Hospital for Tropical Diseases

While participatory research is increasingly used in global health, more has been written for researchers compared to communities. This article synthesizes insights from a community panel convened during a participatory research workshop. The discussion identified key factors for communities to understand and assumptions to set aside when beginning participatory research. These considerations may help communities navigate power imbalances, inclusively design, and participate as more equal partners in research. Implications for participatory methodology and partnership training are also discussed.

BackgroundCardiovascular disease screening faces significant challenges in resource-limited settings, where infrastructure and computational constraints preclude advanced assessment. These constraints are particularly acute for people living with human immunodeficiency virus (HIV), who experience elevated cardiovascular risk yet often receive care in clinics without specialist diagnostic capacity. Pretrained physiological foundation models offer potential for low-cost screening using wearable sensors, though their applicability in resource-constrained settings remains unclear.MethodsWe evaluate pretrained physiological embeddings from foundation models for cardiovascular disease detection using photoplethysmography signals from 80 people living with HIV in Ho Chi Minh City, Vietnam. Of 80 participants, 13 (16%) had cardiologist-confirmed cardiovascular disease. We compare strictly zero-shot deployment (NormWear without local training) with frozen PaPaGei embeddings plus locally trained classifier, alongside traditional approaches.ResultsHere we show that the PaPaGei-embedding approach achieves area under the receiver operating characteristic curve 0.769 (95% confidence interval: 0.70, 0.84) and average precision 0.489 (0.37, 0.61) in this pilot cohort, numerically higher than zero-shot NormWear (0.610; 0.226), principal component analysis features (0.651; 0.208), and supervised clinical models (0.744; 0.433). This approach requires local labels for classifier training but avoids computationally intensive foundation model fine-tuning. However, given the small positive class size (13 cases), these findings require validation in larger cohorts. PaPaGei embeddings capture clinically coherent structure: patients on dolutegravir-based regimens cluster in low-risk regions, while those with high cholesterol variability occupy high-risk areas.ConclusionsThese preliminary findings provide a potential methodological framework for deploying foundation models in resource-constrained settings, though adequately powered, multi-centre validation is essential before clinical implementation.

Hepatitis B virus (HBV) can persist in peripheral blood mononuclear cells (PBMCs) as an extrahepatic reservoir in treatment-naive patients; however, its persistence during long-term nucleos(t)ide analogue therapy with sustained serum viral suppression remains unclear. This study aimed to evaluate the frequency and predictors of HBV DNA detectability in PBMCs of chronic hepatitis B (CHB) patients following long-term nucleos(t)ide analogue therapy-induced sustained serum viral suppression. Eighty-eight CHB patients, on long-term tenofovir disoproxil fumarate ( n = 44) or entecavir ( n = 44) with greater than 2 years of sustained viral suppression, were enrolled. PBMCs were tested for HBV DNA by quantitative PCR. Clinical and laboratory data were analyzed to identify predictors of PBMC HBV DNA detection. Receiver operating characteristic analysis assessed the performance of posttreatment serum quantitative hepatitis B surface antigen (qHBsAg). HBV DNA was detected in PBMCs of eight (9.1%) patients, equally distributed between treatment groups. Pretreatment hepatitis B e-antigen (HBeAg) positivity predicted PBMC HBV DNA detection ( P = 0.036). PBMC HBV DNA-positive patients were older males with worse baseline liver chemistry and advanced fibrosis. Posttreatment qHBsAg was higher in PBMC HBV DNA-positive patients (139.5 vs. 21.5 IU/ml; P < 0.001) and strongly correlated with PBMC viral load ( r = 0.905, P = 0.002); qHBsAg greater than 89 IU/ml predicted PBMC HBV DNA detection with high accuracy. HBV DNA may persist in PBMCs despite long-term nucleos(t)ide analogue therapy-induced sustained viral suppression. Pretreatment HBeAg positivity and elevated posttreatment qHBsAg can help identify patients at risk, highlighting the need to monitor extrahepatic reservoirs in CHB management.

ABSTRACT The limited availability of low-salinity water in the northeastern semi-arid region of Brazil is one of the main constraints to the expansion of irrigated agriculture. In this context, the objective of this study was to evaluate the effects of irrigation with saline water on the salinity tolerance of guava during the rootstock formation phase. The experimental design was a randomized complete block in a 2 x 5 factorial scheme, consisting of two guava genotypes (Crioula and cv. Paluma) and five levels of irrigation water electrical conductivity (ECw: 0.3, 1.2, 2.1, 3.0, and 3.9 dS m-1), with six replicates. Stem diameter, plant height, fresh biomass of leaves, stems, and roots, and the accumulation of dry biomass in leaves, stems, roots, and total biomass were measured, along with Dickson quality index, transpiration rate, stomatal conductance, CO2 assimilation rate, and the absolute and relative growth rates in plant height. Irrigation using water with electrical conductivity above 0.3 dS m-1 inhibited stem diameter growth, root dry biomass, leaf transpiration, relative growth rate in height, and Dickson quality index in guava seedlings. Among the genotypes, Crioula showed greater growth, photosynthetic activity, and Dickson quality index under saline water irrigation, indicating its potential for use as a rootstock under semi-arid conditions.

Parasitic diseases have always caused a significant burden in endemic countries. However, due to globalization and immigration, more cases are emerging in non-endemic regions, leading to a growing incidence in solid organ transplantation. These immunocompromised patients, such diseases, have the potential to reactivate and cause severe disease and graft damage, often leading to death. Two specific parasites play a special role in the heart transplant scenario: Trypanosoma cruzi, responsible for Chagas disease, and Toxoplasma gondii, for Toxoplasmosis. In endemic countries, Chagas disease is not only one of the main indications for a heart transplant, but also responsible for several episodes of reactivation after transplantation, requiring careful surveillance for preemptive treatment. T. gondii has the potential to reactivate in immunocompromised hosts, leading to myocarditis and/or disseminated disease, often fatal. Prophylaxis is safe and effective to prevent reactivation. This review aims to summarize the most important aspects of Chagas disease and Toxoplasmosis in the heart transplant setting, with emphasis on pre-transplant screening, prophylaxis, and monitoring.

Introduction: Human Immunodeficiency Virus (HIV) infection remains a major public health problem, particularly in sub-Saharan Africa. Despite expanded access to antiretroviral therapy (ART), many patients are still admitted at an advanced stage of the disease, characterized by severe immunosuppression and high morbidity. In this context, the evaluation of biological parameters is an essential tool for the monitoring and management of patients with advanced HIV disease (AHD). Methodology: A retrospective and analytical study was conducted at the Care, Training, and Research Unit (CTRU) of Donka National Hospital over a four-year period (2016-2020). All patients aged 15 years or older hospitalized for advanced HIV infection (CD4 &lt; 200 cells/mm³ or clinical stage III/IV according to the WHO) were included. Sociodemographic, clinical, and biological data were collected and analyzed using Epi Info 7.2.2.6 software, with a significance threshold set at p &lt; 0.05. Proportions were compared using the chi-square (χ²) test, while means were compared using analysis of variance (ANOVA). Results: A total of 2,236 HIV-infected patients were hospitalized during the study period. Of these, 1,861 (83.22%) were over 15 years of age, in accordance with the inclusion criteria, and were included in the analysis. The study population was predominantly female, with 1,144 women (61.47%) compared to 717 men (38.53%), representing a male-to-female ratio of 0.6. The most represented age group was 35 to 44 years old (590 patients, or 31.70%). The average age of participants was 38.69 ± 12.07 years, ranging from 15 to 79 years. HIV-1 accounted for 99.2% of cases. Nearly half of patients (48.1%) had a CD4 count &lt; 50 cells/mm³ and 89.6% had a detectable viral load. Severe anemia (&lt; 8 g/dL) was observed in 47.6% of patients, leukopenia in 45.1%, and neutropenia in 50%. Renal failure (creatinine &gt; 150 µmol/L) was observed in 44.4% of cases. Mortality was significantly associated with WHO stage IV (p = 0.00002) and a CD4 count &lt; 50 cells/mm³ (p = 0.00003). Conclusion: This study highlights the high frequency of biological abnormalities in patients admitted to the USFR Donka in the advanced stages of HIV infection, characterized by profound immunodeficiency, severe cytopenias, and largely uncontrolled viral load. The major prognostic factors for mortality identified clinical stage IV and CD4 count &lt; 50 cells/mm³ confirm the severity of these advanced forms.

Background and aim: A significant percentage of Egyptians have H pylori infection, but its association with insulin resistance (IR) remains unclear. Our goal was to determine how non-insulin-based IR markers — especially the metabolic score for IR (METS-IR), the triglyceride glucose index (TyG), and the triglyceride-to-High-Density Lipoprotein Cholesterol Ratio (TG/HDL-C) — are distributed in an Egyptian population. Additionally, the study explored the link between metabolic syndrome (MS) and H. pylori.Patients and Methods: A cross-sectional study included 200 participants from Tanta University Hospitals. Group I included 100 patients who tested positive for H. pylori in stool samples, while Group II included 100 participants who tested negative. The study investigated the link between these indicators and H. pylori.Results: MS was found in 32% of participants, with 62.5% being H pylori-positive. H pylori-positive patients showed higher TG/HDL-C ratio and TyG index, but there was no significant difference in METS-IR. The univariate analysis revealed a link between H. pylori and MS, but the multivariate analysis identified age, hypertension, and waist circumference as the main risk factors.Conclusions: These findings show a clear link between H. pylori and the TG/HDL-C ratio and TyG index, which may help identify Egyptians at risk for IR. We also found that age, hypertension, and waist circumference were strong predictors of metabolic syndrome.

ObjectivesTo evaluate the accuracy of the arterial oxygen partial pressure/inspired oxygen fraction (PaO2/FiO2) ratio in predicting mortality among acute respiratory distress syndrome (ARDS) patients in Vietnam.DesignA retrospective observational study.SettingA central hospital in Vietnam.ParticipantsAdult patients diagnosed with ARDS based on the Berlin definition and admitted to Bach Mai Hospital between August 2015 and August 2023. ARDS severity was converted from descriptive categories to the Berlin score, ranging from 1 (PaO2/FiO2>300 mm Hg) to 4 (PaO2/FiO2≤100 mm Hg).Primary outcomeAll-cause hospital mortality.ResultsOf 345 patients, 67.5% were male, and the median age was 55.0 years (IQR: 39.0–66.0). Hospital mortality was 61.2% (211/345). On the first day of admission, the PaO2/FiO2 ratio (areas under the receiver operating characteristic curves (AUROC): 0.585 (95% CI 0.522 to 0.649)) showed limited predictive ability for hospital mortality. Incorporating the PaO2/FiO2 ratio into the Berlin score did not substantially improve accuracy (AUROC: 0.578 (95% CI 0.516 to 0.641)). Both measures were less accurate than Sequential Organ Failure Assessment (SOFA) (AUROC: 0.650 (95% CI 0.590 to 0.711)), Acute Physiology and Chronic Health Evaluation II (APACHE II) (AUROC: 0.685 (95% CI 0.628 to 0.742)) and Confusion, Urea >7 mmol/L (20 mg/dL), Respiratory rate ≥30 breaths/min, Blood pressure (systolic <90 mm Hg or diastolic ≤60 mm Hg) and Age ≥65 years (CURB-65) (AUROC: 0.689 (95% CI 0.617 to 0.762)). Higher PaO2/FiO2 values (adjusted OR, AOR: 0.988 (95% CI 0.979 to 0.996)) were independently associated with lower mortality risk, while higher Berlin (AOR: 2.477 (95% CI 1.190 to 5.156)), SOFA (AOR: 1.278 (95% CI 1.102 to 1.482)), APACHE II (AOR: 1.236 (95% CI 1.108 to 1.379)) and CURB-65 (AOR: 7.142 (95% CI 2.581 to 19.763)) scores were associated with increased mortality risk.ConclusionsIn this study of ARDS patients in Vietnam, the PaO2/FiO2 ratio demonstrated limited discriminatory ability for hospital mortality, and incorporating it into the Berlin score did not meaningfully improve performance. While less accurate than SOFA, APACHE II and CURB-65 scores, the PaO2/FiO2 ratio and Berlin score remained independently associated with mortality risk. These findings should be interpreted cautiously, given the retrospective design, single-centre setting and potential selection bias; further validation in larger, multicentre studies is warranted.