[Impact of the first year of the COVID-19 pandemic on the epidemiology of invasive infections (bacteremia) in the hospitals of the Assistance Publique-Hôpitaux de Paris]. / Impact de la première année de la pandémie de COVID-19 sur l'épidémiologie des infections invasives (bactériémies) dans les hôpitaux de l'Assistance Publique­Hôpitaux de Paris.

Introduction: The COVID-19 pandemic has led to a massive influx of patients suffering from severe forms of the disease into hospitals, often requiring intensive care (vascular catheters, ventilation, etc.) which exposes them to high risks of nosocomial infections, particularly invasive infections (bacteremia). Method: The impact of the COVID-19 pandemic on the epidemiology of bacteremia in 2020 was analysed in 25 hospitals of the Assistance Publique-Hôpitaux de Paris (AP-HP, approximately 14,000 beds, covering the Île-de-France region). Up to a quarter of patients admitted to AP-HP during the March-April period (peak of the 1st wave) were infected with COVID-19. The incidence over 100 admissions of bacteraemia increased overall compared to previous years: by 24% in March 2020 and by 115% in April. Results: The evolution of the incidence of bacteremia was not the same for 2 groups of microorganisms with very different ecologies. For the "hospital" type microorganisms classically responsible for nosocomial infections, the incidence increased significantly in March-April 2020: Klebsiella pneumoniae (×2.3), Pseudomonas aeruginosa (×2.4), Staphylococcus aureus (×2.4), enterococci (×3.4), yeasts (×2.7). Two thirds of the bacteremias caused by these microorganisms were considered as acquired during hospitalization. Importantly, there was also a sharp increase in the incidence of bacteremia caused by antibiotic-resistant strains. The antibiotics used as indicators were the 3rd generation cephalosporins (3GCs), major antibiotics in the treatment of serious infections used for monitoring bacterial resistance in Europe. For example, the incidence of bacteremia with 3GC-resistant strains increased threefold in April 2020 for K. pneumoniae. During the same period, the consumption of 3GC increased sharply in the same hospitals (+131% in March and +148% in April). For Streptococcus pneumoniae (pneumococcus) and Streptococcus pyogenes (group A hemolytic streptococcus), two pathogens responsible for mainly community and respiratory-transmitted infections, the pandemic had the opposite effect. There was a decrease in incidence in 2020 by 34% and 28% respectively for these two species, particularly in the spring when strict containment, physical distancing and mask-wearing measures were in place. A slight re-emergence of infections with these two species occurred in the summer of 2020 after the relaxation of prevention measures. In contrast to what was seen above, 4/5 of the bacteremias caused by these two species were considered as community-acquired. Conclusion: The COVID-19 pandemic which had a strong impact on hospital management and social organization in the general population, had opposite impacts on the incidence of bacteremia depending on the pathogens and their mode of transmission.

Impact of 24/7 loading of blood culture bottles in a new automated incubator on the diagnosis of bloodstream infections.

Blood culturing (BC) remains the gold standard for bloodstream diagnosis but its workflow is slow. We aimed reducing this time by implementing a new automated incubator with a 24/7 BC workflow. With this new strategy, time to incubation was shorter (1.52 h vs 6.82 h), positivity rates were higher (10.6% vs 8.9%, p<0.05), and the number of BSI diagnostics increased (16.1% vs 13.8% patients and 2.3 vs 1.9 density episode per 1000 hospital days). Our results show that implementing automatic loading of BC bottles with a 24/7 strategy not only shortened time to diagnosis but significantly increased the BSI diagnosis rate.

Monitoring antimicrobial resistance (AMR) using CUSUM control charts.

We evaluated the use of the Cumulative Summation (CUSUM) control chart methodology for detection of an excessive increase in antimicrobial-resistant (AMR) bacteria acquisition. We used administrative, clinical and bacteriological data from all 157,570 patients hospitalized for at least 48 h from January 1, 2010 to December 31, 2015 in a 654-bed university teaching hospital in Paris, France. Monthly computed CUSUM were evaluated for the detection of out-of-control situations, defined as incidence rates of acquired AMR bacterial colonization exceeding acceptable thresholds at the hospital and ward levels (based on six selected wards) for AMR bacteria overall and Extended-spectrum beta-lactamases Enterobacteriaceae (ESBL-E) and Methicillin-resistant Staphylococcus aureus (MRSA), specifically. During the study period, 1,403 samples of acquired AMR bacteria were identified including 1,129 ESBL-E and 151 MRSA. The incidence rate of acquired AMR bacteria was stable at the hospital and the wards level. When based on AMR bacteria overall, CUSUM alarms were triggered at the hospital level and at the ward level in four units. For ESBL-E, CUSUM tests generated alarms at the hospital level and for the same four wards, and for MRSA, CUSUM tests detected out-of-control situations in all the wards. The CUSUM approach appears complementary with hospital infection control strategies currently in practice and appears of interest in common practice as a simple tool for AMR surveillance.

Assessment of coinfection of sexually transmitted pathogen microbes by use of the anyplex II STI-7 molecular kit.

Anyplex STI-7 is a new molecular kit that detects seven sexually transmitted pathogens. Among 202 subjects screened for genital infection, 143 (70.4%) were diagnosed with at least one pathogen, in concordance with reference methods. In addition, the Anyplex STI-7 demonstrated coinfections, such as that with Ureaplasma parvum and Chlamydia trachomatis, in young women.

Novel scores relevant to antimicrobial resistance and hospital-acquired infections developed with data from a multi-hospital consortium in the Parisian region of France.

PURPOSE: Indicators for comparing and understanding differences in antimicrobial resistance (AMR) and healthcare-associated infections (HAIs) for benchmarking are essential to identify priorities for hospitals. METHODS: This study measured the incidence of hospital-acquired or resistant Gram-negative bacilli bloodstream infections (GNB-BSIs) in a large public healthcare consortium in the Parisian region of France. RESULTS: Within each hospital, there was a strong positive correlation between the incidence of GNB-BSIs due to resistant GNB and the incidence of hospital-acquired GNB-BSIs. Two scores measuring AMR and HAI rates by combining different GNB-BSI incidence rates were developed as indicators. These scores were highly variable within the hospital consortium. On multi-variate analysis, AMR and HAI scores were significantly associated with the proportion of surgical beds, staff absenteeism and the consumption of alcohol-based hand rub, with the latter two characteristics being amenable to interventions. Carbapenem use was also linked to AMR, but this may be because carbapenems are the preferred drug for treating resistant infections. CONCLUSION: These results shed light on the incidence of HAIs and AMR in the study hospitals, and suggest possibilities for targeted interventions at healthcare facility level.

The impact of crown-rump length measurement error on combined Down syndrome screening: a simulation study.

OBJECTIVE: To evaluate the impact of a 5-mm error in the measurement of crown-rump length (CRL) in a woman undergoing ultrasound and biochemistry sequential combined screening for Down syndrome. METHODS: Based on existing risk calculation algorithms, we simulated the case of a 35-year-old-woman undergoing combined screening based on nuchal translucency (NT) measurement and early second-trimester maternal serum markers (human chorionic gonadotropin (hCG) and alpha-fetoprotein (AFP) expressed as multiples of the median (MoM)). Two measurement errors were considered (+ or - 5 mm), for four different CRLs (50, 60, 70 and 80 mm), with five different NT measurements (1, 1.5, 2, 2.5 and 3 mm) in a patient undergoing biochemistry testing at 14 + 4, 15, 16, 17 or 18 weeks' gestation. Four different values for each maternal serum marker were tested (1, 1.5, 2 and 2.5 MoM for hCG, and 0.5, 0.8, 1 and 1.5 MoM for AFP), leading to a total of 3200 simulations of the impact of measurement error. In all cases the ratio between the risk as assessed with or without the measurement error was calculated (measurement error-related risk ratio (MERR)). RESULTS: Over 3200 simulated cases, MERR ranged from 0.53 to 2.14. In 586 simulations (18.3%), it was < 0.66 or > 1.33. Based on a risk cut-off of 1/300, women would have been misclassified in 112 simulations (3.5%). This would go up to 33 (27.5%) out of the 120 simulations in women with 'borderline' risk, with 1.5 MoM for hCG and 0.5 MoM for AFP, and NT measurement of 1 or 2mm. CONCLUSION: Down syndrome screening may be highly sensitive to measurement errors in CRL. Quality control of CRL measurement should be performed together with quality control of NT measurement in order to provide the highest standard of care.

Determination of Escherichia coli phylogroups in elderly patients with urinary tract infection or asymptomatic bacteriuria.

OBJECTIVES: Distinguishing between urinary tract infection (UTI) and asymptomatic bacteriuria (ABU) is difficult in the geriatric population since specific symptoms are often lacking. Escherichia coli is the most frequent UTI pathogen in this population but also a common urine colonizer. We hypothesized that detecting E. coli phylogroups B2 or D, which were previously associated with virulent strains responsible for extra-intestinal infections outside elderly patients, could help in distinguishing UTI from ABU. METHODS: Consecutive cases of E. coli bacteriuria diagnosed in hospitalized patients >75 years old during 3 months were investigated for E. coli phylogroups. Multiplex PCR was used to search for several virulence genes as previously described. Characteristics of UTI and ABU cases, assessed retrospectively according to definitions and geriatric expertise, were compared. RESULTS: Out of 233 bacteriuria cases, 60 were assessed to be UTI and 163 to be ABU, with 10 cases unclassified. E. coli strains belonging to the phylogroups B2 and D were significantly more frequent in UTI (48/60, 80%) than in ABU (101/163, 62%) by univariate and multivariate analyses (OR 3.05, 1.44-6.86, p 0.005). Out of all the host and bacterial characteristics studied, falls (p 0.032), comorbidities (p 0.041), and altered autonomy evaluated by a low activity of daily living score (p 0.027) were also associated with UTI using univariate and multivariate analysis. CONCLUSIONS: Determination of the E. coli phylogroup, in addition to some host characteristics, can help to distinguish UTI from ABU in elderly patients with bacteriuria. If this hypothesis is confirmed by prospective studies, then inappropriate use of antibiotics may be reduced in ABU cases.