Role of Self-Sampling for Cervical Cancer Screening: Diagnostic Test Properties of Three Tests for the Diagnosis of HPV in Rural Communities of Cuenca, Ecuador

Background: HPV primary screening has shown effectiveness for cancer prevention; however, gynaecological examination is considered uncomfortable. Self-sampling methods increase the acceptance of screening. The aim of this study is to compare the sensitivity and specificity of clinician sampling versus vaginal and urine self-sampling for HPV diagnosis. Methods: A diagnostic test study was conducted in a rural parish of Cuenca, Ecuador. A total of 120 women participated. Each participant self-collected urine and vaginal samples and underwent clinician sampling for HPV testing. The latter was considered as the golden standard. All three samples were processed with the same amplification and hybridization protocol for HPV detection (Hybribio) following the manufacturer’s instructions. Results: Characteristics of the participants were: median age 35 years; 40.8% married; 46.7% had a primary level of education; and median age of sexual onset, 17.6 years. The prevalence of any type of HPV with clinician sampling was 15.0%, 17.5% with urine sampling and 18.3% with vaginal self-sampling. Self-sampling sensitivity reached 94.4% (IC 74.2–99.9), and specificity 92.1% (IC 85.2–95.9). Urine sampling had a sensitivity of 88.8% (IC 67.2, 96.9), and specificity 94.1% (IC 67.2–96.9). The negative predictive value was 98.9% (IC 94.2–99.8) for vaginal self-sampling and 97.6% (IC 92.6–99.4) for urine sampling. Conclusions: This study shows that vaginal and urine self-sampling methods have similar sensitivity and specificity compared with clinician sampling for the diagnosis of HPV. The correlation between HPV genotypes among the three tests is satisfactory.

How Many Urine Samples Are Needed to Accurately Assess Exposure to Non-Persistent Chemicals? The Biomarker Reliability Assessment Tool (BRAT) for Scientists, Research Sponsors, and Risk Managers

In epidemiologic and exposure research, biomonitoring is often used as the basis for assessing human exposure to environmental chemicals. Studies frequently rely on a single urinary measurement per participant to assess exposure to non-persistent chemicals. However, there is a growing consensus that single urine samples may be insufficient for adequately estimating exposure. The question then arises: how many samples would be needed for optimal characterization of exposure? To help researchers answer this question, we developed a tool called the Biomarker Reliability Assessment Tool (BRAT). The BRAT is based on pharmacokinetic modeling simulations, is freely available, and is designed to help researchers determine the approximate number of urine samples needed to optimize exposure assessment. The BRAT performs Monte Carlo simulations of exposure to estimate internal levels and resulting urinary concentrations in individuals from a population based on user-specified inputs (e.g., biological half-life, within- and between-person variability in exposure). The BRAT evaluates—through linear regression and quantile classification—the precision/accuracy of the estimation of internal levels depending on the number of urine samples. This tool should guide researchers towards more robust biomonitoring and improved exposure classification in epidemiologic and exposure research, which should in turn improve the translation of that research into decision-making.

Developing a Food Exposure and Urine Sampling Strategy for Dietary Exposure Biomarker Validation in Free-Living Individuals

SCOPE

Dietary choices modulate the risk of chronic diseases and improving diet is a central component of public health strategies. Food-derived metabolites present in urine could provide objective biomarkers of dietary exposure. To assist biomarker validation, this work aims to develop a food intervention strategy mimicking a typical annual diet over a short period of time and assesses urine sampling protocols potentially suitable for future deployment of biomarker technology in free-living populations.

METHODS AND RESULTS

Six different menu plans comprehensively represent a typical UK annual diet that is split into two dietary experimental periods. Free-living adult participants (n = 15 and n = 36, respectively) are provided with all their food, as a series of menu plans, over a period of three consecutive days. Multiple spot urine samples are collected and stored at home.

CONCLUSION

A successful food exposure strategy is established following a conventional UK eating pattern, which is suitable for biomarker validation in free-living individuals. The urine sampling procedure is acceptable for volunteers and delivered samples suitable for biomarker quantification. The study design provides scope for validation of existing biomarker candidates and potentially for discovery of new biomarker leads, and should help inform the future deployment of biomarker technology for habitual dietary exposure measurement.

Long-term outcomes of urinary tract infection (UTI) in Childhood (LUCI): protocol for an electronic record-linked cohort study

INTRODUCTION

Current guidelines advise the prompt diagnosis and treatment of urinary tract infection (UTI) in children to improve both short and longer term outcomes. However, the risk of long-term complications following childhood UTI is unclear.UTI is relatively common but difficult to diagnose in children as symptoms are non-specific. Diagnosis requires a urine sample, but sampling is difficult and infrequent, and it is not clear if sampling should be given greater priority in primary care. The LUCI study will assess the short, medium and longer term outcomes of childhood UTI associated with routine and systematic sampling practices.

METHODS AND ANALYSIS

Two data sets will be established. The first will consist of routinely collected data (hospital, general practice (GP), microbiology) from children born and resident in Wales, linked via the Secure Anonymised Information Linkage (SAIL) Databank (an 'e-cohort'). Urine sampling in this data set reflects normal practice 'routine sampling'. Outcomes (including renal scarring, hypertension, end-stage renal failure, hospital admissions, GP consultations, antibiotic prescriptions) for children with at least one UTI confirmed with microbiological culture (mcUTI) or no mcUTI before the age of 5 will be compared.The second will combine data from two prospective observational studies ('DUTY' and 'EURICA') employing systematic urine sampling for children presenting to primary care with acute, undifferentiated illness, linked to routine data via SAIL (Wales) and NHS Digital (England). Outcomes (as above, plus features of mcUTI) for children with an mcUTI in this data set, identified through systematic urine sampling, will be compared with those with an mcUTI identified through routine urine sampling (data set 1).

ETHICS AND DISSEMINATION

The study protocol has been approved by NHS Wales Research Ethics Committee and the Health Research Authority's Confidentiality Advisory Group. Methods of innovative study design and findings will be disseminated through peer-review journals and conferences. Results will be of interest to clinical and policy stakeholders in the UK.

Pediatrician noncompliance with the American Academy of Pediatrics guidelines for the workup of UTI in infants

BACKGROUND

The American Academy of Pediatrics (AAP) guidelines on the workup for urinary tract infections (UTIs) in infants discourages the use of bagged urine specimens for urine culture. We report the results of a survey to assess urine collection preferences and adherence to AAP guidelines in clinical practice.

METHODS

A 29-question survey was e-mailed to pediatrician AAP members to determine their preferred method of urine collection in hypothetical infant patients.

RESULTS

Data from 155 respondents were analyzed. In febrile, circumcised boys, up to 18% preferred bagged specimens for urine culture, against AAP recommendations. In febrile girls, 13% of respondents preferred bagged specimens. There was no significant relationship between adherence to AAP guidelines and respondent's age, gender, years in practice, fellowship training, academic affiliation, or other demographic factors.

CONCLUSIONS

Up to 18% of practitioners prefer bagged specimens over more sterile ones in the workup of febrile UTIs in infants, against AAP guidelines.

Suprapubic Bladder Aspiration or Urethral Catheterization: Which is More Painful in Uncircumcised Male Newborns?

BACKGROUND

The aim was to compare the intensity of pain caused by suprapubic aspiration (SPA) and urethral catheterization for urine sampling in premature infants.

METHODS

A prospective randomized controlled design with 80 premature infants in Alzahra University Hospital, Isfahan, Iran was conducted. Premature newborns who needed urine samples for microbiologic analysis were randomly assigned into two groups: SPA group and urethral catheterization group. Newborn faces and upper parts of the body were videotaped during the study and the pain was assessed during urine collection using Premature Infant Pain Profile (PIPP) score. Furthermore, crying time compared between groups.

RESULTS

The mean crying time was significantly higher in SPA than urethral catheterization group (77 vs. 34.4 s) (P < 0.001). The PIPP score was significantly lower in urethral catheterization group (13.4) than SPA group (11.5) P < 0.001. The success rate of SPA was 53% compared with 71% success rate of urethral catheterization.

CONCLUSIONS

SPA is more painful than urethral catheterization in premature male infants as assessed by PIPP score and is more likely leads to procedure failure.