[Perianal swabs surveillance cultures of Carbapenem-resistant Enterobacteriaceae(CRE) can be hints for CRE bloodstream infection in patients with hematological diseases]

High risk of bloodstream infection of carbapenem-resistant enterobacteriaceae carriers in neutropenic children with hematological diseases

BACKGROUND

Neutropenic children with hematological diseases were associated with higher morbidity of carbapenem-resistant enterobacteriaceae (CRE) blood-stream infection (BSI) or colonization. But it was still murky regarding clinical characteristics, antimicrobial susceptibility, and outcomes of CRE-BSI in these patients. We aimed to identify the potential risk factors for subsequent bacteremia and clinical outcome caused by CRE-BSI.

METHODS

Between 2008 and 2020, 2,465 consecutive neutropenic children were enrolled. The incidence and characteristics of CRE-BSI were explored in CRE-colonizers versus non-colonizers. Survival analysis was performed and risk factors for CRE-BSI and 30-day mortality were evaluated.

RESULTS

CRE-carriers were identified in 59/2465 (2.39%) neutropenic children and19/59 (32.2%) developed CRE-BSI, while 12/2406 (0.5%) of non-carriers developed CRE-BSI (P < 0.001). The 30-day survival probability was significantly lower in patients with CRE-BSI than in non-BSI (73.9% vs. 94.9%, P = 0.050). Moreover, the 30-day survival probability of patients with CRE-BSI was also poorer in CRE-carriers versus non-carriers (49.7% vs. 91.7%, P = 0.048). Tigecycline and amikacin exhibited satisfactory antimicrobial activity against all isolated strains. Fluoroquinolone sensitivity was lower in E. coli (26.3%) strains versus satisfactory susceptibility of E. cloacae and other CRE-strains (91.2%). CRE-BSI accompanying intestinal mucosal damage were independent risk factors for 30-day survival probability (both P < 0.05), while combined antibiotic therapy and longer duration of neutropenia were more prone to developed CRE-BSI (P < 0.05).

CONCLUSION

CRE-colonizers were prone to subsequent BSI and CRE-BSI was regarded as an independent predictor predisposing to high mortality in neutropenic children. Moreover, individualized antimicrobial therapy should be adopted due to different features of patients with separate CRE strains.

[Active screening of intestinal carbapenem-resistant Enterobacteriaceae in high-risk patients admitted to the hematology wards and its effect evaluation]

Objective: To evaluate the effect of intestinal carbapenem-resistant Enterobacteriaceae (CRE) active screening combined with enhanced intervention in the prevention and control of nosocomial infection in patients admitted to the hematological ward. Methods: Patients who were admitted to the Department of Hematology in a tertiary-care general hospital from March 1, 2017 to December 31, 2019 and underwent chemotherapy or immunosuppressive therapy comprised the intervention group. They were screened for intestinal CRE at least thrice. From December 1, 2016 to February 28, 2017, patients who underwent chemotherapy or immunosuppressive therapy without active intestinal CRE screening in the Department of Hematology formed the control group. Both the patient groups were monitored for CRE infection in real time. The χ(2) test was used to compare the changes in the CRE infection rate and mortality in high-risk patients before and after the active screening. Results: During the intervention period, the CRE colonization rate of patients was 16.46% (66/401) ; in terms of disease distribution, the colonization rate of acute leukemia was the highest 23.03% (26/113) . Of the 66 colonized patients, 27 (40.9%) patients were identified as positive for CRE at the first screening, 15 (22.7%) were identified at the time of the second screening, and the remaining 24 (36.4%) were identified at the third or subsequent screening; Carbapenem-resistant Klebsiella pneumoniae (CRPK) strains were dominant among the pathogens, accounting for 54.55% (36/66) . During the active screening period, the CRE infection rate (2.49%) and mortality rate (50.00%) of high-risk patients were significantly lower than those of the controls (11.30% and 69.23%, respectively) . The pathogens of 10 CRE infection patients during the intervention period were exactly the same as the previous active screening pathogens, and the coincidence rate was 100%. Conclusion: The CRE colonization rate was the highest in patients with acute leukemia who were admitted in the hematology wards. CRPK is the main pathogen of CRE colonization, infection, and death. Increasing the frequency of screening can significantly raise the positive rate of screening, Active screening can effectively reduce the incidence and subsequent mortality of CRE in high-risk patients admitted in the hematological wards. High coincidence rate between CRE screening positive pathogens and subsequent CRE infection pathogens. Intestinal CRE screening can serve as an indicator of CRE bloodstream infection in patients with hematological diseases as well as provide information for antibiotics therapy.

[A single-center study on the distribution and antibiotic resistance of pathogens causing bloodstream infection in adult patients with hematological disease during the period 2014-2018]

Objective: To investigate the distribution of pathogens and the antibiotic resistance profile of bloodstream infections in adult patients with hematological diseases in the period 2014-2018 to provide evidence for the rational use of antibiotics. Methods: We retrospectively analyzed the bloodstream infections in patients with hematological diseases from January 2014 to December 2018 at the institute of Hematology & Blood Diseases Hospital; this included an assessment of the clinical characteristics, distribution of pathogens, and antibiotic resistance data. Results: There were 1935 episodes of BSIs in the 1478 patients who were studied; among these, 1700 episodes occurred in the neutropenic phase. The 7-day and 30-day all-cause mortality rates were 5.5% and 8.2%, respectively. Bloodstream infection was usually accompanied by respiratory tract, perianal zone mucositis, and digestive tract symptoms; the respective proportions were 12.4%, 12.3%, and 9.1%, respectively. Total 2025 strains were isolated; 1551 (76.6%) of the pathogens were gram-negative bacteria, mainly Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa; 423 (20.9%) were gram-positive bacteria, mainly Staphylococcus spp. and Streptococcus spp. Viridans; 51 (2.5%) were fungi, mainly Candida tropicalis. The resistance rates of Enterobateriaceae to piperacillin/tazobactam, carbapenems, amikacin were <10%. The resistance rates of K. pneumoniae to cefepime, piperacillin/tazobactam and meropenem increased annually. The resistance rates of Pseudomonas aeruginosa to piperacillin/tazobactam, quinolones, Aminoglycosides were <5% even when compared to carbapenems. Eleven stains of methicillin-resistant S. aureus and 1 stain of vancomycin-resistant Enterococcus faecium were detected. Conclusion: The pathogens of bloodstream infection in adult patients with hematological diseases are widely distributed. The resistance rates of different strains vary; the rates in some species had a tendency to increase. Antibiotics should be selected rationally as per the distribution of pathogens and resistance to antibiotics in different patient groups.

[Analysis of pathogens and clinical characteristics of bloodstream infection in neutropenic children with hematological malignancies from 2014 to 2018]

Objective: To investigate the microbiologic and clinical characteristics of bloodstream infection in neutropenic pediatric patients with hematological malignancies and provide data support for the rational use of antimicrobial agents in these patients. Methods: A retrospective analysis was performed on the clinical data, pathogen species distribution, and drug sensitivity data of bloodstream infection in neutropenic pediatric patients with hematological malignancies from the Institute of Hematology & Blood Diseases Hospital from January 2014 to December 2018. Results: Total 537 episodes of bloodstream infections occurred in 427 neutropenic children with hematological malignancies; the 30-day all-cause mortality rate was 3.7%. The clinical feature of 44.7% patients with bloodstream infection was only fever, and the pathogenic bacteria were mainly enterobacteriaceae bacteria. Bloodstream infection was usually accompanied by oral mucosa (20.7%) , respiratory tract (20.5%) , and digestive tract (14.3%) symptoms. The distribution of pathogens in patients with different symptoms of bloodstream infection varied (χ(2)=40.561, P=0.001) . Total 550 strains of pathogens were isolated, and the top 5 bacteria were Streptococcus aureus (109 strains, 19.8%) , Escherichia coli (99 strains, 18.0%) , Staphylococcus epidermidis (75 strains, 13.6%) , Klebsiella pneumoniae (67 strains, 12.2%) , and Staphylococcus aureus (32 strains, 5.8%) . The resistance rates of Enterobacteriaceae and Pseudomonas aeruginosa to piperacillin/tazobactam and carbapenems were <5%. The proportion of methicillin-resistant Staphylococcus aureus (MRSA) in Staphylococcus aureus was 9.7%. Conclusion: The proportion of pathogenic bacteria gram-positive cocci and gram-negative bacilli in the bloodstream infection of neutropenic children with hematological malignancies was approximately the same, suggesting that the use of antimicrobial agents should be broad-spectrum. Carbapenems, glycopeptides, and enzyme inhibitor complexes still have good effects.