Paul-Louis Woerther

• Professor (Associate) at Hôpital Henri Mondor (Hôpitaux Universitaires Henri Mondor)

Objectives MSSA remains the leading cause of infective endocarditis (IE) and is responsible for significant mortality. While clinical factors tied to mortality are well documented, possible contributing strain-specific characteristics have not been extensively explored. This study investigates MSSA phenotypic and genotypic characteristics and medic...

Background Antimicrobial stewardship (AMS) for ventilator-associated pneumonia (VAP) in carriers of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) presents significant challenges. The abundance of ESBL-E rectal carriage has emerged as a potentially valuable tool for predicting ESBL-E-related VAP. Methods This single-center, retr...

Background Respiratory infection may account for 30% of acute chest syndrome (ACS) aetiologies. However, antimicrobials are routinely prescribed, and de-escalation and/or discontinuation are challenging. Multiplex Polymerase Chain Reaction (mPCR) with an enlarged respiratory panel might support antimicrobial stewardship, and procalcitonin (PCT) mea...

Objectives Lymphadenopathy is a classical manifestation of systemic lupus erythematosus (SLE) flare, occurring in approximately half of patients during the course of the disease. Lymphadenopathy in SLE is frequently associated with fever. Microbial infection may play a role in SLE onset and flares. Objectives of this study were to describe lymphade...

Background Antimicrobial stewardship (AMS) for ventilator-associated pneumonia (VAP) or ventilated hospital-acquired pneumonia (vHAP) in extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) carriers is challenging. BioFire® FilmArray® Pneumonia plus Panel (mPCR) can detect bacteria and antibiotic resistance genes, including bla CTX-M ,...

Severe coronavirus disease 2019 (COVID‐19) is related to dysregulated immune responses. We aimed to explore the effect of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) variants on the immune response by nasopharyngeal transcriptomic in critically‐ill patients. This prospective monocentric study included COVID‐19 patients requiring in...

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) exposes the patient to infectious complications related to the cannulas or the site of insertion. The aim of the current study was to investigate and compare the prevalence of cannula and membrane oxygenators colonization using three different methods: microbiological culture, scanning elec...

Enterococcus faecium, a common resident of the human gastrointestinal tract, is also a major pathogen. Prompt initiation of appropriate treatment is essential to improve patient outcome in disseminated E. faecium infections. However, ampicillin resistance is frequent in this species, rendering treatment difficult. We used a comprehensive approach,...

Cutibacterium avidum is an emerging causative agent of orthopedic device-related infections (ODRIs). There are no guidelines for the antimicrobial treatment of C. avidum ODRI, but oral rifampin is frequently used in combination with a fluoroquinolone following intravenous antibiotics. We describe the in vivo emergence of combined resistance to rifa...

Hepatitis of undetermined origin can be caused by a wide variety of pathogens, sometimes emerging pathogens. We report the discovery, by means of routine shotgun metagenomics, of a new virus belonging to the family Circoviridae, genus Circovirus, in a patient in France who had acute hepatitis of unknown origin.

The advent of high-throughput sequencing in clinical microbiology is opening the way to new diagnostic and prognostic approaches in infectious diseases. Detection, identification and characterisation of pathogenic microorganisms are essential steps in diagnosis and implementation of appropriate antimicrobial therapy. However, standard methods of mi...

Background/ objective: Our aim was to compare the prevalence of biofilm formation on antibiotic-impregnated (AIC) versus standard (SC) external ventricular drainage (EVD) catheters. Methods: From March 2018 to November 2020, all consecutive EVD catheters inserted in adult patients were included. After removal, EVD catheters were analyzed under s...

Purpose of review: Managing antimicrobial therapy in patients with complicated skin and soft tissue infections (SSTI) constitutes a growing challenge due to the wide spectrum of potential pathogens and resistance phenotypes. Today, microbiological documentation relies on cultural methods. This review summarizes the available evidence regarding the...

Objectives To evaluate the performances of the QMAC-dRAST GN (Gram-negative) kit for rapid antimicrobial sensitivity testing (AST) and two other methods, directly on positive blood-culture broth (PBCB), by comparison with a reference method: the MicroScan method based on broth microdilution on colonies isolated on PBCB subculture. Methods In total...

Background β-lactams are the main antibiotics used against wild-type AmpC-producing Enterobacterales (wtAE). However, they may fail or select AmpC-overproducing mutants. Our aim was to assess factors associated with clinical failure of β-lactams in the treatment of wtAE infection. Methods From September 2017 to December 2020, we prospectively incl...

Objectives EUCAST changed the definition of the ‘intermediate’ (I) category in 2019, now defined as ‘susceptible, increased exposure’. This new definition could lead to an increased prescription of antibiotics still reported as ‘S’, compared with those now reported as ‘I’. The objective of this study was to evaluate the influence of this definition...

Purpose: Post-operative vasoplegic syndrome is a dreaded complication in infective endocarditis (IE). Methods and results: This retrospective study included 166 consecutive patients referred to cardiac surgery for non-shocked IE. Post-operative vasoplegic syndrome was defined as a persistent hypotension (mean blood pressure < 65 mmHg) refractory...

Background: Diagnosis of co/superinfection in patients with Acute Respiratory Distress Syndrome (ARDS) is challenging. The FilmArray Pneumonia plus Panel (bioMérieux, France), a new rapid multiplex Polymerase Chain Reaction (mPCR), has never been assessed on a blinded protected telescope catheter (PTC) samples, a very common diagnostic tool in pat...

This study aimed to compare the chromosomal beta-lactamase from Pectobacterium versatile , PEC-1, with the well-known and globally distributed TEM-1 in terms of genetic and functional properties. Despite the similarities between the enzymes, we obtained no definitive proof of gene transfer for the emergence of bla PEC-1 from bla TEM-1 .

BACKGROUND Asymptomatic faecal carriage of Clostridioides difficile has been widely evaluated but the prevalence across a wide range of clinical departments and related risk factors are not well-described. The objectives of the PORTADIFF study were to evaluate the prevalence and identifying risk factors leading to asymptomatic carriage of both toxi...

Bacteriological diagnosis is traditionally based on culture. However, this method may be limited by the difficulty of cultivating certain species or by prior exposure to antibiotics, which justifies the resort to molecular methods, such as Sanger sequencing of the 16S rRNA gene (Sanger 16S). Recently, shotgun metagenomics (SMg) has emerged as a pow...

Background Extended spectrum β-lactamase-producing Enterobacterales (ESBL-E) represent a major threat to public health. Little is known on their potential for sexual transmission. Methods We recruited individuals at a sexually transmitted infection and HIV-outpatient clinic in Paris, France in whom we evaluated the prevalence of ESBL-E intestinal...

We report a case of meningoencephalitis due to Nocardia cyriacigeorgica diagnosed with metagenomics, while all the standard methods were negative. This diagnosis made adaptation of antimicrobial treatment possible and led to the discovery of a rare, acquired immunodeficiency syndrome.

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support leads to complex pharmacokinetic alterations, whereas adequate drug dosing is paramount for efficacy and absence of toxicity in critically ill patients. Amikacin is a major antibiotic used in nosocomial sepsis, especially for these patients. We aimed to describe amikacin pharmacok...

Idiopathic multicentric Castleman disease (iMCD) is a lymphoproliferative disease of unknown etiology. Deciphering mechanisms involved in CD pathogenesis may help improving patients’ care. Six cases of stereotyped sub-diaphragmatic iMCD affecting lower limb-draining areas and associated with severe and often ulcerative lower extremity chronic derma...

To assess the need for prolonged incubation of blood culture bottles beyond five days for the diagnosis of infectious endocarditis (IE), we conducted a retrospective cohort study of 6109 sets of two blood culture bottles involving 1211 patients admitted to the Henri Mondor University Hospital for suspicion of IE between 1 January 2016 and 31 Decemb...

An amendment to this paper has been published and can be accessed via the original article.

Necrotizing soft tissue infections (NSTIs) are rare life-threatening bacterial infections characterized by an extensive necrosis of skin and subcutaneous tissues. Initial urgent management of NSTIs relies on broad-spectrum antibiotic therapy, rapid surgical debridement of all infected tissues and, when present, treatment of associated organ failure...

Introduction En septembre 2018, le CA-SFM a modifié la définition de la catégorie clinique « intermédiaire » conformément aux recommandations de l’EUCAST, signifiant désormais « sensible à forte posologie ». Pour les infections à Pseudomonas aeruginosa (PA), les souches antérieurement rendues « sensible » pour les bêta-lactamines (BL) sont désormai...

Introduction L’endocardite infectieuse (EI) est une pathologie rare avec une létalité qui reste élevée malgré les progrès diagnostiques et thérapeutiques. Nous avons étudié l’apport des outils microbiologiques dont la biologie moléculaire dans la documentation des EI à hémocultures stériles. Matériels et méthodes Nous avons mené une étude observat...

Toxic epidermal necrolysis (TEN) is a rare but severe acute life‐threatening condition, mostly drug‐induced, and characterized by a massive apoptosis of keratinocytes.1 Among complications, bloodstream infections (BSI) due to opportunistic pathogenous bacteria represent a significant proportion of the mortality rate, despite the meticulous hygiene...

Clinical metagenomics (CMg) is the process of sequencing nucleic acid of clinical samples to obtain clinically relevant information such as the identification of microorganisms and their susceptibility to antimicrobials. Over the last decades, sequencing and bioinformatic solutions supporting CMg have much evolved and an increasing number of case r...

Fungal ball (FB) rhinosinusitis (RS) is the main type of non-invasive fungal RS. Despite positive direct examination (DE) of biopsies, culture remains negative in more than 60% of cases. The aim of the study was to evaluate the performance/efficacy of targeted metagenomics (TM) to analyze microbiota and mycobiota in FB and find microbial associatio...

Background: Escherichia coli is the leading cause of bloodstream infections, associated with a significant mortality. Recent genomic analyses revealed that few clonal lineages are involved in bloodstream infections and captured the emergence of some of them. However, data on within sequence type (ST) population genetic structure evolution are rare...

Context Today, infective endocarditis (IE) caused by E. faecalis represents 10% of all IE and is marked by its difficult management and the frequency of relapses. Although the precise reasons for that remain to be elucidated, the evolution of the culprit strain under selective pressure through microdiversification could be, at least in part, involv...

COVID-19 is characterized by respiratory symptoms of various severities, ranging from mild upper respiratory signs to acute respiratory failure/acute respiratory distress syndrome associated with a high mortality rate. However, the pathophysiology of the disease is largely unknown. Shotgun metagenomics from nasopharyngeal swabs were used to charact...

Temocillin is used for several years in some European countries but, only since 2015 in France. We assessed the susceptibility of Enterobacterales strains isolated from blood culture one year before (2014) and two years after (2017) its use in France. 1,387 strains were included by 17 clinical laboratories located throughout France: 363 in 2014 and...

For decades, the term “anti-anaerobic” has been commonly used to refer to antibiotics exhibiting activity against anaerobic bacteria, also designated as anaerobes. This term is used in various situations ranging from infections associated with well-identified pathogens like Clostridioides difficile, or Fusobacterium necrophorum in Lemierre’s syndro...

Surgical cutting guides are increasingly used for maxillofacial reconstruction. They are usually provided by laboratories. In recent years, surgical teams have published studies on the possibility of manufacturing their own cutting guides thanks to 3D printers. The object of this study is to analyze the impact of the sterilization on the surface of...

Introduction La gangrène de Fournier est une fasciite nécrosante (FN) péri anale, périnéale et génitale qui résulte d’une infection polymicrobienne. Dans la littérature, une cause urogénitale, digestive ou cutanée est souvent trouvée au diagnostic mais la recherche à moyen terme d’une porte d’entrée n’est pas rapportée. Matériel et méthodes Étude...

Background Data on incidence of ventilator-associated pneumonia (VAP) and invasive pulmonary aspergillosis in patients with severe SARS-CoV-2 infection are limited. Methods We conducted a monocenter retrospective study comparing the incidence of VAP and invasive aspergillosis between patients with COVID-19-related acute respiratory distress syndro...

The original article was updated to correct the co-author name Suhan Senova in author list. The details mentioned here are correct.

Introduction: The complexity of biofilms constitutes a therapeutic challenge and the antimicrobial susceptibility of fungal-bacterial biofilms remains poorly studied. The filamentous fungus Aspergillus fumigatus (Af) and the Gram-negative bacillus Stenotrophomonas maltophilia (Sm) can form biofilms and can be co-isolated from the airways of cystic...

The fosfomycin breakpoint using the disc diffusion method (DDM) changed in the 2019 CA-SFM/EUCASTguidelines v2 (24 mm versus 19 mm).We assessed its impact on categorization of Enterobacterales recovered from urine samples in emergency departments. A total of 7749 and 2348 strains were tested usingthe DDM and the broth microdilution method (BMD), re...

Objectives: Cerebral infections related to the presence of an intraparenchymal intracranial pressure transducer (ICPT) are rare. We assessed the incidence of ICPT-related infections and colonization using culture, molecular biology, and electron microscopy. Methods: All consecutive patients in a neurosurgical intensive care unit who had an ICPT...

Induction chemotherapy (7 + 3 regimen) remains the gold standard for patients with acute myeloid leukemia (AML) but is responsible for gut damage leading to several complications such as bloodstream infection (BSI). We aimed to investigate the impact of induction chemotherapy on the intestinal barrier of patients with AML and in wild-type mice. Nex...

Introduction Le diagnostic microbiologique repose principalement sur des méthodes de culture, de sérologies ou de PCR ciblées. Certaines maladies infectieuses restent néanmoins difficiles à diagnostiquer. La métagénomique clinique (MGC) est une technique de séquençage à haut débit permettant le diagnostic étiologique de processus infectieux, indépe...

We report a fatal case of measles inclusion-body encephalitis occurring in a woman from Romania with AIDS. After an extensive but unsuccessful diagnostic evaluation, a pan-pathogen shotgun metagenomic approach revealed a measles virus infection. We identified no mutations previously associated with neurovirulence.

Background The goal of this study was to assess risk factors of ventilator-associated pneumonia (VAP) and invasive pulmonary aspergillosis in patients with SARS-CoV-2 infection. Methods. We conducted a monocenter retrospective study comparing the prevalence of VAP and invasive aspergillosis between patients with COVID-19 related acute respiratory d...

We report the discovery of a new orthobunyavirus, Cristoli virus, by means of shotgun metagenomics. The virus was identified in an immunodepressed patient with fatal encephalitis. Full-length genome sequencing revealed high-level expression of a virulence factor, possibly explaining the severity of the infection. The patient's recent history sugges...

Gut microbiota composition influences the clinical benefit of immune checkpoints in patients with advanced cancer but mechanisms underlying this relationship remain unclear. Molecular mechanism whereby gut microbiota influences immune responses is mainly assigned to gut microbial metabolites. Short-chain fatty acids (SCFA) are produced in large amo...

Background High-throughput sequencing techniques are used to analyse the diversity of the respiratory microbiota in health and disease. Although extensive data are available regarding bacterial respiratory microbiota, its fungal component remains poorly studied. This is partly due to the technical issues associated with fungal metagenomics analyses...

Background : The prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) has globally increased and spread to the community. No clinical score is available to select carriers in whom these organisms can be empirically targeted at ICU admission. Methods : We prospectively assessed between 2009 and 2017 the prevalence o...

Objectives: The aim of the study was to characterize phenotypically and genotypically an uncommon mechanism of resistance to macrolides, lincosamides, and streptogramins (MLS) in a Streptococcus milleri group clinical isolate. Materials and Methods: The isolate UCN96 was recovered from an osteoradionecrosis wound, and was identified using the matr...

Studies support the beneficial effects of glucocorticoids (GCs) during septic shock, steering research toward the potential role of GC‐induced proteins in controlling excessive inflammatory responses. GILZ is a glucocorticoid‐induced protein involved in the anti‐inflammatory effects of GCs. We investigated whether the overexpression of GILZ specifi...

Objectives: Routine amoxicillin for children with uncomplicated severe acute malnutrition raises concerns of increasing antibiotic resistance. We performed an ancillary study nested within a double-blind, placebo-controlled trial in Niger testing the role of routine 7 day amoxicillin therapy in nutritional recovery of children 6 to 59 months of ag...

Introduction Lors de la nécrolyse épidermique (NE), la destruction épithéliale favorise la colonisation par des bactéries pathogènes opportunistes (BPO) et des infections possiblement à point de départ cutané (bactériémies à S. aureus et à P. aeruginosa). Nous avons étudié l’évolution du microbiote cutané entre les phases de décollement et de ré-ép...

Introduction Les fasciites nécrosantes (FN) sont des infections de la peau et des tissus mous mettant en jeu le pronostic vital. De rares cas secondaires à des gestes chirurgicaux ou des injections à visée esthétique ont été décrits. Observation Une patiente de 40 ans et son mari s’injectaient dans l’abdomen un produit à base d’hormone de croissan...

Introduction Les streptocoques béta-hémolytiques (SBH) représentent 30 à 40 % des bactéries responsables de dermohypodermites bactériennes nécrosantes – fasciites nécrosantes (DHBN-FN). Il s’agit principalement de Streptococcus pyogenes, SBH du groupe A (SGA) mais aussi de Streptococcus agalactiae, SBH du groupe B (SGB) et de Streptococcus dysgalac...

Background: Necrotising soft-tissue infections (NSTIs) are life-threatening, requiring broad-spectrum antibiotics. Their etiological diagnosis can be limited by poor performance of cultures and administration of antibiotics before surgery. Objectives: We aimed to: (i) compare 16S-targeted metagenomics (TM) and unbiased semi-quantitative pan-micr...

Background: Antibiotic-impregnated external ventricular drains (AI-EVDs) have a debated efficacy in clinical studies. Objectives: Our aim was to assess the durability of antimicrobial activity of AI-EVDs used in clinical settings. Methods: From April 2017 to January 2018, all consecutive AI-EVDs (Bactiseal™) inserted in adult patients were pro...

Upper tract urinary tract infections that require hospitalization have been the focus of national recommendations in 2018 by the French society of infectious diseases (Spilf). We here propose to discuss several complex-challenging situations: severe infection with sepsis, pyelonephritis in the pregnant woman, management of infections involving mult...

Background: Epidermal necrolysis (EN) involving ≥10% of the body surface area (BSA) is often complicated by bacterial infections. Objective: We sought to describe the epidemiology of bloodstream infections (BSIs) in EN involving a BSA ≥10% and the diagnostic performances of skin cultures for predicting the pathogen(s) isolated from BSIs. Method...

Introduction Les dermo-hypodermites bactériennes nécrosantes-fasciites nécrosantes (DHBN-FN) sont des infections rapidement progressives du derme et de l’hypoderme, pouvant atteindre le muscle. Nous rapportons le cas d’une DHBN-FN à streptocoque bêta-hémolytique du groupe B (SGB) sans porte d’entrée cutanée évidente, associée à un portage oropharyn...

Introduction Les infections bactériennes compliquent fréquemment les nécrolyses épidermiques (NE) avec surface décollée-décollable (SDD) ≥ 10 % (syndromes de Lyell et de chevauchement). Les objectifs de cette étude étaient de rapporter la prévalence et l’écologie des bactériémies au cours de la NE et de confirmer l’intérêt prédictif des cartes bact...

Introduction: Aspergillus fumigatus (Af) and Stenotrophomonas maltophilia (Sm) are pathogenic microorganisms, which coexist in the respiratory tract of cystic fibrosis (CF) patients. We recently developed an in vitro model of mixed biofilm associating Af ATCC 13073-GFP (Af13073) and Sm ATCC 13637 (Sm13637) and described an antibiosis effect. The pr...

The on-going pandemic of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBLE) is responsible for a global rise in carbapenem consumption that may hasten the dissemination of carbapenemase-producing Enterobacteriaceae (CPE). Hence, carbapenem sparing through the use of alternative beta-lactams is increasingly considered as potential...

Background A high level of antibiotic consumption in France means antimicrobial resistance requires rigorous monitoring. The Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) is a global surveillance study that monitors the in vitro activities of tigecycline and a panel of marketed antimicrobials against clinically important Gram-positive an...

Objectives: The Enterobacter cloacae complex (Ecc), routinely referred to as "E. cloacae" in clinical microbiology, encompasses several species with 12 genetic clusters and one sequence crowd that can be identified based on hsp60 sequencing. Little is known about the pathogenicity and distribution of resistance to antibiotics among the Ecc. Metho...

Objectives: Incidence of Extended Spectrum β-Lactamase-producing Gram Negative Bacilli (ESBL-P-GNB)-related infections is worryingly increasing worldwide. ESBL-P-GNB detection directly on bronchial aspirate samples (BAS) performed for suspected pneumonia may help save empirical carbapenems. Our objectives were to optimize β-LACTA(®) test (BLT) rea...

Purpose: Since their emergence at the beginning of the century, OXA-48 carbapenemases have spread in the community and in hospitals. To assess the diversity of OXA-48-producing bacterial strains and plasmids in the hospital setting, we studied the strains isolated from patients in three hospitals in the Paris area. Materials and methods: All pos...

Background: Antibiotic resistance is a rapidly increasing global emergency that calls for action from all of society. Intestinal multidrugresistant (MDR) bacteria have spread worldwide with extended-spectrum beta-lactamase (ESBL) -producing Enterobacteriaceae (ESBL-PE) as the most prevalent type. The millions of travelers annually visiting regions...

Eggerthella lenta is increasingly found in patients with severe comorbidities. Because oncologic patients are exposed to emerging pathogens, we aimed to describe the factors associated with E. lenta bacteremia in this immunosuppressed population. Oncology patients with blood cultures positive for E. lenta were retrospectively recorded from 2009 to...

The intestinal microbiota plays a key role in the pathogenesis of acute graft-versus-host disease (aGVHD). High-dose conditioning regimens given prior to allogeneic hematopoietic stem cell transplantation (aHSCT) modulate the composition of gut microbiota and damage the gut epithelial barrier, resulting in increased systemic inflammation. We assess...

Scopulariopsis brevicaulis onychomycosis with local cutaneous invasion was diagnosed in an acute leukemia patient and unsuccessfully treated with high-dose micafungin, based on antifungal susceptibility testing. This case should alert clinicians to the possible severe evolution of onychomycosis in neutropenic patients and suggests that surgery shou...

Introduction: During the last decade, the prevalence of the intestinal carriage of extended spectrum beta-lactamases - producing Escherichia coli (ESBL-E. coli) has continued to increase worldwide in the community, especially in developing countries. Hence, we undertook a study to determine the ESBL-E. coli fecal carriage rate and the associated r...