Fluoroquinolones, antimicrobial resistance and neutropenic cancer patients:

Levofloxacin prophylaxis for pediatric leukemia patients: monitoring of outcomes for sustained benefit and consequences

Levofloxacin prophylaxis reduces bloodstream infections in neutropenic patients with acute myeloid leukemia or relapsed acute lymphoblastic leukemia. A retrospective, longitudinal cohort study compares incidence of bacteremia, multidrug-resistant organisms (MDRO), and Clostridioides difficile (CDI) between time periods of levofloxacin prophylaxis implementation. Benefits were sustained without increasing MDRO or CDI.

Efficacy of prophylactic antibiotics for the prevention of neutropenic fever in patients with multiple myeloma receiving high-dose cyclophosphamide for stem cell mobilization

High-dose cyclophosphamide (HD-Cy) (3 g/m2) plus granulocyte colony-stimulating factor (G-CSF) is a very effective regimen for peripheral blood stem cell (PBSC) mobilization. Unfortunately, it is associated with an increased risk of neutropenic fever (NF). We analyzed the effect of NF on PBSC apheresis results and the efficacy of prophylactic antibiotics for the prevention of NF associated with HD-Cy plus G-CSF for PBSC mobilization in patients with newly diagnosed multiple myeloma (MM). First, patients were divided into NF ( +) and NF ( -) groups according to whether they suffered from NF during mobilization. Second, we divided patients into an antibiotic prophylaxis group and a nonantibiotic prophylaxis group according to whether antibiotic prophylaxis was used during the mobilization period. Our study showed that NF( +) patients (n = 44) had lower CD34 + cell dose collection (median 2.60 versus 5.34 × 106/kg, P < 0.001) and slower neutrophil engraftment and platelet engraftment (median 11 versus 10 days, P = 0.002, and median 13 versus 11 days, P = 0.043, respectively) than NF( -) patients (n = 234). Of note, the nonantibiotic prophylaxis group patients (n = 30) had a 26.7% incidence of NF. In the patients receiving antibiotic prophylaxis (n = 227), the incidence was reduced to 9.3% (P = 0.01). The antibiotic prophylaxis patients had higher CD34 + cell collection (median 5.41 versus 2.27 × 106/kg, P < 0.001) and lower hospitalization cost of mobilization ($ median 3108.02 versus 3702.39, p = 0.012). Thus, our results demonstrate that NF is associated with lower CD34 + cell collection and that antibiotic prophylaxis can reduce the incidence of NF and improve stem cell mobilization and collection outcomes, which reduces the hospitalization cost of mobilization.

ICU-acquired infections in immunocompromised patients

Immunocompromised patients account for an increasing proportion of the typical intensive care unit (ICU) case-mix. Because of the increased availability of new drugs for cancer and auto-immune diseases, and improvement in the care of the most severely immunocompromised ICU patients (including those with hematologic malignancies), critically ill immunocompromised patients form a highly heterogeneous patient population. Furthermore, a large number of ICU patients with no apparent immunosuppression also harbor underlying conditions altering their immune response, or develop ICU-acquired immune deficiencies as a result of sepsis, trauma or major surgery. While infections are associated with significant morbidity and mortality in immunocompromised critically ill patients, little specific data are available on the incidence, microbiology, management and outcomes of ICU-acquired infections in this population. As a result, immunocompromised patients are usually excluded from trials and guidelines on the management of ICU-acquired infections. The most common ICU-acquired infections in immunocompromised patients are ventilator-associated lower respiratory tract infections (which include ventilator-associated pneumonia and tracheobronchitis) and bloodstream infections. Recently, several large observational studies have shed light on some of the epidemiological specificities of these infections-as well as on the dynamics of colonization and infection with multidrug-resistant bacteria-in these patients, and these will be discussed in this review. Immunocompromised patients are also at higher risk than non-immunocompromised hosts of fungal and viral infections, and the diagnostic and therapeutic management of these infections will be covered. Finally, we will suggest some important areas of future investigation.

High pretreatment disease burden as a risk factor for infectious complications following CD19 chimeric antigen receptor T-cell therapy for large B-cell lymphoma

Infection has emerged as the chief cause of non-relapse mortality (NRM) post CD19-targeting chimeric antigen receptor T-cell therapy (CAR-T) therapy. Even though up to 50% of patients may remain infection-free, many suffer multiple severe, life-threatening, or fatal infectious events. The primary aim of this study was to explore severe and life-threatening infections post licensed CAR-T therapy in large B-cell lymphoma, with a focus on the role of disease burden and disease sites in assessing individual risk. We sought to understand the cohort of patients who experience ≥2 infections and those at the highest risk of infectious NRM. Our analysis identifies a higher disease burden after bridging therapy as associated with infection events. Those developing ≥2 infections emerged as a uniquely high-risk cohort, particularly if the second (or beyond) infection occurred during an episode of immune effector cell-associated neurotoxicity syndrome (ICANS) or while on steroids and/or anakinra for ICANS. Herein, we also describe the first reported cases of "CAR-T cold sepsis," a phenomenon characterized by the lack of an appreciable systemic inflammatory response at the time of detection of infection. We propose a risk-based strategy to encourage heightened clinician awareness of cold sepsis, with a view to reducing NRM.

Prevalence of Pseudomonas aeruginosa and its antibiotic resistance in patients who have received Hematopoietic Stem-Cell Transplantation; A globally Systematic Review

Gram-negative bacteria are infectious and life-threatening agents after hematopoietic stem cell transplantation (HSCT). So, this study aimed to investigate the prevalence of Pseudomonas aeruginosa and its antibiotic resistance in patients who have received Hematopoietic Stem-Cell Transplantation through a systematic review. The systematic search was done with key words; Pseudomonas aeruginosa, hematopoietic stem cell transplantation from 2000 to the end of July 2023 in Google Scholar and PubMed/Medline, Scopus, and Web of Science. Twelve studies were able to include our study. Quality assessment of studies was done by Appraisal tool for Cross-Sectional Studies. The most of the included studies were conducted as allo-HSCT. Infections such as respiratory infection, urinary infection and bacteremia have occurred. The rate of prevalence with P. aeruginosa has varied between 3 and 100%. The average age of the participants was between 1 and 74 years. The rate of prevalence of P. aeruginosa resistant to several drugs has been reported to be variable, ranging from 20 to 100%. The highest antibiotic resistance was reported against cefotetan (100%), and the lowest was related to tobramycin (1.8%) followed by amikacin, levofloxacin and ciprofloxacin with the prevalence of 16.6%. Our findings showed a high prevalence and antibiotic resistance rate of P. aeruginosa in Hematopoietic stem cell transplantation. Therefore, more serious health measures should be taken in patients after transplantation.

Immune effector cell-associated hematotoxicity: EHA/EBMT consensus grading and best practice recommendations

Hematological toxicity is the most common adverse event after chimeric antigen receptor (CAR) T-cell therapy. Cytopenias can be profound and long-lasting and can predispose for severe infectious complications. In a recent worldwide survey, we demonstrated that there remains considerable heterogeneity in regard to current practice patterns. Here, we sought to build consensus on the grading and management of immune effector cell-associated hematotoxicity (ICAHT) after CAR T-cell therapy. For this purpose, a joint effort between the European Society for Blood and Marrow Transplantation (EBMT) and the European Hematology Association (EHA) involved an international panel of 36 CAR T-cell experts who met in a series of virtual conferences, culminating in a 2-day meeting in Lille, France. On the basis of these deliberations, best practice recommendations were developed. For the grading of ICAHT, a classification system based on depth and duration of neutropenia was developed for early (day 0-30) and late (after day +30) cytopenia. Detailed recommendations on risk factors, available preinfusion scoring systems (eg, CAR-HEMATOTOX score), and diagnostic workup are provided. A further section focuses on identifying hemophagocytosis in the context of severe hematotoxicity. Finally, we review current evidence and provide consensus recommendations for the management of ICAHT, including growth factor support, anti-infectious prophylaxis, transfusions, autologous hematopoietic stem cell boost, and allogeneic hematopoietic cell transplantation. In conclusion, we propose ICAHT as a novel toxicity category after immune effector cell therapy, provide a framework for its grading, review literature on risk factors, and outline expert recommendations for the diagnostic workup and short- and long-term management.

Identifying Early Infections in the Setting of CRS With Routine and Exploratory Serum Proteomics and the HT10 Score Following CD19 CAR-T for Relapsed/Refractory B-NHL

Early fever after chimeric antigen receptor T-cell (CAR-T) therapy can reflect both an infection or cytokine release syndrome (CRS). Identifying early infections in the setting of CRS and neutropenia represents an unresolved clinical challenge. In this retrospective observational analysis, early fever events (day 0-30) were characterized as infection versus CRS in 62 patients treated with standard-of-care CD19.CAR-T for relapsed/refractory B-cell non-Hodgkin lymphoma. Routine serum inflammatory markers (C-reactive protein [CRP], interleukin-6 [IL-6], procalcitonin [PCT]) were recorded daily. Exploratory plasma proteomics were performed longitudinally in 52 patients using a multiplex proximity extension assay (Olink proteomics). Compared with the CRS^only cohort, we noted increased event-day IL-6 (median 2243 versus 64 pg/mL, P = 0.03) and particularly high PCT levels (median 1.6 versus 0.3 µg/L, P < 0.0001) in the patients that developed severe infections. For PCT, an optimal discriminatory threshold of 1.5 µg/L was established (area under the receiver operating characteristic curve [AUC_ROC] = 0.78). Next, we incorporated day-of-fever PCT levels with the patient-individual CAR-HEMATOTOX score. In a multicenter validation cohort (n = 125), we confirmed the discriminatory capacity of this so-called HT10 score for early infections at first fever (AUC_ROC = 0.87, P < 0.0001, sens. 86%, spec. 86%). Additionally, Olink proteomics revealed pronounced immune dysregulation and endothelial dysfunction in patients with severe infections as evidenced by an increased ANGPT2/1 ratio and an altered CD40/CD40L-axis. In conclusion, the high discriminatory capacity of the HT10 score for infections highlights the advantage of dynamic risk assessment and supports the incorporation of PCT into routine inflammatory panels. Candidate markers from Olink proteomics may further refine risk-stratification. If validated prospectively, the score will enable risk-adapted decisions on antibiotic use.

Epidemiology and source of infection in cancer patients with febrile neutropenia: an experience from a developing country

BACKGROUND

Febrile neutropenia (FN) is a life-threatening complication that predisposes cancer patients to serious infections. This study aims to describe the epidemiology and source of infection in cancer patients with FN in a tertiary care hospital.

METHODS

A hospital-based retrospective study was conducted in a large tertiary care hospital from January 2020 to December 2021. Data on cancer patients with FN were collected from the hospital information system.

RESULTS

150 cancer patients with FN were identified during the study period. Most patients were males (98; 65.3%), and the mean age of participants was 42.2 ± 16.0 years. Most patients (127; 84.7%) had hematologic malignancies, and acute myeloid leukemia was the most common diagnosis (42; 28%), followed by acute lymphocytic leukemia (28; 18.7%) and Hodgkin's lymphoma (20; 13.3%). Fifty-four (36%) patients had a median Multinational Association for Supportive Care in Cancer (MASCC) scores greater than 21. Regarding the outcome, nine (6%) died, and 141(94%) were discharged. The focus of fever was unknown in most patients (108; 72%). Among the known origins of fever were colitis (12; 8%), pneumonia (8; 5.3%), cellulitis (6; 4%), bloodstream infections (7; 4.6%), perianal abscess (2; 1.3%) and others. The median duration of fever was two days, and the median duration of neutropenia was seven days. Sixty-three (42%) patients had infections: 56 (73.3%) were bacterial, four (2.6%) were viral, two (1%) were fungal and 1 (0.7%) was parasitic. Among the bacterial causes, 50 cases (89.2%) were culture-positive. Among the culture-positive cases, 34 (68%) were gram-positive and 22 (44%) were gram-negative. The most frequent gram-positive bacteria were E. faecalis (9; 18% of culture-positive cases), and the most frequent gram-negative organisms were Klebsiella pneumoniae (5; 10%). Levofloxacin was the most commonly used prophylactic antibiotic (23; 15.33%), followed by acyclovir (1610.7%) and fluconazole in 15 patients (10%). Amikacin was the most popular empiric therapy, followed by piperacillin/tazobactam (74; 49.3%), ceftazidime (70; 46.7%), and vancomycin (63; 42%). One-third of E. faecalis isolates were resistant to ampicillin. Approximately two-thirds of Klebsiella pneumoniae isolates were resistant to piperacillin/tazobactam and ceftazidime. Amikacin resistance was proven in 20% of isolates.

CONCLUSIONS

The majority of patients suffered from hematologic malignancies. Less than half of the patients had infections, and the majority were bacterial. Gram-positive bacteria comprised two-thirds of cases. Therefore, empiric therapy was appropriate and in accordance with the antibiogram of the isolated bacteria.

Long-Term Dominance of Carbapenem-Non-Susceptible Pseudomonas aeruginosa ST111 in Hematologic Malignancy Patients and Hematopoietic Cell Transplant Recipients

An epidemiological study uncovered that fluoroquinolone (FQ) neutropenic prophylaxis in hematopoietic cell transplant and hematologic malignancy (HCT/HM) patients was associated with breakthrough Pseudomonas aeruginosa bloodstream infections (BSIs) with isolates non-susceptible to both FQs and meropenem. The molecular epidemiology of the FQ/meropenem-non-susceptible P. aeruginosa isolates causing FQ-breakthrough BSIs in the HCT/HM patients remains unclear. Through whole genome sequencing on 57 P. aeruginosa isolates from 54 patients diagnosed with HM or receiving an HCT, we found that ST111 strains predominated, accounting for 22 (38.6%) of the isolates. 17 of 33 (51.5%) FQ-breakthrough BSIs were caused by ST111 strains, of which 15 (88.2%) were meropenem non-susceptible. ST111 strains, but not other oprD-deficient, meropenem-non-susceptible clinical strains, were found to have a colonization advantage over P. aeruginosa strain PA14 in C. elegans and to outcompete PA14 in in vitro co-culture assays. Together, we found that breakthrough P. aeruginosa BSIs during FQ prophylaxis in HCT/HM patients are dominated by clonally-related FQ/meropenem non-susceptible strains, predominantly ST111 type, and that the dominance of ST111 strains may be explained by a relative fitness advantage over other clinical strains. Additional work is necessary to better understand the factors driving the dominance and persistence of these ST111 strains.

Pseudomonas aeruginosa Infections in Cancer Patients

Pseudomonas aeruginosa (P. aeruginosa) is one of the most frequent opportunistic microorganisms causing infections in oncological patients, especially those with neutropenia. Through its ability to adapt to difficult environmental conditions and high intrinsic resistance to antibiotics, it successfully adapts and survives in the hospital environment, causing sporadic infections and outbreaks. It produces a variety of virulence factors that damage host cells, evade host immune responses, and permit colonization and infections of hospitalized patients, who usually develop blood stream, respiratory, urinary tract and skin infections. The wide intrinsic and the increasing acquired resistance of P. aeruginosa to antibiotics make the treatment of infections caused by this microorganism a growing challenge. Although novel antibiotics expand the arsenal of antipseudomonal drugs, they do not show activity against all strains, e.g., MBL (metalo-β-lactamase) producers. Moreover, resistance to novel antibiotics has already emerged. Consequently, preventive methods such as limiting the transmission of resistant strains, active surveillance screening for MDR (multidrug-resistant) strains colonization, microbiological diagnostics, antimicrobial stewardship and antibiotic prophylaxis are of particular importance in cancer patients. Unfortunately, surveillance screening in the case of P. aeruginosa is not highly effective, and a fluoroquinolone prophylaxis in the era of increasing resistance to antibiotics is controversial.

The CAR-HEMATOTOX risk-stratifies patients for severe infections and disease progression after CD19 CAR-T in R/R LBCL

Background

CD19-directed chimeric antigen receptor T-cell therapy (CAR-T) represents a promising treatment modality for an increasing number of B-cell malignancies. However, prolonged cytopenias and infections substantially contribute to the toxicity burden of CAR-T. The recently developed CAR-HEMATOTOX (HT) score—composed of five pre-lymphodepletion variables (eg, absolute neutrophil count, platelet count, hemoglobin, C-reactive protein, ferritin)—enables risk stratification of hematological toxicity.

Methods

In this multicenter retrospective analysis, we characterized early infection events (days 0–90) and clinical outcomes in 248 patients receiving standard-of-care CD19 CAR-T for relapsed/refractory large B-cell lymphoma. This included a derivation cohort (cohort A, 179 patients) and a second independent validation cohort (cohort B, 69 patients). Cumulative incidence curves were calculated for all-grade, grade ≥3, and specific infection subtypes. Clinical outcomes were studied via Kaplan-Meier estimates.

Results

In a multivariate analysis adjusted for other baseline features, the HT score identified patients at high risk for severe infections (adjusted HR 6.4, 95% CI 3.1 to 13.1). HT^high patients more frequently developed severe infections (40% vs 8%, p<0.0001)—particularly severe bacterial infections (27% vs 0.9%, p<0.0001). Additionally, multivariate analysis of post-CAR-T factors revealed that infection risk was increased by prolonged neutropenia (≥14 days) and corticosteroid use (≥9 days), and decreased with fluoroquinolone prophylaxis. Antibacterial prophylaxis significantly reduced the likelihood of severe bacterial infections in HT^high (16% vs 46%, p<0.001), but not HT^low patients (0% vs 2%, p=n.s.). Collectively, HT^high patients experienced worse median progression-free (3.4 vs 12.6 months) and overall survival (9.1 months vs not-reached), and were hospitalized longer (median 20 vs 16 days). Severe infections represented the most common cause of non-relapse mortality after CAR-T and were associated with poor survival outcomes. A trend toward increased non-relapse mortality in HT^high patients was observed (8.0% vs 3.7%, p=0.09).

Conclusions

These data demonstrate the utility of the HT score to risk-stratify patients for infectious complications and poor survival outcomes prior to CD19 CAR-T. High-risk patients likely benefit from anti-infective prophylaxis and should be closely monitored for potential infections and relapse.

Variation in Clinical Practice and Attitudes on Antibacterial Management of Fever and Neutropenia in Patients With Hematologic Malignancy: A Survey of Cancer Centers Across the United States

BACKGROUND

Contemporary information regarding fever and neutropenia (FN) management, including approaches to antibacterial prophylaxis, empiric therapy, and de-escalation across US cancer centers, is lacking.

METHODS

This was a self-administered, electronic, cross-sectional survey of antimicrobial stewardship physicians and pharmacists at US cancer centers. The survey ascertained institutional practices and individual attitudes on FN management in high-risk cancer patients. A 5-point Likert scale assessed individual attitudes.

RESULTS

Providers from 31 of 86 hospitals (36%) responded, and FN management guidelines existed in most (29/31, 94%) hospitals. Antibacterial prophylaxis was recommended in 27/31 (87%) hospitals, with levofloxacin as the preferred agent (23/27, 85%). Cefepime was the most recommended agent for empiric FN treatment (26/29, 90%). Most institutional guidelines (26/29, 90%) recommended against routine addition of empiric gram-positive agents except for specific scenarios. Eighteen of 29 (62%) hospitals explicitly provided guidance on de-escalation of empiric, systemic antibacterial therapy; however, timing of de-escalation was variable according to clinical scenario. Among 34 individual respondents, a majority agreed with use of antibiotic prophylaxis in high-risk patients (25, 74%). Interestingly, only 10 (29%) respondents indicated agreement with the statement that benefits of antibiotic prophylaxis outweigh potential harms.

CONCLUSION

Most US cancer centers surveyed had institutional FN management guidelines. Antibiotic de-escalation guidance was lacking in nearly 40% of centers, with heterogeneity in approaches when recommendations existed. Further research is needed to inform FN guidelines on antibacterial prophylaxis and therapy de-escalation.

Infections in Hospitalized Cancer Patients

Cancer patients are at an increased risk of developing infections that are primarily treatment-driven but may also be malignancy-driven. While cancer treatments such as chemotherapy, radiotherapy, and surgery have been known to improve malignancy morbidity and mortality, they also have the potential to weaken immune defenses and induce periods of severe cytopenia. These adverse effects pave the way for opportunistic infections to complicate a hospitalized cancer patient's clinical course. Understanding the risk each patient inherently has for developing a bacterial, fungal, or viral infection is critical to choosing the correct prophylactic treatment in conjunction with their scheduled cancer therapy. This review discusses the most common types of infections found in hospitalized cancer patients as well as the current guidelines for prophylactic and antimicrobial treatment in cancer patients. In addition, it describes the interaction between antibiotics and cancer therapies for consideration when treating infection in a cancer patient.

Bacteremia in Hematopoietic Stem Cell Recipients Receiving Fluoroquinolone Prophylaxis: Incidence, Resistance, and Risk Factors

Background

Bacteremia is a common complication in hematopoietic stem cell transplant (HSCT) recipients. Prophylactic fluoroquinolone is recommended and used in these individuals. Breakthrough infections can occur with fluoroquinolone-resistant strains. We aimed to identify the incidence, resistance, and risk factors for bacteremia in HSCT recipients receiving fluoroquinolone prophylaxis.

Materials and Methods

This retrospective study was performed on patients who received fluoroquinolone prophylaxis and underwent autologous and allogeneic HSCT between 2015 and 2019. The incidence of bacteremia, comorbidity, treatment, and invasive procedures was compared in these patients with and without bacteremia.

Results

There were 553 patients included in the study, 68 (12.3%) had bacteremia. The incidence of bacteremia is 8.2% of autologous HSCT recipients and 18.4% of allogeneic HSCT recipients. The significant risk factors associated with bacteremia were steroid-using (odds ratio [OR]:13.83, 95% confidence interval [CI]: 2.88 - 66.40), higher Charlson Comorbidity Index (CCI)-mean (OR: 1.57, 95% CI: 1.15 - 2.16), diabetes mellitus (OR: 4.29, 95% CI: 1.11 - 16.48) in autologous HSCT, steroid-using (OR: 6.84, 95% CI: 1.44 - 32.33), longer duration of neutropenia (OR: 1.05, 95% CI: 1.01 - 1.09) using central venous catheter (OR: 7.81, 95% CI: 1.00 - 61.23) in allogeneic HSCT. Seventy-three pathogens were isolated from a total of 68 bacteremia episodes. The most commonly occurring agents were Escherichia coli, Klebsiella pneumoniae and Enterococcus spp. Resistance to fluoroquinolones was 87.2%, 70.0% and 60.0% among these strains, respectively.

Conclusion

High CCI, diabetes mellitus, use of steroids and long-term neutropenia and use of central venous catheters were significantly associated with the breakthrough bacteremia in HSCT recipients receiving fluoroquinolone prophylaxis. Fluoroquinolone prophylaxis may reduce the incidence of bacteremia but may select strains resistant to fluoroquinolone.

A rapid evidence assessment exploring whether antimicrobial resistance complicates non-infectious health conditions and healthcare services, 2010-20

Antimicrobial resistance (AMR) is one of the greatest public health threats at this time. While there is a good understanding of the impacts of AMR on infectious diseases, an area of less focus is the effects AMR may be having on non-communicable health conditions (such as cancer) and healthcare services (such as surgery). Therefore, this study aimed to explore what impact AMR is currently having on non-communicable health conditions, or areas of health services, where AMR could be a complicating factor impacting on the ability to treat the condition and/or health outcomes. To do this, a rapid evidence assessment of the literature was conducted, involving a systematic approach to searching and reviewing the evidence. In total, 101 studies were reviewed covering surgery, organ transplants, cancer, ICUs, diabetes, paediatric patients, immunodeficiency conditions, liver and kidney disease, and physical trauma. The results showed limited research in this area and studies often use a selective population, making the results difficult to generalize. However, the evidence showed that for all health conditions and healthcare service areas reviewed, at least one study demonstrated a higher risk of death for patients with resistant infections, compared with no or drug-susceptible infections. Poor health outcomes were also associated with resistant infections in some instances, such as severe sepsis and failure of treatments, as well as a greater need for invasive medical support. While there are gaps in the evidence base requiring further research, efforts are also needed within policy and practice to better understand and overcome these challenges.

Bacterial bloodstream infections and patterns of resistance in patients with haematological malignancies at a tertiary centre in Lebanon over 10 years

OBJECTIVES

Bacterial bloodstream infections (BSIs) with resistant pathogens in patients with haematological malignancies are rising due to increased use of novel chemotherapeutic agents and prophylactic antibiotics. Our goal was to understand the epidemiology and resistance patterns of bacterial pathogens in patients with haematological malignancies to help tailor empirical antibiotics and to limit resistance.

METHODS

This was a retrospective chart review looking at bacterial BSI episodes between 2007-2017 in patients previously diagnosed with haematological malignancy at a tertiary-care centre in Lebanon.

RESULTS

Among 165 hospitalised patients with haematological malignancy and bacterial BSI over 10 years, Gram-negative bacteria (GNB) caused 65.0% of all episodes, with the most common pathogens being Escherichia coli (45.6%), 79.6% of which were ESBL-producers, Pseudomonas aeruginosa (7.5%) and Acinetobacter baumannii (4.0%). The majority of the organisms (61.0%) were multidrug-resistant (MDR), with ANC < 100 neutrophils/μL (OR = 0.12, 95% CI 0.03-0.54) identified as an independent marker for increased multidrug resistance. The risk factors associated with increased mortality included recent use of amikacin (p<0.001) and infections with organisms resistant to amikacin (p<0.001) or ciprofloxacin (p=0.04). Our results reflect a persistent pattern of Gram-negative predominance with E. coli remaining the most common isolated pathogen in bacterial BSIs in patients with haematological malignancies. The relative frequency of GNB to Gram-positive bacteria remains similar to our data from 2007.

CONCLUSION

The persistent divergence between worldwide data and the results observed in our centre and the increasing rates of MDR pathogens emphasise the importance of tailoring empirical antimicrobial therapy according to the centre's epidemiology.

Predictive and risk factor analysis for bloodstream infection in high-risk hematological patients with febrile neutropenia: post-hoc analysis from a prospective, large-scale clinical study

OBJECTIVES

Bloodstream infection (BSI) is a frequent complication observed in patients with febrile neutropenia (FN). BSI risk factors and incidence vary depending on chemotherapy types and prophylactic antimicrobial agents. We clarified these issues by post-hoc analysis of a prospective clinical trial cohort for severe FN in hematological malignancy.

METHODS

We performed an intention-to-treat analysis of 413 high-risk patients and 1272 blood culture sets.

RESULTS

Overall, 356 patients (86.2%) developed FN, and 20.8% had BSI complications. Prophylactic antimicrobials did not prevent complications of FN and BSI, but the incidence of BSIs of Gram-negative (GN) bacteria was lower than in the non-prophylaxis group (23.8% vs. 56.7%). Multinational Association of Supportive Care in Cancer (MASCC) scores < 20 were significantly correlated with the incidence of BSI, whereas MASCC scores > 21 were not (41.7% vs. 17.2%). The only significant risk factors were hypotension and dehydration. axillary temperatures were higher in GN-caused BSIs than in Gram-positive-caused BSIs and in patients with negative blood culture results (38.7 °C vs. 38.2 °C vs. 38.0 °C). The higher the fever, the higher the incidence of BSI and GN bacteremia.

CONCLUSIONS

MASCC score and axillary temperature are strong predictors of BSI. Non-administration of prophylactic antimicrobials and GN-caused BSI are correlated.

THE CLINICAL TRIAL REGISTRATION NUMBER

UMIN00010411.

Immune Reconstitution after Haploidentical Donor and Umbilical Cord Blood Allogeneic Hematopoietic Cell Transplantation

Allogeneic hematopoietic cell transplantation (HCT) is the only potentially curative therapy for a variety of hematologic diseases. However, this therapeutic platform is limited by an initial period when patients are profoundly immunocompromised. There is gradual immune recovery over time, that varies by transplant platform. Here, we review immune reconstitution after allogeneic HCT with a specific focus on two alternative donor platforms that have dramatically improved access to allogeneic HCT for patients who lack an HLA-matched related or unrelated donor: haploidentical and umbilical cord blood HCT. Despite challenges, interventions are available to mitigate the risks during the immunocompromised period including antimicrobial prophylaxis, modified immune suppression strategies, graft manipulation, and emerging adoptive cell therapies. Such interventions can improve the potential for long-term overall survival after allogeneic HCT.

Infectious complications in allogeneic hematopoietic cell transplant recipients: Review of transplant-related risk factors and current state of prophylaxis

Allogeneic hematopoietic cell transplantation is a complex procedure that carries a significant risk of complications. Infections are among the most common of them. Several direct factors such as neutropenia, hypogammaglobulinemia, lymphopenia, mucosal barrier injury, and graft-versus-host disease have been shown to be associated with increased infectious risk post-transplant. Apart from direct factors, there are also indirect transplant-related factors that are the primary trigger to the formers' development. The most important of them are type of preparative regimen, graft source, donor type, graft-versus-host disease prophylaxis, and graft manipulation techniques. In this review, an attempt has been made to summarize the role of the transplant-related factors in the development of infectious complications and provide evidence underlying the current concept of infectious disease prophylaxis in patients after allogeneic hematopoietic cell transplantation.

Prophylaxis, diagnosis and therapy of infections in patients undergoing high-dose chemotherapy and autologous haematopoietic stem cell transplantation. 2020 update of the recommendations of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

To ensure the safety of high-dose chemotherapy and autologous stem cell transplantation (HDC/ASCT), evidence-based recommendations on infectious complications after HDC/ASCT are given. This guideline not only focuses on patients with haematological malignancies but also addresses the specifics of HDC/ASCT patients with solid tumours or autoimmune disorders. In addition to HBV and HCV, HEV screening is nowadays mandatory prior to ASCT. For patients with HBs antigen and/or anti-HBc antibody positivity, HBV nucleic acid testing is strongly recommended for 6 months after HDC/ASCT or for the duration of a respective maintenance therapy. Prevention of VZV reactivation by vaccination is strongly recommended. Cotrimoxazole for the prevention of Pneumocystis jirovecii is supported. Invasive fungal diseases are less frequent after HDC/ASCT, therefore, primary systemic antifungal prophylaxis is not recommended. Data do not support a benefit of protective room ventilation e.g. HEPA filtration. Thus, AGIHO only supports this technique with marginal strength. Fluoroquinolone prophylaxis is recommended to prevent bacterial infections, although a survival advantage has not been demonstrated.

Bacterial Etiology of Wound Exudates in Tertiary Care Cancer Patients and Antibiogram of the Isolates

Introduction:

Patients with malignancies frequently develop infections as a result of surgical procedures and fungating wounds leading to pus formation. This cross-sectional study was conducted to explore the bacteriological spectra of infections of various cancer sites and their antibiotic sensitivity patterns among the patients visiting minor operation theatre (OT) of B.P. Koirala Memorial Cancer Hospital (BPKMCH), Chitwan, Nepal.

Methods:

Over a period of 3 months from September to November 2018, a total of 183 wound exudates and pus samples were collected and analyzed by standard microbiological procedures. Isolates were identified based on the colony characters, Gram staining and an array of biochemical tests. Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion technique according to criteria set by CLSI, 2016. Methicillin resistance in Staphylococcus aureus was tested with the help of cefoxitin using disc diffusion method.

Results:

Out of the 183 samples, 149 (81.4%) were culture positive. Among 13 different isolates identified, S. aureus (43.0%) was predominant followed by E. coli (14.0%). Higher incidence of bacteria was seen among the males (52.3%), in the age group 51 to 60 years (26.8%) and among the patients undergoing surgical intervention to deal with cancer (34.2%). The prevalence of wound infection was significantly affected by gender, age, and treatment regimen (P < .01). Out of the total 68 S. aureus isolates, 38 (44.1%) were deemed as Methicillin-resistant Staphylococcus aureus (MRSA). Among the 158 isolates, 85 (53.8%) were multi-drug resistant (MDR). Cefepime was the most effective antibiotic for Gram positive isolates whereas both imipenem and meropenem were found to be equally more effective for Gram negative isolates.

Conclusion:

This study suggests that patients with malignancies harbor pathogenic bacteria; therefore, prudent use of antibiotics is essential to prevent the emergence of MDR pathogens.

Fluoroquinolone Prophylaxis Selects for Meropenem-nonsusceptible Pseudomonas aeruginosa in Patients With Hematologic Malignancies and Hematopoietic Cell Transplant Recipients

BACKGROUND

In Pseudomonas aeruginosa, fluoroquinolone exposure promotes resistance to carbapenems through upregulation of efflux pumps and transcriptional downregulation of the porin OprD. Evidence of this effect among hematologic malignancy (HM) patients or hematopoietic cell transplant (HCT) recipients receiving fluoroquinolone prophylaxis for neutropenia is lacking.

METHODS

We retrospectively evaluated episodes of P. aeruginosa bloodstream infections in HM patients or HCT recipients over a 7-year period at our institution. We determined the association of fluoroquinolone prophylaxis at the time of infection with meropenem susceptibility of P. aeruginosa breakthrough isolates and risk factors for meropenem nonsusceptibility. Whole-genome sequencing (WGS) and phenotypic assessments of meropenem efflux pump activity were performed on select isolates to determine the mechanisms of meropenem resistance.

RESULTS

We analyzed 55 episodes of P. aeruginosa bacteremia among 51 patients. Breakthrough bacteremia while on fluoroquinolone prophylaxis was associated with nonsusceptibility to meropenem, but not to antipseudomonal β-lactams or aminoglycosides. The receipt of fluoroquinolone prophylaxis was independently predictive of bacteremia with a meropenem-nonsusceptible isolate. All meropenem-nonsusceptible isolates analyzed by WGS contained oprD inactivating mutations, and all meropenem-nonsusceptible isolates tested demonstrated reductions in the meropenem minimum inhibitory concentration in the presence of an efflux pump inhibitor. A phylogenetic analysis based on WGS revealed several clusters of closely related isolates from different patients.

CONCLUSIONS

Fluoroquinolone prophylaxis in HM patients and HCT recipients is associated with breakthrough bacteremia with meropenem-nonsusceptible P. aeruginosa strains, likely due to both mutations increasing efflux pump activity and the epidemiology of P. aeruginosa bloodstream infections in our patient population.

The Value of Adding Surveillance Cultures to Fluoroquinolone Prophylaxis in the Management of Multiresistant Gram Negative Bacterial Infections in Acute Myeloid Leukemia

Multidrug resistant Gram-Negative Bacterial Infections (MR-GNBI) are an increasing cause of mortality in acute myeloid leukemia (AML), compromising the success of antineoplastic therapy. We prospectively explored a novel strategy, including mandatory fluoroquinolone prophylaxis, weekly surveillance cultures (SC) and targeted antimicrobial therapy for febrile neutropenia, aimed to reduce infectious mortality due to MR-GNBI. Over 146 cycles of chemotherapy, cumulative incidence of colonization was 50%. Half of the colonizations occurred in the consolidation phase of treatment. Application of this strategy led to a significant reduction in the incidence of GNB and carbapenemase-producing Klebisella pneumoniae (cpKp) species, resulting in a reduction of infectious mortality (HR 0.35 [95%, CI 0.13–0.96], p = 0.042). In multivariate analysis, fluroquinolone prophylaxis in addition to SC was associated with improved survival (OR 0.55 [95% CI 0.38–0.79], p = 0.001). Targeted therapy for colonized patients did not overcome the risk of death once cpKp or XDR Pseudomonas aeruginosa infections were developed. Mortality rate after transplant was similar between colonized and not colonized patients. However only 9% of transplanted patients were colonized by cpkp. In conclusion, colonization is a common phenomenon, not limited to the induction phase. This strategy reduces infectious mortality by lowering the global incidence of GN infections and the spread of resistant species.

QT prolongation in patients with acute leukemia or high-risk myelodysplastic syndrome prescribed antifungal prophylaxis during chemotherapy-induced neutropenia

Benefits of serial electrocardiographic (ECG) monitoring to detect QT prolongation in patients with hematological malignancies remain unclear. This retrospective, single-center, study evaluated 316 adult acute leukemia and high-risk MDS patients who received 11,775 patient-days of voriconazole prophylaxis during induction chemotherapy. Of these, 37 patients (16.2%) experienced QTc prolongation. Medications associated with QTc prolongation included furosemide, haloperidol, metronidazole, mirtazapine, prochlorperazine, and venlafaxine. Hypokalemia and hypomagnesemia were also significantly associated with QTc prolongation (HR 3.15; p = .003 and HR 6.47, p = .007, respectively). Management modifications due to QTc prolongation included discontinuation of QT prolonging medications (n = 25), more aggressive electrolyte repletion (n = 5), and enhanced ECG monitoring (n = 3). One patient with multiple QT prolonging factors experienced possible Torsades de Pointes. Overall mortality was 15% with no cardiac-related deaths. Serial ECG monitoring during induction chemotherapy can be tailored proportionally to QT-prolonging risk factors. Management should include aggressive electrolyte repletion and avoidance of concurrent QT prolonging medications.

Incidence and Outcomes of Bacterial Bloodstream Infections during Acute Graft-versus-Host Disease Involving the Gastrointestinal Tract after Hematopoietic Cell Transplantation

Despite the association of acute graft-versus-host disease (aGVHD) and bacterial bloodstream infections (BSIs) in hematopoietic cell transplant (HCT) recipients, relatively little is known about BSIs, specifically during gastrointestinal (GI) tract aGVHD (aGHVD-GI). The purpose of this study was to evaluate the incidence, risk factors, and mortality of BSIs complicating aGVHD-GI. This was a retrospective review of adult HCT recipients with grades I to IV aGVHD-GI between January 2009 and October 2017 at Oregon Health and Sciences University. BSIs occurring within 30 days of onset of aGVHD-GI were included. BSIs were categorized as "clinical" or "surveillance" based on chart review. A subgroup analysis of patients with grade IV aGVHD-GI examined potential BSI risk factors and cumulative survival at 30 and 45 days after onset of aGVHD-GI. Included were 229 patients. There were 45 unique BSIs in 39 patients (17%): 31 clinical (68.9%) and 14 surveillance (32.1%). The median time from aGVHD-GI onset to BSI was 18.5 days. BSIs were significantly more common during grade IV aGVHD-GI compared with grades I, II, or III. Fifty-two organisms were isolated during BSIs: 23 (44.2%) gram-positive and 29 (55.8%) gram-negative. Sixteen BSIs (36%) occurred during antibiotic exposure, and those were more likely to be caused by multidrug-resistant organisms. Prior BSI occurring between the time of HCT and onset of aGVHD-GI and receipt of etanercept for steroid-refractory aGVHD-GI were independently associated with BSI. Eight patients, all with grade IV aGVHD, representing 30.8% of patients with BSI in this subgroup, experienced infection-associated mortality. Cumulative survival at days 30 and 45 after onset of grade IV aGVHD-GI was similar among patients with and without BSI. BSI is a common complication of grade IV aGVHD-GI, resulting in significant infection-associated mortality. Interventions targeting those at highest risk may be warranted.

Infections in Allogeneic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has become a widely used modality of therapy for a variety of malignant and nonmalignant diseases. Despite advances in pharmacotherapy and transplantation techniques, infection remains one of the most severe and frequently encountered complications of allo-HSCT.

This chapter will address the risk factors for development of infection following allo-HSCT, including those related to the host, the conditioning regimen, and the graft, as well as the timing of opportunistic infections after allo-HSCT. The most common bacterial, viral, fungal, and parasitic infections, as well as issues surrounding their diagnostics and treatment, will be discussed. Finally, this chapter will address vaccination and other preventative strategies to be utilized when caring for patients undergoing allo-HSCT.

Bacterial profile, antibiotic resistance pattern and associated factors among cancer patients at University of Gondar Hospital, Northwest Ethiopia

INTRODUCTION

Cancer is alarmingly increased in developing countries like Ethiopia, where multidrug resistant bacterial infection is rampant. The aim of this study was to determine the bacterial profile, antimicrobial resistance pattern, and associated factors among cancer patients attending University of Gondar Hospital.

METHODS

A consecutive 216 cancer patients were recruited from February to April, 2017. Socio-demographic and clinical data were collected using a structured questionnaire. Culture and antibiotic resistance were done following standard microbiological procedures.

RESULT

The overall prevalence of bacterial infection was 19.4%. The predominant bacterial isolates were Staphylococcus aureus (28.6%), followed by coagulase negative staphylococci (26.2%) and Escherichia coli (21.4%). Multidrug resistance was detected in 46.5% bacterial isolates. Methicillin resistance was detected in 25% of S. aureus and in 45.5% of coagulase negative staphylococci. Fluoroquinolone resistance was detected in 33.3% of E. coli isolates. Cancer patients with solid tumor, started cancer therapy, and being symptomatic had higher odds of culture positivity.

CONCLUSION

The overall burden of bacterial infection among cancer patients is considerably high. The findings of this study inform baseline information for policymakers and call for additional studies with large isolates in different cancer treatment centers in the region and in the country to better understand the bacterial isolate and resistance pattern.

Effect of Levofloxacin Prophylaxis on Bacteremia in Children With Acute Leukemia or Undergoing Hematopoietic Stem Cell Transplantation: A Randomized Clinical Trial

Importance

Bacteremia causes considerable morbidity among children with acute leukemia and those undergoing hematopoietic stem cell transplantation (HSCT). There are limited data on the effect of antibiotic prophylaxis in children.

Objective

To determine the efficacy and risks of levofloxacin prophylaxis in children receiving intensive chemotherapy for acute leukemia or undergoing HSCT.

Design, Setting, and Participants

In this multicenter, open-label, randomized trial, patients (6 months-21 years) receiving intensive chemotherapy were enrolled (September 2011-April 2016) in 2 separate groups-acute leukemia, consisting of acute myeloid leukemia or relapsed acute lymphoblastic leukemia, and HSCT recipients-at 76 centers in the United States and Canada, with follow-up completed September 2017.

Interventions

Patients with acute leukemia were randomized to receive levofloxacin prophylaxis for 2 consecutive cycles of chemotherapy (n = 100) or no prophylaxis (n = 100). Those undergoing HSCT were randomized to receive levofloxacin prophylaxis during 1 HSCT procedure (n = 210) or no prophylaxis (n = 214).

Main Outcomes and Measures

The primary outcome was the occurrence of bacteremia during 2 chemotherapy cycles (acute leukemia) or 1 transplant procedure (HSCT). Secondary outcomes included fever and neutropenia, severe infection, invasive fungal disease, Clostridium difficile-associated diarrhea, and musculoskeletal toxic effects.

Results

A total of 624 patients, 200 with acute leukemia (median [interquartile range {IQR}] age, 11 years [6-15 years]; 46% female) and 424 undergoing HSCT (median [IQR] age, 7 years [3-14]; 38% female), were enrolled. Among 195 patients with acute leukemia, the likelihood of bacteremia was significantly lower in the levofloxacin prophylaxis group than in the control group (21.9% vs 43.4%; risk difference, 21.6%; 95% CI, 8.8%-34.4%, P = .001), whereas among 418 patients undergoing HSCT, the risk of bacteremia was not significantly lower in the levofloxacin prophylaxis group (11.0% vs 17.3%; risk difference, 6.3%; 95% CI, 0.3%-13.0%; P = .06). Fever and neutropenia were less common in the levofloxacin group (71.2% vs 82.1%; risk difference, 10.8%; 95% CI, 4.2%-17.5%; P = .002). There were no significant differences in severe infection (3.6% vs 5.9%; risk difference, 2.3%; 95% CI, -1.1% to 5.6%; P = .20), invasive fungal disease (2.9% vs 2.0%; risk difference, -1.0%; 95% CI, -3.4% to 1.5%, P = .41), C difficile-associated diarrhea (2.3% vs 5.2%; risk difference, 2.9%; 95% CI, -0.1% to 5.9%; P = .07), or musculoskeletal toxic effects at 2 months (11.4% vs 16.3%; risk difference, 4.8%; 95% CI, -1.6% to 11.2%; P = .15) or at 12 months (10.1% vs 14.4%; risk difference, 4.3%; 95% CI, -3.4% to 12.0%; P = .28) between the levofloxacin and control groups.

Conclusions and Relevance

Among children with acute leukemia receiving intensive chemotherapy, receipt of levofloxacin prophylaxis compared with no prophylaxis resulted in a significant reduction in bacteremia. However, there was no significant reduction in bacteremia for levofloxacin prophylaxis among children undergoing HSCT.

Ciprofloxacin prophylaxis during autologous stem cell transplantation for multiple myeloma in patients with a high rate of fluoroquinolone-resistant gram-negative bacteria colonization

BACKGROUND

Ciprofloxacin prophylaxis used to be a standard precaution during autologous stem cell transplantation. Its benefit, with a high prevalence of fluoroqinolone resistance in the population, has recently been under scrutiny.

OBJECTIVE

To evaluate the impact of cessation of ciprofloxacin prophylaxis during stem cell transplantation for multiple myeloma.

PATIENTS AND METHODS

Data from 104 patients with multiple myeloma transplanted during the period from January 2013 to April 2015 were retrospectively reviewed. 67 received standard ciprofloxacin prophylaxis (group A) and 37 received no antibacterial prophylaxis (group B).

RESULTS

Febrile episodes during neutropenia, bloodstream infection (BSI) and mortality in these two cohorts were evaluated. Gram negative BSI was assessed for the colonization of quinolone-resistant gram-negative pathogens. Secondary Clostridium difficile enterocolitis presence was determined in both cohorts. There were 42 (63%), 7 (10%), and 0 febrile episodes, BSI and gram-negative BSI respectively in group A, and 34 (92%), 12 (32%), and 4 (11%) respectively in group B. The differences in the number of febrile episodes (P=0.0011) and deaths (P=0.0427) were statistically significance. Mortality was 0 and 3 (8%) in group A and group B, respectively. There was no significant difference in colonization with quinolone-resistant gram negative pathogens (25 (37%) versus 11 (30%)) between groups. The occurrence of Clostridium difficile colitis was the same in both groups.

CONCLUSION

We resumed ciprofloxacin prophylaxis for the following reasons. There was a significant reduction in febrile episodes, and consequently a sparing effect of antibiotics used for treatment of this condition. No difference in Clostridium difficile colitis occurred and the mortality rate of 8% in group B was unacceptably high.

Antimicrobial Prophylaxis for Adult Patients With Cancer-Related Immunosuppression: ASCO and IDSA Clinical Practice Guideline Update

PURPOSE

To provide an updated joint ASCO/Infectious Diseases Society of America (IDSA) guideline on antimicrobial prophylaxis for adult patients with immunosuppression associated with cancer and its treatment.

METHODS

ASCO and IDSA convened an update Expert Panel and conducted a systematic review of relevant studies from May 2011 to November 2016. The guideline recommendations were based on the review of evidence by the Expert Panel.

RESULTS

Six new or updated meta-analyses and six new primary studies were added to the updated systematic review.

RECOMMENDATIONS

Antibacterial and antifungal prophylaxis is recommended for patients who are at high risk of infection, including patients who are expected to have profound, protracted neutropenia, which is defined as < 100 neutrophils/µL for > 7 days or other risk factors. Herpes simplex virus-seropositive patients undergoing allogeneic hematopoietic stem-cell transplantation or leukemia induction therapy should receive nucleoside analog-based antiviral prophylaxis, such as acyclovir. Pneumocystis jirovecii prophylaxis is recommended for patients receiving chemotherapy regimens that are associated with a > 3.5% risk for pneumonia as a result of this organism (eg, those with ≥ 20 mg prednisone equivalents daily for ≥ 1 month or on the basis of purine analog usage). Treatment with a nucleoside reverse transcription inhibitor (eg, entecavir or tenofovir) is recommended for patients at high risk of hepatitis B virus reactivation. Recommendations for vaccination and avoidance of prolonged contact with environments that have high concentrations of airborne fungal spores are also provided within the updated guideline. Additional information is available at www.asco.org/supportive-care-guidelines .

Efficacy of selective digestive decontamination in patients with multiple myeloma undergoing high-dose chemotherapy and autologous stem cell transplantation

Selective digestive decontamination (SDD) with the oral, non-absorbable antimicrobial substances gentamicin, vancomycin and amphotericin B was optionally used at our institution to reduce the risk of gastrointestinal tract derived infections in multiple myeloma (MM) patients undergoing high-dose chemotherapy with subsequent autologous stem cell transplantation (HDCT/ASCT). The majority of patients received sulfamethoxazole-trimethoprim as pneumocystis pneumonia prophylaxis. From 203 patients receiving their first HDCT/ASCT between 2009 and 2015, we compared retrospectively 90 patients receiving SDD to 113 patients not receiving SDD. The administration of SDD was associated with a reduction of bacterial infections after HDCT/ASCT (overall: 8% versus 24%, p = .002; gram-negative pathogens: 1% versus 11%, p = .006) and less use of systemic antibiotics (62% versus 77%, p = .022). Omission of SDD was an independent risk factor for developing neutropenic fever and bloodstream infections. SDD could be an option to reduce bacterial infections in patients undergoing HDCT/ASCT that needs to be tested in prospective trials.

A comparison of levofloxacin and oral third-generation cephalosporins as antibacterial prophylaxis in acute leukaemia patients during chemotherapy-induced neutropenia

Background

There is demonstrated benefit with fluoroquinolones as infection prophylaxis in neutropenic patients; however, side effects, drug interactions and increasing resistance necessitate investigation of alternative therapies.

Objectives

To compare the incidence of febrile neutropenia in high-risk patients with haematological malignancy receiving a fluoroquinolone with those receiving an oral third-generation cephalosporin (OTGC) as antibacterial prophylaxis during chemotherapy-induced neutropenia.

Methods

A retrospective, matched, single-centre study comparing clinical and microbiological outcomes in acute leukaemia patients receiving fluoroquinolones versus OTGCs as antibacterial prophylaxis after chemotherapy.

Results

A total of 120 patients (levofloxacin n = 80, OTGC n = 40) were included and matched. The 30 day incidence of febrile neutropenia was 89.7% (95% CI = 82.4-93.9). The rates of febrile neutropenia were similar between antimicrobials (OTGC versus levofloxacin HR = 0.90, 95% CI = 0.54-1.52, P = 0.70). The most frequent site of infection was the bloodstream (line related) (n = 24, 62%) and the majority (n = 28, 72%) of infections were caused by Gram-positive organisms. Groups were similar in terms of site of infection (P = 0.91) and morphology of recovered microorganisms (P = 0.74). There were significantly more cultures positive for Enterobacter spp. in the OTGC group (P = 0.043). Three patients died during follow-up (from first dose up to 30 days after the last dose) (30 day survival = 99.2%, 95% CI = 97.5-100), with only two of the reported deaths attributable to infection.

Conclusions

These findings demonstrate comparable rates of febrile neutropenia and culture positivity with an increase in cultures positive for Enterobacter spp. when OTGCs are compared with levofloxacin for antibacterial prophylaxis during chemotherapy-induced neutropenia. Further prospective, randomized investigation is warranted.

Incidence, Risk Factors and Outcome of Pre-engraftment Gram-Negative Bacteremia After Allogeneic and Autologous Hematopoietic Stem Cell Transplantation: An Italian Prospective Multicenter Survey

Background

Gram-negative bacteremia (GNB) is a major cause of illness and death after hematopoietic stem cell transplantation (HSCT), and updated epidemiological investigation is advisable.

Methods

We prospectively evaluated the epidemiology of pre-engraftment GNB in 1118 allogeneic HSCTs (allo-HSCTs) and 1625 autologous HSCTs (auto-HSCTs) among 54 transplant centers during 2014 (SIGNB-GITMO-AMCLI study). Using logistic regression methods. we identified risk factors for GNB and evaluated the impact of GNB on the 4-month overall-survival after transplant.

Results

The cumulative incidence of pre-engraftment GNB was 17.3% in allo-HSCT and 9% in auto-HSCT. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most common isolates. By multivariate analysis, variables associated with GNB were a diagnosis of acute leukemia, a transplant from a HLA-mismatched donor and from cord blood, older age, and duration of severe neutropenia in allo-HSCT, and a diagnosis of lymphoma, older age, and no antibacterial prophylaxis in auto-HSCT. A pretransplant infection by a resistant pathogen was significantly associated with an increased risk of posttransplant infection by the same microorganism in allo-HSCT. Colonization by resistant gram-negative bacteria was significantly associated with an increased rate of infection by the same pathogen in both transplant procedures. GNB was independently associated with increased mortality at 4 months both in allo-HSCT (hazard ratio, 2.13; 95% confidence interval, 1.45-3.13; P <.001) and auto-HSCT (2.43; 1.22-4.84; P = .01).

Conclusions

Pre-engraftment GNB is an independent factor associated with increased mortality rate at 4 months after auto-HSCT and allo-HSCT. Previous infectious history and colonization monitoring represent major indicators of GNB.

Clinical Trials registration

NCT02088840.

Impact of fluoroquinolone prophylaxis during neutropenia on bloodstream infection: Data from a surveillance program in 8755 patients receiving high-dose chemotherapy for haematologic malignancies between 2009 and 2014

OBJECTIVES

Antibacterial chemoprophylaxis with fluoroquinolones (FQPx) has been commonly used in cancer patients with neutropenia, but its efficacy has been challenged by the emergence of fluoroquinolone resistance.

METHODS

The impact of FQPx on bloodstream infections (BSI) during neutropenia after high-dose chemotherapy for haematologic malignancies was evaluated through a multicenter hospital infection surveillance system for the period 2009-2014.

RESULTS

Among 8755 patients (4223 allogeneic [allo-] HSCT, 3602 autologous [auto-] HSCT, 930 high-dose chemotherapy for acute leukemia [HDC]), 5302 (61%) had received FQPx. Administration of FQPx was associated with fewer Gram-negative BSI in the overall study cohort patients (4.6% vs. 7.7%, adjusted subdistribution hazard ratio [aSHR] 0.59, 95%CI 0.50-0.70), in patients with HDC (3.7% vs. 9.2%, adjusted subdistribution hazard ratio [aSHR] 0.40, 95%CI 0.22-0.70) and auto-HSCT patients (4% vs. 9%, aSHR 0.43, 95%CI 0.33-0.56). In HDC patients, FQPx was associated with a marked reduction in all-cause mortality during neutropenia (2.3% vs. 7.8%, aSHR 0.30, 95%CI 0.15-0.58). Patients receiving FQPx had significantly more BSIs due to ESBL-positive Enterobacteriacea (0.8 vs. 0.3%, RR 2.2, 95%CI 1.17-4.26). BSIs by MRSA (n = 5) and VRE (n = 11) were rare in our cohort.

CONCLUSIONS

As used in the participating centers, FQPx was associated with reduced Gram-negative BSI and improved survival among HDC patients. Among HSCT patients, the benefits were less clear. If adapted to local resistance patterns and patient characteristics, FQPx still may be useful in the management of patients with haematologic malignancies.

Predictors of chemoradiation related febrile neutropenia prophylaxis in older adults - Experience from a limited resource setting

Aim

To identify risk factors that lower efficacy of antibiotic prophylaxis of febrile neutropenia among older patients on chemoradiation.

Background

Audit of institutional data showed that older adults are at higher risk of febrile neutropenia during chemoradiation. In limited resource settings widespread use of Granulocyte-Colony Stimulating Factor (G-CSF) is not economically feasible and antibiotics are used commonly. Despite compliance with antibiotics, prophylaxis is inadequate in many patients owing to patient and tumor related factors.

Materials and methods

Data from records of 219 older patients receiving antibiotic prophylaxis during chemoradiation were studied. Baseline assessment data and predisposing factors for febrile neutropenia were recorded. All patients received prophylactic fluoroquinolones. Incidence of febrile neutropenia and association with predisposing factors at baseline was analyzed by multiple logistic regression.

Results

38.4% developed febrile neutropenia despite compliance. Multiple logistic regression revealed geriatric assessment (G8) score and tumor stage to be significant predictors of febrile neutropenia while on antibiotics (p < 0.0001). Odds ratios for two significant predictors G8 score and tumor stage, respectively, were 2.9 (95% CI 1.8036-4.6815) and 2.7 (95% CI 1.7501-4.1318). Correlation between these two significant predictors was found to be low in our cohort (Spearman's coefficient of rank correlation (rho) - 0.431, p < 0.0001).

Conclusion

G8 score and tumor burden are significant predictors of efficacy of antibiotic prophylaxis among older adults receiving chemoradiation. In older patients having poor G8 scores and advanced tumors, antibiotic prophylaxis is unsuitable. Interestingly, co-morbidities and poor performance status did not impact efficacy of antibiotic prophylaxis among our elderly patients.

Infectious complications after hematopoietic stem cell transplantation: current status and future perspectives in Korea

Hematopoietic stem cell transplantation (HSCT) is a treatment for hematologic malignancies, immune deficiencies, or genetic diseases, ect. Recently, the number of HSCTs performed in Korea has increased and the outcomes have improved. However, infectious complications account for most of the morbidity and mortality after HSCT. Post-HSCT infectious complications are usually classified according to the time after HSCT: pre-engraftment, immediate post-engraftment, and late post-engraftment period. In addition, the types and risk factors of infectious complications differ according to the stem cell source, donor type, conditioning intensity, region, prophylaxis strategy, and comorbidities, such as graft-versushost disease and invasive fungal infection. In this review, we summarize infectious complications after HSCT, focusing on the Korean perspectives.

Prophylactic Measures During Induction for Acute Myeloid Leukemia

PURPOSE OF REVIEW

Improved management of infectious complications of acute myeloid leukemia (AML) has contributed substantially to the success of care over the past half century. An important approach to reducing infectious complications during the induction period of chemotherapy involves the use of prophylactic antibacterial, antiviral, and antifungal agents targeting likely pathogens.

RECENT FINDINGS

There is not a one-size-fits-all approach to prophylaxis; every patient undergoing induction therapy should be evaluated individually and within the context of local microbiologic epidemiology and host risk factors. Pharmacologic and non-pharmacologic interventions as well as novel diagnostic platforms can help mitigate the risk of life-threatening infection in patients with AML who undergo induction chemotherapy.

Epidemiology of bloodstream infections after myeloablative and non-myeloablative allogeneic hematopoietic stem cell transplantation: A single-center cohort study

BACKGROUND

Patients who undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT) often develop bloodstream infections (BSI). We aimed to describe the etiologies and antibiotic resistance patterns of BSI after allo-HSCT, and, as knowledge about the impact of conditioning regimen is limited, we looked at the incidence, timing, risk factors, and mortality of BSI separately for myeloablative (MA)- and non-myeloablative (NMA)-conditioned patients.

METHODS

All 460 patients (207 MA- and 253 NMA-conditioned) who underwent their first allo-HSCT at our center from 2008 to 2013 were included in a historical cohort. BSI were registered from initiation of conditioning to day 360 after transplantation.

RESULTS

BSI occurred in 34% (95% confidence interval [CI]: 28%, 41%) of MA-conditioned patients and in 17% (95% CI: 12%, 22%) of NMA-conditioned patients. Of all isolates, 68% were gram-positive bacteria (GPB), 23% gram-negative bacteria (GNB), and 9% fungi. The GPB/GNB ratio declined from 2008 to 2014 (P for trend <.01). Of all GNB, 47% were multidrug resistant (MDR), but the proportion declined over the study period. In a multivariate Cox regression model, only acute graft-versus-host disease was associated with a higher hazard of first BSI (hazard ratio 2.50, 95% CI: 1.48, 4.21). Overall 30-day survival after a BSI was higher for MA-conditioned patients than for NMA-conditioned patients (89% vs 74%, P=.04).

CONCLUSION

MA-conditioned patients experience BSI more often than NMA-conditioned patients in the year after allo-HSCT. While BSI are increasingly caused by GNB, the rate of MDR GNB is declining.

Complications of hematopoietic stem cell transplantation: Bacterial infections

Bacterial infections remain a common complication of hematopoietic stem cell transplantation (HSCT), especially in the pre-engraftment phase. The risk of bacterial infections is mainly related to neutropenia, mucositis, and the presence of vascular lines. Most parts of the world have witnessed a shift in epidemiology toward Gram-negative bacteria; a large proportion of which are resistant to fluoroquinolones, extended-spectrum beta-lactams, carbapenems, and in some units even colistin. Meticulous infection control practices are essential for prevention of bacterial infections in HSCT. The role of routine prophylactic antibiotics is limited in settings with high rates of bacterial resistance. If used, prophylactic antibiotics should be limited to high-risk patients, and the agents are selected based on local resistance profiles. Neutropenic fever is a medical emergency in most HSCT recipients. Prompt clinical evaluation is paramount, along with the intravenous administration of appropriate empiric antimicrobials, typically an antipseudomonal beta-lactam agent. Glycopeptides should only be considered if the patient is hemodynamically unstable or Gram-positive infection is suspected. Additional Gram-negative agents, such as colistin or aminoglycosides, may be added if extensive Gram-negative resistance is expected. To mitigate increasing bacterial resistance, empiric antibiotic regimens should be rationalized or discontinued as soon as possible.

Incomplete recovery of the fecal flora of hematological patients with neutropenia and repeated fluoroquinolone prophylaxis

Background

Routine fluoroquinolone prophylaxis in neutropenic patients with hematological malignancies is still controversial, because of antibiotic resistance concerns. The recovery of the fecal microbiota to the initial composition in patients receiving multiple courses of quinolone prophylaxis and repeated chemotherapy has not been evaluated.

Methods

We prospectively examined the changes in the fecal bacterial composition before and after levofloxacin prophylaxis. A sequential observation of bacterial resistance in patients receiving multiple prophylactic courses was also conducted.

Results

In this trial, 68 cases, including (35 with the first course and 33 with the second and subsequent courses) were registered. The disappearance of quinolone-susceptible (QS) Entero-bacteriaceae and dominant emergence of quinolone-resistant (QR) coagulase negative staphylococci (CNS) and QR Enterococci were observed after the first prophylaxis. The detection of QS Enterobacteriaceae was recovered before the second and subsequent courses to a level of the initial composition (28/35 samples, 80.0% before the first course vs 23/33 samples, 69.7% before the second and subsequent courses, P=0.41). In contrast, the detection rate of QR CNS and Enterococci significantly increased at the second and subsequent courses, even before prophylaxis (8/35 samples, 22.9% before the first course vs 20/33 samples, 60.6% before the second and subsequent courses, P=0.003). The incomplete recovery of the initial bacterial composition was associated with a prophylactic interval of within 30 days. Of the patients receiving multiple prophylactic courses, six had QR Escherichia coli, including extended-spectrum β-lactamase (ESBL) producers, at the first course, and four (66.3%) of the six patients had persistent detection of QR E. coli at the second course.

Conclusion

In patients receiving multiple courses of prophylactic quinolone, along with a common chemotherapy schedule, newly emergent resistant bacteria could be frequently persistent in their fecal flora.

Ciprofloxacin versus colistin prophylaxis during neutropenia in acute myeloid leukemia: two parallel patient cohorts treated in a single center

Patients undergoing intensive chemotherapy for acute myeloid leukemia are at high risk for bacterial infections during therapy-related neutropenia. However, the use of specific antibiotic regimens for prophylaxis in afebrile neutropenic acute myeloid leukemia patients is controversial. We report a retrospective evaluation of 172 acute myeloid leukemia patients who received 322 courses of myelosuppressive chemotherapy and had an expected duration of neutropenia of more than seven days. The patients were allocated to antibiotic prophylaxis groups and treated with colistin or ciprofloxacin through 2 different hematologic services at our hospital, as available. The infection rate was reduced from 88.6% to 74.2% through antibiotic prophylaxis (vs without prophylaxis; P=0.04). A comparison of both antibiotic drugs revealed a trend towards fewer infections associated with ciprofloxacin prophylaxis (69.2% vs 79.5% in the colistin group; P=0.07), as determined by univariate analysis. This result was confirmed through multivariate analysis (OR: 0.475, 95%CI: 0.236-0.958; P=0.041). The prophylactic agents did not differ with regard to the microbiological findings (P=0.6, not significant). Of note, the use of ciprofloxacin was significantly associated with an increased rate of infections with pathogens that are resistant to the antibiotic used for prophylaxis (79.5% vs 9.5% in the colistin group; P<0.0001). The risk factors for higher infection rates were the presence of a central venous catheter (P<0.0001), mucositis grade III/IV (P=0.0039), and induction/relapse courses (vs consolidation; P<0.0001). In conclusion, ciprofloxacin prophylaxis appears to be of particular benefit during induction and relapse chemotherapy for acute myeloid leukemia. To prevent and control drug resistance, it may be safely replaced by colistin during consolidation cycles of acute myeloid leukemia therapy.

Ciprofloxacin selects for RNA polymerase mutations with pleiotropic antibiotic resistance effects

OBJECTIVES

Resistance to the fluoroquinolone drug ciprofloxacin is commonly linked to mutations that alter the drug target or increase drug efflux via the major AcrAB-TolC transporter. Very little is known about other mutations that might also reduce susceptibility to ciprofloxacin. We discovered that an Escherichia coli strain experimentally evolved for resistance to ciprofloxacin had acquired a mutation in rpoB, the gene coding for the β-subunit of RNA polymerase. The aim of this work was to determine whether this mutation, and other mutations in rpoB, contribute to ciprofloxacin resistance and, if so, by which mechanism.

METHODS

Independent lineages of E. coli were evolved in the presence of ciprofloxacin and clones from endpoint cultures were screened for mutations in rpoB. Ciprofloxacin-selected rpoB mutations were identified and characterized in terms of effects on susceptibility and mode of action.

RESULTS

Mutations in rpoB were selected at a high frequency in 3 out of 10 evolved lineages, in each case arising after the occurrence of mutations affecting topoisomerases and drug efflux. All ciprofloxacin-selected rpoB mutations had a high fitness cost in the absence of drug, but conferred a competitive advantage in the presence of ciprofloxacin. RNA sequencing and quantitative RT-PCR analysis showed that expression of mdtK, encoding a multidrug efflux transporter, was significantly increased by the ciprofloxacin-selected rpoB mutations. The susceptibility phenotype was shown to depend on the presence of an active mdtK and a mutant rpoB allele.

CONCLUSIONS

These data identify mutations in RNA polymerase as novel contributors to the evolution of resistance to ciprofloxacin and show that the phenotype is mediated by increased MdtK-dependent drug efflux.

An overview of infectious complications after allogeneic hematopoietic stem cell transplantation

Infections are the most common and significant cause of mortality and morbidity after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The presence of neutropenia and mucosal damage are the leading risk factors in the early pre-engraftment phase. In the early post-engraftment phase, graft versus host disease (GvHD) induced infection risk is increased in addition to catheter related infections. In the late phase, in which reconstitution of cellular and humoral immunity continues, as well as the pathogens seen during the early post-engraftment phase, varicella-zoster virus and encapsulated bacterial infections due to impaired opsonization are observed. An appropriate vaccination schedule following the cessation of immunosuppressive treatment after transplantation, intravenous immunoglobulin administration, and antimicrobial prophylaxis with penicillin or macrolide antibiotics during immunosuppressive treatment for GvHD might decrease the risk of bacterial infections. Older age, severe mucositis due to toxicity of chemotherapy, gastrointestinal tract colonization, prolonged neutropenia, unrelated donor and cord blood originated transplantations, acute and chronic GvHD are among the most indicative clinical risk factors for invasive fungal infections. Mold-active anti-fungal prophylaxis is suggested regardless of the period of transplantation among high risk patients. The novel serological methods, including Aspergillus galactomannan antigen and beta-D-glucan detection and computed tomography are useful in surveillance. Infections due to adenovirus, influenza and respiratory syncytial virus are encountered in all phases after allo-HSCT, including pre-engraftment, early post-engraftment and late phases. Infections due to herpes simplex virus-1 and -2 are mostly seen during the pre-engraftment phase, whereas, infections due to cytomegalovirus and human herpes virus-6 are seen in the early post-engraftment phase and Epstein-Barr virus and varicella-zoster virus infections often after +100th day. In order to prevent mortality and morbidity of infections after allo-HSCT, the recipients should be carefully followed-up with appropriate prophylactic measures in the post-transplant period.

Bloodstream infections in neutropenic cancer patients: A practical update

Bloodstream infections (BSI) are among the most frequent complications in neutropenic cancer patients and, if caused by Gram-negative rods, are associated with high mortality. Thus, fever during neutropenia warrants prompt empirical antibiotic therapy which should be active against the most frequent Gram-negatives. In the last decade, there has been a worldwide increase in multidrug resistant (MDR) strains. In these cases, the traditional choices such as oral therapy, ceftazidime, cefepime, piperacillin-tazobactam, or even carbapenems, might be ineffective. Therefore novel de-escalation approach has been proposed for patients who are at high risk for infections due to MDR bacteria. It consists of starting antibiotics which cover the most probable resistant strain but it is narrowed down after 72 hours if no MDR pathogen is isolated. With increasing bacterial resistance, the benefit of fluoroquinolone prophylaxis during prolonged neutropenia remains to be confirmed. Antibiotic stewardship and infection control programs are mandatory in every cancer center.