Distribution and drug resistance analysis of pathogenic bacteria in a hospital blood culture, 2018-2022

Objective: To analyze the distribution and drug resistance of pathogenic bacteria in blood culture specimens of patients with bloodstream infections before and after COVID-19 (2018-2019 and 2020-2021), and to provide scientific basis and reference for rational treatment and effective control of bloodstream infections in the post-epidemic period. Methods: Blood culture specimens were collected from patients in Zhongnan Hospital of Wuhan University in the two years before and after the COVID-19 outbreak (2018-2021). The Automated Blood Culture Systems were used to perform blood culture on blood specimens sent for clinical inspection, and the Vitek MS automatic bacterial identification mass spectrometer was used for strain identification and the Vitek 2 automatic bacterial drug susceptibility analyzer was used for drug susceptibility testing and drug resistance analysis. Results: Blood culture specimens were performed on 28 736 patients with suspected bloodstream infection submitted for inspection from January 2018 to December 2019, and a total of 2 181 strains of pathogenic bacteria were detected after removing duplicate strains, with a positive rate of 7.69%, including 1 046 strains of Gram-negative bacteria, accounting for 47.96%. From January 2020 to December 2021, blood culture specimens from 26 083 patients with suspected bloodstream infection were submitted for inspection, and a total of 2 111 strains of pathogenic bacteria were detected after excluding duplicate strains, with a positive rate of 8.09%, including 1 000 strains of Gram-negative bacteria accounted for 47.37%. The drug resistance of Klebsiella pneumoniae was relatively serious, and the sensitivity rate to ertapenem, polymyxin B and tigecycline was more than 90%. The main non-fermentative bacteria Acinetobacter baumannii was more than 50% sensitive to piperacillin/tazobactam, amikacin and polymyxin B. The sensitivity rates of Pseudomonas aeruginosa to piperacillin/tazobactam, ceftazidime, cefepime, amikacin, gentamicin, tobramycin, ciprofloxacin, levofloxacin, piperacillin and meropenem were more than 50%. Conclusions: In the two years before and after COVID-19, there are many types of pathogenic bacteria in bloodstream infection, but the distribution do not differ significantly. The pathogens of bloodstream infection are mainly distributed in ICU, hepatobiliary research institute, and nephrology department. Among them, Gram-negative bacteria such as Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii are the main ones, and different pathogens showed great differences in drug resistance.

Effect of bloodstream infection on survival in COVID-19 patients admitted to an intensive care unit in Colombia: a matched cohort analysis.

Aim: To determine the impact of bloodstream infection (BSI) and other risk factors for mortality in patients with COVID-19 admitted to the intensive care unit (ICU). Methods: A retrospective cohort was carried out at the Hospital Universitario Nacional (HUN) between March 29 and December 19, 2020. Patients with COVID-19 admitted to the Intensive Care Unit (ICU) were paired 1:4 in two groups, one with BSI and the other without, according to hospital stay and the month of admission. The primary outcome was mortality at 28 days. A Cox proportional hazards model was used to estimate differences in mortality risk. Results: 456 patients were identified and 320 were included in the final cohort, 18% (n = 59) in the BSI group and 82% (n = 261) in the control group. 125 (39%) patients died, 30 (51%) in the BSI group and 95 (36%) in the control group (P = 0.040). BSI was associated with an increased risk of in-hospital mortality at 28 days, [HR] 1.77 (95% CI: 1.03-3.02; P = 0.037). Invasive mechanical ventilation (IMV) and age were associated with increased mortality risk. Some months of the year of the hospital stay were associated with a reduced risk of mortality. There was no difference in mortality between inappropriate and appropriate empirical antimicrobial use. Conclusion: BSI in patients with COVID-19 in ICU increases in-hospital mortality to 28 days. Other risk factors for mortality were IMV and age.

Australian Group on Antimicrobial Resistance (AGAR) Australian Enterococcal Surveillance Outcome Program (AESOP).

Abstract: From 1 January to 31 December 2021, forty-eight institutions around Australia participated in the Australian Enterococcal Surveillance Outcome Programme (AESOP). The aim of AESOP 2021 was to determine the proportion of enterococcal bacteraemia isolates in Australia that were antimicrobial resistant, and to characterise the molecular epidemiology of the Enterococcus faecium isolates. Of the 1,297 unique episodes of enterococcal bacteraemia investigated, 94.4% were caused by either E. faecalis (54.1%) or E. faecium (40.3%). Ampicillin resistance was detected in one E. faecalis isolate and in 89.3% of E. faecium isolates. Vancomycin non-susceptibility was not detected in E. faecalis but was detected in 37.9% of E. faecium. Overall, 39.6% of E. faecium harboured the vanA and/or vanB genes. For the vanA/vanB positive E. faecium isolates, 35.8% harboured the vanA gene and 64.2% the vanB gene. Although the percentage of vancomycin-resistant E. faecium bacteraemia isolates was significantly lower than that reported in the 2020 AESOP report (presumably due to the COVID-19 elective surgery restrictions placed on hospitals), it remains substantially higher than that recorded in most European countries. Isolates of E. faecium consisted of 73 multi-locus sequence types (STs); 77.2% of isolates were classified into seven major STs each containing more than ten isolates. All major STs belonged to clonal cluster (CC) 17, a major hospital-adapted polyclonal E. faecium cluster. The major STs (ST17, ST1424, ST796, ST78, ST80, ST1421 and ST555) were found across most regions of Australia. The predominant ST was ST17 which was identified in all regions except the Northern Territory. Overall, 46.5% of isolates belonging to the seven major STs harboured the vanA or vanB gene. The AESOP 2021 has shown that enterococcal bacteraemia episodes in Australia are frequently caused by polyclonal ampicillin-resistant high-level gentamicin resistant vanA- or vanB-positive E. faecium which have limited treatment options.

Large increase in bloodstream infections with carbapenem-resistant Acinetobacter species during the first 2 years of the COVID-19 pandemic, EU/EEA, 2020 and 2021.

Recent data from the European Antimicrobial Resistance Surveillance Network (EARS-Net) show a large increase of +57% in Acinetobacter species bloodstream infections in the European Union and European Economic Area in the first years of the COVID-19 pandemic (2020-2021) compared with 2018-2019. Most were resistant to carbapenems, from intensive care units, and in countries with ≥ 50% carbapenem resistance in Acinetobacter spp. in 2018-2019. This highlights the requirement for reinforced Acinetobacter preparedness and infection prevention and control in Europe.

Quarterly epidemiological data on Clostridioides difficile infection, Escherichia coli bacteraemia, Staphylococcus aureus bacteraemia and Surgical Site Infection in Scotland April to June 2021 (Q2) 2021

Antimicrobial Resistance and Healthcare Associated Infection (ARHAI) Scotland provided a commentary on quarterly epidemiological data in Scotland for April to June (Q2) 2021 on the following: Clostridioides difficile infection, Escherichia coli bacteraemia, Staphylococcus aureus bacteraemia and surgical site Infection. Data are provided for the 14 NHS boards and one NHS Special Health board. Results showed that there were 277 CDI cases, of which 73.3% (203) were healthcare infections. In theprevious quarter there were 262 cases. There were 1103 ECB cases, of which 48.2% (532) were healthcare infections. In the previous quarter there were 961 cases. There were 408 SAB cases, of which 63.7% (260) were healthcare infections. In the previous quarter there were 388 SAB cases. Epidemiological data for SSI were not included for this quarter due to the pausing of surveillance to support the COVID-19 response. The data used for this report is part of the mandatory surveillance in Scotland. ARHAI Scotland supports NHS boards to analyse their data. Local monitoring in hospital and community settings isrequired to reduce these infections.

Antimicrobial resistance patterns of bacterial and fungal isolates in COVID-19

Background: The pattern of bacterial infection in coronavirus disease 2019 (COVID-19) patients differ worldwide. Objectives: This study aimed to determine the patterns of bacterial infections and the antibiotic resistance profile by VITEK 2 (bioMerieux, France) in the culture of blood samples from hospitalized patients with COVID-19.

Characteristics and influencing factors for Stenotrophomonas maltophilia infection in a tertiary general hospital of Sanya city and drug resistance from 2016 to 2020

OBJECTIVE: To investigate the characteristics and influencing factors for Stenotrophomonas maltophilia (SMA) infection in Sanya and analyze the drug resistance so as to provide guidance for prevention and control of infection in medical institutions. METHODS: The hospitalization data were collected from the patients with SMA infection who were hospitalized in three tertiary general hospitals of Sanya from 2016 to 2020. The characteristics of SMA infection and influencing factors for respiratory tract and non-respiratory tract SMA infection were retrospectively analyzed, and the result of drug susceptibility testing was observed. RESULTS: A total of 753 case times of patients had SMA infection, including 606 (80.48%) case times of respiratory tract infection and 147 (19.52%) case times of non-respiratory tract infection. The isolation rate was the highest in respiratory medicine department (16.73%), followed by critical care medicine department (15.67%) and neurosurgery department (12.35%). The percentages of the patients with advanced age, complications with hypertension and pulmonary diseases, tracheotomy were the higher in the respiratory tract infection group than in the non-respiratory tract infection group (P < 0.05);while the percentages of the patients with malignant tumors, bacteremia, surgery, urinary tract intubation, low immunity and use of antibiotics and immunosuppressants were the higher in the non-respiratory tract infection group than in the respiratory tract infection group (P < 0.05). The result of drug susceptibility testing showed that the drug resistance rate of the SMA strains to sulfamethoxazole-trimethoprim was only 2.39%, while the drug resistance rate to ceftazidime was as high as 74.50%. CONCLUSION: The major influencing factors for the respiratory tract SMA infection include pulmonary diseases, hypertension, advanced age and tracheotomy;the influencing factors for the non-respiratory tract SMA infection include malignant tumors, low immunity, long-term excessive use of immunosuppressants and broad-spectrum antibiotics, bacteremia, surgery and urinary tract intubation. The SMA strains isolated from the city are highly sensitive to sulfamethoxazole-trimethoprim but are highly resistant to ceftazidime and chloramphenicol. It is necessary for the hospital to reasonably use antibiotics based on the result of drug susceptibility testing.

Quarterly epidemiological data on CDI, ECB, SAB and SSI in Scotland

On 5 July 2022, quarterly epidemiological data on Clostridioides difficile infection (CDI), Escherichia coli bacteraemia (ECB), Staphylococcus aureus bacteraemia (SAB), and surgical site infection (SSI) in Scotland, covering January to March (Q1) 2022, was published under the mandatory programmes for surveillance of CDI, ECB, SAB, and SSI in Scotland. Please note, data for SSI are not included due to the pausing of surveillance to support the COVID-19 response. This report provides data for the first quarter of 2022 in 14 NHS boards and one NHS special health board. In addition, an appendix can also be accessed which details all cases and denominator data for each NHS board, and for Scotland overall.

Infectious spondylodiscitis: When a rare infection is associated with uncommon findings!

Infectious spondylodiscitis (ISD) is a rare infection of the spine. ISD caused by Acinetobacter baumannii and Citrobacter koseri is even rarer. Moreover, the association between ISD and malignancy is uncommon. In these case series, we report the remarkable case of a patient diagnosed with ISD associated with bone metastatic lesions of an unknown cancer and multiple myeloma accidentally discovered due to COVID-19 infection. We also reported two cases of ISD caused by rare organisms: the first case is a man with ISD caused by a multidrug resistant A. baumannii, and the second is a man with C. koseri bacteraemia complicated by paraspinal abscess and ISD. Resumen La espondilodiscitis infecciosa (EDI) es una infección rara de la columna vertebral, la enfermedad causada por Acinetobacter baumannii y Citrobacter koseri es aún más rara. Además, la asociación entre EDI y malignidad es un hecho poco común. En esta serie de casos presentamos el caso destacado de un paciente diagnosticado con EDI asociado con lesiones metastásicas óseas de un cáncer desconocido y mieloma múltiple de descubrimiento accidental con motivo de infección por COVID-19. También, reportamos dos casos de EDI causados por microorganismos inusuales: el primer caso es un hombre con EDI causada por Acinetobacter baumannii multirresistente, y el segundo es un hombre con bacteriemia por Citrobacter koseri complicada con absceso paraspinal y EDI.

Special Issue: Innovative strategies in predictive, preventive and personalised medicine. (Special Issue: Innovative strategies in predictive, preventive and personalised medicine.)

This special issue contains 7 articles on the principles of predictive, preventive and personalised (3P) medicine. Topics covered include: endothelin-1 and its potential as the diagnostic, prognostic and treatment target in the framework of 3P medicine;potential health risks associated specifically with the low body weight;management of COVID-19;wrist actigraphic approach;diagnosing hospital bacteraemia;and omics biomarkers in pituitary neuroendocrine tumors.

Reducing broad-spectrum antibiotic use in intensive care unit between first and second waves of COVID-19 did not adversely affect mortality.

BACKGROUND: The COVID-19 pandemic increased the use of broad-spectrum antibiotics due to diagnostic uncertainty, particularly in critical care. Multi-professional communication became more difficult, weakening stewardship activities. AIM: To determine changes in bacterial co-/secondary infections and antibiotics used in COVID-19 patients in critical care, and mortality rates, between the first and second waves. METHODS: Prospective audit comparing bacterial co-/secondary infections and their treatment during the first two waves of the pandemic in a single-centre teaching hospital intensive care unit. Data on demographics, daily antibiotic use, clinical outcomes, and culture results in patients diagnosed with COVID-19 infection were collected over 11 months. FINDINGS: From March 9th, 2020 to September 2nd, 2020 (Wave 1), there were 156 patients and between September 3rd, 2020 and February 1st, 2021 (Wave 2) there were 235 patients with COVID-19 infection admitted to intensive care. No significant difference was seen in mortality or positive blood culture rates between the two waves. The proportion of patients receiving antimicrobial therapy (93.0% vs 81.7%; P < 0.01) and the duration of meropenem use (median (interquartile range): 5 (2-7) vs 3 (2-5) days; P = 0.01) was lower in Wave 2. However, the number of patients with respiratory isolates of Pseudomonas aeruginosa (4/156 vs 21/235; P < 0.01) and bacteraemia from a respiratory source (3/156 vs 20/235; P < 0.01) increased in Wave 2, associated with an outbreak of infection. There was no significant difference between waves with respect to isolation of other pathogens. CONCLUSION: Reduced broad-spectrum antimicrobial use in the second wave of COVID-19 compared with the first wave was not associated with significant change in mortality.

Australian Group on Antimicrobial Resistance (AGAR) Australian Enterococcal Sepsis Outcome Programme (AESOP) Annual Report 2020.

From 1 January to 31 December 2020, forty-nine institutions around Australia participated in the Australian Enterococcal Sepsis Outcome Programme (AESOP). The aims of AESOP 2020 were to determine the proportion of enterococcal bacteraemia isolates in Australia that were antimicrobial-resistant, and to characterise the molecular epidemiology of the E. faecium isolates. Of the 1,230 unique episodes of enterococcal bacteraemia investigated, 93.9% were caused by either E. faecalis (54.2%) or E. faecium (39.7%). Ampicillin resistance was not detected in E. faecalis but was detected in 88.2% of E. faecium . Vancomycin non-susceptibility was detected in 0.2% of E. faecalis and 32.6% of E. faecium . Overall, 35.2% of E. faecium harboured vanA and/or vanB genes. For the vanA/B positive E. faecium isolates, 38.8% harboured the vanA gene, 60.6% the vanB gene, and 0.6% harboured both vanA and vanB . Although the percentage of E. faecium bacteraemia isolates was significantly lower than that detected in the 2019 AESOP (presumably due to the COVID-19 elective surgery restrictions placed on hospitals), it remains substantially higher than that recorded in most European countries. The E. faecium isolates detected consisted of 71 multilocus sequence types (STs), with 81.7% of these isolates classified into eight major STs each containing ten or more isolates. All major STs belonged to clonal cluster 17 (CC17), a major hospital-adapted polyclonal E. faecium cluster. The major STs (ST17, ST1424, ST80, ST796, ST78, ST1421, ST555 and ST117) were found across most regions of Australia. The predominant clone was ST17, which was identified in all regions except the Northern Territory. Overall, 40.9% of isolates belonging to the eight major STs harboured the vanA or vanB gene. The AESOP 2020 has shown enterococcal bacteraemia episodes in Australia are frequently caused by polyclonal ampicillin-resistant high-level gentamicin-resistant vanA - or vanB -positive E. faecium which have limited treatment options.

Social distancing and bacteraemia in the time of COVID-19.

BACKGROUND: Social distancing was the predominant strategy used to mitigate the spread of Coronavirus disease 2019 (COVID-19) at the start of the COVID-19 pandemic. AIMS: To study the impact of social distancing on the incidence of bacteraemia. The number of admitted patients with positive blood cultures in April-May 2020 in one tertiary medical centre was compared with the number during the same period in the previous 3 years (April-May 2017-2019). METHODS: Retrospective review of all positive blood cultures from January to July in the years 2017-2020. RESULTS: There were fewer cases of Streptococcus bacteraemia as well as coagulase-negative Staphylococcus bacteraemia and other possible contaminated blood cultures in April-May 2020. Compared with the previous 3 years, the incidence of Streptococcus pneumoniae bacteraemia among all bacteraemias was lower in April-May 2020 (5%) than in 2017-2019 (12.0%; 95% confidence interval 10.3-14.1%). In general, fewer cases of bacteraemia caused by oropharynx organisms were observed in April-May 2020; only 6 cases versus 31 (95% confidence interval 10-53) during the same period in 2017-2019. Only one case of S. pneumoniae bacteraemia was observed in April-May 2020 and its percentage among all bacteraemias was lower in April-May 2020 (0.4%) than during the same period in 2017-2019 (3.3%). CONCLUSION: The incidences of streptococcal bacteraemia and bacteraemia of organisms transmitted through respiratory secretions were lower when there were social distancing restrictions. Adopting measures of social distancing may decrease the morbidity from bacteraemia caused by oropharynx and respiratory bacteria.

Rising rates of hospital-onset Klebsiella spp. and Pseudomonas aeruginosa bacteraemia in NHS acute trusts in England: a review of national surveillance data, August 2020-February 2021.

Increases in hospital-onset Klebsiella spp. and Pseudomonas aeruginosa bacteraemia rates in England were observed between August 2020 and February 2021 to the highest levels recorded since the start of mandatory surveillance in April 2017. Cases were extracted from England's mandatory surveillance database for key Gram-negative bloodstream infections. Incidence rates for hospital-onset bacteraemia cases increased from 8.9 (N=255) to 14.9 (N=394) per 100,000 bed-days for Klebsiella spp. [incidence rate ratio (IRR) 1.7, P<0.001], and from 4.9 (N=139) to 6.2 (N=164) per 100,000 bed-days for P. aeruginosa (IRR 1.3, P<0.001) (August 2020-February 2021). These incidence rates were higher than the average rates observed during the same period in the previous 3 years. These trends coincided with an increase in the percentage of hospital-onset bacteraemia cases that were also positive for severe acute respiratory syndrome coronavirus-2.

Diagnosing hospital bacteraemia in the framework of predictive, preventive and personalised medicine using electronic health records and machine learning classifiers.

Background: The bacteraemia prediction is relevant because sepsis is one of the most important causes of morbidity and mortality. Bacteraemia prognosis primarily depends on a rapid diagnosis. The bacteraemia prediction would shorten up to 6 days the diagnosis, and, in conjunction with individual patient variables, should be considered to start the early administration of personalised antibiotic treatment and medical services, the election of specific diagnostic techniques and the determination of additional treatments, such as surgery, that would prevent subsequent complications. Machine learning techniques could help physicians make these informed decisions by predicting bacteraemia using the data already available in electronic hospital records. Objective: This study presents the application of machine learning techniques to these records to predict the blood culture's outcome, which would reduce the lag in starting a personalised antibiotic treatment and the medical costs associated with erroneous treatments due to conservative assumptions about blood culture outcomes. Methods: Six supervised classifiers were created using three machine learning techniques, Support Vector Machine, Random Forest and K-Nearest Neighbours, on the electronic health records of hospital patients. The best approach to handle missing data was chosen and, for each machine learning technique, two classification models were created: the first uses the features known at the time of blood extraction, whereas the second uses four extra features revealed during the blood culture. Results: The six classifiers were trained and tested using a dataset of 4357 patients with 117 features per patient. The models obtain predictions that, for the best case, are up to a state-of-the-art accuracy of 85.9%, a sensitivity of 87.4% and an AUC of 0.93. Conclusions: Our results provide cutting-edge metrics of interest in predictive medical models with values that exceed the medical practice threshold and previous results in the literature using classical modelling techniques in specific types of bacteraemia. Additionally, the consistency of results is reasserted because the three classifiers' importance ranking shows similar features that coincide with those that physicians use in their manual heuristics. Therefore, the efficacy of these machine learning techniques confirms their viability to assist in the aims of predictive and personalised medicine once the disease presents bacteraemia-compatible symptoms and to assist in improving the healthcare economy.

Immunomodulatory therapy, risk factors and outcomes of hospital-acquired bloodstream infection in patients with severe COVID-19 pneumonia: a Spanish case-control matched multicentre study (BACTCOVID).

OBJECTIVES: The effect of the use of immunomodulatory drugs on the risk of developing hospital-acquired bloodstream infection (BSI) in patients with COVID-19 has not been specifically assessed. We aim to identify risk factors for, and outcomes of, BSI among hospitalized patients with severe COVID-19 pneumonia. METHODS: We performed a severity matched case-control study (1:1 ratio) nested in a large multicentre prospective cohort of hospitalized adults with COVID-19. Cases with BSI were identified from the cohort database. Controls were matched for age, sex and acute respiratory distress syndrome. A Cox proportional hazard ratio model was performed. RESULTS: Of 2005 patients, 100 (4.98%) presented 142 episodes of BSI, mainly caused by coagulase-negative staphylococci, Enterococcus faecalis and Pseudomonas aeruginosa. Polymicrobial infection accounted for 23 episodes. The median time from admission to the first episode of BSI was 15 days (IQR 9-20), and the most frequent source was catheter-related infection. The characteristics of patients with and without BSI were similar, including the use of tocilizumab, corticosteroids, and combinations. In the multivariate analysis, the use of these immunomodulatory drugs was not associated with an increased risk of BSI. A Cox proportional hazard ratio (HR) model showed that after adjusting for the time factor, BSI was associated with a higher in-hospital mortality risk (HR 2.59; 1.65-4.07; p < 0.001). DISCUSSION: Hospital-acquired BSI in patients with severe COVID-19 pneumonia was uncommon and the use of immunomodulatory drugs was not associated with its development. When adjusting for the time factor, BSI was associated with a higher mortality risk.

Association Between Early Antibiotic Therapy and In-Hospital Mortality Among Older Patients With SARS-CoV-2 Pneumonia.

BACKGROUND: It is uncertain whether antibiotic therapy should be started in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia. We aimed to investigate the association between early antibiotic therapy and the risk of in-hospital mortality in older patients. METHODS: We performed a retrospective international cohort study (ANTIBIOVID) in 5 coronavirus disease 2019 geriatric units in France and Switzerland. Among 1357 consecutive patients aged 75 or older hospitalized and testing positive for SARS-CoV-2, 1072 had radiologically confirmed pneumonia, of which 914 patients were still alive and hospitalized at 48 hours. To adjust for confounders, a propensity score for treatment was created, and stabilized inverse probability of treatment weighting (SIPTW) was applied. To assess the association between early antibiotic therapy and in-hospital 30-day mortality, SIPTW-adjusted Kaplan-Meier and Cox proportional hazards regression analyses were performed. RESULTS: Of the 914 patients with SARS-CoV-2 pneumonia, median age of 86, 428 (46.8%) received antibiotics in the first 48 hours after diagnosis. Among these patients, 147 (34.3%) died in hospital within 1 month versus 118 patients (24.3%) with no early antibiotic treatment. After SIPTW, early antibiotic treatment was not significantly associated with mortality (adjusted hazard ratio, 1.23; 95% confidence interval, 0.92-1.63; p = .160). Microbiologically confirmed superinfections occurred rarely in both groups (bacterial pneumonia: 2.5% vs 1.5%, p = .220; blood stream infection: 8.2% vs 5.2%, p = .120; Clostridioides difficile colitis: 2.4% vs 1.0%, p = .222). CONCLUSIONS: In a large multicenter cohort of older inpatients with SARS-CoV-2 pneumonia, early antibiotic treatment did not appear to be associated with an improved prognosis.

Not All Pulmonary Densifications Are COVID-19: A Case Report About Lemierre's Syndrome.

Lemierre's syndrome is a rare and a life-threatening disease characterized by anaerobic bacteraemia associated with thrombosis of the internal jugular vein. Odynophagia, otalgia, odontalgia, dyspnoea, cough and fever are the most frequent manifestations. We describe a case of a 37-year-old woman who was admitted to the emergency room due to fever, odynophagia, dyspnoea, myalgia, and pleuritic chest pain. She had hypoxaemia and increased systemic inflammatory markers. The chest CT showed parenchymal densification compatible with severe acute respiratory syndrome coronavirus infection, although all three polymerase chain reaction testing were negative. The neck CT showed occlusion of the left cervical internal jugular vein. She was treated with antibiotics and was discharged. With the reported clinical case the authors intend to clarify the importance of differential diagnosis and the diagnosis of other infectious respiratory conditions at the time of a global pandemic.

Multidrug-resistant Acinetobacter baumannii infections in COVID-19 patients hospitalized in intensive care unit.

OBJECTIVES: Superinfections in patients hospitalized in intensive care unit (ICU) are an important and challenging complication, also in COVID-19. However, no definitive data are available about the role of multidrug-resistant Acinetobacter baumannii (MDR-AB) in COVID-19. METHODS: This was a single-center, cross-sectional study including patients with MDR-AB infections admitted to ICU with or without COVID-19, between January 2019 and January 2021. The primary objective of the study was to evaluate risk factor for MDR-AB infections in ICU patients hospitalized for COVID-19 or other etiology. The secondary endpoints were 30-days mortality in all study population and risk factors associated with development of bloodstream infection (BSI). RESULTS: During the study period 32 adults with COVID-19 were enrolled and compared with 115 patients admitted in the same ICU for other reasons. We observed a total of 114 deaths, with a survival rate of 29.3%: 18.8% in COVID-19 and 32.2% in control group. Relative risk for MDR-AB infection in COVID-19 showed that serum lactate levels mmol/l > 2, Acinetobacter baumannii colonization, BSI and steroid therapy were observed more frequently in COVID-19 patients. Cox regression analysis showed that serum lactate levels > 2 mmol/l, Acinetobacter baumannii colonization, BSI, and steroid therapy were associated with 30-days mortality. Finally, patients with COVID-19, white blood cells count > 11,000 mm3, serum lactate levels > 2 mmol/l, infections at time of ICU admission, Acinetobacter baumannii colonization, and steroid therapy were independently associated with development of BSI. CONCLUSIONS: Our data highlight the impact of BSI on outcome, the role of Acinetobacter baumannii colonization and the use of steroids on the risk to develop MDR-AB infections also during COVID-19.

The Role of Immunological and Clinical Biomarkers to Predict Clinical COVID-19 Severity and Response to Therapy-A Prospective Longitudinal Study.

Background: The association of pro-inflammatory markers such as interleukin-6 (IL-6) and other biomarkers with severe coronavirus disease 2019 (COVID-19) is of increasing interest, however their kinetics, response to current COVID-related treatments, association with disease severity and comparison with other disease states associated with potential cytokine storm (CS) such as Staphylococcus aureus bacteraemia (SAB) are ill-defined. Methods: A cohort of 55 hospitalized SARS-CoV-2 positive patients was prospectively recruited - blood sampling was performed at baseline, post-treatment and hospital discharge. Serum IL-6, C-reactive protein (CRP) and other laboratory investigations were compared between treatment groups and across timepoints. Acute serum IL-6 and CRP levels were then compared to those with suspected COVID-19 (SCOVID) and age and sex matched patients with SAB and patients hospitalized for any non-infectious condition (NIC). Results: IL-6 was elevated at admission in the SARS-CoV-2 cohort but at lower levels compared to matched SAB patients. Median (IQR) IL-6 at admission was 73.89 pg/mL (30.9, 126.39) in SARS-CoV-2 compared to 92.76 pg/mL (21.75, 246.55) in SAB (p=0.017); 12.50 pg/mL (3.06, 35.77) in patients with NIC; and 95.51 pg/mL (52.17, 756.67) in SCOVID. Median IL-6 and CRP levels decreased between admission and discharge timepoints. This reduction was amplified in patients treated with remdesivir and/or dexamethasone. CRP and bedside vital signs were the strongest predictors of COVID-19 severity. Conclusions: Knowledge of the kinetics of IL-6 did not offer enhanced predictive value for disease severity in COVID-19 over common investigations such as CRP and vital signs.