ABSTRACT Neutralizing antibody titers and binding antibody levels are considered correlates of protection against severe SARS-CoV-2 infection. The clinical utility of serology should be reevaluated in light of the emergence of escape variants, as commercial antibody-binding assays have not been adapted to the virus’ antigenic evolution. We compared anti-SARS-CoV-2 antibody titers in four quantitative serological tests based on variable ancestral spike antigens (three in-house ELISAs and the prototype VIDAS SARS-CoV-2 IgG QUANT assay) and neutralization assays against the pseudotyped Wuhan, BA.2, BA.4/5, BQ.1.1, and XBB.1.1 viruses in a cohort of 100 patients infected in 2020 or during the Omicron waves. Binding antibody levels correlated well with neutralizing antibody titers for Wuhan, BA.2, and BA.4/5, but the association decreased for BQ.1.1 and XBB.1 (for the VIDAS assay, Spearman’s correlation was 0.82 [95% CI 0.74–0.88] and 0.61 [0.46–0.72] for BA.2 and XBB.1, respectively). In 15% of patients with no neutralizing antibodies against XBB.1, the VIDAS assay still yielded binding antibody levels ranging from 74 to 7,652 binding antibody units/mL. Using an adjusted threshold based on receiver operating characteristic (ROC) curve analysis, the specificity of neutralizing antibody detection increased from 0.15 (95% CI 0.02–0.45) and 0.17 (0.04–0.41) to 0.92 (0.64–1.00) and 0.83 (0.59–0.96) against BQ.1.1 and XBB.1, respectively. Serological tests based on receptor-binding domain antigens from the ancestral virus fail to predict neutralizing activity against the latest circulating Omicron variants. Adapting serological tests may improve their clinical utility in immunocompromised patients. IMPORTANCE Anti-SARS-CoV-2 serology was developed in 2020 in response to the COVID-19 pandemic to diagnose SARS-CoV-2 infection and monitor an individual’s immunity following natural infection or vaccination. Given the relationship between neutralizing antibody titers and protection against severe infection, many studies have evaluated the correlation between serology tests and neutralization assays in the pre-Omicron era. An important potential clinical use of serology, which explores binding antibodies, is estimating an individual’s level of protection against new infection, particularly in immunosuppressed individuals and those at risk of severe COVID. However, in the Omicron era, as new viruses evade the immunity induced by previous infections and vaccination, the correlation between binding antibody levels determined by serological assays developed from ancestral antigens and neutralizing antibody titers against new viruses should be re-examined in order to determine whether these assays should be optimized by adapting antigens to the circulating SARS-CoV-2 strains.

Objectives: Prevention strategies implemented by hospitals to reduce nosocomial transmission of SARS-CoV-2 sometimes failed. Our aim was to determine the risk factors for nosocomial COVID-19.Patients and methods: A case-control study was conducted (September 1, 2020-January 31, 2021) with adult patients hospitalized in medical or surgical units. Infants or patients hospitalized in ICU were excluded. Cases were patients with nosocomial COVID-19 (clinical symptoms and RT-PCR + for SARS-CoV-2 or RT-PCR + for SARS-CoV-2 with Ct <= 28 more than 5 days after admission); controls were patients without infection (RT-PCR- for SARS-CoV-2 > 5 days after admission). They were matched according to length of stay before diagnosis and period of admission. Analyses were performed with a conditional logistic regression.Results: A total of 281 cases and 441 controls were included. In the bivariate analysis, cases were older (OR per 10 years: 1.22; 95%CI [1.10;1.36]), had more often shared a room (OR: 1.74; 95%CI [1.25;2.43]) or a risk factor for severe COVID-19 (OR: 1.94; 95%CI [1.09;3.45]), were more often hospitalized in medical units [OR: 1.59; 95%CI [1.12;2.25]), had higher exposure to contagious health care workers (HCW; OR per 1person-day: 1.12; 95%CI [1.08;1.17]) and patients (OR per 1 person-day: 1.11; 95%CI [1.08;1.14]) than controls. In an adjusted model, risk factors for nosocomial COVID-19 were exposure to contagious HCW (aOR per 1person-day: 1.08; 95%CI [1.03;1.14]) and to contagious patients (aOR per 1person-day: 1.10; 95%CI [1.07;1.13]).Conclusions: Exposure to contagious professionals and patients are the main risk factors for nosocomial COVID-19.

Background COVID-19 severity is mainly related to lung impairment. However, preexisting patient characteristics and biomarkers at admission associated with this event are not precisely known.Methods We report 205 patients admitted for a proven COVID-19 in our institution between March 7 and April 22, 2020, particularly their comorbidities, respiratory severity, immune profile, and metabolic profile.Findings Median age was 70 years [interquartile range (IQR) 25-75: 60;79]; 115 (56·1%) patients were men. Oxygen supplementation of >2L/min was required in 107 patients (52·2%) after a median time of 8 days [IQR: 6;10] after the first symptoms; 67 (32·7%) patients were admitted to the intensive care unit (ICU), almost exclusively due to severe hypoxia. Patients requiring >2L/min oxygen therapy and/or ICU admission were older and more frequently males, with a significantly higher body mass index (BMI), a significantly higher total cholesterol (TC) / HDL cholesterol ratio, and higher triglycerides. They also had higher plasma levels of C-reactive protein (CRP) and interleukin 6 (IL-6); IL-6 >20 ng/L and CRP >70 mg/L were significantly associated with ICU admission and/or (for patients with a decision of limitation of life-support therapy) death. Higher BMI and TC/HDL-c ratio were associated with higher CRP and IL-6 levels. Steroid therapy was performed in 61 patients; while its clinical impact was inconclusive due to heterogeneous situations, IL-6 levels decreased significantly more in these patients.Interpretation Severe COVID-19 mostly relates to late-onset pneumonia associated with preexisting metabolic syndrome markers and a surge in inflammatory markers, allowing the early identification of at-risk patients.Funding This work was supported by Foundation University of Grenoble Alpes.### Competing Interest StatementThe authors have declared no competing interest.### Funding StatementThis work was supported by the Foundation University of Grenoble Alpes and Foundation Air Liquide.### Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:This study was conducted in accordance with the French legislation on the retrospective use of healthcare data, and ethical approval was given by the Clinical Research Direction of the Centre Hospitalier Universitaire Grenoble-Alpes. The BIOMARCOVID project is a research project that does not involve the human being and whose controller is the Centre Hospitalier Grenoble Alpes. This research has been registered in accordance with French regulations and meets the requirements of the National Commission for Information Technology and Civil Liberties (CNIL La Commission Nationale de l'Informatique et des Libertes) reference methodology 004.I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesAll data produced in the present study are available upon reasonable request to the authors

PREDIMED, Clinical Data Warehouse of Grenoble Alps University Hospital, is currently participating in daily COVID-19 epidemic follow-up via spatial and chronological analysis of geographical maps. This monitoring is aimed for cluster detection and vulnerable population discovery. Our real-time geographical representations allow us to track the epidemic both inside and outside the hospital.

Real-time PCR plays a key role in the diagnosis of viral infections. Multiple kits can detect or quantify genomes of various viruses with the same thermocycling program. Detection of RNA viruses includes an additional step of reverse transcription and challenge their detection in a single run with DNA viruses. We investigated the analytical performance of HSV-1, HSV-2 and VZV DNA quantification with Altona RealStar® PCR kits using the RT-PCR program for RNA viruses instead of the PCR program for DNA viruses. For each three viruses, Bland-Altman distribution did not show differences between both programs, and quantification curves generated with both thermocycling programs confirmed high correlation (R2 ≥ 0.9983). Detection of low viral load samples was evaluated, on 10-times repeat-test. All replicate samples were detected with both thermocycling programs and were quantified at similar viral loads (bias in log10 copies/mL: +0.05 (HSV-1), -0.01 (HSV-2) and +0.25 (VZV)). This confirms the feasibility of using the RT-PCR thermocycling program to detect and quantify the genome of RNA and DNA viruses in a single run.

Studies analyzing the persistence of protective immunity after SARS-CoV-2 infection are crucial to better understand the future dynamics of Covid-19 pandemic. We read with interest the results of Thangaraj et al.1Thangaraj J.W.V. Kumar M.S. Kumar C.G. et al.Persistence of humoral immune response to SARS-CoV-2 up to 7 months post-infection: cross-sectional study, South India, 2020-21.J Infect. 2021; 83: 381-412Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar regarding the evolution over time of anti-SARS-CoV-2 antibodies up to 7 months after an infection. Following 755 individuals, they observed a clear waning of anti-nucleocapside and anti-spike antibodies, but the persistence of neutralizing, anti-receptor binding domain (RBD) antibodies (NAb) in 86.2% of participants 181–232 days after RT-PCR diagnosis; those with more severe Covid-19 had higher NAb titres. We conducted a follow-up of NAb titres 6 months (217 ± 19 days) and up to 1 year (377 ± 12 days) after a RT-PCR proven infection in 67 patients, infected between March and April 2020. Quantitative detection of SARS-CoV-2 antibodies targeting S1-RBD was determined by the Siemens SARS-CoV-2 IgG (sCOVG) assay on the Atellica IM platform (Siemens, Munich, Germany). Neutralizing antibody quantification was performed according to the previously published protocol,2Bal A. Brengel-Pesce K. Gaymard A. et al.Clinical and laboratory characteristics of symptomatic healthcare workers with suspected Covid-19: a prospective cohort study.Sci Rep. 2021; 11: 14977Crossref PubMed Scopus (11) Google Scholar based on a pseudotyped virus entry assay using a luciferase reporter gene. Pseudo-virus displaying full-length SARS-CoV-2 spike protein (derived from USA-WA1/2020 strain) was produced in HEK293T cells and used to infect HeLa-ACE2 cells. The result from this assay is expressed as the serum dilution required to reduce infection by 50% (ID50). The study was approved by the Comité de Protection des Personnes Sud-Est I on 20 August 2020 (Ref. 2020–84). Mean age at positive RT-PCR was 59.8 ± 12 years; 42 (67.5%) of patients were males. Regarding Covid-19 severity, 17 (25.4%) individuals did not require oxygen supplementation, 17 (25.4%) required oxygen at a maximum of 2 L/min, and 33 (49.2%) required more than 2 L/min oxygen, among whom 29 were admitted to an intensive care unit. Dexamethasone was used in 20 of these 33 patients during the acute Covid-19 phase, all in patients admitted to ICU. At the first sample (N = 67), median Atellica serology titre was 11.0 U/mL [IQR: 5–27]. It was correlated with age (p< 0.001, rho= 0.411) and severity (suppl. Table 1). Among those who required oxygen supplementation > 2 L/min, there was no significant difference according to steroid use (suppl Table 1). At this same time, the median ID50 NAb titre was 166 [IQR: 87–372]; two patients had no detectable NAb activity. Neutralization titres were correlated with age (p = 0.014, rho= 0.302) and severity (no oxygen vs. oxygen > 2 L/min: p = 0.020) (suppl. Table 1). Among individuals requiring oxygen supplementation > 2 L/min, there was no significant difference according to steroid use, although there was a trend toward lower titres for those who received steroids (suppl. Table 1). A positive correlation was observed between SARS-CoV-2 IgG antibodies as detected by the Atellica serology assay and the NAb titres (p< 0.001, rho= 0.455]. At the second sample (N = 52), 16 participants had received a first dose of the Covid-19 vaccine (Pfizer/BioNTech™, Moderna™, or AstraZeneca™) between the two samples. Median Atellica serology titre was 12.9 U/mL [4.8–85.1], with striking differences according to the vaccine status. Indeed, the median titre for those vaccinated before the second sample was 750.0 U/mL [16.2–750] vs. 6.9 U/mL [3.4–15.4] for unvaccinated subjects (p< 0.001) (Fig. 1); the Atellica serology titres remained stable between the two dates for unvaccinated individuals but greatly increased among the vaccinated. Median ID50 neutralizing titres was 268 [177–545], with the same difference as above according to vaccine status. Indeed, the median ID50 titre for patients vaccinated between the two samples was 742 [269–1528] vs 237 [122–320] for unvaccinated subjects (p< 0.001) (Fig. 1). This difference was observed throughout the different severity groups (Fig. 2). There was no difference in titre according to the initial use of steroids (Suppl. Table 1).Fig. 2Neutralizing antibody titres at the two sampling dates according to severity, steroid use, and (for the second date) vaccination (black triangles) or not (white triangles). (The two samples with no detectable NAbs are figured above the X axis with an arrow).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Correlates of protection for Covid-19 are not completely established. However, the presence of NAb is associated with protection against many viral infections, and recent studies showed that the risk of SARS-CoV-2 reinfection was correlated with the NAb titres.3Bergwerk M. Gonen T. Lustig Y. et al.Covid-19 breakthrough infections in vaccinated health care workers.N Engl J Med. 2021; (Under press): 1474-1484Crossref PubMed Scopus (905) Google Scholar NAb response have therefore been particularly explored, mostly in the first months after SARS-CoV-2 infection, with somehow contrasting results. We observed in our cohort that nearly all patients (65/67) had detectable NAb titres 7 months after their symptomatic SARS-CoV-2 infection, and that titres were stable between 6 months and 1 year (as measured by both EIA and neutralization assay). Relatively few studies have yet assessed NAb titers 1 year after infection; in a cohort of 73 subjects,4Xiang T. Liang B. Fang Y. et al.Declining levels of neutralizing antibodies against SARS-CoV-2 in convalescent Covid-19 patients one year post symptom onset.Front Immunol. 2021; 12708523Crossref Scopus (60) Google Scholar only 43% of individuals had detectable NAb titres after 1 year (vs 98% of 25 subjects sampled at months 5,6); in contrast, in a cohort of 620 individuals (58% inpatients and 42% outpatients),5Wisnivesky J.P. Stone K. Bagiella E. et al.Long-term persistence of neutralizing antibodies to SARS-CoV-2 following infection.J Gen Intern Med. 2021; 36: 3289-3291Crossref PubMed Scopus (10) Google Scholar the proportion with detectable NAb was high (80 to 90%) at 1 month and stable at 13 months (70–85%); in another recent study,6Haveri A. Ekstrom N. Solastie A. et al.Persistence of neutralizing antibodies a year after SARS-CoV-2 infection in humans.Eur J Immunol. 2021; https://doi.org/10.1002/eji.202149535Crossref PubMed Scopus (53) Google Scholar 97% of 367 patients had detectable NAb against initial SARS-CoV-2 strain at 13 months. In these different studies, those with more severe Covid-19 had higher NAb titres, as observed in our participants. We did not observed a significant influence of steroid therapy at the acute phase on the long-term NAb titres; this had already been observed during earlier follow-up (< 1 month).7Muhlemann B. Thibeault C. Hillus D. et al.Impact of dexamethasone on SARS-CoV-2 concentration kinetics and antibody response in hospitalized Covid-19 patients: results from a prospective observational study.Clin Microbiol Infect. 2021; 27 (Under press): 1520.e7-1520.e10Abstract Full Text Full Text PDF Scopus (10) Google Scholar Although unintended when we designed the study, we observed the expected booster effect of the vaccine dose. This so-called "hybrid immunity" has been observed in previous studies,8Crotty S. Hybrid immunity.Science. 2021; 372: 1392-1393Crossref Scopus (162) Google Scholar leading the French health authorities to recommend in early 2021 that subjects with a past SARS-CoV-2 infection should receive only one instead of two doses of the mRNA-based vaccine or AstraZeneca™ ChAd-based vaccine.9Haute Autoristé de Santé. [Vaccine strategy against SARS-CoV-2 - vaccination of people with a past history of Covid-19]. https://wwwhas-santefr/jcms/p_3237355/fr/strategie-de-vaccination-contre-le-sars-cov-2-vaccination-des-personnes-ayant-un-antecedent-de-Covid-19-synthese. 2021;consulted August 11th 2021.Google Scholar Our study has several limitations, the first being its relatively small population size. Moreover, we did not assess the neutralizing potency of NAb against the Delta variant, which is less efficiently targeted by NAb induced by an infection with the viral strains circulating in 2020. Indeed, a recent pooled analysis.10Chen X. Chen Z. Azman A.S. et al.Neutralizing antibodies against SARS-CoV-2 variants induced by natural infection or vaccination: a systematic review and pooled meta-analysis.Clin Infect Dis. 2021; (Under press)https://doi.org/10.1093/cid/ciab646Crossref Scopus (62) Google Scholarconcluded that the SARS-CoV-2 lineages Beta, Gamma, and Delta were less sensitive to NAb induced by a previous (2020) infection, with an average 4.1-fold (95% CI: 3.6–4.7), 1.8-fold (1.4–2.4), and 3.2-fold (2.4–4.1) reduction in IC50 titres. Olivier Epaulard: Visualization, Writing – original draft. Marlyse Buisson: Writing – review & editing. Benjamin Nemoz: Visualization, Writing – original draft. Marion Le Maréchal: Visualization, Writing – original draft. Nicolas Terzi: Writing – review & editing. Jean-François Payen: Writing – review & editing. Marie Froidure: Writing – review & editing. Myriam Blanc: Writing – review & editing. Anne-Laure Mounayar: Writing – review & editing. Fanny Quénard: Writing – review & editing. Isabelle Pierre: . Patricia Pavese: Writing – review & editing. Raphaele Germi: Writing – review & editing. Laurence Grossi: Writing – review & editing. Sylvie Larrat: Writing – review & editing. Pascal Poignard: Visualization, Writing – review & editing. Julien Lupo: Visualization, Writing – original draft. Siemens Healthineers for Atellica sCOVG reagents offered free of charge. This work was supported by the Direction à la Recherche Clinique et à l'Innovation du CHU Grenoble Alpes, Grenoble, France. This funding source had not involvement in study design, in the collection, analysis and interpretation of data, in the writing of the report, and in the decision to submit the article for publication.

Robust antigen point-of-care SARS-CoV-2 tests have been proposed as an efficient tool to address the COVID-19 pandemic. This requirement was raised after acknowledging the constraints that are brought by molecular biology. However, worldwide markets have been flooded with cheap and potentially underperforming lateral flow assays. Herein we retrospectively compared the overall performance of five qualitative rapid antigen SARS-CoV-2 assays and one quantitative automated test on 239 clinical swabs. While the overall sensitivity and specificity are relatively similar for all tests, concordance with molecular based methods varies, ranging from 75,7% to 83,3% among evaluated tests. Sensitivity is greatly improved when considering patients with higher viral excretion (Ct≤33), proving that antigen tests accurately distinguish infectious patients from viral shedding. These results should be taken into consideration by clinicians involved in patient triage and management, as well as by national authorities in public health strategies and for mass campaign approaches.

A 96-year-old woman was admitted to the emergency department with generalized epileptic seizures and fever followed by left hemiparesis. Two days before admission, she had developed anosmia, dysgeusia,1 and behavioral dysexecutive syndrome. No respiratory symptoms were present or reported. Whereas nasopharyngeal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription PCR was negative, chest CT scan showed several lung areas of ground-glass opacity and intralobular cross-links, suggestive of SARS-CoV-2 infection.2 CSF analysis yielded 8 leukocytes/mm3 (75% polymorphonuclear neutrophilic cells) and was negative for SARS-CoV-2 PCR. Brain MRI revealed hyperintensity of the olfactory tracts on T2 fluid-attenuated inversion recovery and diffusion-weighted imaging (figure). Ten days after the admission, SARS-CoV-2 serology returned positive, thus supporting a SARS-CoV-2–related encephalitis.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for coronavirus disease 2019 (COVID-19) led to the death of thousands of people around the world.1 Neurologic manifestations are not much specific apart from acute anosmia, and postinfectious manifestation data are missing.2 We described the cases of 2 patients exhibiting demyelinating form of Guillain-Barré syndrome (GBS) and summarized neurologic manifestations and investigations results in table 1.

The coronavirus disease 2019 (COVID-19) was first reported in the city of Wuhan, China. The disease rapidly spread to the rest of China, to Southern-East Asia, then to Europe, America, and on to the rest of the world. COVID-19 is associated with a betacoronavirus named SARS-CoV-2. The virus penetrates the organism through the respiratory tract, conveyed by contaminated droplets. The main cell receptor targeted is the surface-bound ACE-2. As of the 26th July 2020, 15,200,000 COVID-19 cases and 650,000 deaths were reported worldwide. The mortality rate is estimated between 1.3 and 18.3%. The reproductive rate without any public health intervention is estimated around 4-5.1 in France. Most hospitalized patients for COVID-19 present respiratory symptoms, which in some cases is associated with fever. Up to 86% of admissions to ICU are related to acute respiratory failure. To date, no anti-viral therapy has proven its efficacy considering randomized trials. Only immunomodulatory treatments such as corticosteroids have shown to cause significant improvement in patient outcome.

L’exploration du microbiote respiratoire dans le cadre du suivi des patients atteints de mucoviscidose necessite a ce jour la mise en culture de prelevements respiratoires ou l’utilisation de PCR selectives. Ces techniques presentent d’importantes limitations et ne sont pas adaptees a une exploration pan-microbienne qui serait necessaire pour mieux comprendre les mecanismes physiopathologiques a l’œuvre dans cette pathologie et dans son evolution. Nous presentons ici une approche novatrice pour l’exploration de ce microbiote respiratoire et les premiers essais realises au sein du laboratoire pour la caracteriser. Cette methode est basee sur le sequencage de nouvelle generation (NGS) des echantillons apres un enrichissement par capture semi-ciblee en milieu liquide. Cette capture est realisee par hybridation sur sondes des acides nucleiques d’interet. La realisation de cet enrichissement a necessite la selection de cibles d’interet pour la fabrication d’une puce de capture pan-microbienne. Nous montrons dans une deuxieme partie de ce travail les resultats obtenus a l’aide de cette puce DB-Chip pour la detection de bacteries, virus, champignons et parasites au sein d’echantillons artificiels. Cette approche retrouve les pathogenes attendus sur les prelevements dont la composition est connue. L’identification des micro-organismes est possible jusqu’au rang d’espece pour les bacteries et les virus. Les performances de notre puce de capture ne sont pas inferieures a celles obtenues par d’autres equipes avec des approches axees sur un seul regne (viral ou bacterien). Notre approche est prometteuse mais necessite des ajustements pour son utilisation en clinique.

Treatment options for Hepatitis C infection have greatly improved with direct-acting antiviral (DAA) combinations achieving high cure rates. Nevertheless, the cost of this treatment is still high and access to treatment in many countries has been preferentially reserved for patients with more severe fibrosis (F3 and F4). In this French nationwide study, we investigated the epidemiological characteristics and genotype distribution of hepatitis C virus (HCV) in treatment-naive patients with METAVIR fibrosis stages between F0 and F2 in order to identify patient profiles that became eligible for unrestricted treatment in a second period. Between 2015 and 2016 we collected data from nine French university hospitals on a total of 584 HCV positive patients with absent, mild or moderate liver fibrosis. The most represented genotypes were genotype 1b (159/584; 27.2%), followed by genotype 1a (150/584; 25.7%); genotype 3 (87/584: 14.9%); genotype 4 (80/584; 13.7%). Among genotype 4: 4a was predominantly encountered with 22 patients (27.5% of genotype 4). Genotypes 1b and 1a are currently the most frequent virus types present in treatment-naive patients with mild fibrosis in France. They can be readily cured using the available DAA. Nevertheless, non-a/non-d genotype 4 is also frequent in this population and clinical data on the efficacy of DAA on these subtypes is missing. The GEMHEP is the French group for study and evaluation of viral hepatitis on a national scale. Data collection on epidemiological and molecular aspects of viral hepatitis is performed on a regular basis in all main French teaching hospitals and serves as a basis for surveillance of these infections. Analysis and trends are regularly published on behalf of the GEMHEP group. Data collection was performed retrospectively over the 2015-2016 period, covering nine main university hospitals in France. A total of 584 hepatitis C positive patients were included in this study. Genotyping of the circulating viruses showed a high prevalence of genotypes 1b and 1a in our population. The epidemiology of hepatitis C is slowly changing in France, particularly as a consequence of the rise of 'non-a non-d' genotype 4 viruses mainly originating from African populations. More data concerning treatment efficacy of these genotypes is needed in order to guide clinical care.

Purpose Since the early 2010s, deaths due to the use of new synthetic opioids (NSO) including fentanyl and its analogs have been increasing dramatically. As fentanyl analogs bear strong structural similarities, they can share common metabolites. In some clinical or forensic cases, it can be important to demonstrate the presence of both the metabolite and the parent product to confirm that the compound is responsible for the intoxication. Norcarfentanil is a common metabolite of carfentanil (NSO) and remifentanil (widely used in medical care). This article reported the investigation of norcarfentanil origin in three cases. Methods Comprehensive screenings were performed using gas chromatography coupled to mass spectrometry and liquid chromatography coupled to a diode array detection, whereas targeted screening of NSO were performed using liquid chromatography coupled to tandem mass spectrometry. Results Norcarfentanil was detected at concentrations ranging from 0.05 to 15.8 ng/mL in plasma and from 8.8 to 1820 ng/mL in urine, but carfentanil was detected in two out of the three cases. The presence of norcarfentanil has been supposed to be due to the treatment with remifentanil during the medical care of the patient. Conclusions In the first two cases, norcarfentanil was present as the metabolite of carfentanil, whereas in the last case, norcarfentanil was the metabolite of remifentanil. Without the identification of remifentanil, confusion could occur, and norcarfentanil could be attributed to carfentanil misuse.

Direct-acting antiviral (DAA) drug performances depend on the viral genotype. So international recommendations give typing of the virus a prerequisite for treatment choice and patient management. Commercially available HCV genotyping kits are scarce and this analysis is often in-house using tedious PCRs and Sanger sequencing, leading to a lack of standardization. A newly commercialized HCV genotyping assay based on real-time PCR has been developed by Roche Diagnostics (Mannheim, Germany). We compared this new assay with our in-house PCRs -sequencing technique on 101 regular samples and 81 LiPA failures or low viral load samples. No genotype or 1a/1b subtype mismatch was observed. Two samples were misidentified at the subtype level without clinical impact. Three genotype 1b and two genotype 1a samples with low viral load could not be subtyped. Nevertheless, 13 (13%) samples from the regular panel and 35 (43%) from the more difficult-to-type panels failed to give results on first pass with the Roche kit. Failures were mostly associated with genotype 3 subtype a, with genotype 4 subtype non-a, or with viral loads <200 IU/mL (p = 0.0061). The workflow allowed a non-specialized technician to obtain results in less than 4 hours whereas 2 to 3 days and experienced staff were required with the in-house assay. In conclusion, the Roche cobas® HCV GT kit is easy and rapid to use and provides reliable results. The high rate of uninterpretable results particularly for low viral load samples and less frequent genotypes, and the absence of subtyping for non-genotype 1 could require sending complex samples to a specialized laboratory.

AimsTherapeutic drug monitoring (TDM) of infliximab (IFX) appears to be beneficial for patients with inflammatory bowel disease (IBD). However, the recommended target concentrations depend partly on the method used to quantify IFX. Since we recently developed a liquid chromatography–tandem mass spectrometry method to quantify IFX, we aimed to determine IFX trough concentrations (Cmin) associated with biological remission.MethodsWe retrospectively measured IFX Cmin in sera from 55 patients with IBD, on IFX maintenance therapy, and for whom demographic, biological and clinical data were collected from medical records. A threshold of IFX Cmin associated with biological remission (defined by C‐reactive protein < 5 mg l–1 and faecal calprotectin <150 μg g–1) was determined using receiver operating characteristics analysis.ResultsIFX Cmin ranged from <1 mg l–1 to 57.2 mg l–1. IFX Cmin were higher (P = 0.038) in patients with biological remission and a cut‐off of IFX Cmin set to 6.2 mg l–1 was associated with biological remission (sensitivity = 0.75, 95% confidence interval 0.58–0.75; specificity = 0.61, 95% confidence interval 0.39–0.83).ConclusionLiquid chromatography–tandem mass spectrometry measurement of IFX Cmin and the determination of a new threshold of IFX Cmin associated with biological remission are new steps towards IFX treatment personalization in patients with IBD.

Background: Adalimumab (ADA) and infliximab (IFX) are therapeutic monoclonal antibodies targeting tumor necrosis factor-alpha (TNFα). They are used to treat inflammatory diseases. Clinical trials have suggested that therapeutic drug monitoring for ADA or IFX could improve treatment response and cost effectiveness. However, ADA and IFX were quantified by ELISA in all these studies, and the discrepancies between the results obtained raise questions about their reliability. We describe here the validation of a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of ADA and IFX in human samples. Methods: Full-length antibodies labeled with stable isotopes were added to plasma samples as an internal standard. Samples were then prepared using Mass Spectrometry Immunoassay followed by trypsin digestion before ADA and IFX quantification by LC-MS/MS. ADA and IFX were quantified in serum from patients treated with ADA (n = 21) or IFX (n = 22), and the concentrations obtained were compared with those obtained with a commercial ELISA kit. Results: The chromatography run lasted 8.6 minutes, and the quantification range was 1–26 mg/L. The method was reproducible, repeatable, and accurate. For both levels of internal quality control, for ADA and IFX, interday and intraday coefficients of variation and accuracies were all within 15%, in accordance with FDA recommendations. No significant cross-contamination effect was noted. Good agreement was found between LC-MS/MS and ELISA results, for both ADA and IFX. Conclusions: This LC-MS/MS method can be used for the quantification of ADA and IFX in a single analytical run and for the optimization of LC-MS/MS resource use in clinical pharmacology laboratories.