[Management of Carbapenem-resistant Enterobacteriaceae (CRE) infection in patients with hematological malignancies: Chinese consensus (2020)]

Population pharmacokinetics of polymyxin B: a systematic review

Background

Polymyxin B (PMB) is a basic cyclic polypeptide antibiotic produced by Bacillus polymyxa, and is one of the last options for treating multi-drug-resistant negative bacterial infections in clinical practice. In recent years, many population pharmacokinetic studies of PMB have been conducted. This paper sought to comprehensively summarize the characteristics of population pharmacokinetic models of PMB and provide a theoretical basis for the individualized use of PMB.

Methods

In this review, we systematically searched the PubMed and Embase databases to find articles on population pharmacokinetic models published from database establishment to August 2021.

Results

A total of 10 studies were included in this review, including studies on various types of severe infections caused by multi-drug-resistant bacteria, hospital-acquired infections with fibrosis and other male and female populations, and a study of 2 continuous renal replacement therapy (CRRT) patients, aged 16–94 years, who received PMB doses of 10–360 mg/day (0.13–3.45 mg/kg/day), at an administration time of 0.5–6 hours. First-order linear elimination was used in all the studies; a 1-compartment model was used in 5 studies, and a 2-compartment model was used in 5 studies. The most common covariates were creatinine clearance (CrCL) and body weight.

Discussion

Although these studies included several covariates and total clearance (CL) was close, but the external validation of some models was poorly correlated between the actual and predicted value. Novel or potential covariates represent important directions for further study.

[Analysing pathogenic bacterial spectrum and drug resistance of bloodstream infection in patients with allogeneic hematopoietic stem cell transplantation]

Objective: To elucidate the clinical characteristics of bloodstream infection in patients with allogeneic hematopoietic stem cell transplantation (allo-HSCT) in our hospital and improves the survival of transplant patients with bloodstream infection. Methods: Two hundred and ten patients with allo-HSCT from the Department of Hematology were retrospectively analyzed between October 2014 and September 2019. Pathogen distribution, drug resistance, risk factors, and outcomes were investigated in 49 allo-HSCT patients with bloodstream infections. Results: Forty-nine of 210 patients with allo-HSCT had bloodstream infection, and 59 pathogenic microorganisms were identified, mainly Gram-negative bacteria (67.8%) , of which E. coli had the highest incidence (23.7%) , CRO accounted for 42.5%, and Grampositive bacteria accounted for 23.7% (without vancomycin or linezolid-resistant strain) . Additionally, fungi accounted for 8.5%. Univariate analysis suggested that the risk factors of bloodstream infection were gender, pretransplant disease status, and conditioning regimen. In contrast, multivariate analysis showed that bloodstream infection was mainly related to conditioning regimens. Further grouping results showed that 77.6% of patients with neutropenia had bloodstream infections, and 22.4% of patients with non-neutropenia had bloodstream infections; 81.0% of patients with active infections before transplantation had bloodstream infections, while bloodstream infection occurred in 16.9% of patients without active infection. Survival analysis showed that long-term survival of patients with bloodstream infection is shorter than that of patients without bloodstream infection and long-term survival of patients with CRO infection is shorter than that of patients without CRO infection. The survival of patients with neutropenia longer than 14 d is shorter than that of patients with neutropenia shorter than 14 d. Furthermore, there is no correlation between whether there is an active infection before transplantation and whether they are in a neutropenic state at the time of infection and survival. Conclusion: Our results suggest that effective prevention of bloodstream infections from drug-resistant bacteria, particularly CRO, shortening the duration of neutropenia, eradication of potential infections before transplantation, and patient-adaptive conditioning could reduce transplant-related mortality and improve prognosis.

[Clinical characteristics and prognostic risk factors analysis of carbapenem-resistant organism in the department of hematology]

Objective: To study the distribution and drug resistance of Carbapenem-Resistant Organism (CRO) and to analysis the risk factors of CRO 30-day mortality. Methods: A total of 181 patients with CRO infection diagnosed in Department of Hematology, Fujian Medical University Union Hospital from January 2018 to June 2020 were retrospectively investigated. The clinical and laboratory data of the patients were collected, the prognosis of patients diagnosed with CRO infection in day 30 was followed up, and the risk factors of prognosis were analyzed. The clinical significance of Carbapenem-Resistant Enterobacteriaceae (CRE) active screening was further evaluated in the CRE subgroup. Results: Among the total of 181 CRO isolates, 47.2% were CRE, 37.0% were Pseudomonas aeruginosa, and 32.6% were Klebsiella pneumoniae, which were highly resistant to carbapenem and had high MIC value, 76.8% (139/181) of CRO were MIC of imipenem resistance≥16 μg/ml. The main sources of isolates were blood and sputum. The 30-day all-cause mortality rates of patients with CRO or CRE infection were (41.4±3.7) % and (44.7±5.4) %, respectively. The COX multivariate regression analysis showed that the level of procalcitonin >0.2 ng/ml and the MIC value of imipenem resistance ≥ 16 μg/ml were independent risk factors for 30-day mortality of CRO infected patients. The CRE subgroup analysis showed that MIC value of imipenem resistance ≥16 μg/ml were independent risk factors for 30-day mortality of CRE infected patients. The 30-day cumulative survival rate of patients with CRE active screening was higher than the patients without CRE active screening [ (68.0±9.3) % vs (50.0±6.5) %, P=0.21]. Conclusion: The high MIC value of imipenem resistance isolates seriously affects the prognosis of patients with CRO infection in the hematology department, and the mortality rate was high. CRE active screening is expected for early prevention, early diagnosis, and early treatment for high-risk patients.