[Microbiological diagnosis of urinary tract infections]

[Effects of D-tagatose, Stevia and Sucrose on pH and oral bacterial activity in dentistry students. A randomized controlled trial]

BACKGROUND

stevia and D-tagatose have shown a reduction in total calorie and carbohydrate intake as a substitute for sucrose, demonstrating a stabilizing effect on pH and bacterial proliferation.

OBJECTIVE

to evaluate the effect of D-tagatose, stevia and sucrose on salivary pH and bacterial activity in odontology students.

METHODOLOGY

a controlled study of parallel and randomized groups with a single blind, whose sample considered three groups subjected to a mouthwash of D-tagatose (n = 10), stevia (n = 10) and sucrose (n = 10). These solutions were administered over 1 minute in a single 6.4 % concentrated dose. Data collection and analysis considered the recording of salivary pH 5 min before exposure to the sweetener, immediately after expulsion of the mouthwash and 15 min later, 30 min, 45 min and 48 hours. The counting of the final number of colony-forming units per mL (CFU/mL) was counted using the salivary samples obtained immediately after exposure of the sweetener together with the sample obtained 30 minutes later, with the cultures performed on agar plates.

RESULTS

D-tagatose, stevia and sucrose presented significant differences in total CFU/mL at 30 minutes (p < 0.001), while salivary pH showed significant differences at 48 hours after administration (p < 0.001).

CONCLUSION

D-tagatose, stevia and sucrose present significant differences in total CFU/mL and salivary pH, these findings being a possible indication of a partial inhibitory effect on bacterial metabolism.

Identification and antibiogram of Enterobacterales from direct urine samples using matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) technology and disk-plate diffusion technique

Identification and antibiogram of uropathogenic microorganisms from direct urine samples present a great clinical impact. Here, we present a combined procedure to determine identification (IDd) of bacteria through MALDI-TOF-MS technology and antibiogram (ATBd) using disk-plate diffusion technique, of UTI-producing Enterobacterales against the most used antibiotics. Ninety-four urine samples with presence of pyuria and Gram-negative bacilli were selected. The IDd showed a high success rate (90%). ATBd procedure showed a high correlation for tested antibiotics. This simplified, low cost and reduced work time two-step procedure significantly reduces results turnaround time and benefit the clinical management of patients with UTI.

Factores asociados a infección de vías urinarias luego de una prostatectomía

Introducción y Objetivo La cirugía de próstata es un procedimiento frecuente en varones mayores. Existen diferentes técnicas, cuya elección depende de la patología a tratar, de la experiencia del especialista, y de la disponibilidad técnica. Entre sus complicaciones se encuentra la infección del tracto urinario, que ocasiona incremento en morbimortalidad y costos para el sistema de salud. El objetivo principal de este estudio fue evaluar los factores relacionados con la aparición de infección urinaria luego de este tipo de cirugía.

Materiales y Métodos Se realizó un estudio de casos y controles en una población de pacientes sometidos a prostatectomía del 2018 hasta principios del 2020 en Medellín, Colombia. Los casos correspondieron a los pacientes que presentaron infección de vías urinarias hasta 30 días tras la prostatectomía. Se estimó la asociación entre casos y controles por medio del cálculo de la razón de disparidad (RD), la cual se ajustó con una regresión logística y con un modelo aditivo generalizado multivariado.

Resultados Se identificaron 96 casos incidentes de infección del trato urinario luego de la prostatectomía, con una prevalencia de 8.99%. La frecuencia de solicitud de urocultivo preoperatorio fue de 52,92% (intervalo de confianza del 95% [IC95%]: 48,34–57,44%). Las variables independientemente asociadas con la aparición de infección urinaria fueron: solicitud de urocultivo prequirúrgico, número de dosis, y tipo de antibiótico usado para la profilaxis. Particularmente, se encontró como factor protector el uso de aminoglucósidos. En los pacientes con infección urinaria, los principales gérmenes aislados fueron: Eschirichia coli, Pseudomonas aeruginosa, Klepsiella pneumoniae, Enterococos faecalis y Serratia marcescens.

Conclusión Este estudio demuestra que factores como la solicitud preoperatoria de urocultivo y el uso de aminoglucósidos en los esquemas de profilaxis quirúrgica reducen la probabilidad de desarrollar una infección urinaria luego de una prostatectomía.

Association between TLR4 polymorphisms (896 A>G, 1196 C>T, - 2570 A>G, - 2081 G>A) and virulence factors in uropathogenic Escherichia coli

Escherichia coli is the main etiological agent of urinary tract infections. Its virulence factors are important during the initial interaction stage with the host as they enable colonization of urinary tract tissues. The genetic markers evidencing susceptibility to develop recurrent infections have been previously described. Toll-like receptors are critical sensors of microbial attacks, and they are also effectors of the individual's innate defense for elimination of pathogens. The aim of this study was to evaluate the association between functional polymorphisms (896 A>G, 1196 C>T, - 2570 A>G, - 2081 G>A) and susceptibility to develop urinary tract infections as well as E. coli virulence factors. This study includes 100 samples from patients diagnosed with UTI and 100 samples from uninfected subjects. A conventional urine culture was performed and the isolates were identified by using the Vitek automated system. TLR4 gene polymorphisms were identified by the PCR-RFLP technique. The hlyA, fimH, papC, iutA and cnf1 virulence factors as well as the E. coli phylogenetic group were assessed by PCR. In this study, it was observed that the presence of the - 2570 polymorphism represents a risk of UTI (p < 0.01), whereas - 2081 confers protection (p < 0.01). The 896A>G and 1196C>T polymorphisms were associated with the E. coli virulence factors fimH and hlyA, respectively (p < 0.05). The B2 group was the most frequent in clinical isolates (51%), and it displayed more virulence factors regarding other phylogenetic groups (p ≤ 0.05). An interesting finding was that strains considered as commensals, belonging to groups A and B1, can cause UTI and present virulence factors. Polymorphisms occurring in the TLR4 promoter region are correlated with susceptibility or risk of UTI, whereas structural polymorphisms are associated with the recognition of virulence factors displayed by E. coli.

Clinical and laboratory characteristics of acute community-acquired urinary tract infections in adult hospitalised patients

Urinary tract infections (UTI) cause a great number of morbidity and mortality. These infections are serious complications in pregnancy, patients with diabetes, polycystic kidneys disease, sickle cell anaemia, kidney transplant and in patients with functional or structural anomalies of the urinary tract. The aim of this investigation was to determine a dominant causative agents of UTI and some of the clinical and laboratory characteristics of acute community-acquired UTI in adult hospitalised patients. We studied 200 adult patients with acute community-acquired UTI hospitalised in the Clinic for Infectious Diseases Tuzla from January 2006 to December 2007. The patients were divided into two groups: a group of patients with E. coli UTI (147) and a group of patients with non-E. coli UTI (53). In these two groups, the symptoms and signs of illness, blood test and urine analysis results were analysed. Our results have shown that the patients with E. coli UTI frequently had fever higher than 38,5 degrees C (p<0,0001), chills (p=0,0349), headache (p=0,0499), cloudy urine (p<0,0001), proteinuria (p=0,0011) and positive nitrite-test (p=0,0002). The patients with non-E. coli UTI frequently had fever lower than 38,5 degrees C (p<0,0001) and urine specific gravity <1015 (p=0,0012). There was no significant difference in blood test results between patients with E. coli and non-E. coli UTI. These clinical and laboratory findings can lead us to early etiological diagnosis of these UTI before urine culture detection of causative agents, which takes several days. Early etiological diagnosis of the E. coli and non-E. coli UTI is necessary for an urgent administration of appropriate empirical antibiotic treatment. This is very important in prevention of irreversible kidney damage, prolonged treatment, complications, as well as recidives and chronicity of the illness.