Efficacy of an antimicrobial stewardship intervention for early adaptation of antibiotic therapy in high-risk neutropenic patients

BACKGROUND

The 4th European Conference on Infections in Leukemia recommends early adaptation of empirical antibiotic therapy (EAT) for febrile neutropenia in stable patients.

OBJECTIVES

To assess the efficacy of an antimicrobial stewardship (AMS) intervention promoting early de-escalation and discontinuation of EAT in high-risk neutropenic patients.

METHODS

This before-after study was conducted in the hematology department of the University Hospital of Nice, France. The AMS intervention included the development of clinical decision support algorithms, a twice-weekly face-to-face review of all antibiotic prescriptions and monthly feedback on the intervention. The primary endpoint was overall antibiotic consumption during hospital stay, expressed as days of therapy (DOT).

RESULTS

A total of 113 admissions were included: 56 during the pre-intervention period and 57 during the intervention period. Induction chemotherapy and conditioning for allogeneic stem cell transplantation were the most frequent reasons for admission. In the intervention period, there was a significant decrease in overall antibiotic consumption (median DOT 20 vs. 28 days, p = 0.006), carbapenem consumption (median DOT 5.5 vs. 9 days, p = 0.017) and anti-resistant Gram-positive agents consumption (median DOT 8 vs. 11.5 days, p = 0.017). We found no statistical difference in the rates of intensive care unit admission (9% in each period) and 30-day mortality (5% vs. 0%, p = 0.243). Compliance with de-escalation and discontinuation strategies was significantly higher in the intervention period (77% vs. 8%, p < 0.001).

CONCLUSION

A multifaceted AMS intervention led to high compliance with early de-escalation and discontinuation of EAT and lower overall antibiotic consumption, without negatively affecting clinical outcomes.

Effects of antimicrobial therapy duration and class on risk of antimicrobial-resistant Gram-negative bacillus bloodstream infection in patients with AML

BACKGROUND

Antimicrobial-resistant Gram-negative bacilli (ARGNB) bloodstream infection (BSI) has been associated with prior antibiotic exposure among hematologic malignancy patients. The relationships between days of therapy (DOT), antimicrobial class, and ARGNB BSI risk are poorly understood.

METHODS

This is a single-center, case-control study of acute myeloid leukemia (AML) patients including 115 cases with ARGNB BSI and 230 matched controls with non-ARGNB BSI between January 1, 2007 and December 31, 2018. Fixed- and mixed-effects logistic regression was used to examine relationships between antibiotic DOT and risk of ARGNB BSI. Admission to an intensive care unit (ICU) within 7 days, 30-day mortality, and Pitt Bacteremia Score (PBS) were secondary outcomes.

RESULTS

Prior isolation of a antimicrobial-resistant organism (ARO) (OR 4.45 95% CI 1.46, 13.54), surgery within 90 days (OR 3.71, 95% CI 1.57, 8.73), aminoglycoside DOT (OR 1.14, 95% CI 1.05, 1.23), cefepime DOT (OR 1.09, 95% CI 1.05, 1.13), and carbapenem DOT (OR 1.10, 95% CI 1.05, 1.16) were associated with increased odds of ARGNB BSI. Days since last antibiotic administration (OR 0.98, 95% CI 0.97, 0.99) and inpatient days within 90 days (OR 0.95, 95% CI 0.93, 0.98) showed reduced odds of ARGNB BSI. Total antimicrobial DOT regardless of class was not associated with ARGNB BSI. ARGNB BSI was associated with increased 30-day mortality (OR 2.86, 95% CI 1.57, 5.22) CONCLUSIONS: Among AML patients with GNB BSI, greater DOT of aminoglycosides, cefepime, and carbapenems in the 90 days prior to BSI were associated with increased odds of ARGNB BSI.

Bloodstream gram-negative bacterial infections in adult patients with leukemia: A retrospective review of medical records in a tertiary care hospital in Western Saudi Arabia

BACKGROUND

Patients with neutropenic cancers are at high risk of acquiring infections, especially if on chemotherapy. Gram-negative bacterial infections are associated with high mortality. This study aimed to assess clinical characteristics, outcomes, and epidemiology of gram-negative bacterial (GNB) bloodstream infections (BSI) in adult patients with leukemia.

METHODS

This single-center, retrospective study included 102 adult patients diagnosed with leukemia between 2017 and 2019. The patients' demographics, infection diagnosis, leukemia diagnosis, comorbidities, and infection outcomes were collected from electronic medical records.

RESULTS

The most common GNB were Klebsiella pneumoniae (33.3 %), Pseudomonas aeruginosa (23.5 %), and Escherichia coli (17.6 %). Additionally, 36.7 % of infections were multidrug resistant. The most common comorbidities were cardiovascular diseases (36.7 %), diabetes mellitus (33.3 %), and liver diseases (24.1 %). GNB-infected patients had a higher mortality than noninfected patients (35.3 % and 11.8 %, respectively, p = 0.005). In a multivariable analysis, patients with acute myeloid leukemia and acute lymphoid leukemia were significantly more likely to acquire GNB BSI (p = 0.01), while patients with chronic myelogenous leukemia and chronic lymphocytic leukemia had a lower likelihood of developing GNB BSI. In addition, low hemoglobin level was an independent risk factor of GNB BSI (p = 0.001). Chemotherapeutic agents showed an association with increased risk of GNB BSI.

CONCLUSIONS

Patients with acute leukemia and low hemoglobin levels have increased risk of GNB BSI, which was associated with increased mortality. Prospective studies are needed to further assess the effect of co-morbidities and chemotherapy medications on the occurrence of GNB BSI according to the type of leukemia.

Bloodstream Infections Caused by Multidrug Resistant Bacteria: Clinical and Microbiological Features and Mortality

Objectives

Bloodstream infections (BSI) are associated with high morbidity and mortality. The aim of our study is to determine whether there is a relationship between certain risk factors such as the underlying disease, patient's medical history, or interventional procedures and multidrug resistant (MDR) bacterial infection and to determine the risk factors for mortality.

Methods

Two hundred and twenty-two outpatients and inpatients who were diagnosed with bacteremia over a 6-month period were included in the study. 232 agents from 222 patients were isolated and tested for antimicrobial susceptibility. The relationship between patients demographic and clinical data and MDR was analyzed.

Results

The most common microorganisms were Gram-negative bacteria (59.4%), Gram-positive bacteria (36.9%), Candida species (2.2%), and anaerobic bacteria (1.35%). The most common isolates were Escherichia coli 53 (22.8%), Staphylococcus aureus 35 (%15.1), Klebsiella pneumoniae 26 (11.2%), Pseudomonas spp. (n=17, 7.3%), Acinetobacter spp 17 (7.3%), and Enterococcus spp 14 (6%). Microorganisms with the highest antimicrobial resistance observed were 82.3% in Acinetobacter baumannii, 64.5% in coagulase-negative staphylococci, 60.3% in E. coli, 50% in K. pneumoniae, and 27.2% in Enterobacterales spp. Most patients with BSI caused by MDR bacteria were in the intensive care unit (64%). Sepsis diagnosis, urinary catheter use, history of surgery, and use of broad-spectrum antibiotics as well as risk factors for antibiotic-resistant bacteremia, coronary artery disease, inappropriate empirical therapy, healthcare-associated infections, urinary catheterization, and stay in the ICU were determined as risk factors for mortality.

Conclusion

Our study identified the risk factors of BSI caused by MDR bacteria and helped to reveal the relationship between these factors and mortality.

Prospective analysis of febrile neutropenia patients with bacteraemia: the results of an international ID-IRI study

OBJECTIVES

Bacteraemia during the course of neutropenia is often fatal. We aimed to identify factors predicting mortality to have an insight into better clinical management.

METHODS

The study has a prospective, observational design using pooled data from febrile neutropenia patients with bacteraemia in 41 centres in 16 countries. Polymicrobial bacteraemias were excluded. It was performed through the Infectious Diseases-International Research Initiative platform between 17 March 2021 and June 2021. Univariate analysis followed by a multivariate binary logistic regression model was used to determine independent predictors of 30-d in-hospital mortality (sensitivity, 81.2%; specificity, 65%).

RESULTS

A total of 431 patients were enrolled, and 85 (19.7%) died. Haematological malignancies were detected in 361 (83.7%) patients. Escherichia coli (n = 117, 27.1%), Klebsiellae (n = 95, 22% %), Pseudomonadaceae (n = 63, 14.6%), Coagulase-negative Staphylococci (n = 57, 13.2%), Staphylococcus aureus (n = 30, 7%), and Enterococci (n = 21, 4.9%) were the common pathogens. Meropenem and piperacillin-tazobactam susceptibility, among the isolated pathogens, were only 66.1% and 53.6%, respectively. Pulse rate (odds ratio [OR], 1.018; 95% confidence interval [CI], 1.002-1.034), quick SOFA score (OR, 2.857; 95% CI, 2.120-3.851), inappropriate antimicrobial treatment (OR, 1.774; 95% CI, 1.011-3.851), Gram-negative bacteraemia (OR, 2.894; 95% CI, 1.437-5.825), bacteraemia of non-urinary origin (OR, 11.262; 95% CI, 1.368-92.720), and advancing age (OR, 1.017; 95% CI, 1.001-1.034) were independent predictors of mortality. Bacteraemia in our neutropenic patient population had distinctive characteristics. The severity of infection and the way to control it with appropriate antimicrobials, and local epidemiological data, came forward.

CONCLUSIONS

Local antibiotic susceptibility profiles should be integrated into therapeutic recommendations, and infection control and prevention measures should be prioritised in this era of rapidly increasing antibiotic resistance.

Oral colonization by gram-negative bacilli in patients with hematologic malignancies and solid tumors compared with healthy controls

BACKGROUND

Colonization of the oropharynx with gram-negative bacilli (GNB) is considered a negative prognostic factor in immunocompromised individuals. Hemato-oncologic patients represent a high-risk group due to their immunodeficiencies and associated treatments. This study aimed to determine the rates of oral colonization by GNB, associated factors, and clinical outcomes in patients with hematologic malignancies and solid tumors compared with healthy subjects.

METHODS

We conducted a comparative study of hemato-oncologic patients and healthy subjects from August to October 2022. Swabs were taken from the oral cavity; specimens with GNB were identified and tested for antimicrobial susceptibility.

RESULTS

We included 206 participants (103 hemato-oncologic patients and 103 healthy subjects). Hemato-oncologic patients had higher rates of oral colonization by GNB (34% vs. 17%, P = 0.007) and GNB resistant to third-generation cephalosporins (11.6% vs. 0%, P < 0.001) compared to healthy subjects. Klebsiella spp. was the predominant genus in both groups. The factor associated with oral colonization by GNB was a Charlson index ≥ 3, while ≥ 3 dental visits per year were a protective factor. Regarding colonization by resistant GNB in oncology patients, antibiotic therapy and a Charlson index ≥ 5 were identified as associated factors, while better physical functionality (ECOG ≤ 2) was associated with less colonization. Hemato-oncologic patients colonized with GNB had more 30-day infectious complications (30.5% vs. 2.9%, P = 0.0001) than non-colonized patients.

CONCLUSION

Oral colonization by GNB and resistant GNB are prevalent in cancer patients, especially those with higher scores on the severity scales. Infectious complications occurred more frequently in colonized patients. There is a knowledge gap about dental hygiene practices in hemato-oncologic patients colonized by GNB. Our results suggest that patients' hygienic-dietary habits, especially frequent dental visits, are a protective factor against colonization.

Evaluation of a safe neutrophil count for cessation of intravenous antibiotics and early hospital discharge in stable, afebrile patients recovering after acute myeloid leukemia therapy or an autograft

Currently there are no guidelines on a safe neutrophil count(ANC) for intravenous antibiotic(IVAB) cessation and hospital discharge in patients recovering after febrile neutropenia(FN). We assessed the safety in selected patients after recent FN of prompt IVAB cessation and hospital discharge. Safety was defined as no fever recurrence after IVAB cessation and readmission in the 10-days post-discharge for infections.A retrospective, single center audit conducted on 92 adult hematology patients admitted with de novo acute myeloid leukemia (AML) for intensive chemotherapy or for an autograft. Most admissions (n = 128/141;91%) were complicated by FN. Half of FN episodes ceased IVAB promptly with a median(range) ANC of 0.6(0.1-4.9x109/L); none of these episodes had recurrent fever requiring IVAB resumption. Prompt discharge occurred in 45% overall. Subsequent unplanned readmission rates were low.In afebrile, stable AML and autograft patients without medico-social barriers to discharge, IVAB can be ceased and hospital discharges safely done ≤24h of ANC ≥ 0.2x109/L.

Mortality due to Multidrug-Resistant Gram-Negative Bacteremia in an Endemic Region: No Better than a Toss of a Coin

The incidence of multidrug-resistant (MDR) bloodstream infections (BSIs) is associated with high morbidity and mortality. Little evidence exists regarding the epidemiology of BSIs and the use of appropriate empirical antimicrobial therapy in endemic regions. Novel diagnostic tests (RDTs) may facilitate and improve patient management. Data were assessed from patients with MDR Gram-negative bacteremia at a university tertiary hospital over a 12-month period. In total, 157 episodes of MDR Gram-negative BSI were included in the study. The overall mortality rate was 50.3%. Rapid molecular diagnostic tests were used in 94% of BSI episodes. In univariate analysis, age (OR 1.05 (95% CI 1.03, 1.08) p < 0.001), Charlson Comorbidity Index (OR 1.51 (95% CI 1.25, 1.83) p < 0.001), procalcitonin ≥ 1(OR 3.67 (CI 95% 1.73, 7.79) p < 0.001), and monotherapy with tigecycline (OR 3.64 (95% CI 1.13, 11.73) p = 0.030) were the only factors associated with increased overall mortality. Surprisingly, time to appropriate antimicrobial treatment had no impact on mortality. MDR pathogen isolation, other than Klebsiella pneumoniae and Acinetobacter baumanii, was associated with decreased mortality (OR 0.35 (95% CI 0.16, 0.79) p = 0.011). In multivariate analysis, the only significant factor for mortality was procalcitonin ≥ 1 (OR 2.84 (95% CI 1.13, 7.11) p = 0.025). In conclusion, in an endemic area, mortality rates in MDR BSI remain notable. High procalcitonin was the only variable that predicted death. The use of rapid diagnostics did not improve mortality rate.

Temperature Trajectory Subphenotypes in Oncology Patients with Neutropenia and Suspected Infection

Rationale: Despite etiologic and severity heterogeneity in neutropenic sepsis, management is often uniform. Understanding host response clinical subphenotypes might inform treatment strategies for neutropenic sepsis. Objectives: In this retrospective two-hospital study, we analyzed whether temperature trajectory modeling could identify distinct, clinically relevant subphenotypes among oncology patients with neutropenia and suspected infection. Methods: Among adult oncologic admissions with neutropenia and blood cultures within 24 hours, a previously validated model classified patients' initial 72-hour temperature trajectories into one of four subphenotypes. We analyzed subphenotypes' independent relationships with hospital mortality and bloodstream infection using multivariable models. Measurements and Main Results: Patients (primary cohort n = 1,145, validation cohort n = 6,564) fit into one of four temperature subphenotypes. "Hyperthermic slow resolvers" (pooled n = 1,140 [14.8%], mortality n = 104 [9.1%]) and "hypothermic" encounters (n = 1,612 [20.9%], mortality n = 138 [8.6%]) had higher mortality than "hyperthermic fast resolvers" (n = 1,314 [17.0%], mortality n = 47 [3.6%]) and "normothermic" (n = 3,643 [47.3%], mortality n = 196 [5.4%]) encounters (P < 0.001). Bloodstream infections were more common among hyperthermic slow resolvers (n = 248 [21.8%]) and hyperthermic fast resolvers (n = 240 [18.3%]) than among hypothermic (n = 188 [11.7%]) or normothermic (n = 418 [11.5%]) encounters (P < 0.001). Adjusted for confounders, hyperthermic slow resolvers had increased adjusted odds for mortality (primary cohort odds ratio, 1.91 [P = 0.03]; validation cohort odds ratio, 2.19 [P < 0.001]) and bloodstream infection (primary odds ratio, 1.54 [P = 0.04]; validation cohort odds ratio, 2.15 [P < 0.001]). Conclusions: Temperature trajectory subphenotypes were independently associated with important outcomes among hospitalized patients with neutropenia in two independent cohorts.

Prevalence and determinants of antimicrobial resistance of pathogens isolated from cancer patients in an intensive care unit in Alexandria, Egypt

BACKGROUND

Infections caused by multidrug-resistant organisms (MDROs) are a globally increasing threat among critically ill patients, especially those with underlying malignancies. We aimed to assess the prevalence and susceptibility patterns of MDROs among cancer patients in intensive care units (ICU), and their predictors.

METHODS

Over 4 years, we retrospectively reviewed medical records of 497 malignancy patients in the ICU of a tertiary hospital in Alexandria, Egypt. The data for various factors, such as demographic characteristics, comorbidities, causative pathogen, and antimicrobial resistance (AMR), were collected and analyzed using univariate analysis. Logistic multivariate regression analysis was used to estimate the probability of developing MDROs among this population.

RESULTS

A total of 748 isolates were obtained from 1249 specimens. Gram-negative bacteria detected (459) comprised 61.4% of all isolates, while only 75 (10%) were gram-positive, and 214 (28.6%) were fungal pathogens. The most frequently encountered isolate was Klebsiella pneumoniae (n = 183), of which 107 were carbapenem-resistant (CR) and 62 were extended-spectrum beta-lactamase (ESBL)-producing. This was followed by Escherichia coli (n = 136), of which 17 were CR and 100 were ESBL-producing strains, while 3 were resistant to quinolones. Acinetobacter baumannii came in third (n = 67), with 63 being CR. The overall susceptibility of gram-negative bacteria was recorded as highest to colistin (97.3%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcal species among gram-positive bacteria were 54.6% and 33.3%, respectively, with no resistance reported to vancomycin or linezolid. Among the MDRO infection predictors were neutropenia, recent antibiotics use, and receiving chemotherapy. Neutropenia had the highest odds ratio (OR: 2.3, CI: 1.28-4.09), followed by recent antibiotics use (OR: 1.8, CI: 1.22-2.59).

CONCLUSION

Gram-negative bacilli were the most frequently reported MDROs, with resistance to higher generation cephalosporins and even carbapenems limiting antibiotic treatment options to older class antibiotics, such as colistin, with potential side effects, including nephrotoxicity. Estimating AMR probability using the prediction model of risk factors, such as neutropenia and previous antibiotics use, may be functional in the rapid identification of higher-risk patients.

Development of a combination antibiogram for empirical treatments of Pseudomonas aeruginosa at a university-affiliated teaching hospital

INTRODUCTION

The significantly higher mortality rate in the critical illness patients with Pseudomonas aeruginosa (PA) infection is linked to inappropriate selecting of empirical treatment. Traditional local antibiogram provides clinicians the resistant rate of a single antimicrobial agent to the pathogen in the specific setting. The information is valuable to the clinicians in selecting suitable empirical antibiotic therapy. However, traditional local antibiogram can only provide information for single agent empirical antibiotic not combination regimens. The combination antibiogram should be developed to facilitate the selection of appropriate antibiotics to broader the coverage rate of resistant PA.

METHODS

The susceptibility to the β-lactam antibiotics (piperacillin/tazobactam (PTZ), ceftazidime, cefepime, imipenem, or meropenem) or to those administered in combination with an aminoglycoside (gentamicin or amikacin) or fluoroquinolone (ciprofloxacin or levofloxacin) was calculated. The chi-square test was used to compare the differences of combination coverage rates between non-ICU and ICU isolates.

RESULTS

880 PA isolates were isolated during study period. The susceptibility of single agents ranged from 83.1% to 89.7%. The combination regimens containing amikacin provide the highest cover rate (98.9%-99.1%) and those containing levofloxacin provide less coverage rate (92.3%-93.9%). The susceptibility to five β-lactam single agents in ICU isolates significantly lower than non-ICU isolates. The non-ICU isolates exhibited significantly higher susceptibility to the PTZ-gentamicin (p = 0.002) and ceftazidime-gentamicin (p = 0.025) than ICU isolates.

CONCLUSION

Our results support the use of aminoglycosides instead of fluoroquinolones as additive agents in empirical combination treatments for patients with critical infections caused by PA.

Cost-Effectiveness of Targeted Prophylaxis among Allogenic Stem Cell Transplant Recipients

Bloodstream infections (BSI) are life-threatening complications for onco-hematologic patients. Fluoroquinolones prophylaxis (FQP) was recommended for patients with neutropenia. Later, it was correlated with increased resistance rates among this population and its role became debated. While the role of FQ prophylaxis is still being studied, its cost-effectiveness is also unknown. The objective of this study was to evaluate the costs and effects associated with two alternative strategies (FQP vs. no prophylaxis) for patients with hematological malignancies undergoing allogenic stem cell transplant (HSCT). A decision-tree model was built integrating retrospectively collected data from a single transplant center, part of a tertiary teaching hospital in Northern Italy. Probabilities, costs and effects were considered in the assessment of the two alternative strategies. Probabilities of colonization, BSIs, extended-spectrum beta lactamase (ESBL) and Klebsiella pneumoniae carbapenemase (KPC) BSIs and mortality associated with infection, as well as median duration of length of stay (LOS) were calculated based on data collected between 2013 and 2021. The center applied the strategy of FQP between 2013 and 2016, and of no prophylaxis between 2016 and 2021. Data on 326 patients were collected during the considered time period. Overall, the rates of colonization, BSI, KPC/ESBL BSI, and mortality were 6.8% (95% confidence interval (CI) 2.7-13.5), 42% (9.9-81.4) and 20.72 (16.67-25.26), respectively. A mean bed-day cost of 132€ was estimated. Considering no prophylaxis vs. prophylaxis, the difference in costs ranged between additional 33.61 and 80.59€ per patient, whereas the difference in effects ranged between 0.11 and 0.03 life-years (LYs) lost (around 40 and 11 days). Given the small differences in terms of costs and effects between the two strategies, no prophylaxis seems an appropriate choice. Furthermore, this analysis did not consider the broader effect on hospital ecology of multiple doses of FQP, which could provide further support for the strategy of no prophylaxis. Our results suggest that the necessity for FQP in onco-hematologic setting should be determined based on local antibiotic resistance patterns.

Evaluation of a Shotgun Metagenomics Approach for Detection of ESBL- and/or Carbapenemase-Producing Enterobacterales in Culture Negative Patients Recovered from Acute Leukemia

Patients diagnosed with acute leukemia (AL) have a weakened immune system. Infections acquired by these patients are cause for concern and especially worrisome when Gram-negative multidrug-resistant (MDR) bacteria are involved, as they are difficult to treat, especially in the case of ESBL- and/or carbapenemase-producing Enterobacterales. Culture-based approaches have been relied on over the past decades as the method of choice for the early detection of gut colonization by MDR Gram-negative bacteria. However, various studies have indicated its limited sensitivity, underlining the need for new screening procedures in onco-hematological patients. Here, we evaluated a shotgun metagenomics approach to detect ESBL- and/or carbapenemase-producing Enterobacterales in the gut of 28 patients who had recovered from AL, which were previously colonized by these bacteria but cured at the time of sampling, as judged by culture-based methods. No ESBL or carbapenemase determinants were detected among the many resistance genes found by the metagenomics approach, supporting that patients were truly decolonized, with considerable consequences for their future clinical management. Due to the relatively low number of patients available for the present investigation, further studies should be conducted to support the utility and applicability of metagenomics for the routine screening of MDR bacteria in onco-hematological patients.

Impact of Persistent Multidrug-Resistant Gram-Negative Bacteremia on Clinical Outcome and Mortality

The clinical aspects of persistent bacteremia (PB) caused by gram-negative rods (GNRs) in terms of antimicrobial resistance (AMR) and PB clearance status are unclear. This secondary analysis of a retrospective cohort study investigated differences in PB caused by Enterobacterales and glucose non-fermentative GNRs (NF-GNRs) based on AMR and PB clearance. We retrospectively surveyed medical records at Tohoku University Hospital. Patients for whom blood cultures were performed between January 2012 and December 2021 were recruited. PB cases were grouped based on AMR and PB clearance; the characteristics of PB due to each bacterial pathogen were examined. The main outcome variable was mortality. The late (30-90-day) mortality rate was significantly higher in the multidrug-resistant (MDR) group than in the non-MDR group for Enterobacterales. However, no significant difference was noted in mortality rates between NF-GNRs with and without AMR. Mortality rates tended to be higher in the non-PB-clearance group than in the clearance group for both Enterobacterales and NF-GNRs. Since the mortality rate was higher in the MDR group in the case of Enterobacterales PB, more careful management is necessary for this condition. Follow-up blood cultures and confirming the clearance of PB are useful for improving the survival rate.

Shorter antibiotic courses in the immunocompromised: the impossible dream?

BACKGROUND

A growing number of studies have demonstrated similar outcomes with shorter courses of antibiotics for bacterial infections. Immunocompromised patients are frequently excluded from these studies despite anticipated benefits associated with shortening antibiotic courses (including lower risks of antibiotic toxicity, Clostridioides difficile infection, drug-resistant pathogens, and microbiome alterations).

OBJECTIVES

To critically review the literature that assesses shorter antibiotic courses in immunocompromised patients, specifically among solid organ transplant recipients and neutropenic fever (NF) syndromes among patients on antineoplastic chemotherapy and undergoing haematopoietic cell transplant.

SOURCES

References were identified through searches of PubMed, Embase, MEDLINE, and clinical guidelines documents.

CONTENT

Among organ transplant recipients, the majority of studies assessing outcomes associated with shorter antibiotic courses have been retrospective but have demonstrated similar rates of clinically relevant endpoints. Patients with high- and low-risk NF have been well-studied, including enrolment in randomized studies, albeit with heterogeneous patient populations and outcomes assessed. Clinical improvement-guided adoption of shorter courses has been associated with fewer antibiotic days and similar rates of fever recurrence and mortality.

IMPLICATIONS

Similar to studies demonstrating efficacy in immunocompetent patients, shorter antibiotic courses should be considered for immunocompromised hosts with presumed bacterial infections. Organ recipients and patients with NF syndromes should be prioritized for study in randomized controlled clinical trials assessing shorter course therapy.

Increasing Gram-Negative Catheter-Related Bloodstream Infection in Cancer Patients

Background: We aimed to assess the incidence, etiology and outcomes of catheter-related bloodstream infection (CRBSI) in onco-hematological patients, to assess the differences between patients with hematological malignancies (HMs) and solid tumors (STs) and to identify the risk factors for Gram-negative (GN) CRBSI. Methods: All consecutive episodes of BSI in adult cancer patients were prospectively collected (2006-2020). The etiology of CRBSI was analyzed in three different 5-year periods. Risk factors for GN CRBSI were assessed in the whole cohort and separately in patients with HMs and STs. Results: Among 467 episodes of monomicrobial CRBSI, 407 were Gram-positive (GP) (87.1%), 49 GN (10.5%) and 11 fungal (2.4%). Hematological patients (369 episodes) were more frequently neutropenic and were more likely to carry central venous catheters and develop GP CRBSI. Patients with STs (98 episodes) had more comorbidities, more frequently carried port reservoirs and commonly presented more GN CRBSI. GN CRBSI significantly increased over the study period, from 5.2% to 23% (p < 0.001), whereas GP CRBSI decreased from 93.4% to 73.3% (p < 0.001). CRBSI episodes involving port reservoirs and peripherally-inserted central catheters were significantly increased (p < 0.001). The most frequent GPs were coagulase-negative staphylococci (CoNS) (57.8%) and Pseudomonas aeruginosa was the most common GN (3%). Multidrug-resistant (MDR) GN represented 32.7% of all GN CRBSIs and increased over time (p = 0.008). The independent risk factors for GN CRBSI in the whole cohort were solid tumor, chronic kidney disease and carrying a port reservoir. Carrying a port reservoir was also a risk factor in patients with STs. Health-care acquisition was identified as a risk factor for GN CRBSI in the whole cohort, as well as in patients with STs and HMs. Inadequate empirical antibiotic treatment (IEAT) occurred regardless of the etiology: 49% for GNs and 48.6% for GPs (p = 0.96). In GP CRBSI, IEAT was mainly due to inadequate coverage against CoNS (87%), whereas in GN CRBSI, IEAT was associated with multidrug resistance (54.2%). Early (48 h and 7-day) and 30-day case-fatality rates were similar when analyzed according to the type of underlying disease and etiology, except for the 30-day case-fatality rate, which was higher in the group of patients with STs compared to those with HMs (21.5% vs. 12.5%, p = 0.027). The 48 h case-fatality rate was significantly higher in patients in whom the catheter had not been removed (5.6% vs. 1%; p = 0.011), and it remained significant for GP CRBSI (6% vs. 1.3%, p = 0.023). Conclusions: GNs are an increasing cause of CRBSI in cancer patients, particularly in solid tumor patients carrying port reservoirs. Multidrug resistance among GNs is also increasing and is associated with higher rates of IEAT. Decreased 48 h survival was associated with the non-removal of the catheter. These findings should be considered when deciding on early therapeutic management for cancer patients with suspected CRBSI.

The Dutch Working Party on Antibiotic Policy (SWAB) Recommendations for the Diagnosis and Management of Febrile Neutropenia in Patients with Cancer

INTRODUCTION

This guideline was written by a multidisciplinary committee with mandated members of the Dutch Society for Infectious Diseases, Dutch Society for Hematology, Dutch Society for Medical Oncology, Dutch Association of Hospital Pharmacists, Dutch Society for Medical Microbiology, and Dutch Society for Pediatrics. The guideline is written for adults and pediatric patients.

METHOD

The recommendations are based on the answers to nine questions formulated by the guideline committee. To provide evidence-based recommendations we used all relevant clinical guidelines published since 2010 as a source, supplemented with systematic searches and evaluation of the recent literature (2010-2020) and, where necessary, supplemented by expert-based advice.

RESULTS

For adults the guideline distinguishes between high- and standard-risk neutropenia based on expected duration of neutropenia (> 7 days versus ≤ 7 days). Where possible a distinction has been made between pediatric and adult patients.

CONCLUSION

This guideline was written to aid diagnosis and management of patients with febrile neutropenia due to chemotherapy in the Netherlands. The guideline provides recommendation for children and adults. Adults patient are subdivided as having a standard- or high-risk neutropenic episode based on estimated duration of neutropenia. The most important recommendations are as follows. In adults with high-risk neutropenia (duration of neutropenia > 7 days) and in children with neutropenia, ceftazidime, cefepime, and piperacillin-tazobactam are all first-choice options for empirical antibiotic therapy in case of fever. In adults with standard-risk neutropenia (duration of neutropenia ≤ 7 days) the MASCC score can be used to assess the individual risk of infectious complications. For patients with a low risk of infectious complications (high MASCC score) oral antibiotic therapy in an outpatient setting is recommended. For patients with a high risk of infectious complications (low MASCC score) antibiotic therapy per protocol sepsis of unknown origin is recommended.

Third-generation cephalosporin resistant gram-negative bacteraemia in patients with haematological malignancy; an 11-year multi-centre retrospective study

Objectives

Among patients with haematological malignancy, bacteraemia is a common complication during chemotherapy-induced neutropenia. Resistance of gram-negative bacteria (GNB) to third-generation cephalosporins (3GC) is increasing. In order to explore the value of using surveillance cultures to guide empirical treatment e.g. choosing between carbapenem versus ceftazidime- we aimed to assess the distribution of pathogens causing bacteraemia in patients with haematological malignancy, and the proportion of 3GC-resistant GNB (3GC-R GNB) bacteraemia that was preceded by 3GC-R GNB colonization.

Methods

Using 11 years of data (2008–2018) from the Dutch national antimicrobial resistance surveillance system, we assessed the prevalence of 3GC-R GNB in episodes of bacteraemia, and the proportion of 3GC-R GNB bacteraemia that was preceded by 3GC-R GNB colonization. Colonization was defined as availability of any GNB surveillance isolate in the year before, independent of the causative micro-organism (time-paired isolates).

Results

We included 3887 patients, representing 4142 episodes of bacteraemia. GNB were identified in 715/4142 (17.3%), of which 221 (30.9%) were 3GC-R GNB. In 139 of these 221 patients a time-paired surveillance culture was available. In 76.2% (106/139) of patients these surveillance cultures already showed 3GC-R GNB isolates in the year prior to the culture date of the 3GC-R GNB positive blood isolate.

Conclusions

This multi-centre study shows that in patients with haematological malignancy, the majority of 3GC-R GNB bacteraemia is preceded by 3GC-R GNB colonization. Prospective clinical studies are needed to assess the safety and benefits of the use of surveillance-cultures to guide empirical therapy to restrict the empirical use of carbapenems in this population.

Computing antimicrobial use/antimicrobial resistance ratios: A novel way to assess inpatient antimicrobial utilization using current National Healthcare Safety Network metrics

BACKGROUND

Current methods for benchmarking inpatient antimicrobial use (AU) could benefit from combining AU with antimicrobial resistance (AR) information to provide metrics benchmarked to microbiological data; this may yield more instructive and better risk-adjusted measurements than AU and AR in isolation.

METHODS

In this retrospective single-center study, we computed facility-wide AU/AR ratios from 2019 to 2020 for specific antimicrobial agents and corresponding AR events, and compared median monthly AU/AR ratios between March 2019 through December 2019 (pre-COVID period) and March 2020 through December 2020 (COVID period). Aggregate AU was expressed as a ratio to aggregate AR events for antimicrobials that typically have activity against the AR organism and are frequently used to treat the AR organism in clinical practice. We also computed AU/AR ratios in our surgical intensive care unit in the pre-COVID period.

RESULTS

High-median facility-wide monthly AU/AR ratios were observed for intravenous vancomycin/methicillin-resistant Staphylococcus aureus, with 130.0 in the pre-COVID period and 121.3 in the COVID period (p =.520). Decreases in facility-wide median monthly AU/AR ratios were observed between periods for meropenem/ESBL Enterobacterales (20.9 vs. 7.9, p < .001), linezolid/vancomycin-resistant Enterococcus (48.5 vs. 15.8, p =.004), and daptomycin/vancomycin-resistant Enterococcus (32.2 vs. 4.8, p = .002). Increases in facility-wide median monthly AU/AR ratios were observed between periods for ceftazidime-avibactam/carbapenem-resistant Enterobacterales (0.0 vs. 3.2, p = .020) and ceftazidime-avibactam/multidrug-resistant Pseudomonas aeruginosa (0.0 vs. 4.0, p = .017). The AU/AR ratio for intravenous vancomycin/methicillin-resistant S. aureus in the surgical intensive care unit was 191.5 in the pre-COVID period.

CONCLUSIONS

AU/AR ratios may be used to supplement current AU and AR metrics. Future directions should include the development of more AU metrics benchmarked to microbiological information. AU metrics more specific to transplant infectious diseases should be developed.

Pseudomonas aeruginosa Bloodstream Infections in Patients with Cancer: Differences between Patients with Hematological Malignancies and Solid Tumors

Objectives: To assess the clinical features and outcomes of Pseudomonas aeruginosa bloodstream infection (PA BSI) in neutropenic patients with hematological malignancies (HM) and with solid tumors (ST), and identify the risk factors for 30-day mortality. Methods: We performed a large multicenter, retrospective cohort study including onco-hematological neutropenic patients with PA BSI conducted across 34 centers in 12 countries (January 2006−May 2018). Episodes occurring in hematologic patients were compared to those developing in patients with ST. Risk factors associated with 30-day mortality were investigated in both groups. Results: Of 1217 episodes of PA BSI, 917 occurred in patients with HM and 300 in patients with ST. Hematological patients had more commonly profound neutropenia (0.1 × 109 cells/mm) (67% vs. 44.6%; p < 0.001), and a high risk Multinational Association for Supportive Care in Cancer (MASCC) index score (32.2% vs. 26.7%; p = 0.05). Catheter-infection (10.7% vs. 4.7%; p = 0.001), mucositis (2.4% vs. 0.7%; p = 0.042), and perianal infection (3.6% vs. 0.3%; p = 0.001) predominated as BSI sources in the hematological patients, whereas pneumonia (22.9% vs. 33.7%; p < 0.001) and other abdominal sites (2.8% vs. 6.3%; p = 0.006) were more common in patients with ST. Hematological patients had more frequent BSI due to multidrug-resistant P. aeruginosa (MDRPA) (23.2% vs. 7.7%; p < 0.001), and were more likely to receive inadequate initial antibiotic therapy (IEAT) (20.1% vs. 12%; p < 0.001). Patients with ST presented more frequently with septic shock (45.8% vs. 30%; p < 0.001), and presented worse outcomes, with increased 7-day (38% vs. 24.2%; p < 0.001) and 30-day (49% vs. 37.3%; p < 0.001) case-fatality rates. Risk factors for 30-day mortality in hematologic patients were high risk MASCC index score, IEAT, pneumonia, infection due to MDRPA, and septic shock. Risk factors for 30-day mortality in patients with ST were high risk MASCC index score, IEAT, persistent BSI, and septic shock. Therapy with granulocyte colony-stimulating factor was associated with survival in both groups. Conclusions: The clinical features and outcomes of PA BSI in neutropenic cancer patients showed some differences depending on the underlying malignancy. Considering these differences and the risk factors for mortality may be useful to optimize their therapeutic management. Among the risk factors associated with overall mortality, IEAT and the administration of granulocyte colony-stimulating factor were the only modifiable variables.

The relationship between antibiotic agent and mortality in patients with febrile neutropenia due to Staphylococcal bloodstream infection: a multicenter cohort study

Background

Methicillin-susceptible Staphylococcus aureus (MSSA) is a common cause of bloodstream infection (BSI) in patients with febrile neutropenia, but treatment practices vary, and guidelines are not clear on the optimal regimen.

Methods

We conducted a multicenter retrospective cohort study of MSSA BSI in febrile neutropenia. We divided patients into 3 treatment groups: (1) broad-spectrum beta-lactams (ie, piperacillin-tazobactam, cefepime, meropenem); (2) narrow-spectrum beta-lactams (ie, cefazolin, oxacillin, nafcillin); and (3) combination beta-lactams (ie, both narrow- and broad-spectrum). We used multivariable logistic regression to compare 60-day mortality and bacteremia recurrence while adjusting for potential confounders.

Results

We identified 889 patients with MSSA BSI, 128 of whom had neutropenia at the time of the index culture: median age 56 (interquartile range, 43–65) years and 76 (59%) male. Of those, 56 (44%) received broad-spectrum beta-lactams, 30 (23%) received narrow-spectrum beta-lactams, and 42 (33%) received combination therapy. After adjusting for covariates, including disease severity, combination therapy was associated with a significantly higher odds for 60-day all-cause mortality compared with broad spectrum beta-lactams (adjusted odds ratio [aOR], 3.39; 95% confidence interval [CI], 1.29–8.89; P = .013) and compared with narrow spectrum beta-lactams, although the latter was not statistically significant (aOR, 3.30; 95% CI, .80–13.61; P = .071).

Conclusions

Use of combination beta-lactam therapy in patients with MSSA BSI and febrile neutropenia is associated with a higher mortality compared with treatment with broad-spectrum beta-lactam after adjusting for potential confounders. Patients in this study who transitioned to narrow-spectrum beta-lactam antibiotics did not have worse clinical outcomes compared with those who continued broad-spectrum beta-lactam therapy.

Effects of Inappropriate Administration of Empirical Antibiotics on Mortality in Adults With Bacteraemia: Systematic Review and Meta-Analysis

Introduction

Bloodstream infections are associated with high mortality rates and contribute substantially to healthcare costs, but a consensus on the prognostic benefits of appropriate empirical antimicrobial therapy (EAT) for bacteraemia is lacking.

Methods

We performed a systematic search of the PubMed, Cochrane Library, and Embase databases through July 2021. Studies comparing the mortality rates of patients receiving appropriate and inappropriate EAT were considered eligible. The quality of the included studies was assessed using Joanna Briggs Institute checklists.

Results

We ultimately assessed 198 studies of 89,962 total patients. The pooled odds ratio (OR) for the prognostic impacts of inappropriate EAT was 2.06 (P < 0.001), and the funnel plot was symmetrically distributed. Among subgroups without between-study heterogeneity (I² = 0%), those of patients with severe sepsis and septic shock (OR, 2.14), Pitt bacteraemia scores of ≥4 (OR, 1.88), cirrhosis (OR, 2.56), older age (OR, 1.78), and community-onset/acquired Enterobacteriaceae bacteraemia infection (OR, 2.53) indicated a significant effect of inappropriate EAT on mortality. The pooled adjusted OR of 125 studies using multivariable analyses for the effects of inappropriate EAT on mortality was 2.02 (P < 0.001), and the subgroups with low heterogeneity (I² < 25%) exhibiting significant effects of inappropriate EAT were those of patients with vascular catheter infections (adjusted OR, 2.40), pneumonia (adjusted OR, 2.72), or Enterobacteriaceae bacteraemia (adjusted OR, 4.35). Notably, the pooled univariable and multivariable analyses were consistent in revealing the negligible impacts of inappropriate EAT on the subgroups of patients with urinary tract infections and Enterobacter bacteraemia.

Conclusion

Although the current evidence is insufficient to demonstrate the benefits of prompt EAT in specific bacteraemic populations, we indicated that inappropriate EAT is associated with unfavorable mortality outcomes overall and in numerous subgroups. Prospective studies designed to test these specific populations are needed to ensure reliable conclusions.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021270274.

Clinical Characteristics of Bloodstream Infection in Immunosuppressed Patients: A 5-Year Retrospective Cohort Study

Introduction

Immunosuppressed patients with bloodstream infection are at risk of mortality. Our objective was to assess the independent risk factors of bloodstream infection with mortality in immunosuppressive states.

Methods

The medical data of a total of 896 patients who were hospitalized in our hospital were collected from January 2015 to December 2019. Evaluation of the independent risk factors of mortality was done by univariate and multivariate logistic regression analyses.

Results

Of the 896 immunosuppressed patients with bloodstream infection, 698 had over 60-day survivals and 198 had 60-day mortality. In our study, PCT (mean ±; standard: 11.40 ±; 31.89 µg/l vs. 62.45 ±; 17.10 µg/l, p = 0.007) and presence of age >60 years (40% vs. 14.19%, p = 0.001) were significantly different between situations with and without 60-day survivals in both univariate and multivariate logistic regression analyses. Age >60 years and PCT could be used as indicators for bloodstream infection with 60-day death in immunosuppressive states; the OR (95% CI) were 1.532 (1.099–2.135) and 2.063 (1.413–3.013), respectively. In different subgroups, PCT and age were also independent risk factors of blood system diseases, Klebsiella pneumoniae infection, diabetes, and ICU-stay subgroups.

Conclusions

Age and PCT were independently associated with mortality in immunosuppressive states, which may help to identify the highly risky situation of bloodstream infection in immunosuppressive states.

Impact of neutropenia on clinical manifestations and outcome of Staphylococcus aureus bloodstream infection - A propensity score-based overlap weight analysis in two large, prospectively evaluated cohorts

OBJECTIVE

To investigate whether neutropenia influenced mortality and long-term outcome of Staphylococcus aureus bloodstream infection (SAB).

METHODS

Data from two prospective, multicentre cohort studies (INSTINCT and ISAC) conducted in 20 tertiary care hospitals in 6 countries between 2006 and 2015 were analysed. Neutropenic and severely neutropenic patients (defined by the proxy of total white blood cell count <1000/μl and <500/μl, respectively, at onset of SAB) were compared to a control group using a propensity score model and overlap weights to adjust for baseline characteristics. Overall survival and time to SAB-related late complications (SAB recurrence, infective endocarditis, osteomyelitis, or other deep-seated manifestations) were analysed by Cox regression and competing risk analyses, respectively.

RESULTS

Of 3,187 patients, 102 were neutropenic and 70 were severely neutropenic at onset of SAB. Applying overlap weights yielded two groups of 83 neutropenic and 220 non-neutropenic patients, respectively. Baseline characteristics of these groups were exactly balanced. In the Cox regression analysis, we observed no significant difference in survival between the two groups (death during follow-up: 36.1 % in neutropenic vs. 30.6 % in non-neutropenic patients, hazard ratio 1.21 (95 % CI 0.79-1.83)). This finding remained unchanged when we considered severely neutropenic patients (hazard ratio 1.08 [0.60; 1.94]). Competing risk analysis showed a cause-specific hazard ratio (CSHR) of 0.39 (95 % CI 0.11-1.39) for SAB-related late-complications in neutropenic patients.

CONCLUSIONS

Neutropenia was not associated with a higher survival during follow-up. The lower rate of SAB-related late complications in neutropenic patients should be validated in other cohorts.

Multi-body-site colonization screening cultures for predicting multi-drug resistant Gram-negative and Gram-positive bacteremia in hematological patients

BACKGROUND

To investigate the multi-drug resistant bacteria (MDRB) colonization rate in hematological patients hospitalized for any cause using a multi-body-site surveillance approach, and determine the extent to which this screening strategy helped anticipate MDRB bloodstream infections (BSI).

METHODS

Single-center retrospective observational study including 361 admissions documented in 250 adult patients. Surveillance cultures of nasal, pharyngeal, axillary and rectal specimens (the latter two combined) were performed at admission and subsequently on a weekly basis. Blood culture samples were incubated in an automated continuous monitoring blood culturing instrument (BACTEC FX).

RESULTS

In total, 3463 surveillance cultures were performed (pharyngeal, n = 1201; axillary-rectal, n = 1200; nasal, n = 1062). MDRB colonization was documented in 122 out of 361 (33.7%) admissions corresponding to 86 patients (34.4%). A total of 149 MDRB were isolated from one or more body sites, of which most were Gram-negative bacteria, most frequently non-fermenting (n = 83) followed by Enterobacterales (n = 51). BSI were documented in 102 admissions (28%) involving 87 patients. Overall, the rate of BSI caused by MDRB was significantly higher (p = 0.04) in the presence of colonizing MDRB (16 out of 47 admissions in 14 patients) than in its absence (9 out of 55 admissions in 9 patients). Colonization by any MDRB was independently associated with increased risk of MDRB-BSI (HR, 3.70; 95% CI, 1.38-9.90; p = 0.009).

CONCLUSION

MDRB colonization is a frequent event in hematological patients hospitalized for any reason and is associated with an increased risk of MDRB BSI. The data lend support to the use of MDRB colonization surveillance cultures for predicting the occurrence of MDRB BSI in this cohort.

Establishment and validation of a nomogram to predict the in-hospital death risk of nosocomial infections in cancer patients

Background

Attributed to the immunosuppression caused by malignancy itself and its treatments, cancer patients are vulnerable to developing nosocomial infections. This study aimed to develop a nomogram to predict the in-hospital death risk of these patients.

Methods

This retrospective study was conducted at a medical center in Northwestern China. The univariate and multivariate logistic regression analyses were adopted to identify predictive factors for in-hospital mortality of nosocomial infections in cancer patients. A nomogram was developed to predict the in-hospital mortality of each patient, with receiver operating characteristic curves and calibration curves being generated to assess its predictive ability. Furthermore, decision curve analysis (DCA) was also performed to estimate the clinical utility of the nomogram.

Results

A total of 1,008 nosocomial infection episodes were recognized from 14,695 cancer patients. Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (15.5%) was the most predominant causative pathogen. Besides, multidrug-resistant strains were discovered in 25.5% of cases. The multivariate analysis indicated that Eastern Cooperative Oncology Group Performance Status 3–4, mechanical ventilation, septic shock, hypoproteinemia, and length of antimicrobial treatment < 7 days were correlated with higher in-hospital mortality. Patients who received curative surgery were correlated with favorable survival outcomes. Ultimately, a nomogram was constructed to predict the in-hospital mortality of nosocomial infections in cancer patients. The area under the curve values of the nomogram were 0.811 and 0.795 in the training and validation cohorts. The calibration curve showed high consistency between the actual and predicted in-hospital mortality. DCA indicated that the nomogram was of good clinical utility and more credible net clinical benefits in predicting in-hospital mortality.

Conclusions

Nosocomial infections stay conjoint in cancer patients, with gram-negative bacteria being the most frequent causative pathogens. We developed and verified a nomogram that could effectively predict the in-hospital death risk of nosocomial infections among these patients. Precise management of high-risk patients, early recognition of septic shock, rapid and adequate antimicrobial treatment, and dynamic monitoring of serum albumin levels may improve the prognosis of these individuals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-022-01073-3.

Early Antibiotic Discontinuation or De-escalation in High-Risk Patients With AML With Febrile Neutropenia and Prolonged Neutropenia

BACKGROUND

There is minimal data evaluating the safety of antibiotic de-escalation in patients with acute myeloid leukemia (AML) with fever and ongoing neutropenia. Therefore, this study evaluated antibiotic prescribing, infection-related outcomes, and patient outcomes of an antibiotic de-escalation initiative.

PATIENTS AND METHODS

This pre-post quasiexperimental study included adult patients with AML hospitalized with febrile neutropenia. An antibiotic de-escalation guideline was implemented in January 2017, which promoted de-escalation or discontinuation of intravenous antipseudomonal β-lactams. The primary outcome assessment was the incidence of bacterial infection in a historical control group before guideline implementation compared with an intervention group after guideline implementation.

RESULTS

A total of 93 patients were included. Antibiotic de-escalation occurred more frequently in the intervention group (71.7% vs 7.5%; P<.001), which resulted in fewer days of therapy for intravenous antipseudomonal β-lactams (14 vs 25 days; P<.001). Thirty-day all-cause mortality and length of hospitalization were not different between groups. However, the intervention group had significantly fewer episodes of Clostridioides difficile colitis (5.7% vs 27.5%; P=.007).

CONCLUSIONS

Implementation of an antibiotic de-escalation guideline resulted in decreased use of intravenous antipseudomonal β-lactams and fewer episodes of C difficile colitis, without adversely impacting patient outcomes. Additional studies are needed, preferably in the form of randomized controlled trials, to confirm these results.

Efficacy of antibiotic short course for bloodstream infections in acute myeloid leukemia patients with febrile neutropenia: A retrospective comparative study

OBJECTIVES

There is no specific recommendation about antimicrobial treatment length for documented infections in chemotherapy induced febrile neutropenia (FN). Practices have changed along time in our center regarding length of antibiotic treatment. The aim of this study was to compare long versus short antibiotic course for bloodstream infection (BSI) treatment in acute myeloid leukemia (AML) patients during FN.

METHODS

This monocentric retrospective comparative study included all consecutive BSI episodes among AML patients with FN for 3 years (2017-2019). Episodes were classified regarding the length of antibiotic treatment, considered as short course if the treatment lasted ≤ 7 days, except for nonfermenting bacteria and Staphylococcus aureus or lugdunensis for which the threshold was ≤ 10 days and ≤ 14 days, respectively. The primary outcome was the number of BSI relapses in both groups within 30 days of antibiotic discontinuation.

RESULTS

Among 71 AML patients, 104 BSI episodes were included; 48 (46%) received short course treatment. Only 8 (7.6%) BSI episodes relapsed within 30 days of antibiotic discontinuation, 5 having received short course treatment. No association was found between risk of relapse and short course of antibiotic treatment (p = 0.37). The only risk factor significantly associated with BSI relapse was neutropenia duration (p = 0.005).

CONCLUSION

Antibiotic short course seemed as effective as prolonged treatment for BSI in AML patients during FN, with very few relapses at day 30. These encouraging findings should be confirmed through prospective studies.

Safety & efficacy of antibiotic de-escalation and discontinuation in high-risk haematological patients with febrile neutropenia: a single-centre experience

Background

There is currently no consensus on optimal duration of antibiotic treatment in febrile neutropenia. We report on the clinical impact of implementation of antibiotic de-escalation and discontinuation strategies based on the Fourth European Conference on Infections in Leukaemia (ECIL-4) recommendations in high-risk hematological patients.

Methods

We studied 446 admissions after introduction of an ECIL-4–based protocol (hereafter “ECIL-4 group”) in comparison to a historic cohort of 512 admissions. Primary clinical endpoints were the incidence of infectious complications including septic shock, infection-related intensive care unit (ICU) admission, and overall mortality. Secondary endpoints included the incidence of recurrent fever, bacteremia, and antibiotic consumption.

Results

Bacteremia occurred more frequently in the ECIL-4 group (46.9% [209/446] vs 30.5% [156/512]; P < .001), without an associated increase in septic shock (4.7% [21/446] vs 4.5% [23/512]; P = .878) or infection-related ICU admission (4.9% [22/446] vs 4.1% [21/512]; P = .424). Overall mortality was significantly lower in the ECIL-4 group (0.7% [3/446] vs 2.7% [14/512]; P = .016), resulting mainly from a decrease in infection-related mortality (0.4% [2/446] vs 1.8% [9/512]; P = .058). Antibiotic consumption was significantly reduced by a median of 2 days on antibiotic therapy (12 vs 14; P = .001) and 7 daily antibiotic doses (17 vs 24; P < .001) per admission period.

Conclusions

Our results support implementation of ECIL-4 recommendations to be both safe and effective based on real-world data in a large high-risk patient population. We found no increase in infectious complications and total antibiotic exposure was significantly reduced.

Impact of empirical antibiotic regimens on mortality in neutropenic patients with bloodstream infection presenting with septic shock

Objectives: We analyzed risk factors for mortality in febrile neutropenic patients with bloodstream infections (BSI) presenting with septic shock and assessed the impact of empirical antibiotic regimens. Methods: Multicenter retrospective study (2010-2019) of two prospective cohorts comparing BSI episodes in patients with or without septic shock. Multivariate analysis was performed to identify independent risk factors for mortality in episodes with septic shock. Results: Of 1563 patients with BSI, 257 (16%) presented with septic shock. Those patients with septic shock had higher mortality than those without septic shock (55% vs 15%, p<0.001). Gram-negative bacilli caused 81% of episodes with septic shock; gram-positive cocci, 22%; and Candida species 5%. Inappropriate empirical antibiotic treatment (IEAT) was administered in 17.5% of septic shock episodes. Empirical β-lactam combined with other active antibiotics was associated with the lowest mortality observed. When amikacin was the only active antibiotic, mortality was 90%. Addition of empirical specific gram-positive coverage had no impact on mortality. Mortality was higher when IEAT was administered (76% vs 51%, p=0.002). Age >70 years (OR 2.3, 95% CI 1.2-4.7), IEAT for Candida spp. or gram-negative bacilli (OR 3.8, 1.3-11.1), acute kidney injury (OR 2.6, 1.4-4.9) and amikacin as the only active antibiotic (OR 15.2, 1.7-134.5) were independent risk factors for mortality, while combination of β-lactam and amikacin was protective (OR 0.32, 0.18-0.57). Conclusions: Septic shock in febrile neutropenic patients with BSI is associated with extremely high mortality, especially when IEAT is administered. Combination therapy including an active β-lactam and amikacin results in the best outcomes.

Risk Factors of Death in Bloodstream Infections Caused by AmpC β-Lactamase-Producing Enterobacterales in Patients with Neoplasia

Purpose

The infections caused by ESCPM Enterobacterales (Enterobacter spp., Serratia spp., Citrobacter spp., Providencia spp. and Morganella spp.) have limited therapeutic options. Patients with neoplastic diseases are particularly vulnerable to bloodstream infections (BSIs).

Objective

To analyze determinant factors of death in patients with neoplasia complicated with BSI caused by ESCPM Enterobacterales.

Patients and Methods

A cohort study of patients aged 18 years or older with neoplasia and BSI due to ESCPM group was conducted at the Cancer Hospital I of the National Cancer Institute, Brazil, from September 2012 to December 2017. The variables associated with death were analyzed using multivariate logistic regression.

Results

Of the 103 patients included in the cohort, 67.0% were male, the median age was 63 years and 67.0% had solid tumors. Of the 107 BSI episodes evaluated, 70.1% were hospital-acquired infections, 54.2% were secondary to extravascular focus of infection, gastrointestinal tract (19.6%), mainly. Enterobacter spp. (n: 49, 45.4%) was the most frequent agent isolated followed by Serratia spp. (n: 34, 31.5%), Morganella morganii (n: 16, 14.9%), Citrobacter freundii. (n: 7, 6.5%) and Providencia spp. (n: 2, 1.8%). Ten (9.3%) BSI episodes were caused by multidrug-resistant ESCPM Enterobacterales (MDR-ESCPM). The 7-day and 30-day mortality were 9.3% and 21.5%, respectively. The BSIs caused by MDR-ESCPM were independently associated with 7-day death (OR = 21.62 95% CI: 1.81–258.51 P = 0.01). Monotherapy with piperacillin-tazobactam tended to be associated with 7-day death (OR = 10.46 95% CI: 0.97–112.91 P = 0.05) and 30-day death (OR = 2.73 95% CI: 0.96–7.70 P = 0.05).

Conclusion

BSIs due to ESCPM group have high mortality and when caused by MDR-ESCPM are independently associated with 7-day death. The possible association of piperacillin-tazobactam monotherapy for BSI-ESCPM with death needs to be better studied.

Multidrug-resistant, gram-negative infections in high-risk haematologic patients: an update on epidemiology, diagnosis and treatment

PURPOSE OF REVIEW

Multidrug-resistant Gram-negative bacilli (MDR-GNB) infections are a significant cause of morbidity and mortality in high-risk hematologic patients. Early diagnosis and management of antibiotic treatment in these patients is a challenge for physicians. This review focuses on the latest literature reports that concern the epidemiology, diagnosis and treatment of MDR-GNB infections in this population.

RECENT FINDINGS

High-risk haematological patients have several risk factors that make them particularly susceptible to MDR-GNB infections. Few studies have examined the implementation of rapid diagnostic methods for multidrug resistance, and their impact on management in this population. Inappropriate empiric antibiotic treatment in these patients has been described frequently and is associated with poor outcomes.

SUMMARY

Knowledge of the local epidemiology of MDR-GNB is a basic requirement to guide empiric antibiotic treatments in each centre. New diagnosic tests might help in faster identification of MDR-GNB infections. Appropriate empiric antibiotic treatment is crucial for improving patients' prognosis. Important strategies to reduce inadequate antibiotic treatment include better risk stratification for MDR-GNB infection and the introduction of new, more broad-spectrum antibiotic therapies.

Clinical prediction of bacteremia and early antibiotics therapy in patients with solid tumors

OBJECTIVE

To investigate the relationship between the systemic inflammatory response syndrome (SIRS), early antibiotic use, and bacteremia in solid-tumor patients.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a retrospective observational study of adults with solid tumors admitted to a tertiary-care hospital through the emergency department over a 2-year period. Patients with neutropenic fever, organ transplant, trauma, or cardiopulmonary arrest were excluded.

METHODS

Rates of SIRS, bacteremia, and early antibiotics (initiation within 8 hours of presentation) were compared using the χ2 and Student t tests. Binomial regression and receiver operator curves were analyzed to assess predictors of bacteremia and early antibiotics.

RESULTS

Early antibiotics were administered in 507 (37%) of 1,344 SIRS-positive cases and 492 (22%) of 2,236 SIRS-negative cases (P < .0001). Of SIRS-positive cases, 70% had blood cultures drawn within 48 hours and 19% were positive; among SIRS negative cases, 35% had cultures and 13% were positive (19% vs 13%; P = .003). Bacteremic cases were more often SIRS positive than nonbacteremic cases (60% vs 50%; P =.003), but they received early antibiotics at similar rates (50% vs 49%, P = .72). Three SIRS components predicted early antibiotics: temperature (OR, 1.7; 95% CI, 1.31-2.29; P = .0001), tachycardia (OR, 1.4; 95% CI, 1.10-1.69; P < .0001), and white blood-cell count (OR, 1.8; 95% CI, 1.56-2.14; P < .0001). Only temperature (OR, 1.6; 95% CI, 1.09-2.41; P = .01) and tachycardia (OR, 1.5; 95% CI, 1.09-2.06; P = .01) predicted bacteremia. SIRS criteria as a composite were poorly predictive of bacteremia (AUC, 0.57).

CONCLUSIONS

SIRS criteria are frequently used to determine the need for early antibiotics, but they are poor predictors of bacteremia in solid-tumor patients. More reliable models are needed to guide judicious use of antibiotics in this population.

A TTP-incorporated scoring model for predicting mortality of solid tumor patients with bloodstream infection caused by Escherichia coli

Background

Few mortality-scoring models are available for solid tumor patients who are predisposed to develop Escherichia coli–caused bloodstream infection (ECBSI). We aimed to develop a mortality-scoring model by using information from blood culture time to positivity (TTP) and other clinical variables.

Methods

A cohort of solid tumor patients who were admitted to hospital with ECBSI and received empirical antimicrobial therapy was enrolled. Survivors and non-survivors were compared to identify the risk factors of in-hospital mortality. Univariable and multivariable regression analyses were adopted to identify the mortality-associated predictors. Risk scores were assigned by weighting the regression coefficients with corresponding natural logarithm of the odds ratio for each predictor.

Results

Solid tumor patients with ECBSI were distributed in the development and validation groups, respectively. Six mortality-associated predictors were identified and included in the scoring model: acute respiratory distress (ARDS), TTP ≤ 8 h, inappropriate antibiotic therapy, blood transfusion, fever ≥ 39 °C, and metastasis. Prognostic scores were categorized into three groups that predicted mortality: low risk (< 10% mortality, 0–1 points), medium risk (10–20% mortality, 2 points), and high risk (> 20% mortality, ≥ 3 points). The TTP-incorporated scoring model showed excellent discrimination and calibration for both groups, with AUC being 0.833 vs 0.844, respectively, and no significant difference in the Hosmer–Lemeshow test (6.709, P = 0.48) and the chi-square test (6.993, P = 0.46). Youden index showed the best cutoff value of ≥ 3 with 76.11% sensitivity and 79.29% specificity. TTP-incorporated scoring model had higher AUC than no TTP-incorporated model (0.837 vs 0.817, P < 0.01).

Conclusions

Our TTP-incorporated scoring model was associated with improving capability in predicting ECBSI-related mortality. It can be a practical tool for clinicians to identify and manage bacteremic solid tumor patients with high risk of mortality.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00520-021-06442-z.

Clinical Characteristics and Outcome of Bloodstream Infections in HIV-Infected Patients with Cancer and Febrile Neutropenia: A Case-Control Study

INTRODUCTION

We aimed to compare the clinical characteristics and outcomes of bloodstream infections (BSI) in cancer patients presenting febrile neutropenia with and without HIV infection, and analyze the prognostic factors for mortality.

METHODS

BSI episodes in febrile neutropenic patients following chemotherapy were prospectively collected (1997-2018). A case (HIV-infected)-control (non-HIV-infected) sub-analysis was performed (1:2 ratio), matching patients by age, gender, baseline disease, and etiological microorganism.

RESULTS

From 1755 BSI episodes in neutropenic cancer patients, 60 (3.4%) occurred in those with HIV. HIV characteristics: 51.7% were men who have sex with men; 58.3% had < 200 CD4; 51.7% had a detectable HIV-1 RNA viral load before the BSI episode; 70.0% met AIDS-defining criteria; and 93.3% were on antiretroviral therapy, with a protease inhibitor-based regimen being the most common (53.0%). HIV-infected patients were younger, more frequently male and more commonly presenting chronic liver disease (p < 0.001 for all). BSI due to Enterococcus spp. was significantly more frequent among patients with HIV (p = 0.017) with no differences in other pathogens. HIV-infected patients with cancer presented with shock more frequently (p = 0.014) and had higher mortality (31.7% vs. 18.1%, p = 0.008). In the case-control analysis, cases (HIV-infected) had chronic liver disease (p = 0.003) more frequently, whereas acute leukemia (p = 0.013) and hematopoietic stem-cell transplant (p = 0.023) were more common among controls. There was a non-significant trend for cases to have higher mortality (p = 0.084). However, in multivariate analysis, HIV infection was not associated with mortality (p = 0.196).

CONCLUSION

HIV-infected patients with cancer developing febrile neutropenia and BSI have different epidemiological and clinical profiles, and experience higher mortality. However, HIV infection by itself was not associated with mortality.

Antibiotic-Resistant Infections and Treatment Challenges in the Immunocompromised Host: An Update

This article reviews antibiotic resistance and treatment of bacterial infections in the growing number of patients who are immunocompromised: solid organ transplant recipients, the neutropenic host, and persons with human immunodeficiency virus and AIDS. Specific mechanisms of resistance in both gram-negative and gram-positive bacteria, as well as newer treatment options are addressed elsewhere and are only briefly discussed in the context of the immunocompromised host.

Stopping antibiotic therapy after 72 h in patients with febrile neutropenia following intensive chemotherapy for AML/MDS (safe study): A retrospective comparative cohort study

BACKGROUND

Induction chemotherapy for acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) is almost universally complicated by febrile neutropenia(FN). Empirical broad-spectrum antibiotic therapy (EBAT) strategies advocated by guidelines result in long periods of broad-spectrum antibiotic therapy. We compared the outcome of AML/MDS patients treated with a 3-day versus a prolonged (until neutrophil recovery) regimen.

METHODS

This is a retrospective comparative cohort study in AML or MDS patients undergoing remission-induction chemotherapy from 2011 to 2019, comparing 2 tertiary care hospitals with different strategies regarding antibiotic treatment for FN. At Erasmus University medical center(EMC), EBAT was stopped after 3 days of FN, in absence of a clinically or microbiologically documented infection. In the University Hospitals Leuven(UZL), a prolonged strategy was used, where EBAT was given until neutrophil recovery. The primary endpoint was a serious medical complication(SMC) defined as death or ICU admission in the 30 days after the start of chemotherapy.

FINDINGS

305 and 270 AML or MDS patients received chemotherapy at EMC and UZL, respectively. Broad-spectrum antibiotic treatment was given for a median of 19 days (IQR13-25) at UZL versus 9 days at EMC (IQR5-13) (p <0·001). With the 3-day EBAT strategy, an SMC was observed in 12·5% versus 8·9% with the prolonged strategy (p = 0·17). The hazard ratio for an SMC was not significantly higher with the 3-day strategy (HR 1·357,95%CI 0·765-2·409).

INTERPRETATION

This study suggests that during remission induction chemotherapy it is safe to stop antibiotics after 3 days of FN in absence of infection. A comparison of both strategies in a prospective trial should be pursued.

Machine Learning to Assess the Risk of Multidrug-Resistant Gram-Negative Bacilli Infections in Febrile Neutropenic Hematological Patients

INTRODUCTION

We aimed to assess risk factors for multidrug-resistant Gram-negative bacilli (MDR-GNB) from a large amount of data retrieved from electronic health records (EHRs) and determine whether machine learning (ML) may be useful in assessing the risk of MDR-GNB infection at febrile neutropenia (FN) onset.

METHODS

Retrospective study of almost 7 million pieces of structured data from all consecutive episodes of FN in hematological patients in a tertiary hospital in Barcelona (January 2008-December 2017). Conventional multivariate analysis and ML algorithms (random forest, gradient boosting machine, XGBoost, and GLM) were done.

RESULTS

A total of 3235 episodes of FN in 349 patients were documented; MDR-GNB caused 180 (5.6%) infections in 132 patients. The most frequent MDR-GNBs were MDR-Pseudomonas aeruginosa (53%) and extended-spectrum beta-lactamase-producing Enterobacterales (46%). According to conventional logistic regression analysis, independent factors associated with MDR-GNB infection were age older than 45 years (OR 2.07; 95% CI 1.31-3.24), prior antibiotics (2.62; 1.39-4.92), first-ever FN in this hospitalization (2.94; 1.33-6.52), prior hospitalizations for FN (1.72; 1.02-2.89); at least 15 prior hospital visits (2.65; 1.31-5.33), high-risk hematological diseases (3.62; 1.12-11.67), and hospitalization in a room formerly occupied by patients with MDR-GNB isolation (1.69; 1.20-2.38). ML algorithms achieved the following AUC and F1 score for MDR-GNB prediction: random forest, 0.79-0.9711; GMB, 0.79-0.9705; XGBoost, 0.79-0.9670; and GLM, 0.78-0.9716.

CONCLUSION

Data generated in EHRs proved useful in assessing risk factors for MDR-GNB infections in patients with FN. The great number of analyzed variables allowed us to identify new factors related to MDR infection, as well as to train ML algorithms for infection predictions. This information may be used by clinicians to make better clinical decisions.

Is it time to reconsider prophylactic antimicrobial use for hematopoietic stem cell transplantation? a narrative review of antimicrobials in stem cell transplantation

INTRODUCTION

Hematopoietic Stem Cell Transplantation (HSCT) is a life-saving procedure for multiple types of hematological cancer, autoimmune diseases, and genetic-linked metabolic diseases in humans. Recipients of HSCT transplant are at high risk of microbial infections that significantly correlate with the presence of graft-versus-host disease (GVHD) and the degree of immunosuppression. Infection in HSCT patients is a leading cause of life-threatening complications and mortality.

AREAS COVERED

This review covers issues pertinent to infection in the HSCT patient, including bacterial and viral infection; strategies to reduce GVHD; infection patterns; resistance and treatment options; adverse drug reactions to antimicrobials, problems of antimicrobial resistance; perturbation of the microbiome; the role of prebiotics, probiotics, and antimicrobial peptides. We highlight potential strategies to minimize the use of antimicrobials.

EXPERT OPINION

Measures to control infection and its transmission remain significant HSCT management policy and planning issues. Transplant centers need to consider carefully prophylactic use of antimicrobials for neutropenic patients. The judicious use of appropriate antimicrobials remains a crucial part of the treatment protocol. However, antimicrobials' adverse effects cause microbiome diversity and dysbiosis and have been shown to increase morbidity and mortality.

Understanding and Managing Sepsis in Patients With Cancer in the Era of Antimicrobial Resistance

Sepsis is a frequent complication in immunosuppressed cancer patients and hematopoietic stem cell transplant recipients that is associated with high morbidity and mortality rates. The worldwide emergence of antimicrobial resistance is of special concern in this population because any delay in starting adequate empirical antibiotic therapy can lead to poor outcomes. In this review, we aim to address: (1) the mechanisms involved in the development of sepsis and septic shock in these patients; (2) the risk factors associated with a worse prognosis; (3) the impact of adequate initial empirical antibiotic therapy given the current era of widespread antimicrobial resistance; and (4) the optimal management of sepsis, including adequate and early source control of infection, optimized antibiotic use based on the pharmacokinetic and pharmacodynamics changes in these patients, and the role of the new available antibiotics.

8th European Conference on Infections in Leukaemia: 2020 guidelines for the use of antibiotics in paediatric patients with cancer or post-haematopoietic cell transplantation

Paediatric patients with cancer and those undergoing haematopoietic cell transplantation are at high risk of bacterial infections. The 8th European Conference on Infections in Leukaemia (ECIL-8) convened a Paediatric Group to review the literature and to formulate recommendations for the use of antibiotics according to the European Society of Clinical Microbiology and Infectious Diseases grading system. The evaluation of antibacterial prophylaxis included mortality, bloodstream infection, febrile neutropenia, emergence of resistance, and adverse effects as endpoints. Initial antibacterial therapy and antibiotic de-escalation or discontinuation focused on patients with a clinically stable condition and without previous infection or colonisation by resistant bacteria, and on patients with a clinically unstable condition or with previous infection or colonisation by resistant bacteria. The final considerations and recommendations of the ECIL-8 Paediatric Group on antibacterial prophylaxis, initial therapy, and de-escalation strategies are summarised in this Policy Review.

Investigation of Gram-Negative Bacilli Bacteraemia in a Tertiary Hospital in Nigeria: Epidemiology and Antimicrobial Susceptibility Pattern

Background: The re-emergence of gram-negative bacilli (GNB) as the predominant cause of bacteraemia remains a major concern, given the increasing trend of antimicrobial resistance among this group of organisms. Prompt and effective empirical antibiotic treatment is vital for preventing adverse outcomes; therefore, a good knowledge of the local bacteria profile is required. Objective: This study was designed to aid the establishment of local antibiogram and empirical treatment for GNB bacteremia in patients referred to the University of Port Harcourt Teaching Hospital (UPTH), Nigeria. Materials and Methods: A total of 230 blood samples were obtained from inpatients in different units/departments from December 2017 to November 2018. The blood cultures were processed using BACTEC 9060 automated blood culture system, and the isolates were identified using MICROBACT 12E identification kits (Oxoid, UK) at the microbiology laboratory of UPTH. Susceptibility and resistance tests were done according to CLSI guidelines. Relevant information was obtained from the laboratory request forms and patients’ clinical files. Results: The prevalence of GNB in the study was 28.9% (71/246). The distribution of GNB bacteraemia was as follows: surgical unit (26.8%), special care baby unit (SCBU) (23.9%), intensive care unit (ICU) (21.1%), and paediatric ward (8.5%). The most common source of bacteraemia was pneumonia (35.2%) followed by puerperal sepsis (15.1%) and urinary tract infection (UTI) (15.1%). Klebsiella pneumoniae was the most frequently isolated gram-negative bacillus (26.6%). The overall resistance rate of extended spectrum lactamase producing Enterobacteriaceae (ESBL) producers, carbapenemase producers, and multi-drug resistant (MDR) organisms was 32.4%, with Acinetobacter baumannii (50%) and Pseudomonas aeruginosa (27.3%) exhibiting the highest level of resistance to carbapenems. Conclusion: This study showed a high MDR rate among GNB causing bacteraemia in patients at UPTH. An urgent review of the current antimicrobial prescription policy and infection control measures is recommended.

Multidrug-Resistant Infections and Outcome of Critically Ill Patients with Coronavirus Disease 2019: A Single Center Experience

Background: The aim of this study was to assess the drivers of multidrug-resistant (MDR) bacterial infection development in coronavirus disease 2019 (COVID-19) and its impact on patient outcome. Methods: Retrospective analysis on data from 32 consecutive patients with COVID-19, admitted to our intensive care unit (ICU) from March to May 2020. Outcomes considered were MDR infection and ICU mortality. Results: Fifty percent of patients developed an MDR infection during ICU stay after a median time of 8 [4-11] days. Most common MDR pathogens were carbapenem-resistant Klebsiella pneumoniae and Acinetobacter baumannii, causing bloodstream infections and pneumonia. MDR infections were linked to a higher length of ICU stay (p = 0.002), steroid therapy (p = 0.011), and associated with a lower ICU mortality (odds ratio: 0.439, 95% confidence interval: 0.251-0.763; p < 0.001). Low-dose aspirin intake was associated with both MDR infection (p = 0.043) and survival (p = 0.015). Among MDR patients, mortality was related with piperacillin-tazobactam use (p = 0.035) and an earlier onset of MDR infection (p = 0.042). Conclusions: MDR infections were a common complication in critically ill COVID-19 patients at our center. MDR risk was higher among those dwelling longer in the ICU and receiving steroids. However, MDR infections were not associated with a worse outcome.

Long-Term Impact of an Educational Antimicrobial Stewardship Program on Management of Patients with Hematological Diseases

Antimicrobial stewardship programs (ASPs) in hematological patients are especially relevant. However, information about ASPs in this population is scarce. For 11 years, we quarterly assessed antimicrobial consumption and incidence and death rates of multidrug-resistant (MDR) bloodstream infections (BSI) in the hematology Department. Healthcare activity indicators were also monitored yearly. We performed an interrupted time-series analysis. Antimicrobials showed a sustained reduction with a relative effect of −62.3% (95% CI −84.5 to −40.1) nine years after the inception of the ASP, being especially relevant for antifungals (relative effect −80.4%, −90.9 to −69.9), quinolones (relative effect −85.0%, −102.0 to −68.1), and carbapenems (relative effect −68.8%, −126.0 to −10.6). Incidence density of MDR BSI remained low and stable (mean 1.10 vs. 0.82 episodes per 1000 occupied bed days for the pre-intervention and the ASP period, respectively) with a quarterly percentage of change of −0.3% (95% CI −2.0 to 1.4). Early and late mortality of MDR BSI presented a steady trend (quarterly percentage of change −0.7%, 95% CI −1.7 to 0.3 and −0.6%, 95% CI −1.5 to 0.3, respectively). Volume and complexity of healthcare activity increased over the years. The ASP effectively achieved long-term reductions in antimicrobial consumption and improvements in the prescription profile, without increasing the mortality of MDR BSI.

Infectious Complications in Paediatric Haematopoetic Cell Transplantation for Acute Lymphoblastic Leukemia: Current Status

Haematopoietic stem cell transplantation (HSCT) in paediatric patients with acute lymphoblastic leukaemia (ALL) is associated with a variety of infectious complications which result in significant morbidity and mortality. These patients are profoundly immunocompromised, and immune reconstitution after HSCT generally occurs in astrictly defined order. During the early phase after HSCT until engraftment, patients are at risk of infections due to presence of neutropenia and mucosal damage, with Gramme-positive and Gramme-negative bacteria and fungi being the predominant pathogens. After neutrophil recovery, the profound impairment of cell-mediated immunity and use of glucocorticosteroids for control of graft-vs.-host disease (GvHD) increases the risk of invasive mould infection and infection or reactivation of various viruses, such as cytomegalovirus, varicella zoster virus, Epstein-Barr virus and human adenovirus. In the late phase, characterised by impaired cellular and humoral immunity, particularly in conjunction with chronic GvHD, invasive infections with encapsulated bacterial infections are observed in addition to fungal and viral infections. HSCT also causes a loss of pretransplant naturally acquired and vaccine-acquired immunity; therefore, complete reimmunization is necessary to maintain long-term health in these patients. During the last two decades, major advances have been made in our understanding of and in the control of infectious complications associated with HSCT. In this article, we review current recommendations for the diagnosis, prophylaxis and treatment of infectious complications following HSCT for ALL in childhood.

Defining the needs of patients with recurrent and/or metastatic head and neck cancer: An expert opinion

The clinical and biological heterogeneity of head and neck cancer (HNC) is paralleled by a plethora of different symptoms that affect the patient's quality of life. These symptoms include, for instance, pain, fatigue, nutritional issues, airways obstruction, voice alterations and psychological distress. In addition, patients with HNC are prone to a high risk of infection, and may also suffer from acute complications, such as hypercalcemia, spine compression by bone metastasis or bleeding. Prolonging survival is also an inherent expectation for all patients. Addressing the above needs is crucial in all patients with HNC, and especially in those with recurrent and/or metastatic (RM) disease. However, research on how to address patients' needs in RM-HNC remains scarce. This paper defines patients' needs for RM HNC and presents an Expert Opinion on how to address them, proposing also some lines of research.

Cefepime Versus Cefepime Plus Amikacin as an Initial Antibiotic Choice for Pediatric Cancer Patients With Febrile Neutropenia in an Era of Increasing Cefepime Resistance

BACKGROUND

We investigated the treatment outcomes before and after the addition of amikacin to cefepime monotherapy as an initial empirical antibiotic treatment in pediatric cancer patients with febrile neutropenia.

METHODS

This was a retrospective historical cohort study. The subjects were pediatric cancer patients who visited the emergency room at the Samsung Medical Center, Seoul, Korea, due to chemotherapy-induced febrile neutropenia, between January 2011 and December 2016. Since September 2014, the empirical antimicrobial treatment regimen for febrile neutropenia was changed from high-dose cefepime monotherapy to combination therapy of adding a single dose of amikacin.

RESULTS

Two hundred twenty-five bacteremia episodes in 164 patients were reported during the study period. Bacteremia caused by cefepime-resistant Gram-negative bacteria was observed in 16% of patients before September 2014 and in 21% of the patients after September 2014 (P = 0.331). Use of appropriate empirical antibiotic treatments increased from 62% to 83% following addition of amikacin to cefepime treatment (P = 0.003). The duration of fever was shorter in the cefepime plus amikacin group than in the cefepime group (22 vs. 34 hours, P = 0.014); however, rates of septic shock and pediatric intensive care unit hospitalizations were not significantly different between the 2 groups (septic shock, both 7%, P = 0.436; pediatric intensive care unit 3% vs. 1%, P = 0.647).

CONCLUSIONS

We observed no additional benefit of amikacin addition to high-dose cefepime monotherapy. Therefore, adding amikacin to cefepime monotherapy in conditions where cefepime-resistant Gram-negative bacteremia amounts to 20% or less may not be justified.