diagnoses of T-cell mediated rejection (TCMR), antibody-mediated rejection (AMR), DSA-negative C4d-negative microvascular inflammation (MVIDSA-/C4d-), BK polyomavirus nephropathy (BKPyVAN), borderline TCMR (bTCMR), and probable AMR (pAMR), revealing patterns in the disease trajectories. In two observational cohorts (N=1818 transplantations with 5732 biopsies, N=853 transplantations with 975 biopsies), time-dependent cumulative covariates were constructed for TCMR, AMR, MVIDSA-/C4d- and BKPyVAN, enabling estimation of associations of repeated diagnoses with graft failure using multivariable cause-specific Cox models. ResultsThe incidence rate of a diagnosis was most strongly associated with earlier diagnosis of the same type, but associations between different types of diagnoses also occurred. The hazard of kidney graft failure was significantly increased by repeated observation of TCMR in multiple biopsies (HR 7.97, 95% CI 4.94 - 12.86), as well as by repeated AMR (HR 6.19, 95% CI 3.15 - 12.17), repeated MVIDSA-/C4d- (HR 4.53, 95% CI 2.15-9.54) and repeated BKPyVAN (HR 10.90, 95% CI 5.83 - 20.35). The hazard of graft failure was increased more after repeated diagnoses in transplants than after first diagnoses. The effects of repeated TCMR and repeated AMR remained significant even when observed in protocol biopsies in the absence of graft dysfunction. Repeated observation of BKPyVAN was the most detrimental of all diagnoses when observed in indication biopsies, but it was the least harmful when observed in protocol biopsies. ConclusionIncidence of Banff histological diagnoses appears to be affected by earlier diagnoses, especially those of the same type. These repeated observations of a specific diagnosis have an additional effect on the hazard of graft failure, underscoring a critical unmet need for adequate treatment strategies for these recurrent or persistent injury processes. Lay summaryIn two observational cohorts of 1819 and 750 kidney transplant recipients, kidney transplant biopsies were taken at multiple time points after transplantation. Based on the Banff classification for transplant pathology, various post-transplant diseases were diagnosed, often at more than one time point during follow-up. We assessed patterns in the occurrence of diagnoses over time, and related these diagnoses to survival of the kidney grafts using survival models with time-dependent cumulative diagnoses. We found that repeated observation of the same diagnosis was much more common than consecutive observations of different diagnoses. Repeated diagnoses of tissue injury also decreased kidney graft survival more compared to single diagnoses. This indicates that treatment options for patients with repeated or persistent diagnoses are currently inadequate and novel strategies are needed.

BackgroundIn lung transplantation, de novo immunodominant donor-specific anti-HLA antibodies recognizing HLA-DQ antigens (dn-iDSA-DQ) are predominant and can induce chronic lung allograft dysfunction (CLAD). We previously developed a method to measure the active concentration of dn-iDSA-DQ. We aimed to determine whether this new quantitative biomarker is associated with transplantation outcomes. MethodsThis retrospective multicentre cohort study included 90 lung transplant recipients (LTRs) developing dn-iDSA-DQ, evidenced through single antigen flow beads (SAFB) follow-up. We measured the active concentration of dn-iDSA-DQ at the time of their first detection (T0) for all LTRs, and within the 2 years after DSA detection, whenever possible. SAFB dn-iDSA-DQ characteristics and clinical data were retrieved up to 5 years after DSA detection. ResultsWe tested 184 sera with SPR (n=90 at T0, n=94 within the 2 years after DSA detection), among which 63 (34.4%) had a quantifiable concentration of the dn-iDSA-DQ ([&ge;]0.3 nM). The median SAFB mean fluorescence intensity (MFI) of the dn-iDSA-DQ with a concentration [&ge;]0.3 nM was higher (p<0.0001), yet the correlation between SAFB MFI and active concentration was low (r=0.758, p<0.0001). In multivariate analysis, a concentration of the dn-iDSA-DQ [&ge;]0.3 nM at T0 was independently associated with a lower 2-year CLAD-free survival (HR 2.06, p=0.02). A concentration of the dn-iDSA-DQ [&ge;]0.3 nM within the 2 years from DSA detection was associated with a lower graft survival in univariate analysis. ConclusionsActive concentration of dn-iDSA-DQ appears as a valuable biomarker to identify pathogenic DSA at their first detection because of its association with CLAD.

BackgroundIron metabolism disorder is highly prevalent before and after heart transplantation (HTx). The impact of pretransplant and posttransplant iron disorder on posttransplant outcomes is unclear. ObjectivePretransplant serum levels of key regulator proteins of iron metabolism (hepcidin, interleukin-6, erythroferrone) were tested for prediction of the composite outcome 1-year posttransplant all-cause mortality (ACM) or [&ge;]moderate acute cellular rejection (ACR). Furthermore, serum levels of these proteins were measured at 1-year posttransplant to explore their posttransplant course and association with ACR. ResultsIn a multicenter cohort including 276 consecutive HTx recipients, patients with or without outcome (n=118/158, respectively) did not differ for pretransplant demographics, mismatch of donor/recipient sex, mismatch of HLA epitopes, and hepcidin or interleukin-6 levels. However, pretransplant erythroferrone levels were higher (1.40 vs. 1.19 ng/mL; p=0.013) and hemoglobin levels were lower (124.5 vs. 127 g/L; p=0.004) among patients with the composite outcome. Pretransplant erythroferrone levels >2.25 ng/ml (4th-quartile) were significantly associated with the composite outcome in multivariable analysis (OR 2.17; 95% CI 1.19-3.94, p=0.011; reference: 1st-3rd quartiles). In adjusted predicted proportions analysis, the incidence of the composite outcome was higher in 4th-quartile patients when compared to 1-3rd -quartiles patients (58.0 vs. 37.7%; p=0.003). At 1-year posttransplant, 80.4% of patients with pretransplant erythroferrone levels >2.25 ng/ml remained high; 88.4% of patients with pretransplant erythroferrone levels [&le;]2.25 ng/ml had high levels posttransplant. In 1-year survivors with high erythroferrone levels and [&ge;]moderate ACR during the first postoperative year, the ratio of the opponent regulators of hepcidin gene expression, erythroferrone to interleukin-6, was higher when compared to those without ACR (1.18 vs. 0.41; p=0.016). Hepcidin levels were not different between these two subgroups indicating disproportionate ERFE increase. ConclusionHigh pretransplant erythroferrone levels predict the composite posttransplant outcome 1-year ACM and ACR. Disproportionately high posttransplant erythroferrone levels are related with [&ge;]moderate acute cellular rejection.

Background & AimsPerihilar cholangiocarcinoma is an aggressive malignancy with clinical heterogeneity and poor long-term outcomes after resection. Current prognostic assessment relies mainly on anatomical staging and pathological features, which incompletely capture the entire postoperative risk. We aimed to determine whether integrative analysis of clinical, surgical, pathological and tumor genomic data could improve time-resolved, individualized recurrence-risk prediction after curative-intent resection. MethodsWe performed a multicenter retrospective study including patients undergoing curative-intent resection for perihilar cholangiocarcinoma in ten Spanish hospitals (2003-2023). Overall and disease-free survival were analyzed using Cox models. Outcome-agnostic clinical phenotypes were derived by unsupervised clustering of clinical and surgical features. Targeted tumor sequencing of cancer-associated hotspot regions and selected genes was performed. Prognostic models integrating clinical and genomic data were trained and evaluated in independent training/test sets using penalized and latent-component Cox frameworks, with time dependent discrimination. ResultsThe final cohort comprised 142 patients, with a median follow-up of 26.4 months. Recurrence occurred in 61.3% of patients, and 53.5% died during follow-up. Classical pathological factors were strongly associated with survival and recurrence. Unsupervised outcome-agnostic clustering identified three reproducible clinical phenotypes with markedly different recurrence patterns and survival, only partially explained by anatomical staging. Integrative clinical-genomic modelling further improved recurrence-risk prediction, achieving high discrimination in independent validation (time-dependent AUC [~]0.8). Moreover, the integrative model assigned higher risk over time to patients who relapsed. Patients combining unfavorable clinical phenotype with high genomic-derived risk exhibited a high probability of early recurrence. ConclusionsIntegrated clinical phenotyping and targeted genomic profiling substantially refine recurrence-risk stratification after resection of perihilar cholangiocarcinoma beyond anatomical staging alone. This provides a pragmatic framework for risk-adapted postoperative surveillance and therapeutic decision-making. Impact and ImplicationsThis study provides a data-driven framework integrating clinical, surgical and targeted genomic information to refine prognostic stratification after resection of perihilar cholangiocarcinoma, addressing the limitations of anatomy-based staging in capturing biological heterogeneity. The results are particularly relevant for clinicians managing postoperative surveillance and adjuvant strategies, as they identify patient subgroups with markedly different risks of early recurrence despite similar conventional staging. In practical terms, the combination of unsupervised clinical phenotyping and a targeted, biologically informed genomic panel could support risk-adapted follow-up intensity, selection for adjuvant or experimental therapies, and enrolment into clinical trials. While prospective validation is required before routine implementation, this approach offers a feasible and interpretable pathway toward precision postoperative management in a highly aggressive malignancy.

Vaccination frequently elicits suboptimal immunogenicity in organ transplant recipients, particularly those on long-term immunosuppressive therapy, highlighting the need for improved understanding of immunosuppression mechanisms and optimized vaccination strategies. This study enrolled a cohort of 132 individuals and observed significantly lower antibody levels in kidney transplant recipients (KTRs) compared to non-transplant controls (non-KTRs). Antibody levels were inversely associated with both the dosage and duration of immunosuppressive therapy. Complementary small animal studies demonstrated that immunosuppressive treatment dosage-dependently and reversibly impaired antibody production, primarily by depleting immune cells, notably B cells. A single shot of adenoviral vector-based vaccines demonstrated enhanced immunogenicity relative to two shots of alum-adjuvanted protein vaccines, inducing potent neutralizing antibodies (NAbs) and a Th1-biased T-cell response even under continuous immunosuppression. The enhanced response was driven by reduced interference from pre-existing antibodies, sustained transgene expression, and the reprogramming of lipid metabolism to activate T and B cells. Our findings advocate for tailored vaccination strategies, positioning adenoviral vectors as a candidate modality for this vulnerable population.

BackgroundKidney volumetry derived from CT has been proposed as a surrogate of renal function in living kidney donor evaluation. However, clinical integration has been limited by reader-dependent workflows and semiautomatic methods susceptible to image quality. PurposeTo evaluate whether fully automated CT-based segmentation of renal cortex, medulla and total parenchymal volume provides reproducible volumetric biomarkers associated with global and split renal function in living kidney donor candidates. Materials and MethodsIn this retrospective single-center study, 461 living kidney donor candidates (2003-2021) underwent contrast-enhanced abdominal CT. A convolutional neural network was trained to automatically segment cortical, medullary, and total parenchymal volumes on arterial-phase images. Segmentation performance was evaluated against manual reference annotations. Volumes were indexed to body surface area. Associations with eGFR, 24-hour creatinine clearance, cystatin C, and tubular clearance were assessed using Spearman correlation coefficient ({rho}), and side-specific volume fractions were compared with scintigraphy -derived split function. ResultsAutomated segmentation achieved excellent agreement with expert reference segmentations (Dice 0.95 for cortex; 0.90 for medulla). eGFR correlated moderately with cortical ({rho} = 0.46) and total parenchymal volume ({rho} = 0.45), and modestly with medullary volume ({rho} = 0.30). Similar associations were observed for other global measures, with the strongest correlation for cortical volume and tubular clearance ({rho} = 0.53). Side-specific volume fractions correlated with scintigraphy-derived split renal function ({rho} = 0.49-0.56; all p < 0.001). ConclusionAutomated CT-based renal subcompartment segmentation provides reproducible volumetric biomarkers within routine donor evaluation. Cortical volume performs comparably to total parenchymal volume and tracks split renal function at the cohort level, suggesting potential utility in donor assessment.

BackgroundThere is a need for synthetic peptide-based serologic assays that exploit avidity to replace whole antigens while enabling low-cost diagnostics in resource-limited settings. ObjectiveTo evaluate the diagnostic accuracy of a polymeric peptide-based ELISA leveraging avidity to enhance signal. MethodA 15-member SARS-CoV-2 peptide library corresponding to multiple epitope clusters and proteins was screened by indirect ELISA using pooled sera from RT-PCR-confirmed COVID-19 patients to identify peptides with possible diagnostic utility. The identified lead candidate, S559, possessed terminal cysteine-substitution to allow disulfide polymerization, and the resulting avidity gain was evaluated by comparing the apparent dissociation constant (KDapp) before and after depolymerization with N-acetylcysteine. The performance of an optimized ELISA using S559 was evaluated on 1,222 prospectively collected COVID-19 serum samples and 218 biobanked pre-COVID control serum samples. ResultsPolymeric S559 with a KDapp of 29.26 nM-1was demonstrated to have a 218% avidity gain relative to the completely depolymerized form. At pre-defined thresholds, the optimized S559 ELISA has a sensitivity and specificity of 83.39% (95%CI: 81.18% and 85.43%) and 96.79% (95%CI: 93.50% and 98.70%), respectively. At post hoc thresholds determined by Youden index, sensitivity and specificity reached 95.01 (95% CI: 93.63% - 96.16%) and 100.00% (95% CI: 98.32% - 100.00%), respectively. ConclusionHomomultivalent epitope presentation using polymeric S559 allows a highly specific immunoassay using human sera that may have important value in detecting antibodies, whether for diagnosing infection, confirming vaccination status or conducting surveillance.

Amatoxin-induced acute liver failure complicates misidentified foraged mushroom ingestion worldwide; abrupt multisystem collapse punctuates apparent improvement. Our prospective single-arm clinical trial investigated proactive toxicokinetic-based management to preserve elimination capacity: sustained enhanced hydration to maintain renal clearance; fasting plus octreotide to suppress meal-driven enterohepatic circulation; and intravenous silibinin to inhibit OATP1B3-mediated hepatic uptake, enabling safe passage and elimination of gallbladder-confined amatoxin-laden bile. Safety population (N=99) transplant-free recovery (TFR): 88.0% (87 recoveries, 6 transplants, 6 deaths). Protocol-adherent Efficacy population (n=86) TFR: 98.8% (85 recoveries, 1 transplant, 0 deaths). Multivariable analysis identified uninterrupted hydration as strongest TFR predictor (P<0.001), followed by earlier silibinin initiation (P=0.003); octreotide shortened INR recovery by 11 hours (P=0.033). These findings support a toxin elimination model in which preserved renal clearance and biliary sequestration are central recovery determinants. The kinetic balance between renal clearance and hepatic uptake governs both recovery and collapse.

BackgroundPreoperative biliary stenting alters biliary colonization and may reduce the effectiveness of perioperative antibiotic prophylaxis in pancreatoduodenectomy. Although broader-spectrum regimens have been associated with improved infectious outcomes, their microbiological adequacy in routine clinical practice remains poorly defined. We therefore evaluated the real-world adequacy of a prolonged ampicillin-sulbactam protocol, its association with infectious outcomes and survival, and the potential impact of a universal piperacillin-tazobactam strategy. MethodsWe analyzed all consecutive patients who underwent elective pancreatoduodenectomy from 2002 to 2023 at our tertiary center. Demographic, operative, microbiological, and outcome data were retrieved from a prospectively maintained database. Patients were stratified by stent status. Adequacy of prophylaxis was defined as the full in vitro susceptibility of all bile isolates. The outcomes included 30-day infectious morbidity, clinically relevant POPF, PPH, DGE, reoperation, 30- and 90-day mortality and long-term survival. A coverage simulation was performed to compare ampicillin-sulbactam with a hypothetical universal piperacillin-tazobactam. Statistical methods included chi-square/Fishers exact tests, Mann-Whitney U tests, Cox models, McNemars test and Poisson regression. ResultsOf 956 patients, 424 (44%) had a biliary stent. Technical complications were comparable between groups, and rates of POPF and PPH were not increased. However, infectious morbidity was higher in stented patients, including sepsis (RR 1.62, 95% CI 1.05-2.51) and postoperative cholangitis (RR 2.20, 95% CI 1.36-3.56). Thirty- and 90-day mortality were increased (RR 2.88 and 2.73) but lost significance after adjustment. Bile cultures predominantly yielded Enterococcus and Enterobacterales with low ampicillin-sulbactam susceptibility. Overall adequacy was 21.7%. Among patients with bile cultures (n = 474), ampicillin-sulbactam covered 43.7% (207/474) versus 81.2% (385/474) with piperacillin-tazobactam; in stented patients with cultures (n = 397), coverage increased from 41.8% to 78.1%. Adequate ampicillin-sulbactam coverage was not associated with reduced infectious outcomes in Poisson models. ConclusionPreoperative stenting creates a polymicrobial, partially resistant biliary niche that ampicillin-sulbactam does not sufficiently cover. Our data shows that a piperacillin-tazobactam strategy substantially improves coverage and was therefore implemented at our center. Core message- Stented patients exhibit a distinct infectious risk profile characterized by Enterococcus-and Enterobacterales-dominated bile colonization rather than increased rates of technical complications. - In stented patients, real-world microbiological coverage of ampicillin-sulbactam was limited, and in vitro susceptibility did not independently translate into reduced postoperative infectious morbidity. - Broader prophylaxis, such as piperacillin/tazobactam, aligns with the actual flora and nearly doubles theoretical coverage, addressing the mismatch between stent-associated biofilms and narrow regimens.

BackgroundReliable identification of early predictors of adverse outcomes was essential during the pre-vaccination phase of the COVID-19 pandemic. Few studies have comprehensively integrated clinical presentation, laboratory parameters including arterial blood gas analysis, and chest computed tomography (CT) findings within a single well-characterized cohort, particularly in underrepresented regions of Brazil. MethodsThis retrospective cohort study included 482 consecutive adults (median age 61 years [IQR 49-73]; 64.3% men) with RT-PCR-confirmed SARS-CoV-2 infection hospitalized at a tertiary cardiac center in Central-West Brazil between March 2020 and January 2021. Demographic, clinical, laboratory (including arterial blood gas analysis), and chest CT data obtained within 48 hours of admission were analyzed. Univariable logistic regression was performed for 76 variables. Multivariable models were constructed using an a priori variable selection strategy based on clinical relevance, representation of distinct pathophysiological domains, and adherence to events-per-variable principles. Complete-case analyses were performed without imputation. ResultsIn-hospital mortality was 9.3% (45/482). Invasive mechanical ventilation was required in 74 patients (15.4%), with a mortality rate of 58.1% among those ventilated. In univariable analysis, 42 variables were associated with mortality (p < 0.05). In multivariable analysis (n = 438), five independent predictors of death were identified: age (adjusted OR 1.66 per 10 years; 95% CI 1.19-2.32; p = 0.003), arterial pH (adjusted OR 0.47 per 0.1-unit increase; 95% CI 0.25-0.89; p = 0.021), neutrophil-to-lymphocyte ratio (adjusted OR 1.30; 95% CI 1.18-1.44; p < 0.001), number of comorbidities (adjusted OR 1.59; 95% CI 1.25-2.02; p < 0.001), and serum creatinine (adjusted OR 1.37; 95% CI 1.05-1.77; p = 0.019). The model demonstrated good calibration (Hosmer-Lemeshow p > 0.05) and moderate-to-high explanatory power (Nagelkerke R{superscript 2} = 0.43). For the composite outcome of death or invasive mechanical ventilation (74 events; 15.4%), four predictors remained independently associated; serum creatinine showed a non-significant trend (p = 0.069). On chest CT (n = 424), analyzed descriptively and in univariable models only, pulmonary involvement > 50% was associated with increased odds of death (OR 2.87; 95% CI 1.42-5.79; p = 0.003). ConclusionsFive admission variables representing distinct pathophysiological domains--age, arterial pH, neutrophil-to-lymphocyte ratio, comorbidity burden, and serum creatinine--were independently associated with in-hospital mortality in this pre-vaccination cohort. Arterial pH provided independent prognostic information beyond inflammatory and renal markers. These findings support early risk stratification using routinely available clinical data.

The host response to Neisseria gonorrhoeae is variable, and understanding its systemic and local components is critical to understanding anti-gonococcal immunity for vaccine development. We used a controlled human infection model of male gonococcal urethritis in naive volunteers in combination with multiplex cytokine analyte analysis of blood and urine specimens taken before infection, at the time of acute symptoms, and after curative treatment of N. gonorrhoeae to study responses to early infection. (This study utilized data and specimens from all 11 participants assigned to control arms of two previous randomized clinical trials). All 11 participants developed urethritis between 2 and 5 days post inoculation with N. gonorrhoeae strain FA1090, with a majority having visible discharge by day 3. In urine, we found increases in IL-1RA, G-CSF, and chemokines CXCL10, CCL4, CCL11, GRO/{beta}/{gamma}, and IL-8/CXCL8, with IL-1RA and CCL4 showing direct correlation with the degree of pyuria at the time of infection. Contrary to a prior study using the human challenge model and N. gonorrhoeae strain MS11mkC, we did not see similar increases in urine IL-6, TNF-, or IL-1{beta}, although differences in IL-6, TNF- were observed in participants with later development of infection. Additionally, plasma cytokine levels were unchanged in this cohort over the course of their infection, suggesting these infections were confined to the urethra. We propose that differences in strain virulence or the threshold to define a clinical case may be responsible for this discrepancy, meriting further study and continued use of non-invasive inflammatory markers to study local effects in addition to systemic effects of gonococcal infection. Author SummaryGonorrhea, caused by the bacterium Neisseria gonorrhoeae, remains a global public health concern, yet repeated infections are common and no vaccine is available. A key challenge for vaccine development is limited understanding of how the human immune system responds during early infection, when bacteria are confined to the urethra, vagina, or other mucosal sites. To address this gap, we studied immune responses in a controlled human infection model in which male volunteers with no prior exposure were experimentally infected with N. gonorrhoeae into their urethra. Immune signaling molecules were measured in urine and blood samples collected before infection, during symptoms, and after antibiotic treatment. All participants developed urethral inflammation within a few days of infection. We observed marked increases in multiple inflammatory cytokines in urine, some which correlated with the degree of neutrophils in their urine. In contrast, immune markers in the bloodstream remained largely unchanged. These findings suggest that early infection with the N. gonorrhoeae strain tested triggers a strong localized immune response without widespread systemic inflammation. Our results highlight the value of urine-based, non-invasive sampling and demonstrate the power of human challenge models for studying early immune responses that have been difficult to characterize in animal systems.

BackgroundHospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP), particularly those caused by multi-drug resistant organisms (MDROs), often require newer antibiotic treatment. The efficacy and safety of newer antibiotics compared to generic antibiotics in randomized controlled trials (RCTs) have not been evaluated before. MethodsIn this systematic review, we searched RCTs in the United States National Library of Medicine (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, Ovid MEDLINE, Clinical Trials.gov and Google Scholar databases published between 2013 and 2025. The primary efficacy endpoint was 28-day all-cause mortality. Secondary efficacy endpoints were clinical and microbiological response. Safety endpoint was nephrotoxicity. ResultsWe identified eight eligible RCTs involving 2,881 patients (1,450 patients treated with newer antibiotics and 1,431 patients treated with generic antibiotics) with HABP/VABP. The meta-analysis did not reveal any significant differences between newer and generic antibiotics for all-cause mortality at day 28 (risk ratio (RR) 0.97, 95% confidence interval (CI) 0.72-1.30), clinical response (RR 1.04, 95%CI 0.93-1.17), and microbiological response (RR 1.05, 95%CI 0.89-1.24). However, newer antibiotics showed significant lower occurrences of nephrotoxicity compared to colistin component (RR 0.30, 95%CI 0.11-0.79). In subgroup analysis, newer antibiotic regimens demonstrated significant improvement in microbiological eradication of carbapenem-resistant Gram-negative bacilli (RR 1.50, 95%CI 1.18-1.90). ConclusionsNewer antibiotics showed similar efficacy and safety in treating HABP/VABP compared to generic drugs. The superiority in microbiological eradication of carbapenem-resistant Gram-negative bacilli of newer antibiotics could suggest that future trials should be targeted for those patients to improve understanding of their therapeutic use and pathophysiology of these conditions. Key pointsNewer antibiotics, despite broader antimicrobial coverage, have not significantly outperformed generic comparators in terms of 28-day all-cause mortality, clinical, or microbiological response in patients with Gram-negative HABP/VABP. This may reflect limitations in current trial designs focused primarily on regulatory approval.

Syphilis remains a major public health concern. However, current serologic assays are limited in their ability to distinguish active from previously treated disease. We applied tandem mass tag-based quantitative proteomics to plasma from 10 adults with active syphilis and 10 age- and gender-matched non-diseased controls. We identified 54 differentially regulated proteins (36 upregulated, 18 downregulated). Those proteins map to immune and inflammatory responses, acute-phase signaling, coagulation and vascular pathways, and cellular stress processes. Three sets of between 2-5 proteins achieved >99% discrimination between cases and controls. Our exploratory findings support proteomics as a potential tool to develop novel syphilis diagnostics.

BackgroundInterleukin-6 (IL-6) is a cytokine that plays a key role in systemic hyperinflammation and may mediate the relationship between acute COVID-19 and severe long-term outcomes such as Long COVID or death. IL-6 modulating drugs may reduce patients risk of severe post-COVID-19 outcomes. MethodsWe conducted an emulated target trial in a retrospective cohort of patients with moderate-to-severe rheumatoid arthritis who were prescribed IL-6 receptor antagonists (sarilumab or tocilizumab, pooled treatment) or other biologic agents (anakinra or baricitinib, pooled comparator) in 2022. We compared the 12-month cumulative incidence of mortality and Long COVID (diagnosed and probable) between groups using Super Learner and targeted maximum likelihood estimation, adjusting for covariates of interest. ResultsIn our cohort of 3,553 patients, we found that prescription of IL-6 receptor antagonists was associated with a lower 12-month cumulative mortality (adjusted relative risk (aRR) 0.40, 95% CI 0.27, 0.59), diagnosed Long COVID aRR 0.42, 95% CI 0.23, 0.78), and probable Long COVID (aRR 0.71, 95% CI 0.61, 0.83), compared to prescription of other biologic agents, among rheumatoid arthritis patients. ConclusionsIL-6 receptor antagonists may prevent the incidence of severe post-COVID-19 outcomes, such as Long COVID or mortality. This supports the hypothesis that IL-6 may be a mechanistic biomarker of COVID-19 sequelae and that acute COVID-19 severity may mediate this relationship.

BackgroundThe role of the gut microbiome and specific enteric bacteria in influencing the development of colorectal cancer (CRC) remains incompletely understood. Recently, it was shown that human CRC-derived strains of Clostridioides difficile were capable of inducing colonic tumorigenesis in a susceptible mouse model. We hypothesized that C. difficile contributes to the pathogenesis of human CRC and would be enriched in CRC tumors compared to paired normal tissues from the same individual. MethodsWe analyzed matched tumor/normal tissue samples from a cohort of 108 individuals presenting to a tertiary care hospital in Kuala Lumpur, Malaysia for CRC resection between 2013-2014. We assessed the prevalence of C. difficile detection using 16S rRNA amplicon sequencing with high-resolution taxonomic assignment as well as culture and PCR. ResultsWe found that detection of C. difficile was prevalent (38% of individuals), but of low abundance (tumor median relative abundance 0.01%, paired normal 0.006% [p=0.4]). Detection of C. difficile was more prevalent in individuals with biofilm-positive tumor tissues than biofilm-negative (i.e., 81% of C. difficile-positive individuals were biofilm-positive vs. 63% of C. difficile-negative individuals [p=0.04]). Additionally, in exploratory analyses, we describe patterns of taxonomic and inferred functional pathway differences between C. difficile-positive and C. difficile-negative groups. ConclusionThese findings suggest that C. difficile is frequently present in low abundance in the tumor microbiome with a potentially significant impact on community composition and function.

BackgroundDengue virus (DENV) appears to manipulate several cellular metabolic pathways to permit its replication and immune evasion in the host. Here, we employed high-resolution mass spectrometry (HR-MS) to investigate the serum metabolomic landscape of clinical DENV infection. MethodsSerum specimens from primary dengue (n=11), secondary dengue (n=9) samples, and healthy controls (n=10) were used for untargeted and targeted metabolomic quantification on a Waters Xevo G2-XS QTof Mass Spectrometer. The binding potential of selected ligands against DENV NS1, NS3, and NS5 was evaluated. Crystal structures were retrieved from Protein Data Bank and prepared using the Schrodingers protein preparation wizard. Based on findings from untargeted metabolomics, we validated certain bioactive lipid metabolites using commercial enzyme immunoassays. ResultsSerum metabolomic profiling revealed multiple distinct patterns for primary and secondary dengue versus controls. A consistent peak was observed at 2.06 mins across all samples. Certain bioactive lipid metabolites, such as, lysophospholipids, phosphatidylcholines, phosphatidylserines, and phosphatidylinositols, were detected alongside carnitine fragments, ceramides, diacylglycerols (DAGs), and bile acid conjugates in dengue. Molecular docking showed that DAG consistently exhibited strong binding to all the DENV proteins. Notably, LPC 22:6 showed a selectively strong affinity for NS5. Enzyme validation showed that in the secondary dengue cohort, LPC was significantly elevated than primary and healthy controls (p<0.05). ConclusionsOur investigations of the metabolomic landscaping, unveiled certain characteristic anabolic shift revealing metabolic vulnerabilities in clinical DENV infection, warranting investigations for use as potential biomarkers of inflammation in disease diagnosis and prognosis. Author summaryDengue is a mosquito-borne tropical viral infection that can range in severity from asymptomatic to life-threatening manifestations. Dengue virus (DENV) hijacks cellular machinery to sustain its survival in the host. Using high-resolution mass spectrometry (HR-MS), we studied the serum metabolomic imprints of dengue infection. The binding ability of selected metabolomic ligands against DENV NS1, NS3, and NS5 was studied. We found several distinct retention patterns for the dengue cases, with a consistent peak at 2.06 min across all samples. Further, several bioactive lipid metabolites were detected in the dengue infected cohort. Our molecular docking studies showed that diacylglycerol, a lipid metabolite exhibited strong binding with all the DENV proteins. We concluded that certain unique lipid metabolomic imprints exist in clinical DENV infection. The identified metabolomic signatures reveal significant potential for metabolomics to elucidate host-virus interactions, contributing to the advancement of antiviral and symptomatic treatments, along with prognostic or diagnostic biomarkers of dengue disease.

BackgroundNo randomized clinical trial comparing the most established new modalities of treatment for patients with localized prostate cancer has been published, and there is scarce comparative effectiveness research assessing Patient-Reported Outcome Measures (PROMs). Objectiveto compare the impact of active surveillance, robot-assisted radical prostatectomy (RARP), Intensity-modulated radiotherapy (IMRT), and real-time brachytherapy on patients, through PROMs, from pre-treatment to five years after diagnosis of localized prostate cancer. MethodsProspective observational study (ClinicalTrials.gov, NCT05523856) of 566 male patients diagnosed in 2014 to 2021 with clinically localized prostate cancer (50-75 years old; stage cT1 or cT2, N0/Nx and M0/Mx; Gleason [&le;] 6 or 7 (if 3 + 4 with T1c); and PSA [&le;] 10 ng/ml) and followed until 2019-2026. The Expanded Prostate Cancer Index Composite (EPIC-26) measures urinary incontinence, urinary irritative/obstructive symptoms, sexual, bowel and hormonal domains. EPIC-26 was centrally administered via telephone interviews before treatment and then annually after treatment. Generalized estimating equation (GEE) models were constructed with overlap propensity score-based weights and adjusted by age and clinical tumor stage. ResultsWeighted results of adjusted GEE models showed significant declines for sexual health during the 5yr in all treatment groups (ranging from -19.8 to -27.6), but this worsening appeared earlier in those of active treatment (RARP, IMRT and brachytherapy) than in active surveillance. The RARP group presented the greatest deterioration in urinary incontinence (-28.5 vs -11.7 in active surveillance), while the greatest impairment in bowel symptoms was observed in both radiotherapy groups (around -3 vs +0.3 in active surveillance). ConclusionOur findings provide detailed novel evidence, measured over 5 yr, on the long-term impact of disease and treatment on patients with localized prostate cancer. While all treatment groups showed large sexual deterioration overtime, important differences in urinary incontinence (highest after RARP) and bowel symptoms (after IMRT and brachytherapy) persisted. These findings can inform patients during shared decision-making on the alignment between localized prostate cancer treatment choices and their priorities.

BackgroundRetrieval-augmented generation (RAG) frameworks such as RAPID [1] have demonstrated that staged planning and retrieval grounding improve long-form text generation. However, most implementations remain similarity-driven and open-domain, lacking the epistemic safeguards required for biomedical synthesis, where mechanistic completeness, temporal governance, traceability, and explicit gap classification are essential. ObjectiveTo develop and evaluate a topology-aware, graph-augmented retrieval framework for structured biomedical narrative synthesis, and to position it as a domain-constrained evolution of staged RAG aligned with structural principles of digital evidence-based medicine (dEBM). MethodsWe implemented a two-layer architecture operating on a closed, version-controlled corpus of 11,861 peer-reviewed text chunks on iron deficiency. A metadata-constrained vector retriever (RAG01) was extended with a Graph-RAG (RAG02) overlay (RAG02) constructed from chunk-level entity extraction and weighted co-occurrence networks (30 nodes; 118 directed edges). Topic planning was organized through predefined mechanistic axes functioning as structured hypothesis probes. Retrieval was performed under identical deterministic constraints (top-k = 5; cosine threshold = 0.50; publication year [&ge;] 2023), and graph diagnostics--including local connectivity, induced subgraph density, modular overlap, and multi-hop stability--were used to distinguish retrieval insufficiency from corpus-level evidentiary scarcity. ResultsIn a case study of obesity-associated iron deficiency, the entity network exhibited a centralized regulatory topology with hepcidin as a high-connectivity hub. Axis-based retrieval combined with graph auditing consistently reinforced an inflammation-mediated hepcidin pathway linking obesity to iron deficiency, while alternative mechanisms lacked stable multi-hop embedding. Compared with vector-only retrieval, graph augmentation preserved semantic alignment and increased mean cosine similarity from 0.673 to 0.694 while reducing similarity dispersion (SD 0.056 to 0.035) under identical constraints. Graph activity ratio was 1.00 in the temporally filtered corpus. ConclusionsBy integrating mechanistic axis decomposition, topology-aware auditing, causal scaffolding, and expert-driven iterative refinement, the proposed framework implements selected structural constraints inspired by evidence-based medicine within a controlled digital synthesis environment. The approach advances retrieval-augmented generation beyond similarity-based summarization toward a reproducible model of topology-aware biomedical evidence interrogation with implications for AI-assisted systematic reviews.

BackgroundA Hospital Medicine Advanced Practice Provider (HMAPP)-led care model developed in response to the high acuity and increased patient volumes associated with the Covid-19 pandemic. Although anecdotally perceived as a successful model, questions remained if there was adequate pre-planning and formal implementation strategy for stakeholder buy-in. ObjectiveTo elicit HM physicians and APPs perceptions of the HMAPP-led care model implementation and consider necessary steps for optimal future APP care model development and operation. Design, Setting and ParticipantsThis qualitative study used 10 (5 physicians and 5 APPs involved in the care model pre- and post-implementation) individual semi-structured, virtual interviews based on the Consolidated Framework for Implementation Research (CFIR). Deductive and inductive rapid analysis was utilized to analyze the data. ResultsTwo themes emerged as strengths: 1) Experienced APPs delivered the care model, 2) Acceptance of the care model evolved over time. Four themes suggested opportunities for future development: 1) Guidelines should expand from patient distribution to include minimal collaboration and escalation expectations, 2) Culture change was a barrier to model implementation and acceptance, 3) Intentional collaboration between APPs and Physicians is necessary, 4) Investment in standardized onboarding enhances buy-in of the care model. ConclusionThe impact of an APP care model can be elevated if implemented with key principles and strategies. This is critical in an evolving health care landscape where all providers need to collaborate and practice with their full expertise to maximize safe, efficient and quality patient care.

BackgroundHypertension is a growing contributor to morbidity and mortality in sub-Saharan Africa, yet many adults are still unaware of how to prevent it. In Zambia, preventive behaviours such as regular exercise, reduced salt intake, and routine blood pressure checks are underutilised. This study examined the factors associated with hypertension prevention practices among adults in Mtendere Compound, a high-density residential area in the capital-city of Zambia Lusaka. MethodsA cross-sectional study was conducted among 382 adults aged 18 to 65 years, selected through multistage random sampling. Data were collected using structured interviewer-administered questionnaires adapted from the WHO-STEPS tools. Key variables included demographic characteristics, knowledge of hypertension, health-seeking behaviour, and lifestyle factors. Descriptive statistics and logistic regression were used to analyse associations between independent variables and hypertension prevention practices as a compound outcome variable including low salt intake, regular exercises and check-ups. ResultsAmong participants, 58.6% showed adequate knowledge of hypertension prevention. However, only 41.1% reported practising at least three recommended behaviours. Receiving health advice at a facility (AOR: 3.09, 95% CI: 1.72-5.56), having good knowledge (AOR: 2.64, 95% CI: 1.46-4.75), and being employed (AOR: 1.78, 95% CI: 1.02-3.09) were independently associated with practicing preventive behaviours. Age, sex, and education level were not statistically significant predictors. ConclusionWhile majority of the respondents had adequate knowledge of hypertension prevention, the actual practice was low. This study underscores the community-based reinforcement of social behavioural change (SBC) to transform knowledge into practice among at risk populations. Specifically, the study recommends tailoring interventions on hypertension prevention to reach unemployed and under-informed populations informal settlements and other high-density settings in major towns and cities in sub-Saharan Africa.