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 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 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.
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.
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.
ObjectiveTo evaluate the burden of carbapenem-resistant Klebsiella pneumoniae (CRKPN) and carbapenem-resistant Escherichia coli (CRECO), two types of carbapenem-resistant Enterobacteriaceae (CRE), in pediatric patients in Jiangxi Province.MethodsA retrospective investigation was carried out for the distribution of CRKPN/CRECO in pediatric (neonatal group and non-neonatal group) and adult patients in 30 hospitals in Jiangxi Province from January 2016 to December 2018, and the changing trends and detection situations of different patients and types of hospitals were compared and analyzed.ResultsFrom 2016 to 2018, the annual resistance rates of Klebsiella pneumoniae and Escherichia coli to carbapenem in pediatric patients were 5.89%, 4.03%, and 4.24%, respectively, showed a downward trend (χ2trend=5.568, P=0.018). The resistance rate of Klebsiellae pneumoniae and Escherichia coli to carbapenem in neonatal group was higher than that in non-neonatal group (8.44% vs. 3.40%; χ2=63.155, P<0.001) and adult group (8.44% vs. 3.45%; χ2=97.633, P<0.001). In pediatric patients, the 3-year carbapenem resistance rate of Klebsiella pneumoniae was higher than that of Escherichia coli (9.10% vs. 2.48%; χ2=128.177, P<0.001). In non-neonatal pediatric patients, the 3-year resistance rate of Klebsiella pneumoniae and Escherichia coli to carbapenem in maternity and children hospitals was higher than that in general hospitals (4.35% vs. 1.36%; χ2=25.930, P<0.001). CRKPN/CRECO detected in pediatrics were mainly isolated from sputum (31.64%), blood (24.36%), urine (13.82%), and pus (8.36%).ConclusionAlthough the overall resistance rate of Klebsiella pneumoniae and Escherichia coli to carbapenem in pediatric patients showed a downward trend, that in neonatal patients was still high, and the monitoring and prevention and control measures of CRE should be strengthened in neonatal patients.
Compared to classical Klebsiella pneumoniae, hypervirulent Klebsiella pneumoniae (hvKP) exhibits stronger pathogenicity and a greater ability to evade host immune responses. Infections caused by hvKP typically manifest as more severe diseases with higher mortality rates, thereby increasing the complexity and challenges of clinical treatment. The emergence of carbapenem-resistant hvKP (CR-hvKP) exacerbates this predicament. Although there is still confusion regarding the clinical definition and detection standards for hvKP, this article systematically explains the clinical infection characteristics, identification methods, and mechanisms behind the emergence of CR-hvKP. This can enhance clinical staff’s vigilance towards hvKP infections and offer comprehensive and detailed considerations for the diagnosis and treatment of such strains.
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.