ABSTRACT
BACKGROUND: Epstein-Barr virus (EBV) infection is ubiquitous and in sub-Saharan Africa, occurs early in life. In a population-based rural African cohort, we leveraged historical samples from the General Population Cohort (GPC) in Uganda to examine the epidemiology of infection with EBV over time, in the era of HIV. METHODS: We used 9024 serum samples collected from the GPC in 1992, 2000, 2008, from 7576 participants across the age range (0-99 years of age) and tested for anti-EBV immunoglobulin G (IgG) antibodies to EAd, VCA, and EBNA-1 using a multiplex bead-based assay. The related gammaherpesvirus, Kaposi's sarcoma-associated herpesvirus (KSHV) seropositivity was also determined by detection of anti-KSHV IgG antibodies to K8.1 or ORF73 measured by recombinant protein enzyme-linked immunosorbent assay. Data on sex, age, and HIV serostatus were also collected. EBV seropositivity was modeled with age (excluding those under one year, who may have had maternal antibodies), sex, HIV serostatus, and KSHV serostatus using generalized linear mixed effects models to produce beta estimates. RESULTS: More than 93% of children were EBV seropositive by one year of age. EBV seropositivity was significantly associated with KSHV seropositivity. Anti-EBNA-1 antibody levels decreased with increasing age and were lower on average in people living with HIV. In general, anti-EAd antibody levels increased with age, were higher in males and KSHV seropositive persons, but decreased over calendar time. Anti-VCA antibody levels increased with age and with calendar time and were higher in KSHV seropositive persons but lower in males. CONCLUSIONS: This is the first study to identify factors associated with EBV antibodies across the entire life-course in rural sub-Saharan Africa. Consistent with other studies, EBV was near ubiquitous in the population by age one year. Patterns of antibodies show changes by age, sex and calendar time, but no association with HIV was evident, suggesting no relationship between EBV sero-epidemiology and the spread of HIV in the population over time in Uganda.
ABSTRACT
INTRODUCTION: Fibrin degradation product D-dimer can be a valuable indicator for venous thromboembolism (VTE). The use of D-dimer testing in primary care settings can be limited by restricted access to laboratory services. This performance evaluation compares a quantitative, point-of-care (POC) D-dimer assay (LumiraDx D-Dimer Test) with a reference laboratory-based D-dimer assay. METHODS: Plasma samples from patients presenting to secondary care in the UK, USA, and Germany were analyzed centrally using the LumiraDx D-Dimer Test and the reference test (bioMérieux VIDAS D-Dimer Exclusion II immunoassay). Method comparison used Passing-Bablok regression analysis with pre-specified equivalence criteria of r ≥ 0.9 and slope of 0.9-1.1. The NOVEL-3 study (NCT04375982) compared equivalency of fingerstick, venous blood (VB), and plasma samples from the same patient, tested at US primary care clinics next to the patient using the POC LumiraDx D-Dimer device. Measurements obtained from fingerstick and VB samples were compared with results from plasma samples, using Deming regression. The healthy reference range was determined using plasma samples of healthy volunteers, collected by commercial suppliers in Germany and the USA, which were analyzed centrally using the LumiraDx D-Dimer Test and the reference test. RESULTS: The LumiraDx D-Dimer Test demonstrated agreement with the bioMérieux VIDAS D-Dimer Exclusion II immunoassay for plasma samples (r = 0.923, slope of 1.016, n = 1767). There was good agreement between fingerstick/VB samples and plasma samples (r = 0.980-0.986, n = 93) measured using the LumiraDx D-Dimer Test. Overall error rates were 1.8%. The healthy reference range 90% percentile for D-dimer was calculated as 533 µg/l fibrinogen equivalent units (FEU). CONCLUSIONS: The quantitative LumiraDx D-Dimer Test is easy to use and can accurately measure D-dimer levels in a range of blood sample types, including fingerstick samples, which could improve assessment of VTE cases in community and hospital near-patient settings.
ABSTRACT
Baseline characteristics, disease-management and outcome of 1000 lower-risk myelodysplastic syndrome (MDS) patients within the European LeukaemiaNet MDS (EUMDS) Registry are described in conjunction with the validation of the revised International Prognostic Scoring System (IPSS-R). The EUMDS registry confirmed established prognostic factors, such as age, gender and World Health Organization 2001 classification. Low quality of life (EQ-5D visual analogue scale score) was significantly associated with reduced survival. A high co-morbidity index predicted poor outcome in univariate analyses. The IPSS-R identified a large group of 247 patients with Low (43%) and Very low (23%) risk score within the IPSS intermediate-1 patients. The IPSS-R also identified 32 High or Very high risk patients within the IPSS intermediate-1 patients. IPSS-R was superior to the IPSS for predicting both disease progression and survival. Seventy percent of patients received MDS-specific treatment or supportive care, including red blood cell transfusions (51%), haematopoietic growth factors (58%) and iron chelation therapy (8%), within 2 years of diagnosis; while 30% of the patients only required active monitoring. The IPSS-R proved its utility as a more refined risk stratification tool for the identification of patients with a very good or poor prognosis and in this lower-risk MDS population.
