Objective. To determine whether patients with rheumatoid arthritis (RA) have elevated Epstein-Barr virus (EBV) load in their peripheral blood mononuclear cells (PBMCs) and whether it is correlated with the HLA-DR genes they express, we developed an accurate EBV DNA quantitative assay using real-time polymerase chain reaction (PCR) with fluorescent probes.Methods. We studied the EBV DNA load in the PBMCs of 84 patients with RA, 69 normal controls, and 22 patients with rheumatic conditions other than RA. A 214-bp segment from the long internal repeat of EBV was amplified from 500 ng of PBMC DNA (150,000 cells) and quantified by real-time PCR with fluorescent probes.Results. We demonstrated that in patients with RA, the EBV DNA load in PBMCs is increased almost 10-fold compared with that in normal controls. The EBV load is stable over time and is not obviously influenced by disease-modifying antirheumatic drugs or HLA-DR.Conclusion. Patients with RA have elevated EBV load in their peripheral blood.

Objective. We previously demonstrated that patients with rheumatoid arthritis (RA) have a 10-fold systemic EpsteinBarr virus (EBV) overload, very similar to that observed in healthy organ transplant recipients. Our objective was to monitor EBV load over time in patients with RA receiving methotrexate, infliximab, or etanercept to detect possible immunosuppression-associated EBV dysregulation, as described in posttransplant lymphoproliferative disease. Methods. The EBV load in the peripheral blood mononuclear cells (PBMCs) from 19 patients receiving methotrexate, 68 patients receiving infliximab, and 48 patients receiving etanercept was monitored for durations ranging from 6 months to 5 years using a real-time polymerase chain reaction assay previously developed for that purpose. The effect of treatment duration on EBV load and the link between the Disease Activity Score in 28 joints and EBV load were analyzed by generalized estimating equations. Results. Methotrexate tended to decrease EBV load over time, but this did not reach significance. Tumor necrosis factor ␣ (TNF␣) inhibitors did not significantly modify EBV load over time. Finally, high disease activity was significantly associated with high EBV load. Conclusion. Long-term usage of methotrexate or TNF␣ inhibitors in patients with RA does not significantly influence EBV load in PBMCs.

We evaluated the use of capillary blood samples stored on filter papers for diagnosis of dengue virus infection. Venous and capillary blood samples were collected from 130 patients suspected of having dengue fever. We compared the performances of standard reference methods using capillary blood samples absorbed onto filter papers versus venous blood samples. The resulting sensitivity, specificity, and positive predictive value of tests performed on filter paper compared to those performed on venous blood samples were 81.6% (62/76; 95% confidence interval [CI], 74.9% to 88.3%), 90.7% (49/54; 95% CI, 85.7% to 95.7%), and 92.5% (62/67; 95% CI, 86.2% to 98.8%), respectively. During the acute phase of dengue virus infection (day 1 to day 4), the tests performed on capillary blood samples had a sensitivity of 88.5% (95% CI, 82.0% to 95.0%) and a specificity of 93.8% (95% CI, 88.9% to 98.7%). During the convalescent phase of infection, this method allowed the viral serotype to be determined for 4 of 15 (27%) dengue virus-infected patients for whom virological diagnosis using venous samples was negative. Capillary blood samples could therefore be a good alternative for the diagnosis of dengue virus infection in tropical areas. Indeed, these samples are convenient for storage and transport without the need for a cold chain and simplify the collection of samples from children. Moreover, our results suggest that viral particles persist longer in capillary blood than in peripheral blood. Analysis of the viability of viral particles under these conditions may give new insights into the physiopathology of dengue virus infection and the transmission of dengue virus during outbreaks.

On 20 April 2017, an outbreak of histamine food poisoning occurred in a French military unit located near Paris. A total of 40 cases were identified (attack rate: 16.6%). We conducted a case–control study on 31 cases and 63 controls. Multivariate analysis pointed to cooked yellowfin tuna fillet as the very likely source of food poisoning (odds ratio = 156.8; 95% confidence interval: 18.4–1,338.4). The fresh yellowfin tuna was from Reunion Island and was supplied vacuum-sealed and packed with ice at the principal food market of Paris. No cold chain issues could be established in the upstream and downstream supply chains. Histamine concentration was found to be 1,720 mg/kg in leftover raw tuna, and 3,720 mg/kg in control cooked tuna, well above the threshold limit values defined by European regulations (200 mg/kg). The presence of Klebsiella variicola and Pantoea agglomerans, microorganisms of the Enterobacterales order that have been reported to produce histamine, was confirmed in the leftover raw tuna. This type of food poisoning is rarely recognised and confirmed. We describe the outbreak to highlight the specific key points of this type of investigation.

Fibrinolytic therapy (FT) during out-of-hospital cardiac arrest (OHCA) has been studied in several trials, but they have produced unsatisfactory results even in the most recent Thrombolysis in Cardiac Arrest (TROICA) study. This study aimed to assess the impact of FT provided by an out-of-hospital emergency physician on the immediate prognosis of patients with OHCA. We performed a retrospective study in which the primary endpoint was survival to hospital admission. Among 5,102 patients with OHCA in Paris and the suburban area who received medical care from the Fire Brigade of Paris, 1,261 met the following inclusion criteria: age above 18 years with non-traumatic OHCA. Among 107 patients who received FT, 51 (47.7%) survived to hospital admission whereas 272 out of 1,154 (23.6%) patients who did not receive FT survived to hospital admission. A matching process based on a propensity score used to equalise potential prognosis factors in both groups demonstrated that FT was associated with more frequent survival to hospital admission (OR adjusted: 1.7; CI 95% [1.09-2.68]). This result was observed particularly in patients who were not initially shocked by automatic electrical defibrillator (AED) (OR(a) = 3.61; CI 95% [1.88-6.96]). This study showed that fibrinolysis was associated with improved survival to hospital admission, after performing a propensity analysis. FT may be beneficial in out-of-hospital arrest patients. However, any conclusions drawn are limited by the retrospective nature of the study.