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.
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.
ObjectivesTo detect the admission rate and hospital acquired rate of carbapenem-resistant Klebsiella pneumoniae (CRKP) and carbapenem-resistant Acinetobacter baumannii (CRAB) of active surveillance in Emergency Intensive Care Unit patients of West China Hospital of Sichuan University, to examine whether rectal colonization of CRKP and CRAB are associated with nosocomial infection, so as to provide a scientific basis for the prevention and control of CRKP and CRAB.MethodsA nested case-control study was conducted between April and September 2018 in Emergency Intensive Care Unit. Rectal swabs were obtained to screen CRAB and CRKP, and the admission rate of colonization was calculated. According to whether infected with CRKP/CRAB, the patients were divided into case group (infection group) and control group (noninfection group) to determine whether colonization of CRKP/CRAB were independent risk factors for nosocomial infection using logistic regression model.ResultsThe admission rate of CRKP and CRAB patients were 4.08% (18/441) and 8.78% (38/433), and the nosocomial infection rate was 3.63% (16/441) and 18.01% (78/433) separately. Multivariate analysis showed that rectal colonization of CRKP [odds ratio=5.438, 95% confidence interval (1.643, 17.999), P=0.006] was an independent risk factor for nosocomial infection. However, there was no statistical correlation between rectal colonization of CRAB and nosocomial infection [odds ratio=1.449, 95% confidence interval (0.714, 2.942), P=0.305].ConclusionsThe rectal colonization rate of CRAB is higher than that of CRKP, but it does not increase the risk of CRAB infection in patients. Rectal colonization of CRKP is an important factor for infection of patients. Therefore, early detection of CRKP through active surveillance and taking control measures can help reduce the risk of its spread in the hospital.
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.
Liver transplantation is currently the only effective curative treatment for end-stage liver disease. In recent years, with advancements in liver transplantation surgery and anti-rejection drugs, the incidence of surgical complications and organ rejection has gradually decreased. Conversely, transplant-related infections have increasingly become a major factor affecting the prognosis of transplant recipients. Furthermore, due to the progress in critical life support technologies, the time spent in the donor’s intensive care unit (ICU) has been extended, and post-transplant infections originating from the donor, especially donor-derived infection (DDI), have become one of the primary sources of infection for recipients. Studies have shown that infections in liver transplant recipients are often caused by Gram-negative pathogens, particularly carbapenem-resistant Klebsiella pneumoniae (CRKP), which has now become the leading cause of fatal infections in liver transplant recipients. To reduce the risk of donor-derived infections, it is necessary to strengthen donor screening and evaluation, establish standardized testing processes, and adjust the use strategies of post-transplant anti-infective drugs and immunosuppressants. Monitoring the immune status of recipients is also crucial. Multidisciplinary collaboration and the application of new technologies will be key in future infection prevention and control. To promote the prevention and treatment of CRKP-related donor infections, West China Hospital of Sichuan University, in collaboration with international experiences, has organized relevant experts to develop an expert consensus on the prevention and treatment of CRKP-targeted DDI.
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.
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.
ObjectiveTo retrospectively analyze antibiotic resistance and clinical characteristics of Klebsiella pneumoniae strains for guiding the rational use of antibiotics in the area of the Bai nationality.MethodsThe antibiotic resistance and clinical characteristics of Klebsiella pneumoniae strains were retrospective analyzed, which were isolated from specimens of inpatients in First People’s Hospital of Dali between May 2016 and May 2017.ResultsAmong the 1 342 samples of various kinds of samples, 262 strains of Klebsiella pneumoniae were isolated, with the detection rate of 19.52% (262/1342). Clinical isolated strains were mainly from the new pediatric, intensive care unit, respiratory medicine, pediatrics, and mostly from sputum specimens (78.24%, 205/262). By screening of 22 kinds of antimicrobial agents, all strains had ampicillin resistance (100.00%), while none of these strains had ertapenem resistance. Extended-spectrum β-lactamases (ESBLs) positive strains’ resistance rate was higher than ESBLs negative strains (χ2=261.992, P<0.01). There were 76 drug resistant profiles, most of which were multidrug-resistant bacteria except 116 (44.27%) strains were resistant to ampicillin antibiotics only. And the number of strains in other resistant types ranged from 1 to 16. Only one of 262 strains had amikacin resistance, two of them were resistant to imipenem and meroenan.ConclusionsThere are many multidrug-resistant bacteria in Klebsiella pneumoniae in the population of Bai nationality, and there are no extensively drug resistant bacteria and pandrug-resistant bacteria strains. The strains of carbapene-resistant antibiotics should be worthy of clinical attention.
Objective
To investigate the iron regulated locus in Klebsiella pneumoniae isolates from blood culture of liver abscess patients in Sichuan Provincial People’s Hospital.
Methods
From January to December of 2015, a total of 10 isolates of Klebsiella pneumoniae were collected from blood culture of liver abscess patients from Sichuan Provincial People’s Hospital. The genomic DNA was extracted to identify the genes of iroB, iroC, and iroD by PCR, and data was further analyzed by Graphpad Prism 5 software.
Results
Among the 10 Klebsiella pneumoniae clinical strains, 9 strains were iroB positive strains, 9 strains were iroC positive strains, and 10 strains were iroD positive strains, 9 strains were iroB/C/D triple positive.
Conclusion
The current study suggests that the frequency of triple positive of iroB/C/D in Klebsiella pneumoniae is high in isolates from liver abscess patients, the triple positive of iroB/C/D may contribute to liver abscess.
