High Rate of Inappropriate Antibiotics in Patients with Hematologic Malignancies and Pseudomonas aeruginosa Bacteremia following International Guideline Recommendations.

Optimal coverage of Pseudomonas aeruginosa is challenging in febrile neutropenic patients due to a progressive increase in antibiotic resistance worldwide. We aimed to detail current rates of resistance to antibiotics recommended by international guidelines for P. aeruginosa isolated from bloodstream infections (BSI) in patients with hematologic malignancies. Secondarily, we aimed to describe how many patients received inappropriate empirical antibiotic treatment (IEAT) and its impact on mortality. We conducted a retrospective, multicenter cohort study of the last 20 BSI episodes caused by P. aeruginosa in patients with hematologic malignancies from across 14 university hospitals in Spain. Of the 280 patients with hematologic malignancies and BSI caused by P. aeruginosa, 101 (36%) had strains resistant to at least one of the ß-lactam antibiotics recommended in international guidelines, namely, cefepime, piperacillin-tazobactam, and meropenem. Additionally, 21.1% and 11.4% of the strains met criteria for MDR and XDR P. aeruginosa, respectively. Even if international guidelines were followed in most cases, 47 (16.8%) patients received IEAT and 66 (23.6%) received inappropriate ß-lactam empirical antibiotic treatment. Thirty-day mortality was 27.1%. In the multivariate analysis, pulmonary source (OR 2.22, 95% CI 1.14 to 4.34) and IEAT (OR 2.67, 95% CI 1.37 to 5.23) were factors independently associated with increased mortality. We concluded that P. aeruginosa-causing BSI in patients with hematologic malignancies is commonly resistant to antibiotics recommended in international guidelines, which is associated with frequent IEAT and higher mortality. New therapeutic strategies are needed. IMPORTANCE Bloodstream infection (BSI) caused by P. aeruginosa is related with an elevated morbidity and mortality in neutropenic patients. For this reason, optimal antipseudomonal coverage has been the basis of all historical recommendations in the empirical treatment of febrile neutropenia. However, in recent years the emergence of multiple types of antibiotic resistances has posed a challenge in treating infections caused by this microorganism. In our study we postulated that P. aeruginosa-causing BSI in patients with hematologic malignancies is commonly resistant to antibiotics recommended in international guidelines. This observation is associated with frequent IEAT and increased mortality. Consequently, there is a need for a new therapeutic strategy.

Resistance to empirical ß-lactams recommended in febrile neutropenia guidelines in Gram-negative bacilli bloodstream infections in Spain: a multicentre study.

OBJECTIVES: To describe current resistance to the ß-lactams empirically recommended in the guidelines in bloodstream infection (BSI) episodes caused by Gram-negative bacilli (GNB). METHODS: Retrospective, multicentre cohort study of the last 50 BSI episodes in haematological patients across 14 university hospitals in Spain. Rates of inappropriate empirical antibiotic therapy (IEAT) and impact on mortality were evaluated. RESULTS: Of the 700 BSI episodes, 308 (44%) were caused by GNB, mainly Escherichia coli (141; 20.1%), Klebsiella spp. (56; 8%) and Pseudomonas aeruginosa (48; 6.9%). Among GNB BSI episodes, 80 (26%) were caused by MDR isolates. In those caused by Enterobacterales, 25.8% were ESBL producers and 3.5% were carbapenemase producers. Among P. aeruginosa BSI episodes, 18.8% were caused by MDR isolates. Overall, 34.7% of the isolated GNB were resistant to at least one of the three ß-lactams recommended in febrile neutropenia guidelines (cefepime, piperacillin/tazobactam and meropenem). Despite extensive compliance with guideline recommendations (91.6%), 16.6% of BSI episodes caused by GNB received IEAT, which was more frequent among MDR GNB isolates (46.3% versus 6.1%; P < 0.001). Thirty day mortality was 14.6%, reaching 21.6% in patients receiving IEAT. CONCLUSIONS: Current resistance to empirical ß-lactams recommended in febrile neutropenia guidelines is exceedingly high and IEAT rates are greater than desired. There is an urgent need to adapt guidelines to current epidemiology and better identify patients with a high risk of developing MDR GNB infection.

Analyzing the capability of PSP, PCT and sCD25 to support the diagnosis of infection in cancer patients with febrile neutropenia.

Background Early diagnosis of infection is essential for the initial management of cancer patients with chemotherapy-associated febrile neutropenia (FN). In this study, we have evaluated two emerging infection biomarkers, pancreatic stone protein (PSP) and soluble receptor of interleukin 2, known as soluble cluster of differentiation 25 (sCD25), for the detection of an infectious cause in FN, in comparison with other commonly used infection biomarkers, such as procalcitonin (PCT). Methods A total of 105 cancer patients presenting to the emergency department were prospectively enrolled. We observed 114 episodes of chemotherapy-associated FN. At presentation, a blood sample was collected for the measurement of PCT, PSP and sCD25. In order to evaluate the discriminatory ability of these markers for the diagnosis of infection, the area under the curve (AUC) of the receiver operating characteristic curves was calculated. Results Infection was documented in 59 FN episodes. PCT, PSP and sCD25 levels were significantly higher in infected patients. PCT was the biomarker with the highest diagnostic accuracy for infection (AUC: 0.901), whereas PSP and sCD25 showed a similar performance, with AUCs of 0.751 and 0.730, respectively. In a multivariable analysis, PCT and sCD25 were shown to be independently associated with infection. Conclusions Two novel biomarkers, PSP and sCD25, correlated with infection in cancer patients with chemotherapy-associated FN, but neither PSP nor sCD25 improved the performance of PCT. Based on the results obtained, the introduction of these novel biomarkers as a tool for the diagnosis of infection in this patient group is not recommended.

Prognostic value of procalcitonin and lipopolysaccharide binding protein in cancer patients with chemotherapy-associated febrile neutropenia presenting to an emergency department.

INTRODUCTION: Cancer patients with chemotherapy-induced febrile neutropenia are a heterogeneous group with a significant risk of serious medical complications. In these patients, the Multinational Association for Supportive Care in Cancer (MASCC) score is the most widely used tool for risk-stratification. The aim of this prospective study was to analyse the value of procalcitonin (PCT) and lipopolysaccharide binding protein (LBP) to predict serious complications and bacteraemia in cancer patients with febrile neutropenia, compared with MASCC score. MATERIALS AND METHODS: Data were collected from 111 episodes of febrile neutropenia admitted consecutively to the emergency department. In all of them, MASCC score was calculated and serum samples were collected for measurement of PCT and LBP by well-established methods. The main and secondary outcomes were the development of serious complications and bacteraemia, respectively. RESULTS: A serious complication occurred in 20 (18%) episodes and in 16 (14%) bacteraemia was detected. Areas under the receiver operating characteristic curve (ROC AUC) of MASCC score, PCT and LBP to select low-risk patients were 0.83 (95% confidence interval (CI): 0.74 - 0.89), 0.85 (95% CI: 0.77 - 0.91) and 0.70 (95% CI: 0.61 - 0.78), respectively. For bacteraemia, MASCC score, PCT and LBP showed ROC AUCs of 0.74 (95% CI: 0.64 - 0.82), 0.86 (95% CI: 0.78 - 0.92) and 0.76 (95% CI: 0.67 - 0.83), respectively. CONCLUSION: A single measurement of PCT performs similarly as MASCC score to predict serious medical complications in cancer patients with febrile neutropenia and can be a useful tool for risk stratification. Besides, low PCT concentrations can be used to rule-out the presence of bacteraemia.

Value of lipopolysaccharide binding protein as diagnostic marker of infection in adult cancer patients with febrile neutropenia: comparison with C-reactive protein, procalcitonin, and interleukin 6.

PURPOSE: Early detection of infection is essential for initial management of cancer patients with chemotherapy-associated febrile neutropenia in the emergency department. In this study, we evaluated lipopolysaccharide binding protein (LBP) as predictor for infection in febrile neutropenia and compared with other biomarkers previously studied: C-reactive protein (CRP), procalcitonin (PCT), and interleukin (IL)-6. METHODS: A total of 61 episodes of chemotherapy-associated febrile neutropenia in 58 adult cancer patients were included. Serum samples were collected on admission at emergency department and CRP, LBP, PCT, and IL-6 were measured. Patients were classified into fever of unknown origin and infection, including microbiologically and clinically documented infection, groups. Receiver operating characteristic (ROC) curve analysis was performed for each biomarker for the diagnosis of infection. RESULTS: Thirty-two of the 61 episodes were classified as infection. On admission, CRP, PCT, IL-6, and LBP were significantly increased in patients with infection compared to fever of unknown origin group. Area under the ROC curve (AUC ROC) of CRP, PCT, IL-6, and LBP for discriminating both groups was 0.77, 0.88, 0.82, and 0.82, respectively, without significant difference between them. The combination of IL-6 and PCT or LBP did not lead to a significant improvement of the diagnostic accuracy of PCT or LBP alone. CONCLUSIONS: On admission, LBP has a similar diagnostic accuracy than PCT or IL-6 for the diagnosis of infection and might be used as additional diagnostic tool in adult cancer patients with chemotherapy-associated febrile neutropenia.