Hypervirulent Klebsiella pneumoniae has the characteristics of high virulence and high viscosity, which can cause pneumonia, bacteremia, liver abscess, meningitis and other diseases, and in severe cases, it can be life-threatening. At present, studies on the pathogenic mechanism of hypervirulent Klebsiella pneumoniae showed that siderophore virulence genes play an important role in it. The siderophores closely related to hypervirulent Klebsiella pneumoniae virulence mainly include aerobactin, enterobactin, yersiniabactin and salmochelin. Siderophore-related virulence genes mainly include aer, iucB, iroNB and kfuBC. This article focuses on a brief review of the role of siderophore virulence genes in the pathogenic mechanism of hypervirulent Klebsiella pneumoniae, and aims to guide infection control.
Objective To explore the colonization of Klebsiella pneumoniae in the intensive care unit of our hospital and analyze the risk factors. Methods A total of 226 patients were actively screened in the surgical intensive care unit and neurosurgery intensive care unit from June to December 2020 in the hospital, and their clinical data were retrospectively analyzed. Results Totally, 87 strains of Klebsiella pneumoniae were screened out, 69 strains were carbapenem-resistant Klebsiella pneumoniae (CRKP), and the resistant genotype was mainly KPC genotype (79.6%). The resistance rates of meropenem were 75.0% and 77.4%, respectively. Age and pulmonary infection before admission are risk factors for CRKP colonization, while pulmonary infection before admission is an independent risk factor for CRKP colonization. Conclusions Both the CRKP colonization rate of patients and the rate of resistance to carbapenem antimicrobials are relatively high in the intensive care unit of our hospital. Pulmonary infection before admission is an independent risk factor for CRKP colonization.
In recent years, with the wide application of carbapenems, the resistance of Enterobacterium to carbapenems has become increasingly high, leading to a large number of carbapenem-resistant Klebsiella pneumoniae (CRKP). These bacteria are often resistant to many different types of antibacterial drugs, including carbapenems, which leads to clinical treatment failure and seriously threatens the life safety of patients. Currently, these bacteria have become an independent risk factor for patients’ death. This article reviews the drug resistance, infection status and influencing factors, and medication therapy of CRKP, in order to facilitate the clinical diagnosis, treatment, and disease process control of CRKP infection, and provide reference for curbing bacterial drug resistance.
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).
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.
ObjectiveTo analyze clinical features and treatment of cases of perineum necrotizing fasciitis with diabetes.MethodsThe clinical data of 48 cases of perineum necrotizing fasciitis with diabetes were retrospectively collected in the Affiliated Hospital of Chengdu University of Traditional Chinese Medicine from 2013 to 2017. The clinical features, bacterial culture results, and laboratory indicators such as the white blood cell count (WBC), platelet (PLT), C reactive protein (CRP), serum sodium (Na+), potassium (K+), calcium (Ca2+), and blood sugar (Glu) levels were compared between the diabetic patients and the non-diabetic patients and between the death and the survival.ResultsAmong the 48 cases, there were 29 cases of perineum necrotizing fasciitis with diabetes, 10 cases of death, 36 cases of positive results of bacterial culture. ① Between the diabetic patients and the non-diabetic patients, the proportions of the gender, surgery within 24 h, staying the ICU, and death had no significant differences (P>0.05); the age, time from onset to admission, and staying time in the ICU had no significant differences too (P>0.05). The Klebsiella infection rate in the diabetic patients was significantly higher than that in the non-diabetic patients (P<0.05). There were no significant differences in the CRP, WBC, PLT, Ca2+, Na+, and K+ levels between the diabetic patients and the non-diabetic patients on the 1st, the 3rd, and the 7th day of the admission (P>0.05). ② The proportions of the gender and surgery within 24 h had no significant differences (P>0.05), but of staying the ICU had a significant difference (P<0.05) between the death and the survival; the age, the time from onset to admission, and staying time in the ICU had no significant differences (P>0.05). The positive rate of bacterial culture results had no significant difference between the death and the survival (P>0.05). Except for the PLT (P<0.05), there were no significant differences in the CRP, WBC, and Glu levels between the death and the survival on the 1st and 3rd day of the admission (P>0.05).ConclusionsEarly diagnosis, early operation, and multidisciplinary treatment are important in treatment of perineum necrotizing fasciitis. Antibiotics which are sensitive to Klebsiella when treated with early experimental use should be considered for patients with diabetes mellitus.
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.
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.
Objective To analyze the current drug resistance and risk factors of hospital acquired pneumonia( HAP) due to extended spectrumβ-lactamase ( ESBLs) producing Escherichia coli and Klebsiella pneumoniae, and to estimate the prevalence trend of ESBLs producing strains. Methods FromApril 2007 to January 2008, 140 patients of Xinhua Hospital with HAP due to E. coli and K. pnermoniae were enrolled.Among them, 88 patients were with ESBLs producing strains and 52 patients were with non-ESBLs producing strains. Risk factors were analyzed by comparing between these patients. The rate of drug resistance was determined by antibiotic sensitive test. Fifty-three ESBLs producing strains were genotyped by random amplified polymorphic DNA ( RAPD) . Results The rate of drug resistance of ESBLs producing strains washigher than that of non-ESBLs producing strains. ICU stay, use of third- and forth-generation cehpalosporin were found to be the independent risk factors by multivariate analysis with logistic regression. By RAPD, 37 ESBLs producing E. coli strains were divided into 27 types and 16 ESBLs producing K. pneumoniae strains were divided into 13 types. Conclusions ICU stay, use of third-generation and forth-generation cehpalosporin remain as major risk factors in the HAP due to ESBLs producing E. coli and K. pneumoniae.RAPD is an economic, quick and credible method for epidemic analysis
Objective To investigate the clinical characteristics and drug resistance changes of nosocomial infection caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) in different types of clinical departments, and to provide evidence for prevention and control of CRKP infection. Methods The hospital infection real-time monitoring system was used to retrospectively collect the inpatients with CRKP nosocomial infection in the First People’s Hospital of Lianyungang from January 2019 to December 2023 as the research objects. According to the different sources of departments, they were divided into intensive care unit (ICU) group, internal medicine group and surgery group. The changes of clinical characteristics and drug resistance to common antibiotics were analyzed. Results A total of 636188 inpatients were monitored, and 225 cases were infected with CRKP, with an overall infection detection rate of 0.035%. The detection rates of CRKP infection in the ICU group, internal medicine group, and surgery group were 0.736% (138/18749), 0.013% (44/336777), and 0.015% (43/280662), respectively, with the ICU group demonstrating a significantly higher rate than the other groups (P<0.05). The detection rates fluctuated in the early stage and then decreased rapidly in different years. The main infection site of CRKP in all groups was lower respiratory tract, but the proportion of device-related infections in the ICU group was higher than that in the internal medicine and surgery groups (P<0.05). In terms of the infected population, there was no significant difference in gender among groups (P>0.05) with the proportion of males more than 60%, while the difference in the proportion of patients aged ≥65 years among groups was statistically significant (P<0.05), with the highest in the internal medicine group (86.36%). The burden of underlying diseases and invasive operation exposure of the infected patients were high, and the proportion of cardiovascular and cerebrovascular diseases and indwelling catheters were as high as 69.33% and 83.56%, respectively. The differences in the proportions of cardiovascular and cerebrovascular diseases, diabetes mellitus, ≥3 underlying diseases, and surgical and invasive procedures among groups were statistically significant (P<0.05). The distribution of infection specimens in each group showed no statistically significant difference (P>0.05), with sputum, blood, and mid-stream urine specimens being the main detected specimens in all groups. The resistance rates of CRKP to penicillins and cephalosporins were more than 93%, and the resistance rates to aminoglycosides and sulfonamides were relatively low and showed a decline year by year. The resistance rate to ceftazidime/avibactam was only 7.41%, but the resistance rate to tigecycline increased. The difference in resistance rate of CRKP to co-trimoxazole among groups was statistically significant (P<0.05), while the differences in resistance to other antimicrobial agents were not statistically significant (P>0.05). Conclusions The detection rate, clinical characteristics and drug resistance of CRKP infection in different types of departments of medical institutions are different and changing. It is necessary to strengthen the rational use of antibiotics and the prevention and control of nosocomial infection.