RESUMO
Urinary interleukin-6 (UIL-6) and urinary interleukin-8 (UIL-8) concentrations were measured by immunoassay in 39 and 34 patients respectively, hospitalized with febrile urinary tract infection (UTI), and in 37 and 32 age-, race- and sex-matched febrile control children respectively, with negative urine cultures. UIL-6 and UIL-8 concentrations, measured in picograms per milliliter and corrected for creatinine, were compared with clinical and laboratory indicators of inflammation and bacterial virulence factors of Escherichia coli. Median UIL-6 concentrations at the time of admission were 397 pg/ml (range 0-65,789 pg/ml) in the 37 patients compared to 0 pg/ml (range 0-473.8 pg/ml) in the 37 controls (P < 0.0001). Median UIL-8 concentrations at the time of admission were 5809 pg/ml (range 0-347,368 pg/ml) in the 32 patients compared to 0 pg/ml (range 0-2231 pg/ml) in the 32 controls (P < 0.0001). UIL-6 and UIL-8 concentrations were lower (P < 0.0001 for UIL-6 and P = 0.0005 for UIL-8) in follow-up urine samples from UTI patients, obtained 48 h after the initiation of antibiotic therapy. UIL-6 and UIL-8 concentrations were statistically significantly correlated with urine white blood cells (WBC). UIL-8 concentrations were elevated in patients with E. coli organisms producing hemolysin. UIL-6 and UIL-8 are elevated in children with febrile UTI and decrease in response to antibiotic therapy. Magnitude of UIL-8 response is associated with hemolysin production, a bacterial virulence factor of E. coli. UIL-6 and UIL-8 concentrations are statistically correlated with urine WBC. UIL-6 and UIL-8 may be mediators of inflammation in children with febrile UTI.
Assuntos
Interleucina-6/urina , Interleucina-8/urina , Infecções Urinárias/urina , Criança , Pré-Escolar , Creatinina/urina , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/urina , Feminino , Febre/urina , Humanos , Imunoensaio , Lactente , Recém-Nascido , Masculino , Valores de Referência , Estudos Retrospectivos , Infecções Urinárias/microbiologiaRESUMO
Using whole bacteria, rather than extracted, purified DNA samples, we amplified the papE gene sequences from 63 Escherichia coli isolates belonging to O serogroups O1, O2 and O6. These isolates were from collections separated temporally as well as geographically: from four cities in the US and one in Sweden. PCR amplified papE products were digested with restriction endonucleases and the relative sizes of the fragments compared for each strain. For 41 of the strains, we found a correlation between the papE restriction fragment length polymorphism (RFLP) and the complete serotype. Furthermore, we were able to detect the presence of duplicate copies of the gene in 14 of the isolates; these 14 isolates were among the 22 that did not exhibit a correlation between the RFLP of their amplified papE sequences and their complete serotype. We conclude that RFLP analysis of PCR products is a rapid and relatively simple method for examining the DNA of E. coli containing the pap gene sequence.
Assuntos
DNA Bacteriano/análise , Proteínas de Escherichia coli , Escherichia coli/genética , Fímbrias Bacterianas/genética , Proteínas de Membrana , Polimorfismo de Fragmento de Restrição , ATPases Translocadoras de Prótons , Animais , Proteínas de Bactérias/genética , Criança , Primers do DNA/química , Sondas de DNA/química , DNA Bacteriano/genética , Eletroforese em Gel de Ágar , Escherichia coli/química , Escherichia coli/classificação , Infecções por Escherichia coli/microbiologia , Feminino , Fímbrias Bacterianas/química , Genes Bacterianos/genética , Humanos , Lactente , Família Multigênica/genética , Hibridização de Ácido Nucleico , Antígenos O/imunologia , Reação em Cadeia da Polimerase , Ovinos , Suécia , Estados Unidos , Infecções Urinárias/microbiologiaRESUMO
Many blood group antigens, genetically controlled carbohydrate molecules, are found on the surface of uroepithelial cells and may affect bacterial adherence and increase the frequency of urinary tract infection (UTI) in adults. Sixty-two children aged 2 weeks to 17 years (mean, 2.3 years) who were hospitalized with fever in association with UTIs caused by Escherichia coli had complete (n = 50) or partial (n = 12) erythrocyte antigen typing to determine the role of erythrocyte antigens and phenotypes in UTI in children; 62 healthy children undergoing nonurologic elective surgery, matched 1 to 1 for age, sex, and race to the patient group, formed the control group. In univariate tests, patients and control subjects did not differ in ABO, Rh, P, Kell, Duffy, MNSs, and Kidd systems by the McNemar test of symmetry (p > 0.05). The frequency of the Lewis (Le) (a-b-) phenotype was higher (16/50 vs 5/50; p = 0.0076) and the frequency of the Le(a + b +) phenotype was lower (8/50 vs 16/50; p = 0.0455) in the patient population than in the control subjects. A stepwise logistic regression model to predict UTI with the explanatory variables A, B, O, M, N, S, s, Pl, Lea, and Leb showed that only the Lea and Leb antigens entered the model with p < 0.1. The Le(a-b-) phenotype was associated with UTI in this pediatric population. The relative risk of UTI in children with the Le(a-b-) phenotype was 3.2 (95% confidence interval, 1.3 to 7.9). Specific blood group phenotypes in pediatric populations may provide a means to identify children at risk of having UTI.