Early Diagnosis Of Urinary Tract Infection Research Articles

Evaluation of diagnostic accuracy of urine neutrophil gelatinase-associated lipocalin in patients with symptoms of urinary tract infections: a meta-analysis.

Early and accurate diagnosis of urinary tract infection (UTI) can prevent serious sequelae including chronic kidney disease. Multiple individual studies have identified urine neutrophil gelatinase-associated lipocalin (uNGAL) as a promising biomarker for early diagnosis of UTI. We sought to understand the distribution and diagnostic accuracy of uNGAL values in patients presenting with UTI symptoms. Our systematic literature reviews in PubMed, Embase, and Cochrane Reviews up to March 2024, identified 25 studies reporting mean/median, standard deviation/quartiles, and detection limits of uNGAL in symptomatic patients with and without culture-confirmed UTI. Seventeen studies were in children. Meta-analyses were performed using the quantile estimation (QE) method estimating the distributions of uNGAL, which were then compared between the UTI and non-UTI groups for identifying the best cut-off points maximizing the Youden index. Sensitivity analyses were performed on all 25 studies including adult patients. We found that uNGAL levels were significantly higher in samples with confirmed UTI compared to those without. In pediatric studies, median and 95% confidence interval (CI) of uNGAL values were 22.41 (95% CI of 9.94, 50.54) ng/mL in non-UTI group vs. 118.85 (95% CI of 43.07, 327.97) ng/mL in UTI group. We estimated the cut-off point of 48.43 ng/mL with highest sensitivity (96%) and specificity (97%) in children. Sensitivity analysis including both pediatric and adult studies yielded similar results. The level of uNGAL in symptomatic patients with confirmed UTI is much higher than that reported in patients without UTI. It may be used as a diagnostic tool to identify UTI early among symptomatic patients. The range of uNGAL concentrations and cut-off points reported in subjects with UTI is much lower than that reported in patients with acute intrinsic kidney injury. https://www.crd.york.ac.uk/, PROSPERO (CRD42023370451).

GPs' perspectives on diagnosing childhood urinary tract infections: a qualitative study.

BackgroundDiagnosis and management of childhood urinary tract infection (UTI) is challenging in general practice because of a range of factors.AimTo explore GPs’ perspectives concerning the barriers to and facilitators for diagnosis and management of childhood UTI.Design and settingQualitative study in general practice in Belgium.MethodSemi-structured interviews with 23 GPs from January 2021 to June 2021 were carried out. Interviews were video-recorded and audio-recorded, transcribed verbatim, and analysed using a thematic approach.ResultsThe barriers to early diagnosis of UTI were the assumption of low UTI prevalence and aspecific presentation of UTI in children, difficulties in urine collection, and diagnostic uncertainty. All GPs indicated that they sampled urine in either children with specific UTI features (for example, dysuria, abdominal pain) or unexplained fever. Facilitators for UTI screening were instructional material for parents, skill training for GPs, additional nursing staff, novel non-invasive convenient collection methods, online decision support informing parents when to bring a urine sample to the consultation, and an accurate, easy-to-use point-of-care test for UTI. Empirical antibiotic treatment was initiated based on dipstick test results, clinical features suggestive of UTI, severity of illness, gut feeling, long duration of fever, time of the day, and parents’ ability to judge disease severity.ConclusionThe assumption of a low UTI prevalence, absence of obvious UTI features, and difficult urine sampling might cause childhood UTIs to go undetected in general practice. Diagnostic uncertainty makes appropriate treatment challenging.

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) for the Identification of Bacteria Causing Urinary Tract Infections

Background: Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) technology is a technique which allows microbial identification in clinical microbiology laboratories based on microbial protein profiles. A promising application of the MALDI-TOF technique comprises carrying out identification from direct urine samples. Objectives: The aim of this study is to evaluate the performance of MALDI-TOF MS system for the rapid identification of clinically relevant urinary tract pathogens in urine samples to the species level. Methodology: two hundred (200) urine samples with findings suggestive of urinary tract infections (UTI) were identified directly by MALDI-TOF MS, and same samples were identified from culture on MALDI-TOF MS. 73 colonies from 73 samples were further identified by Bd Phoneix and PCR. Results: MALDI-TOF MS directly from samples identified 174 samples (91 to the species level 83 to genus level), while MALDI-TOF MS after culture identified 191 samples (187 to the level of species, and 4 to genus level). In addition, 9 samples gave no results from the direct method and no growth in culture. The sensitivity and specificity of direct method compared to after culture method was 91.1% and 100%, respectively. Colonies of 73 samples were detected by the BD Phoneix automated identification system and by PCR. The results were identical among the three systems. Conclusion: The ability of MALDI-TOF MS’s to detect microorganisms from urine samples directly can provide early diagnosis of UTIs and avoid the inadequate or unnecessary empirical antimicrobial treatment.

Incidence And Characteristics Of Urinary Tract Infections Among Febrile Children In Early Childhood

Introduction: Fever is the most common cause for concern for parents and a reason to seek help from a GP or emergency centers. The high temperature in children in most cases is short-lived and is a protective reaction that stops or slows down the development of many microorganisms, stimulates the immune response, and provides rest to the sick child. Negative effects are dehydration, hypovolemia, hyperthermic seizures in childhood, hypotension to collapse. Urinary tract infections (UTIs) can occur only with fever or with fever and non-specific symptoms such as malaise, vomiting, abdominal pain, and jaundice. Antibiotic treatment for fever without a proven cause may mask an existing urinary tract infection. Aim : The aim of this article is to review the scientific literature for a period of 40 years on the incidence of UTIs in infancy and early childhood in children with fever. Methods: Analysis of Bulgarian and foreign literature sources according to the PubMed and Google Scholar databases for a period of 40 years has been conducted. Results: The analysis of the data from the scientific literature showed that the frequency of UTI varies depending on gender and age. In most studies, the incidence of UTI in febrile children under 24 months of age, both sexes, with or without additional symptoms of UTI, was between 5% and 15%. In boys, the prevalence is highest in the first 3 months of life and then shows a declining trend, while in girls the prevalence is highest in the first 12 months of life. There is evidence in the literature that fever (rectal temperature ≥ 39°C) and uncircumcised status are more likely to be linked to UTI in boys. E. coli is the most common bacterial infection in early childhood and is the leading cause of UTI in this age group. Conclusion : The GP needs to make efforts to educate parents on the diagnosis, consequences and appropriate treatment of obscure febrile conditions, and UTI should be excluded. It is necessary to pay attention to the method of measuring the temperature, the differences in the values in the different measuring points. In this aspect, the GP should perform an in-depth analysis for early diagnosis of UTI in all boys under 12 months of age and girls under 24 months of age with unexplained fever, temperature above ≥ 38°C measured rectally for 3 minutes.

Biomarkers for febrile urinary tract infection in children.

The sensitivity and specificity of the leukocyte esterase test for the diagnosis of urinary tract infection (UTI) are suboptimal. Recent studies have identified markers that appear to more accurately differentiate children with and without UTI. The objective of this study was to determine the accuracy of these markers, which included CCL3, IL-8, CXCL1, TNF-alpha, IL-6, IFN-gamma, IL-17, IL-9, IL-2, and NGAL, in the diagnosis of UTI. This was a prospective cross-sectional study to compare inflammatory proteins between urine samples from febrile children with a UTI, matched febrile controls without a UTI, and asymptomatic healthy controls. We included 192 children (75 with febrile UTI, 69 febrile controls, and 48 asymptomatic healthy controls). Urinary proteins that best discriminated between febrile children with and without UTI were NGAL, a protein that exerts a local bacteriostatic role in the urinary tract through iron chelation; CCL3, a chemokine involved in leukocyte recruitment; and IL-8, a cytokine involved in neutrophil recruitment. Levels of these proteins were generally undetectable in asymptomatic healthy children. NGAL, CCL3, and IL-8 may be useful in the early diagnosis of UTI. ClinicalTrials.gov (NCT01391793) A higher resolution version of the Graphical abstract is available as Supplementary information.

A multivalent aptamer-based electrochemical biosensor for biomarker detection in urinary tract infection

Lactoferrin is a multifunctional protein of the transferrin family and is known as a biomarker for various clinical diseases including urinary tract infection (UTI). However, wide concentration range of lactoferrin in urine samples due to the high interpatient variations, requires a more practical biosensor. In this article, we used a novel multivalent aptamer immobilized on the surface of screen-printed gold electrode (aptamer/SPGE) to develop the first electrochemical aptasensor for label-free detection of lactoferrin with wide dynamic detection range and high sensitivity. The performance of the fabricated biosensor was tested using electrochemical impedance spectroscopy and differential pulse voltammetry. The multivalent aptamer as the bioreceptor with high affinity and good specificity against human lactoferrin, acts to enhance the electrochemical signals and widen the working window. The aptamer/SPGE demonstrates superior sensing performances for lactoferrin in buffer solution, with a wide linear range of 10 to 1300 ng/mL with LOD of 0.9 ng/mL, as well as high selectivity, and excellent reproducibility. Besides, the constructed aptasensor was successfully applied to quantify lactoferrin concentrations in spiked urine solutions. Owing to excellent sensitivity, ease of miniaturization, simple sensing procedure, low-cost, and fast response, the proposed electrochemical aptasensor indicates a great potential towards the development of lactoferrin analysis systems, which would be helpful in the early diagnosis of UTI.

Performance Evaluation of Four Commercial Point-of-Care Testing Urine Analyzers for Diagnosing Urinary Tract Infection.

Urinalysis is used as a screening tool in case of a clinical suspicion of urinary tract infection (UTI). The purpose of this study is to evaluate the analytical performance, agreement, and screening value of four commercial point-of-care testing (POCT) urine analyzers for UTI. The following four POCT analyzers were evaluated: Clinitek Status+, BW-200, Hipee S2, and URS-14K. The agreement of the four analyzers with the laboratory standard was assessed. The diagnostic indicators of the screening tests performed using POCT analyzers for UTI were calculated against the bacterial culture as the gold standard. Overall agreement of the four analyzers was good. For nitrite and leukocytes, all the analyzers showed substantial or excellent agreement with the laboratory reference standard, whereas agreement for erythrocytes varied from moderate to excellent. With each POCT analyzer, combined detection of nitrite, leukocytes, and erythrocytes provided better diagnostic performance than individual detection. Combined detection had higher sensitivity and negative predictive value, while the specificity and positive predictive value were higher for single detection of nitrite. Present findings demonstrate that the overall performance of the four POCT urine analyzers was sufficient for routine use for screening UTI. A result positive for nitrite is helpful for early diagnosis of UTI, and a result negative for the combination of nitrite, leukocytes, and erythrocytes is helpful for early elimination of UTI.

Urine YKL-40 versus Urine NGAL as Potential Markers for Diagnosis of Urinary Tract Infection in Febrile Pediatric Patients

Early diagnosis of urinary tract infection (UTI) in pediatric patients is a prob-lem due to the absence of specific symptoms and difficulty in obtaining the proper urine sample. These difficulties increase the need for effective biomarker for UTI diagnosis in young patients. Neutrophil gelatinase-associated lipocalin (NGAL) is proved to be a marker for UTI diagnosis. YKL-40 is a glycosyl hydrolase which is produced locally at the sites of inflammation. The objective of our study is to assess the value of YKL-40 as a possible marker for UTI diagnosis in febrile children and to compare its value versus NGAL. Urine culture was used as a gold standard for UTI diagnosis. The study enrolled three groups; febrile children with positive urine culture, febrile children with negative urine culture, and controls without fever and with negative urine culture. Each group included 50 children from patients attended outpatients clinics department of Mansoura University Children Hospital. For each patient enrolled in the study, complete blood count, C-reactive protein, serum creatinine, urine creatinine, routine urine analysis and urine culture were assessed. Using ELISA test, urine values of NGAL (uNGAL) and YKL-40 (uYKL-40) were measured and normalized to urine creatinine (uNGAL/uCr) and (uYKL40/uCr) respectively. The values of uNGAL, uYKL-40, uNGAL/Cr and uYKL-40/Cr were significantly higher in febrile UTI group. The receiver operating curve (ROC) show the optimum cut off value for urine YKL-40 (171.5 pg) with 84% senstivity, 82% specificity and the area under the ROC curve (AUC) 0.95. The optimum cutoff value of uYKL-40/Cr was (159.2 pg/mg) with 72% sensitivity, 71% specificity and 0.81 AUC. Higher sensitivity and specificity of uYKL-40 and uYKL40/Cr compared to uNGAL and uNGAL/Cr respectively were observed. In conclusion, the diagnostic value of uYKL-40 is superior to that of uNGAL. Urine YKL-40 could be a good marker for diagnosis of UTI in febrile pediatric patients.

The struggle to diagnose UTI in children under two in primary care.

The incidence of urinary tract infection (UTI) in childhood is highest in infancy and accounts for 5% of febrile infants. Reflux nephropathy following UTI in early childhood is the commonest preventable cause of chronic renal failure. Recent guidelines aim to improve the diagnosis and management of UTI in small children. To assess management of febrile children and UTI in children under 2 years amongst GPs, and to identify some reasons for the difficulties in diagnosing UTI. Questionnaire distributed by periodical journal. Eighty-two GPs responded, of whom 61 (74%) were unaware of the recent Royal College of Physicians guidelines on childhood UTI. Seventy-seven GPs (94%) would find guidelines helpful on when to send a urine sample for culture from a child under 2 years. Only 11 GPs (14%) regularly sent urine from febrile infants and toddlers; 48 GPs (63%) sent urine from only 0-10% of patients; 21 (26%) were unable to collect urine at all from these children. Several difficulties were identified by GPs regarding investigation for UTI in children. These related to practical difficulties in urine collection and culturing, lack of professional awareness of the importance of UTI and concerns about the costs of investigation. GPs frequently do not investigate for UTI in febrile children due to practical difficulties, lack of awareness and financial costs. National guidelines need to be disseminated and implemented effectively to reach target groups. Further scope for research into a simple, cheap method to collect and test urine has been highlighted as a priority to improve early diagnosis of UTI. Management of UTI in primary care can be improved with carefully evaluated strategies and this could lead to a reduction in the prevalence of renal scarring.