Journal Article

Epidemiological Features and Impact of High Glucose Level on Virulence Gene Expression and Serum Resistance of Klebsiella pneumoniae Causing Liver Abscess in Diabetic Patients

Xu, Yuanhong, Li, Tingting, Li, Yajuan, Wang, Hui, Tang, Ling, Cao, Kangli, Huang, Ying

2023

Overview

( ) is a Gram-negative bacterium that is predominantly associated with liver abscesses in global diabetic patients. High levels of glucose in the surrounding of increase its pathogenicity including capsular polysaccharide (CPS) and fimbriae. Other important virulent factors include outer membrane protein A (ompA) and regulator mucoid phenotype A (rmpA). The objective of this investigation was to elucidate the effects of high glucose on and gene expression and serum resistance of causing liver abscess. The clinical history of 57 patients suffering from -caused liver abscesses (KLA) was acquired and their clinical and laboratory manifestations in the presence or absence of diabetes were analyzed. The antimicrobial susceptibility, serotypes, and virulence genes were tested. Clinical isolates of 3 serotype-K1 hypervirulent (hvKP) were used to detect the effect of exogenous high glucose on , and genes expression, and bacterial serum resistance. KLA patients with diabetes showed higher C-reactive protein (CRP) compared to non-diabetic KLA patients. Furthermore, the diabetic group showed increased incidences of sepsis and invasive infections, and their length of hospital stay was also prolonged. Pre-incubation of in high glucose (0.5%) concentration up-regulated , and genes expression. However, cAMP supplementation, which was inhibited by environmental glucose, reversed the increase of and in a cAMP-dependent manner. Moreover, hvKP strains incubated in high glucose also exhibited enhanced protection from serum killing. High glucose levels reflected by poor glycemic control has increased gene expression of and in hvKP by the cAMP signaling pathway and enhanced its resistance to serum killing, thus providing a new and reasonable explanation for the high incidences of sepsis and invasive infections in KLA patients with diabetes.

• Publisher: Dove Medical Press Limited,Taylor & Francis Ltd,Dove,Dove Medical Press
• Subject: Abscesses / Bacteria / Bacterial pneumonia / Biosynthesis / C-reactive protein / Capsular polysaccharides / Clinical isolates / Cyclic adenylic acid / Cyclic AMP / Dextrose / Diabetes / Diabetes mellitus / Diabetics / Disease susceptibility / Drug resistance / Epidemiology / Gene expression / Genes / Genetic research / Glucose / Gram-negative bacteria / Hyperglycemia / Infections / Klebsiella pneumoniae / Laboratories / Liver / liver abscess / Liver diseases / Membrane proteins / ompa / OmpA protein / Original Research / Pathogenicity / Patients / Phenotypes / Pili / Pneumonia / Polyamines / Polysaccharides / Proteins / rmpa / Sepsis / Serotypes / serum resistance / Signal transduction / Statistical analysis / Virulence / Virulence (Microbiology)