Decisive Role of Polymer-Bovine Serum Albumin Interactions in Biofilm Substrates on ``Philicity'' and Extracellular Polymeric Substances Composition

Formation of extracellular polymeric substances (EPS) is a crucial step for bacterial biofilm growth. The dependence of EPS composition on growth substrate and conditioning of the latter is thus of primary importance. We present results of studies on the growth of biofilms of two different strains each, of the Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae, on four polymers used commonly in indwelling medical devices-polyethene, polypropylene, polycarbonate, and polytetrafluoroethylene-immersed in bovine serum albumin (BSA) for 24 h. The polymer substrates are studied before and after immersing in BSA for 9 and 24 h, using contact angle measurement (CAM) and field emission scanning electron microscopy (FE-SEM) to extract, respectively, the ``philicity'' phi (defined as -cos theta, where theta is the contact angle of the liquid on the solid at a particular temperature and ambient pressure) and spatial Hirsch parameter H (defined from the relation F(r) similar to r(2H), where F(r) is the mean squared density fluctuation at the sample surface). H = 0.5, 0.5 signifies no correlation, anticorrelation, and correlation, respectively. The substrates are seen to transform from large hydrophobicity to near amphiphilicity with the formation of a BSA conditioning surface layer, and the H-values distinguish the length scales of 100, 500, and 2000 nm, with the anticorrelation increasing with length scale. Biofilms of E. coli did not grow on bare PTFE and HDPE substrates. Biofilms grown on BSA-covered surfaces are studied with CAM, FE-SEM, Fourier transform infrared (FTIR), and surface-enhanced Raman spectroscopy (SERS). Both spectra and f-values were independent of bacterial species but dependent on the polymer, while H-values show some bacterial variation. Thus, EPS composition and wetting properties of the corresponding bacterial biofilms seem to be decided by the interaction of the conditioning BSA layer with the specific polymer substrate

Infection in cirrhosis: A prospective study

Introduction and objectives: Multidrug-resistant (MDR) infections in cirrhosis are associated with poor outcomes. We attempted a prospective study on infections in patients with cirrhosis evaluating microbiology of these infections and how outcomes depended on factors like bacterial resistance, appropriate antibiotics, stage of liver disease and whether outcomes were significantly different from patients who did not have infections. Materials and methods: This was a prospective evaluation involving one hundred and fifty nine patients with cirrhosis who were admitted at Peerless Hospitex Hospital and Research Center, Kolkata, West Bengal, India, during a 24 month period. One hundred and nineteen of these patients either had an infection at the time of admission or developed infection during hospitalization. Forty patients did not have an infection at admission and did not acquire infection while admitted. Data was collected about demographics, etiology of cirrhosis, liver and renal function and microbiology. Results: Infections were community acquired in 27.7% of patients, healthcare associated in 52.9% and nosocomial in 19.3%. Gram negative bacilli (Escherichia coli 47.4% Klebsiella pneumoniae 23%) were common. 84.9% of enterobacteriaceae produced ESBL, AmpC or Carbapenemases. Spontaneous bacteria peritonitis (SBP) and urinary tract infection (UTI) were the most common sites of infection. In hospital mortality was 21.9%. Non-survivors had higher MELD (26 vs 19, p < 0.001) and CTP scores (11.7 vs 10.3, p < 0.001). The control group had lower MELD (16.65 vs. 20.8, p < 0.001) and CTP scores (9.25 vs 10.59, p < 0.001). Conclusions: MDR infections are common in patients with cirrhosis and have serious implications for treatment and outcomes

The impact of COVID-19 on health care–associated infections in intensive care units in low- and middle-income countries: International Nosocomial Infection Control Consortium (INICC) findings

•Due to the COVID pandemic, health care–associated infection rates increased in resource-limited countries.•Due to the COVID pandemic, rates of central line–associated bloodstream infections increased.•Due to the COVID pandemic, rates of central ventilator–associated events increased.•Due to the COVID pandemic, mortality rates increased in intensive care units of resource-limited countries in 2020.•Due to the COVID pandemic, average length of stay increased in resource-limited countries in 2020. This study examines the impact of the COVID-19 pandemic on health care–associated infection (HAI) incidence in low- and middle-income countries (LMICs). Patients from 7 LMICs were followed up during hospital intensive care unit (ICU) stays from January 2019 to May 2020. HAI rates were calculated using the International Nosocomial Infection Control Consortium (INICC) Surveillance Online System applying the Centers for Disease Control and Prevention's National Healthcare Safety Network (CDC-NHSN) criteria. Pre–COVID-19 rates for 2019 were compared with COVID-19 era rates for 2020 for central line–associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), ventilator-associated events (VAEs), mortality, and length of stay (LOS). A total of 7,775 patients were followed up for 49,506 bed days. The 2019 to 2020 rate comparisons were 2.54 and 4.73 CLABSIs per 1,000 central line days (risk ratio [RR] = 1.85, p = .0006), 9.71 and 12.58 VAEs per 1,000 mechanical ventilator days (RR = 1.29, p = .10), and 1.64 and 1.43 CAUTIs per 1,000 urinary catheter days (RR = 1.14; p = .69). Mortality rates were 15.2% and 23.2% for 2019 and 2020 (RR = 1.42; p < .0001), respectively. Mean LOS for 2019 and 2020 were 6.02 and 7.54 days (RR = 1.21, p < .0001), respectively. This study documents an increase in HAI rates in 7 LMICs during the first 5 months of the COVID-19 pandemic and highlights the need to reprioritize and return to conventional infection prevention practices

Six-year multicenter study on short-term peripheral venous catheters-related bloodstream infection rates in 727 intensive care units of 268 hospitals in 141 cities of 42 countries of Africa, the Americas, Eastern Mediterranean, Europe, South East Asia, and Western Pacific Regions: International Nosocomial Infection Control Consortium (INICC) findings

Short-term peripheral venous catheter-related bloodstream infection (PVCR-BSI) rates have not been systematically studied in resource-limited countries, and data on their incidence by number of device days are not available. Prospective, surveillance study on PVCR-BSI conducted from September 1, 2013, to May 31, 2019, in 727 intensive care units (ICUs), by members of the International Nosocomial Infection Control Consortium (INICC), from 268 hospitals in 141 cities of 42 countries of Africa, the Americas, Eastern Mediterranean, Europe, South East Asia, and Western Pacific regions. For this research, we applied definition and criteria of the CDC NHSN, methodology of the INICC, and software named INICC Surveillance Online System. We followed 149,609 ICU patients for 731,135 bed days and 743,508 short-term peripheral venous catheter (PVC) days. We identified 1,789 PVCR-BSIs for an overall rate of 2.41 per 1,000 PVC days. Mortality in patients with PVC but without PVCR-BSI was 6.67%, and mortality was 18% in patients with PVC and PVCR-BSI. The length of stay of patients with PVC but without PVCR-BSI was 4.83 days, and the length of stay was 9.85 days in patients with PVC and PVCR-BSI. Among these infections, the microorganism profile showed 58% gram-negative bacteria: Escherichia coli (16%), Klebsiella spp (11%), Pseudomonas aeruginosa (6%), Enterobacter spp (4%), and others (20%) including Serratia marcescens. Staphylococcus aureus were the predominant gram-positive bacteria (12%). PVCR-BSI rates in INICC ICUs were much higher than rates published from industrialized countries. Infection prevention programs must be implemented to reduce the incidence of PVCR-BSIs in resource-limited countries

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific. During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied. Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher. Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively

Six-year multicenter study on short-term peripheral venous catheters-related bloodstream infection rates in 204 intensive care units of 57 hospitals in 19 cities of India: International Nosocomial Infection Control Consortium (INICC) findings

•We report peripheral venous catheters (PVC)-related BSI rates from 2013 to 2019.•We collected prospective data from 204 ICUs in 57 hospitals in 19 cities of India.•We followed 7,513 ICU patients for 296,893 bed-days and 295,795 PVC-days.•We identified 863 PVC-related BSIs, amounting to a rate of 2.91/1,000 PVC-days. Short-term peripheral venous catheters-related bloodstream infections (PVCR-BSIs) rates have not been systematically studied in developing countries, and data on their incidence by number of device-days are not available. Prospective, surveillance study on PVCR-BSI conducted from September 1, 2013 to May 31, 2019 in 204 intensive care units (ICUs), members of the International Nosocomial Infection Control Consortium (INICC), from 57 hospitals in 19 cities of India. We applied US INICC definition criteria and reported methods using the INICC Surveillance Online System. We followed 7,513 ICU patients for 296,893 bed-days and 295,795 short term peripheral venous catheter (PVC)-days. We identified 863 PVCR-BSIs, amounting to a rate of 2.91/1,000 PVC-days. Mortality in patients with PVC but without PVCR-BSI was 4.14%, and 11.59% in patients with PVCR-BSI. The length of stay in patients with PVC but without PVCR-BSI was 4.13 days, and 5.9 days in patients with PVCR-BSI. The micro-organism profile showed 68% of gram negative bacteria: Escherichia coli (23%), Klebsiella spp (15%), Pseudomonas aeruginosa (5%), and others. The predominant gram-positive bacteria were Staphylococcus aureus (10%). PVCR-BSI rates found in our ICUs were much higher than rates published from industrialized countries. Infection prevention programs must be implemented to reduce the incidence of PVCR-BSIs

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2013-2018, Adult and Pediatric Units, Device-associated Module

•Data from 428,847 patients, 2,815,402 bed-days.•We collected 1,468,216 line days, 1,053,330 ventilator days, 1,740,776 urinary catheter days.•We found 7,785 CLAB, 12,085 VAE, and 5,509 CAUTI.•HAI rates were 5.91% and 9.01 HAIs/1,000 bed-days.•CLAB rate was 5.3/1000 CL-days; VAE rate was 11.4/1000 MV-days, CAUTI rate was 3.1/1000 UC-days. We report the results of INICC surveillance study from 2013 to 2018, in 664 intensive care units (ICUs) in 133 cities, of 45 countries, from Latin-America, Europe, Africa, Eastern-Mediterranean, Southeast-Asia, and Western-Pacific. Prospective data from patients hospitalized in ICUs were collected through INICC Surveillance Online System. CDC-NHSN definitions for device-associated healthcare-associated infection (DA-HAI) were applied. We collected data from 428,847 patients, for an aggregate of 2,815,402 bed-days, 1,468,216 central line (CL)-days, 1,053,330 mechanical ventilator (MV)-days, 1,740,776 urinary catheter (UC)-days. We found 7,785 CL-associated bloodstream infections (CLAB), 12,085 ventilator-associated events (VAE), and 5,509 UC-associated urinary tract infections (CAUTI). Pooled DA-HAI rates were 5.91% and 9.01 DA-HAIs/1,000 bed-days. Pooled CLAB rate was 5.30/1,000 CL-days; VAE rate was 11.47/1,000 MV-days, and CAUTI rate was 3.16/1,000 UC-days. P aeruginosa was non-susceptible (NS) to imipenem in 52.72% of cases; to colistin in 10.38%; to ceftazidime in 50%; to ciprofloxacin in 40.28%; and to amikacin in 34.05%. Klebsiella spp was NS to imipenem in 49.16%; to ceftazidime in 78.01%; to ciprofloxacin in 66.26%; and to amikacin in 42.45%. coagulase-negative Staphylococci and S aureus were NS to oxacillin in 91.44% and 56.03%, respectively. Enterococcus spp was NS to vancomycin in 42.31% of the cases. DA-HAI rates and bacterial resistance are high and continuous efforts are needed to reduce them

Six-year study on peripheral venous catheter-associated BSI rates in 262 ICUs in eight countries of South-East Asia: International Nosocomial Infection Control Consortium findings

Short-term peripheral venous catheter-associated bloodstream infection rates have not been systematically studied in Asian countries, and data on peripheral venous catheter-associated bloodstream infections incidence by number of short-term peripheral venous catheter days are not available. Prospective, surveillance study on peripheral venous catheter-associated bloodstream infections conducted from 1 September 2013 to 31 May 2019 in 262 intensive care units, members of the International Nosocomial Infection Control Consortium, from 78 hospitals in 32 cities of 8 countries in the South-East Asia Region: China, India, Malaysia, Mongolia, Nepal, Philippines, Thailand, and Vietnam. For this research, we applied definition and criteria of the CDC NHSN, methodology of the INICC, and software named INICC Surveillance Online System. We followed 83,295 intensive care unit patients for 369,371 bed-days and 376,492 peripheral venous catheter-days. We identified 999 peripheral venous catheter-associated bloodstream infections, amounting to a rate of 2.65/1000 peripheral venous catheter-days. Mortality in patients with peripheral venous catheter but without peripheral venous catheter-associated bloodstream infections was 4.53% and 12.21% in patients with peripheral venous catheter-associated bloodstream infections. The mean length of stay in patients with peripheral venous catheter but without peripheral venous catheter-associated bloodstream infections was 4.40 days and 7.11 days in patients with peripheral venous catheter and peripheral venous catheter-associated bloodstream infections. The microorganism profile showed 67.1% were Gram-negative bacteria: (22.9%), spp (10.7%), (5.3%), spp. (4.5%), and others (23.7%). The predominant Gram-positive bacteria were (11.4%). Infection prevention programs must be implemented to reduce the incidence of peripheral venous catheter-associated bloodstream infections