Background Bloodstream infections (BSIs) are an emerging cause of significant morbidity and mortality in severe Coronavirus disease 2019 (COVID-19). We aimed to assess the prevalence, clinical profile and outcome of BSIs in critically ill COVID-19 patients. Methods This was a single-centre retrospective study conducted at a tertiary care hospital in Western India. All patients (age > 18 years) with reverse-transcription polymerase chain reaction (RT-PCR) confirmed COVID-19 admitted in the intensive care unit (ICU) were included. Hospital electronic records were searched for demographic data, time of bloodstream infection since admission, clinical profile, antimicrobial resistance pattern and clinical outcome of all patients who developed BSIs. Results Out of 750 patients admitted in COVID ICU, 8.5% developed secondary BSIs. All severe COVID-19 patients who developed BSIs succumbed to illness. A significant proportion of BSIs were Gram-negative pathogens (53/64, 82.8%). Acinetobacter baumannii was the commonest isolate, followed by Klebsiella pneumoniae (32.8% and 21.9%, respectively). Multidrug-resistance organisms (MDRO) were found in 57.8% of the cases. The majority of MDRO belonged to K. pneumoniae and Enterococcus groups. The proportion of Gram-negative bacteria resistant to carbapenems was 47.2% (25/53). On multivariate analysis, raised total leukocyte counts, mechanical ventilation and presence of comorbidities were significantly associated with the incidence of BSIs. Conclusion We found a significant prevalence of Acinetobacter baumannii in COVID-19 associated BSIs. The presence of comorbidities raised leukocyte counts and mechanical ventilation should alarm clinicians for possible BSIs. The timely initiation of empirical antibiotics and rapid de-escalation is vital to improve the outcome. At the same time, strict compliance of infection control practices should be accomplished to reduce the occurrence of MDRO.

AmpC β-lactamases are clinically important cephalosporinases encoded on the chromosomes of many Enterobacteriaceae and a few other organisms, where they mediate resistance to cephalothin, cefazolin, cefoxitin, most penicillins, and β-lactamase inhibitor/β-lactam combinations. The increase in antibiotic resistance among Gram-negative bacteria is a notable example of how bacteria can procure, maintain and express new genetic information that can confer resistance to one or several antibiotics. Detection of organisms producing these enzymes can be difficult, because their presence does not always produce a resistant phenotype on conventional disc diffusion or automated susceptibility testing methods. These enzymes are often associated with potentially fatal laboratory reports of false susceptibility to β-lactams phenotypically. With the world-wide increase in the occurrence, types and rate of dissemination of these enzymes, their early detection is critical. AmpC β-lactamases show tremendous variation in geographic distribution. Thus, their accurate detection and characterization are important from epidemiological, clinical, laboratory, and infection control point of view. This document describes the methods for detection for AmpC β-lactamases, which can be adopted by routine diagnostic laboratories.

The greatest threat to antimicrobial treatment of infections caused by Gram-negative bacteria is the production of carbapenemases. Metallo-beta-lactamases and plasmid-mediated serine carbepenemases like Klebsiella pneumonia carbapenemase are threatening the utility of almost all currently available beta-lactams including carbapenems. Detection of organisms producing carbapenemases can be difficult, because their presence does not always produce a resistant phenotype on conventional disc diffusion or automated susceptibility testing methods. These enzymes are often associated with laboratory reports of false susceptibility to carbapenems which can be potentially fatal. Moreover, most laboratories do not attempt to detect carbapenemases. This may be due to the lack of availability of guidelines and procedures or lack of knowledge and expertise. Because routine susceptibility tests may be unreliable, special tests are required to detect the resistance mechanisms involved. This document describes the standard methodology for detection of various types of carbapenemases, which can be put to use by laboratories working on antimicrobial resistance in Gram-negative bacteria.

Purpose:Bloodstream infections (BSIs) are one of the major life-threatening infections in hospitals. They are responsible for prolonged hospital stays, high healthcare costs, and significant mortality. The epidemiology of BSIs varies between hospitals necessitating analysis of local trends. Few studies are available on trauma patients, who are predisposed due to the presence of multiple invasive devices.Materials and Methods:A prospective surveillance of all BSIs was done at a level 1 trauma center from April, 2011 to March, 2012. All patients admitted to the different trauma intensive care units (ICUs) were monitored daily by attending physicians for subsequent development of nosocomial BSI. An episode of BSI was identified when patients presented with one or more of the following signs/symptoms, that is, fever, hypothermia, chills, or hypotension and at least one or more blood culture samples demonstrated growth of pathogenic bacteria. BSIs were further divided into primary and secondary BSIs as per the definitions of Center for Disease Control and Prevention. All patients developing nosocomial BSIs were followed till their final outcome.Results:A total of 296 episodes of nosocomial BSIs were observed in 240 patients. A source of BSI was identified in 155 (52%) episodes. Ventilator-associated pneumonia was the most common source of secondary BSI. The most common organism was Acinetobacter sp. (21.5%). Candida sp. accounted for 12% of all blood stream organisms. A high prevalence of antimicrobial resistance was observed in Gram-negative and-positive pathogens.Conclusions:Trauma patients had a high prevalence of BSIs. Since secondary bacteremia was more common, a targeted approach to prevention of individual infections would help in reducing the burden of BSIs.