ObjectiveTo study the distributions of virulence genes of Klebsiella pneumoniae (KP) and the distribution of hypervirulent KP (HvKP), and assess the performance of a single gene to predict HvKP.MethodsPolymerase chain reaction (PCR) method was used to analyze 12 virulence-related genes (entB, irp2, iroN, iucA, mrkD, fimH, c-rmpA, p-rmpA2, p-rmpA, wzy-K1, allS and peg-344) and drug-resistance gene blaKPC among 376 clinical KP strains collected from January 2016 to December 2018. Sequence types (ST) of KP were determined after sequencing and comparison, following the detection of 7 house-keeping genes (gapA, infB, mdh, pgi, phoE, rpoB and tonB) by PCR method. Statistical analyses were made for the distributions of virulence genes of KP and the distribution of HvKP with GraphPad Prism 8 software.ResultsAmong the 376 KP strains, the positive rates of entB, irp2, iroN, iucA, mrkD, fimH, c-rmpA, p-rmpA2, p-rmpA, wzy-K1, allS and peg-344 were 100.0%, 76.9%, 22.1%, 28.2%, 97.6%, 97.1%, 1.6%, 24.5%, 21.0%, 7.4%, 4.8% and 31.6%, respectively. The positive rates of the aforementioned virulence genes in the blaKPC-positive group (n=167) were 100.0%, 94.0%, 7.2%, 16.8%, 97.0%, 96.4%, 0.0%, 15.0%, 6.6%, 0.0%, 0.0% and 21.0%, respectively, and those in the blaKPC-negative group (n=209) were 100.0%, 63.2%, 34.0%, 37.3%, 98.1%, 97.6%, 2.9%, 32.1%, 32.5%, 13.4%, 8.6% and 40.2%, respectively; there was no statistically significant difference in entB, mrkD or fimH between the two groups (P>0.05), the positive rate of irp2 was higher in the blaKPC-positive group than that in the blaKPC-negative group (P<0.05), and the positive rates of the rest virulence-related genes were lower in the blaKPC-positive group than those in the blaKPC-negative group (P<0.05). The rate of HvKP in the blaKPC-negative group was higher than that in the blaKPC-positive group (38.3% vs. 18.0%, P<0.05). As a marker of HvKP, iucA showed high sensitivity and specificity (90.9% and 97.7%), followed by p-rmpA2 (83.6% and 100.0%) and iroN (73.6% and 99.2%). ST11 accounted for 87.4% in the blaKPC-positive group, while ST23, ST20, ST54 and ST29 were the four primary types in the blaKPC-negative group, accounting for 23.4% totally.ConclusionsDifferent virulence genes mean different distributions in KP. blaKPC-negative KP is more virulent than blaKPC-positive KP. iucA and p-rmpA2 could serve as good predicators of HvKP. Armed with extreme virulence and drug-resistance, blaKPC-positive HvKP is of great clinical concern.
ObjectivesTo identify the clinical characteristics and prognosis for CRKP (Carbapenem-resistant Klebsiella pneumonia, CRKP) infection among ICU patients in the Second Affiliated Hospital of Anhui Medical University. MethodsWe conducted a retrospectively analysis in which 19 patients infected by CRKP with another 21 CSKP (Carbapenem-sensitive Klebsiella pneumoniae, CSKP) infected patients from January 2017 to April 2018. Risk factors for CRKP infection were assessed. ResultsThe lower respiratory tract is the most common site of CRKP infection in our department. CRKP infection was associated with several clinical symptoms, particularly a higher incidence of sepsis shock (χ2=8.338, P=0.004), more application of the combined medicine (χ2=26.3, P<0.001), prolonged hospital stays (χ2=–2.217, P=0.027) and more expenses on antibiotics (χ2=12.855, P=0.005), and the declined survival rates in 14 days (χ2=4.269, P=0.039) and 21 days (χ2 =5.647, P=0.017). The resistance rate of CRKP strains was high, however no resistance to tegafycline was found. The risk factors of CRKP infection included three generations of cephalosporin and/or hydrocarbonase antibiotics exposure (χ2 =6.388, P=0.041), exposure time of three generations of cephalosporin (U=–2.187, P=0.029), exposure time of hydrocarbonase antibiotics (U=–2.103, P=0.035), tracheal intubation (χ2=6.352, P=0.012), tracheotomy (χ2 =4.821, P=0.028), SOFA score (t=4.505, P<0.001) and Charlson comorbidity index (t=3.041, P=0.004). The SOFA score was the only factor independently associated with CRKP bacteremia (P=0.02). ConclusionsCRKP infections in ICU directly affect the course of disease, survival time and treatment expenses of patients. Therefore, monitoring bacterial resistance, rational use of antibiotics, and protection of the immune function are of great significance for prevention and treatment of CRKP infection.
Objective
To investigate the clinical characteristics and bacterial drug resistance of bloodstream infection of gram-negative bacteria, and provide guidance for clinical rational drug use and control of hospital infection.
Methods
A retrospective analysis was conducted in the patients diagnosed as severe pneumonia with blood culture of gram-negative bacteria from January 2015 to December 2017 in Beijing Anzhen Hospital.
Results
A total of 60 severe pneumonia patients suffered from bloodstream infection of gram-negative bacteria were recruited including 34 males and 26 females aging from 42 to 89 years and 73.4 years in average. In the 60 patients, 32 cases were infected with Klebsiella pneumonias, 20 cases were infected with Acinetobacter baumanni, and 8 cases were infected with Escherichia coli. The antimicrobial susceptibility testing result of Klebsiella pneumonias showed that the drug susceptibility rate was 100% to tigecycline, and 6.3% to amikacin. Escherichia coli was sensitive to Amikacin, imipenem, ceftazidime and meropenem while resistance to other drugs. The antimicrobial resistance of Acinetobacter baumanni was 28.6% for cefoperazone/sulbactam, and 14.3% for tigecycline. C-reactive protein, procalcitonin and SOFA scores were higher in the patients infected with Acinetobacter baumanni. Neutrophils and blood lactic acid were higher in the patients infected with Klebsiella pneumonias. There were no statistical differences in white blood cell, platelet or motality rate between the patients infected with Acinetobacter baumanni and the patients infected with Klebsiella pneumonias. SOFA scores and blood lactic acid had significantly statistical relevance with prognosis.
Conclusion
There is a high proportion of drug resistance of Klebsiella pneumoniae and Acinetobacter baumanni in the bloodstream infection of gram-negative bacteria.
ObjectiveTo observe and analyze the clinical features and prognosis of endogenous klebsiella pneumoniae endophthalmitis (EKPE).MethodsThis is a retrospective case series study. Seven patients (8 eyes) with EKPE were enrolled in this study. There were 3 males (4 eyes) and 4 females (4 eyes). The ages were from 39 to 76 years, the mean age was 57.29 years. All these cases had no history of trauma and surgery. Meanwhile, they all had some risk factors, such as infection, diabetes mellitus, systemic lupus erythematosus, liver abscess, renal insufficiency undergoing dialysis treatment, Hodgkin lymphoma and so on. All the eyes were undertaken visual acuity, slit lamp and fundus examination to observe the eye conditions. Seven eyes were undertaken pars plana vitrectomy with intravitreal injection of antibiotics from 2 days to 2 weeks after onset. And only one eye was undertaken intravitreal injection of antibiotics without surgery. Microbial stains and culture were performed for 7 eyes using vitreous and aqueous fluid samples from the procedures of vitrectomy. Meanwhile, culture and drug sensitive tests were performed from blood samples. According to the result of the drug sensitive tests, carbapenems such as imipenem and meropenem were used in each patient through intravenous injection from 1 to 2 weeks. During the follow up period from 3 days to 1 year, prognosis was observed at each office visit.ResultsFrom these eight eyes, presenting visual acuity was light perception (4 eyes), hand motion (3 eyes), 0.1 (1 eye). Hypopyon (6 eyes), aqueous fluid opacity (2 eyes) and diffuse vitreous opacity (8 eyes) were found. Changes in fundus like optic disc, macular edema and retinal vascular occlusion could be observed. Cultures of the vitreous and aqueous fluid samples from vitrectomy were all point out to klebsiella pneumoniae. At last office visit, the visual acuity of patients with hypopyon was no light perception (1 eye), light perception (1 eye), hand motion (1 eye). The visual acuity of patients without hypopyon was 0.05 (1 eye) and 0.5(1 eye). Finally, 1 eye was underwent enucleation and one patient with binocular disease was died of multiple organ failure.ConclusionsEKPE is almost unilateral attacked. Changes in fundus like optic disc, macular edema and retinal vascular occlusion can be observed. EKPE is commonly associated with poor visual outcomes. It is useful to save patients’ visual acuity by performing vitrectomy before hypopyon happened.
ObjectiveTo evaluate the relationship between the genes involved in regulating iron uptake and maintaining iron homeostasis in Klebsiella pneumoniae from different sources and pathogenicity.MethodsThe genomic DNA sequences of two strains of Klebsiella pneumoniae from different sources were sequenced, stitched together, annotated and analyzed by second generation sequencing technique. The transversal comparison between different types of Klebsiella pneumoniae in NCBI database of iron carrier gene cluster iroB/C/D.ResultsIn these two Klebsiella pneumoniae clinical strains, the strain isolated from liver abscess patient carried 11 different iron acquisition and transportation system specific genes, which were not found in the non-liver abscess patient strain. Combined with the analysis of this sequence, in the NCBI database, six different strains of Klebsiella pneumoniae showed iroB/C/D triple positive.ConclusionIron acquisition and transportation system in Klebsiella pneumoniae may be an important pathogenic factor, which is closely related to hepatic abscess.
ObjectiveTo understand the clinical distribution and drug resistance of Klebsiella pneumoniae in Yibin during 2011 to 2014 so as to provide evidence for clinical rational use of antimicrobial drugs.
MethodsKlebsiella pneumoniae isolated from all types of clinical specimens were collected from the First People's Hospital and the Second People's Hospital of Yibin during 2011 to 2014. VITEK2 Compact and its supporting identification card GP and drug sensitivity test card AST-GP67 were used for detection, and the results were analyzed and summarized.
ResultsMost Klebsiella pneumoniae were detected from the Department of Respiratory Medicine, the proportion for each year was 48.15%, 46.24%, 45.44%, and 44.97% during 2011 to 2014. Klebsiella pneumoniae isolated were mainly from sputum samples, the proportion for each year was 81.01%, 89.18%, 87.80%, and 83.52% between 2011 and 2014. Imipenem and piperacillin/tazobactam resistance rates were lower, but the overall trend was rising. Ampicillin/sulbactam, and sulfamethoxazole resistance rates were higher. Levofloxacin, ciprofloxacin increased year by year. Aztreonam, cefepime, and amikacin rate declined.
ConclusionKlebsiella pneumoniae is one of the main infection pathogen in the Department of Respiratory Medicine. Klebsiella pneumoniae resistance rates are higher. Klebsiella pneumoniae were sensitive to enzyme inhibitors β-lactam antimicrobial agents and carbapenem antibiotics.
Objective To investigate the risk factors for Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections, and construct a clinical model for predicting the risk of CRKP infections. Methods A retrospective analysis was performed on Klebsiella pneumoniae infection patients hospitalized in the Third Hospital of Hebei Medical University from May 2020 to May 2021. The patients were divided into a CRKP group (117 cases) and a Carbapenem-sensitive Klebsiella pneumoniae (CSKP) group (191 cases). The predictors were screened by full subset regression using R software (version 4.3.1). The truncation values of continuous data were determined by Youden index. Nomogram and score table model for CRKP infections risk prediction was constructed based on binary logistic regression. The receiver operator characteristic (ROC) curve and area under curve (AUC) were used to evaluate the accuracy of models. Calibration curve and decision curve were used to evaluate the performance of models. Results308 patients with Klebsiella pneumoniae infections were included. A total of 8 predictors were selected by using full subset regression and truncation values were determined according to Youden index: intensive care unit (ICU) stay at time of infection>2 days, male, acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score>15 points, hospitalization stay at time of infection>10 days, any history of Gram-negative bacteria infection in the last 6 months, heart disease, lung infection, antibiotic exposure history in the last 6 months. The AUC of CRKP prediction risk curve model was 0.811 (95%CI 0.761 - 0.860). When the optimal cut-off value of the constructed CRKP prediction risk rating table was 6 points, the AUC was 0.723 (95%CI 0.672 - 0.774). The Bootstrap method was used for internal repeated sampling for 1000 times for verification. The model calibration curve and Hosmer-Lemeshow test (P=0.618) showed that these models have good calibration degree. The decision curve showed that these models have good clinical effectiveness. Conclusion The prediction model of CRKP infections based on the above 8 risk factors can be used as a risk prediction tool for clinical identification of CRKP infections.
目的 探討高毒力肺炎克雷伯菌（hypervirulent Klebsilla pneumoniae，hvKP）感染患者的臨床特征、診斷方法和治療過程，提高臨床醫生對 hvKP的認識。方法 回顧性分析1例hvKP感染患者的一般資料、影像學表現和治療方案，并進行相關文獻復習。結果 患者男，52歲，因發熱1+個月入院，入院CT提示：左肺下葉外基底段胸膜下占位伴雙肺散在多發結節，周圍型肺癌伴轉移？炎性？肝S6-7段占位，肝膿腫？痰及肝膿液培養均發現肺炎克雷伯菌，二代測序示肺炎克雷伯菌，故考慮為hvKP感染。根據藥敏結果先后調整抗生素為美羅培南（1.0 g 2次/d）聯合頭孢他啶（3.0 g 2次/d）、左氧氟沙星（0.5 g 1次/d）聯合頭孢他啶（3.0 g 2次/d）、頭孢哌酮鈉舒巴坦鈉聯合阿米卡星治療，并予引流肝膿腫及胸腔積液后，患者癥狀、體征和影像學異常均明顯好轉，隨訪復查，病灶基本吸收。結論 肺炎克雷伯菌肝膿腫合并膿毒性肺栓塞患者，影像表現疑似肺癌伴肺內轉移。針對該類患者，臨床醫生應考慮肺炎克雷伯菌感染可能，盡早獲取病原學證據，同時關注hvKP常見的侵襲部位，結合藥敏試驗及抗生素藥效學/藥代動力學特點，選用合適的抗生素，從而改善疾病預后。
Objective To compare the screening ability of modified Hodge test (MHT), modified carbapenem inactivation method (mCIM) and EDTA-carbapenem inactivation method (eCIM) for drug resistance phenotype of carbapenemase-producing Klebsiella pneumoniae. MethodsCarbapenem resistant Klebsiella pneumoniae (CRKP) strains clinically isolated from 5 hospitals in Chengdu between January 2019 and December 2021 were collected, and the carbapenem sensitive Klebsiella pneumoniae (CSKP) strains isolated in the same period were randomly collected. Polymerase chain reaction (PCR) -amplified carbapenem resistance gene as the gold standard, the consistencies between the results of the three phenotypic tests and the results of genetic testing were compared. Results A total of 160 CRKP strains and 120 CSKP strains were isolated. Among the 160 CRKP strains, carbapenem resistance genes were detected in 156 strains, including 105 strains of blaKPC-2, 41 strains of blaNDM-1, 8 strains of blaKPC-19, 1 strain of blaIMP-1, and 1 strain carrying both blaKPC-2 and blaNDM-1. None of the 120 CSKP drug resistance genes were detected. The sensitivity and specificity of carbapenem screening for MHT and mCIM were 73.08% (114/156), 96.67% (116/120), 97.44% (152/156) and 98.33% (118/120), respectively. The sensitivity and specificity of eCIM for screening metalloenzymes were 95.35% (41/43) and 100% (120/120), respectively. Conclusions The sensitivity of MHT to detect carbapenemase is lower than that of the other two methods, and it is easy to produce false negatives when it is used to detect metalloenzymes. The mCIM has high sensitivity and is consistent with the PCR genetic test results. The combined detection of mCIM and eCIM can screen carbapenemases more effectively and distinguish the types of carbapenemases.
Objective
To explore the clinical manifestations, computed tomography features, management and prognosis of Klebsiella pneumoniae liver abscess complicated with septic pulmonary embolism.
Methods
The clinical data of patients with Klebsiella pneumoniae liver abscess complicated with septic pulmonary embolism admitted to Dongnan Hospital of Xiamen University from January 2012 to January 2017 were retrospectively analyzed.
Results
There were 8 patients who had Klebsiella pneumoniae liver abscess complicated with septic pulmonary embolism. Fever occurred in all patients, respiratory symptoms were noted in 5 patients, abdominal pain occurred in 2 patients, endophthalmitis coexisted in 1 patient, and diabetes mellitus coexisted in 7 patients, with no chest pain or hemoptysis. In biochemical indexes, procalcitonin increased most obviously. Microbiological studies revealed Klebsiella pneumoniae in 8 patients. Chest CT showed peripheral nodules with or without cavities, peripheral wedge-shaped opacities, a feeding vessel sign, pleural effusion, and infiltrative shadow. One patient finally deteriorated to acute respiratory failure, and died due to acute respiratory distress syndrome and/or septic shock. There was one case of spontaneous discharge. A total of 6 patients were improved and cured.
Conclusions
The clinical manifestation of Klebsiella pneumoniae liver abscess complicated with septic pulmonary embolism is unspecific and misdiagnosis rate is relatively high. The major characteristics of chest CT scan include peripheral nodules with or without cavities, peripheral wedge-shaped opacities and a feeding vessel sign. Diagnosis and differential diagnosis can be made based on these features combined with clinical data and primary disease (liver abscess).
