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OBJECTIVE To construct a risk prediction model for bloodstream infection （BSI） induced by carbapenem-resistant Klebsiella pneumoniae （CRKP）. METHODS Retrospective analysis was conducted for clinical data from 253 patients with BSI induced by K. pneumoniae in the First Hospital of Qinhuangdao from January 2019 to June 2022. Patients admitted from January 2019 to December 2021 were selected as the model group （n＝223）， and patients admitted from January 2022 to June 2022 were selected as the validation group （n＝30）. The model group was divided into the CRKP subgroup （n＝56） and the carbapenem- sensitive K. pneumoniae （CSKP） subgroup （n＝167） based on whether CRKP was detected or not. The univariate and multivariate Logistic analyses were performed on basic information such as gender， age and comorbid underlying diseases in two subgroups of patients； independent risk factors were screened for CRKP-induced BSI， and a risk prediction model was constructed. The established model was verified with patients in the validation group as the target. RESULTS Admissioning to intensive care unit （ICU）， use of immunosuppressants， empirical use of carbapenems and empirical use of antibiotics against Gram-positive coccus were independent risk factors of CRKP-induced BSI （ORs were 3.749， 3.074， 2.909， 9.419， 95%CIs were 1.639-8.572， 1.292- 7.312， 1.180-7.717， 2.877-30.840， P＜0.05）. Based on this， a risk prediction model was established with a P value of 0.365. The AUC of the receiver operating characteristic （ROC） curve of the model was 0.848 [95%CI （0.779， 0.916）， P＜0.001]， and the critical score was 6.5. In the validation group， the overall accuracy of the prediction under the model was 86.67%， and the AUC of ROC curve was 0.926 [95%CI （0.809， 1.000]， P＜0.001]. CONCLUSIONS Admission to ICU， use of immunosuppressants， empirical use of carbapenems and empirical use of antibiotics against Gram-positive coccus are independent risk factors of CRKP- induced BSI. The CRKP-induced BSI risk prediction model based on the above factors has good prediction accuracy.
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Objective To summarize current status of multidrug-resistant organism (MDRO) infection in lung transplant recipients and analyze the risk factors of MDRO infection. Methods Clinical data of 321 lung transplant recipients were retrospectively analyzed. According to the incidence of postoperative MDRO infection, they were divided into the MDRO group (n=122) and non-MDRO infection group (n=199). The incidence of MDRO infection in lung transplant recipients was summarized. The risk factors of MDRO infection in lung transplant recipients were analyzed by logistic regression model. The dose-response relationship between MDRO infection and time of ventilator use was determined by restricted cubic spline model. Results Among 321 lung transplant recipients, 122 cases developed MDRO infection, with an infection rate of 38.0%. Two hundred and twenty-nine strains of pathogenic bacteria were detected in the MDRO infection group, mainly Gram-negative bacteria (92.6%), and the top three strains were carbapenem-resistant acinetobacter baumannii (46.3%), carbapenem-resistant pseudomonas aeruginosa (22.3%) and carbapenem-resistant klebsiella pneumoniae (14.8%), respectively. MDRO infection mainly consisted of lower respiratory tract infection (61.5%), followed by ventilator-associated pneumonia (26.2%). Univariate analysis showed that the risk factors of MDRO infection in lung transplant recipients were single-lung transplantation, long-time postoperative use of extracorporeal membrane oxygenation (ECMO), long operation time, long-time urinary catheterization, long-time central venous catheterization and long-time ventilator use (all P < 0.05). Multivariate logistic regression analysis indicated that single-lung transplantation and long-time ventilator use were the independent risk factors for MDRO infection in lung transplant recipients (both P < 0.05). Results of restricted cubic spline model analysis showed that the risk of infection continued to increase with the prolongation of ventilator use time within 20 d. After 20 d, prolonging the time of ventilator use failed to increase the risk of infection, showing a plateau effect. Conclusions The MDRO infection rate tends to decline in lung transplant recipients year by year. Single-lung transplantation and long-time ventilator use are the independent risk factors for MDRO infection in lung transplant recipients.
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In recent years, the use of broad-spectrum antibiotics in clinical practice has led to an increase in the detection of Carbapenem-resistant Klebsiella pneumoniae(CrKP)in neonatal intensive care units.CrKP infection in newborns usually lacks specific clinical manifestations and can lead to bacteremia, meningitis and abdominal infections, which can be life-threatening.Combination of carbapenem antibiotics or newer drugs such as ceftazidime/avibactam, tigecycline and polymyxin are currently effective treatment options for CrKP infection in neonates.In addition to rational drug use, strict antimicrobial stewardship, hospital infection prevention and control measures are needed to reduce the colonisation and spread of CrKP in the neonatal ward.
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OBJECTIVE To analyze the efficacy and safety of polymyxin B in the treatment of carbapenem-resistant Klebsiella pneumoniae （CRKP）-bloodstream infection （BSI） in patients with hematologic malignancies. METHODS The medical records of patients with hematologic malignancies with CRKP-BSI who received polymyxin B for at least 3 days in our hospital from September 2019 to June 2021 were retrospectively analyzed. All patients were initially treated with a triple therapy namely polymyxin B+tigecycline+carbapenems for anti-infection therapy. RESULTS A total of 10 patients were enrolled as the study subjects. Eleven strains of CRKP were cultured in blood， including 10 strains of CRKP produced Klebsiella pneumoniae carbapenemase（KPC） and 1 strain of CRKP produced both KPC and metal-beta-lactamase； 9 strains were sensitive to colistin， 7 strains were sensitive to tigecycline， 5 strains were sensitive to amikacin and 2 strains were sensitive to compound sulfamethoxazole. All patients were accompanied by neutropenia， with an average duration of （14.1±6.4） days. They were all characterized by fever， chills and fatigue. After treatment， 6 patients were cured and discharged， 4 patients died of ineffective treatment of septic shock. No serious adverse events related to polymyxin B occurred in all patients. CONCLUSIONS Polymyxin B can be used as a therapeutic drug for CRKP-BSI in patients with hematological malignancies. No serious adverse event related to polymyxin B occurs during the treatment.
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Objective:To investigate the mechanism of polymyxin resistance related to lipopolysaccharide modification in carbapenem-resistant Klebsiella pneumoniae (CRKP). Methods:Plasmid-mediated drug resistance genes in seven CRKP strains were detected by conjugation assay and mcr gene detection. The expression of polymyxin resistance-related genes was measured using quantitative real-time PCR. The complete genomes of CRKP strains were sequenced. Silver staining and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were performed to analyze the changes in lipopolysaccharide (LPS). Results:The seven CRKP strains were negative for mcr genes and the results of conjugation assay were also negative. Moreover, no mobile genetic elements related to drug resistance were detected. Compared with wild-type strain, all seven CRKP strains that were resistant to polymyxin showed increased expression of pmrA, pmrB and pmrC genes at the transcriptional level; six showed increased expression of phoP/ phoQ genes; three showed decreased expression of crrA/ crrB genes; four showed decreased expression of mgrB gene. The missense mutation sites in drug-resistant strains were mainly in KPHS_09430, KPHS_35900, KPHS_39520 and KPHS_52420. IS Kpn14 insertion sequence was detected in CRKP-6 strain. MALDI-TOF-MS reveals the modification of natural lipid A with L-Ara4N in CRKP LPS. Conclusions:LPS modification induced by chromosome-mediated mutation in the two-component regulatory system was the main molecular mechanism of polymyxin resistance in CRKP isolates in this study. Effects of the mutation in the two-component system on polymyxin resistance varied in different strains.
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Carbapenem-resistant Klebsiella pneumoniae (CRKP) is highly prevalent and poses a great health challenge due to the lack of effective treatments. Klebsiella pneumoniae carbapenemase-2 (KPC-2), encoded by blaKPC-2 gene, is one of the major contributors to carbapenem resistance in CRKP. In China and other Asian regions, Tn1721 and plasmid IncFⅡ are the main vectors for blaKPC-2 transfer between Kpn ST11 strains, which lack clustered regularly interspaced short palindromic repeats (CRISPR) and restriction-modification (R-M) systems. The structure of transposons has a significant impact on the transposition frequency of blaKPC-2, which may be related to the different transposition patterns of transposons. The prevalence advantage of blaKPC-2 in Kpn ST11 strains is highly associated with the immune deficiency in Kpn ST11. By acquiring a re-engineered CRISPR-Cas3 system via conjugation, the high-risk IncFⅡ plasmid can be successfully cleaved and ST11 CRKP can regain antibiotic sensitivity, which provides a promising approach for clinical treatment and prevention of CRKP.
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Hypervirulent Klebsiella pneumoniae (HvKP) is a new variant of Klebsiella pneumoniae. It is characterized by strong virulence and easy dissemination. It mainly causes liver abscess with multiple invasive infections, including eye, lung and central nervous system, with a high fatality rate. A case of severe intracranial infection caused by HvKP was reported. The patient was a 44-year-old formerly healthy man. He had acute onset of fever, headache, and disturbance of consciousness, which rapidly progressed to intracranial hypertension and respiratory failure. Cerebrospinal fluid examination suggested purulent infection, and bacterial culture suggested Klebsiella pneumoniae, which was sensitive to other commonly used antibiotics except ampicillin. Brain magnetic resonance imaging showed multiple abnormal signals in bilateral frontal, parietal and temporal lobes, right centrum semiovale, bilateral corona radiata, basal ganglia, thalamus and insula, as well as enhancement of meningeal and ependymal membrane, and swelling of brain tissue. During hospitalization, the patient developed a blood stream infection of pan-drug-resistant Klebsiella pneumoniae and was in critical condition. After aggressive treatment, the patient was cured and discharged from the hospital. After half a year follow-up, his prognosis was good and his social function was restored. The clinical data, diagnosis and treatment of the patient were reported and the literature was reviewed to provide clinical reference for the disease.
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Objective:To investigate the clinical relationship between carbapenem-resis-tant Klebsiella pneumoniae (CRKP) infection and the severity of acute pancreatitis. Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 109 patients with acute pancreatitis who were admitted to Sir Run Run Shaw Hospital affiliated to Zhejiang University School of Medicine from January 2017 to January 2018 were collected. There were 66 males and 43 females, aged (48±17)years. Blood, body fluid or anal swab samples of patients were collected aseptically. Patients were treated with gallbladder puncture and drainage, nasobiliary drainage, surgical debridement, computed tomography (CT) guided interventional drainage or conservative treatment, respectively, after being comprehensively diagnosed. Observation indicators: (1) severity of acute pancreatitis and results of CRKP infection test; (2) diagnostic value of CRKP infection for severity of acute pancreatitis; (3) treatment of acute pancreatitis; (4) prognosis of patients. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test. Spearman correlation analysis were performed for correlation analyses. The receiver operating characteristic (ROC) curve was conducted to evaluate the diagnostic value. Results:(1) Severity of acute pancreatitis and results of CRKP infection test: of 109 patients, there were 37 cases with mild acute pancreatitis, 8 cases with moderate-severe acute pancreatitis, 64 cases with severe acute pancreatitis. There were 45 cases with mild disease and 64 cases with severe disease, 48 cases with CRKP infection and 61 cases without CRKP infection. There were 3 cases and 45 cases with CRKP infection in the 45 mild disease cases and 64 severe disease cases, respectively, showing a significant difference ( χ2=43.430, P<0.05). Result of Pearson correlation analysis showed that CRKP infection was positively correlated with the severity of acute pancreatitis ( r=0.631, P<0.05). The duration of hospital stay were (66±6)days and (24±3)days for the cases with CRKP infection and cases without CRKP infection, respectively, showing a significant difference ( t=47.661, P<0.05). (2) Diagnostic value of CRKP infection for severity of acute pancrea-titis: the area under the ROC curve, sensitivity, and specificity of CRKP infection for the diagnosis of SAP were 0.799 (95% confidence interval as 0.714?0.885, P<0.05), 0.688, and 0.911, respectively. (3) Treatment of acute pancreatitis: of 109 patients, 17 cases underwent nasobiliary drainage, 19 cases underwent gallbladder puncture and drainage, 42 cases underwent surgical debridement, 48 cases underwent CT guided interventional drainage and 43 cases underwent conservative treatment. One patient may undergo multiple treatments. Of 109 patients, 66 patients underwent one and more invasive treatments with 47 cases undergoing CRKP infection and 43 patients did not undergo invasive treatment with 1 case undergoing CRKP infection, respectively, showing a significant difference ( χ2=50.134, P<0.05). (4) Prognosis of patients: all 109 patients were followed up for 3?9 months, with a median follow-up time of 6 months. During the follow-up, there were 15 cases and 6 cases dead in the 48 cases with CRKP infection and the 61 cases without CRKP infection, respec-tively, showing a significant difference ( χ2=7.919, P<0.05). Conclusion:CRKP infec-tion is positively correlated with the severity of acute pancreatitis, and CRKP infection is associated with the duration of hospital stay and types of invasive treatments.
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Objective To evaluate the effect of donor-derived infection (DDI) on clinical prognosis of kidney transplant recipients. Methods Clinical data of 82 donors from donation after citizen's death and 148 kidney transplant recipients were retrospectively analyzed. According to the culture results of the lavage fluid of donor kidney, all recipients were divided into the lavage fluid culture of donor kidney positive group (positive group, n=92) and lavage fluid culture of donor kidney negative group (negative group, n=56). All recipients were assigned into the DDI group (n=19) and non-DDI group (n=129) according to whether they developed DDI or not. The distribution and composition ratio of positive strains in the lavage fluid of donor kidney were analyzed. The incidence of postoperative infection and other complications was assessed in the recipients. Perioperative conditions of the recipients were statistically compared between the DDI and non-DDI groups. The treatment efficacy and clinical prognosis of DDI recipients were evaluated. Results Among 148 recipients, 92 obtained positive culture results in the lavage fluid of donor kidney. A total of 131 pathogenic strains were isolated, including 41.2% (54/131) of Gram-positive cocci, 48.9% (64/131) of Gram-negative bacilli and 9.9%(13/131) of fungi. Among 148 recipients, 52 cases were infected. And 45% (41/92) and 20% (11/56) of the recipients were infected in the positive and negative group, respectively. Statistical significance was noted between two groups (P=0.002). Surgical site was the most common infection site in 52 infected recipients, followed by the urinary system. Nineteen recipients developed DDI with an incidence rate of 12.8% and fatality of 16%. Compared with the non-DDI recipients, DDI recipients had significantly higher graft loss rate and fatality, and longer postoperative hospital stay (all P < 0.05). Eight cases presented with carbapenem-resistant Klebsiella pneumoniae (CRKP) infection, after treatment with tigecycline and/or polymyxin and carbapenems, 3 cases died, and 3 underwent kidney graft resection. In the other 8 recipients with CRKP infection, 2 cases were treated with ceftazidime-avibactam (CAZ-AVI) alone, 3 treated with CAZ-AVI combined with carbapenems, and 3 initially treated with tigecycline combined with carbapenems followed by CAZ-AVI for salvage treatment. After corresponding treatment, the recipients achieved long-term survival. Conclusions DDI may lead to severe complications, while early specific antibacterial treatment plays a positive role.
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Objective To analyze the risk factors of multi-drug resistant organism (MDRO) infection after liver transplantation. Methods The clinical data of 77 recipients undergoing liver transplantation were retrospectively analyzed. According to the incidence of MDRO infection, all recipients were divided into the non-MDRO infection group (n=51) and MDRO infection group (n=26). The infection rate and strain distribution of MDRO in liver transplant recipients were summarized. The risk factors of MDRO infection in liver transplant recipients were identified. Clinical prognosis of all recipients was statistically compared between two groups. Results The infection rate of MDRO after liver transplantation was 34% (26/77), mainly carbapenem-resistant MDRO infection. The main sites of infection included lung, abdominal cavity and incision. Univariate analysis showed that postoperative tracheal intubation ≥48 h, length of intensive care unit (ICU) stay ≥72 h, length of hospital stay ≥30 d, re-operation, continuous renal replacement therapy (CRRT) and tacrolimus (Tac) blood concentration ≥15 ng/mL were the risk factors for MDRO infection after liver transplantation. Cox regression analysis indicated that postoperative tracheal intubation≥48 h, re-operation, CRRT and Tac blood concentration ≥15 ng/mL were the independent risk factors for MDRO infection after liver transplantation. The fatality in the MDRO infection group was significantly higher than that in the non-MDRO infection group [31%(8/26) vs. 10%(5/51), P=0.01]. Conclusions Postoperative tracheal intubation ≥48 h, re-operation, CRRT and Tac blood concentration ≥15 ng/mL may increase the risk of MDRO infection after liver transplantation and affect clinical prognosis of the recipients.
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Objective To investigate the distribution, drug resistance and molecular biological characteristics of carbapenem-resistant Klebsiella pneumoniae (CRKP) in our hospital, so as to provide reference for rational use of antibiotics and prevention and control of nosocomial CRKP infection. Methods Non-repetitive CRKP strains were collected from Jan. to Dec. 2019 in our hospital. VITEK 2 Compact automatic microbial analyzer and Kirby-Bauer test were used for bacterial identification and antimicrobial susceptibility analysis. WHONET 5.6 software was used to analyze CRKP detection rate, sample source and clinical department distribution. Hypermucoviscosity phenotype strains were screened by string test. Carbapenemase resistance genes, capsular serotype and virulence genes were detected by polymerase chain reaction (PCR). Results A total of 532 Klebsiella pneumoniae strains were detected, including 140 (26.3%) CRKP strains. The CRKP strains were mainly isolated from sputum and bronchoalveolar lavage fluid (66 strains, 47.1%), followed by urine (21 strains, 15.0%). The clinical departments of the isolates were mainly cardiovascular surgery intensive care unit (ICU) (47 strains, 33.6%), burn ICU (18 strains, 12.9%) and emergency department (18 strains, 12.9%). The antimicrobial susceptibility test showed that the CRKP strains were susceptible only to tigecycline, with resistance rates being over 50% to other common antibiotics. The resistance rates to the first to fourth generation cephalosporin antibiotics were above 85%, and the resistance rates to carbapenems were up to 100.0%. We also found that out of the 121 CRKP strains, 101 (83.5%) carried Klebsiella pneumoniae carbapenemase 2 (KPC-2) gene, seven (5.8%) with oxacillinase-48 (OXA-48) gene, and two (1.7%) with New Delhi metallo-β-lactmase 1 (NDM-1) gene; while one carried both KPC-2 and NDM-1 genes, and one carried both KPC-2 and OXA-48 genes; and nine carried no target drug-resistance genes. Fifteen (12.4%, 15/121) CRKP strains were positive for string test, with 13 being K64 capsular type and two being K47 capsular type; and 14 strains carried at least one virulence gene. Conclusion The clinical isolation rate of CRKP is high in our hospital, and the CRKP strains (mainly K64 capsular high virulence) are resistant to multiple antibiotics, suggesting that we should further strengthen the monitoring of drug resistance and rational use of antibiotics, so as to prevent the spread and prevalence of drug-resistant and highly virulent strains.
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Klebsiella pneumoniae (KP) is a common conditional pathogen, and also one of the common pathogens causing infection in immunocompromised patients, with its infection rate increasing year by year. Carbapenem antibiotics are effective drugs to control KP infection. But with the widespread use of carbapenem antibiotics, carbapenemresistant Klebsiella pneumoniae (CRKP) appears and increases year by year. Organ transplant recipients are at high risk of CRKP infection due to the suppressed immune system. Once drug-resistant bacteria infection occurs, it is often difficult to control and the survival rate of transplant organs is reduced, which brings great challenges to clinical treatment. In this article, the current status and treatment progress of CRKP infection in organ transplantation are summarized.
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Objective To summarize the clinical treatment experience of carbapenem-resistant Klebsiella pneumoniae (CRKP) infection after renal transplantation in donation after cardiac death (DCD) era. Methods Clinical data of 10 donors and 17 recipients with CRKP infection after DCD renal transplantation from January 2015 to January 2019 were retrospectively analyzed. Both donors and recipients received bacterial culture and drug sensitivity test. Clinical manifestations, treatment and outcome of CRKP-infected recipients were recorded. Results Seven donors were infected with CRKP. After pretreatment, CRKP in 2 cases turned negative, CRKP in 5 donors did not turn negative. All renal grafts were treated with tigecycline+meropenem+voriconazole lavage to prevent infection. Among 17 recipients with CRKP infection, 11 cases were positive for blood culture, 10 positive for urine culture, 3 positive for sputum culture, 3 positive for incisional secretion and 3 positive for retroperitoneal drainage. Clinical manifestations included fever in 8 cases, rupture and hemorrhage of the transplant renal artery in 7 cases or thrombosis in the transplant renal artery in 1 case, bladder irritation sign in 3 cases and cough with brick red jelly-like sputum in 1 case, respectively. Five patients were treated with tigecycline+meropenem, 1 patient suffered from renal graft loss and 4 recipients died. Twelve patients were treated with ceftazidime-avibactam +meropenem, 3 patients presented with renal graft loss and 1 recipient died. Conclusions CRKP-infected donor is not the absolute contraindication of renal transplantation. Pretreatment of donor infection and early administration of sufficient sensitive antibiotics can cure CRKP infection and improve the clinical prognosis of renal transplant recipients.
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ABSTRACT Polymyxin B is one of the last resort option for carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infection in China. Therefore, the timing of administration of polymyxin is frequently delayed. We collected 40 cases of CRKP bloodstream infections (BSIs) treated with combinations based on polymyxin B over 30 months. The primary outcome, 30-day mortality rate, was 52.5% (21/40). Early administration of polymyxin B is meant to administer the drug within 48 h of diagnosing bacteremia. Delayed administration was considered when polymyxin B was administered after 48 h of bacteremia onset. Polymyxin B duration and total dosages were similar in the two groups (11.57 days versus 11.76 days, p = 0.919; 1306.52 mg versus 1247.06 mg, p = 0.711). Compared with delayed administration, early use of polymyxin B-based combination therapy had a significant increase in the rate of bacterial clearance (65.22% versus 29.41%, p = 0.025; OR = 0.533) and decreased 30-day mortality (39.13% versus 70.59%, p = 0.045; OR = 0.461) and overall mortality (43.48% versus 82.35%, p = 0.022; OR = 0.321).
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Humans , Male , Female , Middle Aged , Polymyxin B/administration & dosage , Klebsiella Infections/drug therapy , Bacteremia/drug therapy , Carbapenem-Resistant Enterobacteriaceae/drug effects , Anti-Bacterial Agents/administration & dosage , Klebsiella Infections/mortality , Microbial Sensitivity Tests , Reproducibility of Results , Retrospective Studies , Treatment Outcome , Bacteremia/mortality , Kaplan-Meier EstimateABSTRACT
[Abstract] Objective To investigate the distribution and drug resistance of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates, so as to provide guidance for reasonable use of antibiotics. Methods Clinical CRKP isolates were collected in Changhai Hospital of Naval Medical University (Second Military Medical University) from Jan. 2014 to Dec. 2017, and the antimicrobial susceptibility test was carried out using automated instrument method and Kirby-Bauer method. The results were interpreted according to the standards of America Clinical and Laboratory Standards Institute (CLSI) or America Food and Drug Administration (FDA), and the data were analyzed by WHONET 5.6 software and SPSS 20.0 software. Results A total of 403 clinical CRKP isolates were collected, and 169 (41.9%) strains of CRKP were isolated from the specimens obtained from sputum/bronchoalveolar lavage fluid. The first isolation of CRKP was from different specimens, and there was a significant difference in the incidence of CRKP blood flow infection (P0.05). The top 3 departments in terms of isolation rates were Burn Intensive Care Unit (30.0%, 121/403), Digestive Department (8.4%, 34/403) and Emergence Intensive Care Unit (7.2%, 29/403). The antimicrobial susceptibility test showed that the drug resistance rate of the CRKP strains was more than 60.0% to all antibiotics, but tigecycline and fosfomycin. Conclusion The CRKP isolates are resistant to most commonly used antibiotics. It is necessary to strengthen the surveillance of drug resistance of CRKP isolates and take effective measures to control the spread of CRKP, especially in departments such as Burn Intensive Care Unit.
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Objective To explore the efficacy of meropenem in the treatment of neonatal carbapenem-resistant Klebsiella pneumoniae (CRKP) sepsis and its influencing factors, so as to provide reference for reasonable use of antibiotics in clinic. Methods A total of 27 neonates who were diagnosed as CRKP sepsis in Shanghai Children’s Hospital from Jun. 2014 to Jun. 2018 were included in this retrospective study. The clinical efficacy of meropenem was evaluated and the patients were divided into two groups: meropenem monotherapy effective group and meropenem monotherapy ineffective group who required other antibiotics for combination therapy. The perinatal factors, prior exposure to carbapenems and other clinical characteristics were compared between the two groups. Results The effective rate of meropenem monotherapy in treating neonatal CRKP sepsis was 48.1% (13/27), and the overall effective rate was 74.1% (20/27) when another antibiotic was added. The incidences of open wound after surgery (7/14 vs 1/13), septic shock (7/14 vs 1/13), positive culture of sterile coelomic fluid (6/14 vs 0/13), and invasive mechanical ventilation (10/14 vs 1/13) were higher in meropenem monotherapy ineffective group than in meropenem monotherapy effective group (all P0.05), and the diameter of CRKP inhibition zone in meropenem monotherapy ineffective group was smaller than that in meropenem monotherapy effective group ( [9.14±3.37] mm vs [12.85±5.27] mm, P0.05). Conclusion Meropenem monotherapy is effective for treatment of neonatal CRKP sepsis. Other antibiotics are recommended when the patients also have open wound after surgery, septic shock, positive culture of sterile coelomic fluid, invasive mechanical ventilation, or smaller inhibition zone of CRKP on meropenem.
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Objective To evaluate the efficacy and safety of different antimicrobial regimens in patients with bloodstream infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP).Methods The clinical date of patients with CRKP bloodstream infections were retrospectively analyzed at the First Affiliated Hospital of Zhejiang University Medical College between January 2017 and January 2018.All subjects were separated into three groups based on antibiotics regimens over 72 hours,including meropenem 2.0 g every 8 hours,tigecycline 200 mg as initial dose and 100 mg every 12 hours,and polymyxin B 1.25 mg/kg every 12 hours as salvage treatment of tigecycline.Results A total of 86 patients were finally recruited,including 14,52 and 20 patients in groups of meropenem,tigecycline and polymyxin B salvage,respectively.All of the strains were resistant to meropenem and susceptible to tigecycline and polymyxin B initially,while 2 of them became resistant to tigecycline during treatment.The 28-day mortality was significantly higher in meropenem group (13/14) than that in tigecycline group and polymyxin B salvage group (61.5％,32/52) and (12/20),respectively (P＜0.01),while as no significant difference was seen in the last two groups (x2=0.014,P＞0.05).The incidences of hepatic impairment [3.8％(2/52) vs.1/20] and renal dysfunction (0 vs.1/20) between tigecycline group and polymyxin B salvage group were both comparable (P＞0.05).Conclusion The meropenem-based therapy is not recommended for CRKP-related bloodstream infections.Tigecycline-based therapy is still disappointing despite salvage use of polymyxin B after 72 hours.Hepatic and nephretic toxicities caused by additional polymyxin B are acceptable.
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Objective To screen specific mass peaks (SMP) of carbapenem-resistant Klebsiella pneumoniae (CRKP) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and perform rapid homology analysis on CRKP based on SMP.Methods 76 strains of CRKP with multilocus sequence typing (MLST) were selected from a microbiology laboratory of a hospital, 52 strains were for establishment of method and 24 strains were for validation of method. Five different criteria for selecting SMP of CRKP were set, SMP of different ST-type were screened according to different criteria, CRKP was typed based on screened SMP, criterion with the highest coincidence rate of MLST results was determined as the best criterion. Twenty-four CRKP strains were typed according to the specific peaks screened through best criteria, accuracy of SMP typing method was verified, and was compared with principal component analysis (PCA) and main spectra profile (MSP) cluster analysis in mass spectrometer software.Results According to standard 2 (①signal-to-noise ratio [S/N]≥4, ②S/N ratio≥1.5, ③coefficient of variability [CV≤40％]), 45 SMP were selected from 52 strains of CRKP strains, 29 strains of CRKP were typed by SMP, with the highest coincidence rate (82.8％) with MLST, which was determined as the best criterion. Another 24 CRKP strains were typed according to SMP screened based on this criterion, and the coincidence rate with MLST was 83.3％. The coincidence rate between PCA cluster analysis and MLST was only 66.7％, consistency between MSP clustering analysis and MLST was poor, and it didn't conform to the grouping trend of ST typing.Conclusion MALDI-TOF MS can select SMP of CRKP of different ST, which can be used for rapid homology analysis on CRKP, provide basis for surveillance and control of outbreak of healthcare-associated infection.
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Objective To investigate and control the outbreak of infection caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) in a gastroenterology intensive care unit (ICU), so as to provide reference for the prevention and control of clinical multidrug-resistant organisms (MDROs).Methods Epidemiological investigation was conducted on 3 patients with CRKP infection in a gastroenterology ICU on January 21-31, 2018, specimens were collected with environmental biology monitoring method, CRKP in environment was searched, homology between patients and environmental isolates were analyzed by pulsed-field gel electrophoresis (PFGE).Results Three patients were all isolated CRKP from sputum and blood specimens, all were male, with adjacent beds in the same ward, and treated by the same doctor.The number of isolated CRKP and infection rate in January 2018 were higher than those in other months, infection rate was significantly different (χ2=13.67, P＜0.01).A total of 102 environmental specimens were collected, including air and surface of objects, only 1 of which (nurse's uniform) was isolated 1 strain of KP.PFGE typing of KP isolated from patients and environment showed that there were two genotypes A and B, KP isolated from uniform of a nurse, hydrops abdominis and blood specimen of patient at bed 07, blood specimen of patient at bed 08, as well as sputum and blood specimen of patient at bed 09 were all type A, KP isolated from sputum specimen of patient at bed 07 was type B, KP isolated from hydrops abdominis in patient at bed 09 was not be typed.After comprehensive intervention, CRKP was not no longer isolated from 3 patients, and there was no new case in the ward.Conclusion Imperfect implementation of prevention and control measures for MDROs by health care workers may be an important cause for the spread of CRKP.
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Objective To explore the drug-resistant genotypes and homology of carbapenem-resistant Klebsiella pneumoniae (CRKP).Methods 38 strains of clinically isolated CRKB in a hospital between September 2015 and February 2016 were collected,drug resistance genes were detected with polymerase chain reaction (PCR),homology of strains was analyzed with pulsed-field gel electrophoresis (PFGE).Results All 38 strains were from intensive care unit(ICU) and surgical intensive care unit(SICU),accounting for 39.48％ and 34.21 ％ respectively.38 strains all harboured drug resistance genes blaKPC and blaSHV,6 strains harboured blaCTT.PFGE revealed that strains were divided into types A,B,C,and D,type C was predominant(65.78％,25/38).Of type A strains,strains 14,15,and 16 carried drug resistance genes blaKPC 2,blaSHV,and blaCTT-M-15 respectively,these strains were all isolated from SICU patients,strains 14 and 15 were isolated on the same day,strain 16 was isolated on the following week;of type C strains,homology of strain 10,18,25,and 28 was 100％.strian 10 and 18 were isolated from ICU patients,strains 25 and 28 were isolated from patients in division I of neurology ICU(both were transferred from ICU),and both were isolated during patient hospitalization in ICU,the isolation time only differed for one day.Conclusion The main drugresistant genotypes of CRKB in this hospital are mainly blaKPC and blaSHV,there is epidemic of clone strains in this hospital.