Differential interleukin-1β induction by uropathogenic Escherichia coli correlates with its phylotype and serum C-reactive protein levels in Korean infants

Abstract

Urinary tract infection (UTI) is one of the most common bacterial infections in infants less than age 1 year. UTIs frequently recur and result in long-term effects include sepsis and renal scarring. Uropathogenic Escherichia coli (UPEC), the most prevalent organism found in UTIs, can cause host inflammation via various virulence factors including hemolysin and cytotoxic necrotizing factors by inducing inflammatory cytokines such as interleukin (IL)-1β. However, the ability of each UPEC organism to induce IL-1β production may differ by strain. Furthermore, the correlation between differential IL-1β induction and its relevance in pathology has not been well studied. In this study, we isolated UPEC from children under age 24 months and infected bone-marrow derived macrophages with the isolates to investigate secretion of IL-1β. We found that children with higher concentrations of C-reactive protein (CRP) were more likely to harbor phylotype B2 UPEC strains that induced more IL-1β production than phylotype D. We also observed a significant correlation between serum CRP level and in vitro IL-1β induction by phylotype B2 UPEC bacteria. Our results highlight the diversity of UPEC in terms of IL-1β induction capacity in macrophages and suggest a potential pathogenic role in UTIs by inducing inflammation in infants.

Biomarkers for febrile urinary tract infection in children

“…IL-1β is a pro-inflammatory biomarker that is secreted by macrophages in response to infection and serves to recruit neutrophils and other leukocytes. IL-1β is released very early in response to infection ( 26 , 27 ). IL-1β has been shown to be elevated in children with cystitis ( 28 ) and acute pyelonephritis ( 27 , 29 ).…”

Establishment of a prediction model for histological chorioamnionitis and its association with outcomes of premature infants

“…This was allied with the results of our study. This may be because cytokines including interleukin 1, interleukin 6, and tumor necrosis factor alpha can induce acute-phase proteins in the liver such as CRP in infections and other inflammatory states ( 22 ). WBC was higher in pregnant women with HCA ( 23 ), and we also identified that WBC might be a reliable predictor for HCA.…”