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Concept: Urinalysis


Objective To determine if a simple stimulation method increases the rate of infant voiding for clean catch urine within five minutes.Design Randomised controlled trial.Setting Emergency department of a tertiary paediatric hospital, Australia.Participants 354 infants (aged 1-12 months) requiring urine sample collection as determined by the treating clinician. 10 infants were subsequently excluded.Interventions Infants were randomised to either gentle suprapubic cutaneous stimulation (n=174) using gauze soaked in cold fluid (the Quick-Wee method) or standard clean catch urine with no additional stimulation (n=170), for five minutes.Main outcome measures The primary outcome was voiding of urine within five minutes. Secondary outcomes were successful collection of a urine sample, contamination rate, and parental and clinician satisfaction with the method.Results The Quick-Wee method resulted in a significantly higher rate of voiding within five minutes compared with standard clean catch urine (31% v 12%, P<0.001), difference in proportions 19% favouring Quick-Wee (95% confidence interval for difference 11% to 28%). Quick-Wee had a higher rate of successful urine sample collection (30% v 9%, P<0.001) and greater parental and clinician satisfaction (median 2 v 3 on a 5 point Likert scale, P<0.001). The difference in contamination between Quick-Wee and standard clean catch urine was not significant (27% v 45%, P=0.29). The number needed to treat was 4.7 (95% confidence interval 3.4 to 7.7) to successfully collect one additional urine sample within five minutes using Quick-Wee compared with standard clean catch urine.Conclusions Quick-Wee is a simple cutaneous stimulation method that significantly increases the five minute voiding and success rate of clean catch urine collection.Trial registration Australian New Zealand Clinical Trials Registry ACTRN12615000754549.

Concepts: Infant, Clinical trial, Urinalysis, Sample size, Likert scale, Randomized controlled trial, Pediatrics, Normal distribution


Kawasaki disease (KD) is a systemic vasculitis and affects many organ systems. It often presents sterile pyuria, microscopic hematuria, and proteinuria due to renal involvement. The aims of this study were to define clinical characteristics of acute KD patients with pyuria and to analyze meaning of pyuria in KD.

Concepts: Arthralgia, Nephrotic syndrome, Urinalysis, Kawasaki disease, IgA nephropathy, Glomerulonephritis, Nephrology, Vasculitis


Up to 50% of urinary tract infections (UTIs) in young children are missed in primary care. Urine culture is essential for diagnosis, but urine collection is often difficult. Our aim was to derive and internally validate a 2-step clinical rule using (1) symptoms and signs to select children for urine collection; and (2) symptoms, signs, and dipstick testing to guide antibiotic treatment.

Concepts: Fever, Greek loanwords, Fatigue, Urinalysis, Disease, Urine, Kidney, Urinary tract infection


AIM: To describe and test a new technique to obtain midstream urine samples in newborns. DESIGN AND METHODS: This was a prospective feasibility and safety study conducted in the neonatal unit of University Infanta Sofía Hospital, Madrid. A new technique based on bladder and lumbar stimulation manoeuvres was tested over a period of 4 months in 80 admitted patients aged less than 30 days. The main variable was the success rate in obtaining a midstream urine sample within 5 min. Secondary variables were time to obtain the sample and complications. RESULTS: This technique was successful in 86.3% of infants. Median time to sample collection was 45 s (IQR 30). No complications other than controlled crying were observed. CONCLUSIONS: A new, quick and safe technique with a high success rate is described, whereby the discomfort and waste of time usually associated with bag collection methods can be avoided.

Concepts: Hematuria, Infant mortality, Median, Urine, Urinalysis, Time, Pediatrics, Infant


OBJECTIVES:Mesalamine non-adherence is common among patients with ulcerative colitis (UC), and can be difficult to identify in practice. We sought to determine whether a random urine test for salicylates could be used as a marker of 5-aminosalicylic acid (5-ASA) ingestion and identify patients at risk of non-adherence. Our aim is to determine whether measurement of salicylates in a random urine sample correlates with 5-ASA levels, and predicts an individual’s risk of mesalamine non-adherence.METHODS:Prospective observational study. Urinary salicylates (by colorimetry) and 5-ASA (by liquid chromatography and tandem-mass spectrometry) were measured in a random urine sample at baseline in patients and controls. Mesalamine adherence was quantified by patient self-reports at enrollment and pharmacy refills of mesalamine over 6 months.RESULTS:A total of 93 patients with UC taking mesalamine maintenance therapy were prospectively enrolled from the clinic. Random urine salicylate levels (by colorimetry) were highly correlated with urine 5-ASA metabolite levels (by mass spectrometry; R2=0.9). A random urine salicylate level above 15 mg/dl distinguished patients who had recently taken mesalamine from controls (area under the curve value 0.9, sensitivity 95%, specificity 77%). A significant proportion of patients (27%) who self-identified as “high adherers” by an adherence questionnaire (Morisky Medication Adherence Scale-8) had random levels of urine salicylate below this threshold. These patients were at higher risk of objectively measured non-adherence to mesalamine over the subsequent 6 months (RR: 2.7, 95% CI: 1.1-7.0).CONCLUSIONS:A random urine salicylate level measured in the clinic can identify patients who have not recently taken mesalamine, and who are at higher risk of longitudinal non-adherence. This test could be used to screen patients who may warrant interventions to improve adherence and prevent disease relapse.Am J Gastroenterol advance online publication, 8 January 2013; doi:10.1038/ajg.2012.419.

Concepts: Measurement, Urinalysis, Salicylate sensitivity, Urine, Sulfasalazine, Crohn's disease, Mesalazine, Ulcerative colitis


The confirmation by GC/C/IRMS of the exogenous origin of pseudo-endogenous steroids from human urine samples requires extracts of adequate purity. A strategy based on HPLC sample purification prior to the GC/C/IRMS analysis of human urinary endogenous androgens (i.e. testosterone, androsterone and/or androstenediols), is presented. A method without any additional derivatization step is proposed, allowing to simplify the urine pretreatment procedure, leading to extracts free of interferences permitting precise and accurate IRMS analysis, without the need of correcting the measured delta values for the contribution of the derivatizing agent. The HPLC extracts were adequately combined to both reduce the number of GC/C/IRMS runs and to have appropriate endogenous reference compounds (ERC; i.e. pregnanediol, 11-keto-etiocholanolone) on each GC-IRMS run. The purity of the extracts was assessed by their parallel analysis by gas chromatography coupled to mass spectrometry, with GC conditions identical to those of the GC/C/IRMS assay. The method has been validated according to ISO17025 requirements (within assay precision below 0.3‰(13)C delta units and between assay precision below 0.6‰(13)C delta units for most of the compounds investigated) fulfilling the World Anti-Doping Agency requirements.

Concepts: Urinalysis, Analytical chemistry, Mass spectrometry, Accuracy and precision, World Anti-Doping Agency, Gas chromatography, Chromatography, High performance liquid chromatography


Glycol ethers are a class of semi-volatile substances used as solvents in a variety of consumer products like cleaning agents, paints, cosmetics as well as chemical intermediates. We determined 11 metabolites of ethylene and propylene glycol ethers in 44 urine samples of German residents (background level study) and in urine samples of individuals after exposure to glycol ethers during cleaning activities (exposure study). In the study on the background exposure, methoxyacetic acid and phenoxyacetic acid (PhAA) could be detected in each urine sample with median (95th percentile) values of 0.11mgL(-1) (0.30mgL(-1)) and 0.80mgL(-1) (23.6mgL(-1)), respectively. The other metabolites were found in a limited number of samples or in none. In the exposure study, 5-8 rooms were cleaned with a cleaner containing ethylene glycol monobutyl ether (EGBE), propylene glycol monobutyl ether (PGBE), or ethylene glycol monopropyl ether (EGPE). During cleaning the mean levels in the indoor air were 7.5mgm(-3) (EGBE), 3.0mgm(-3) (PGBE), and 3.3mgm(-3) (EGPE), respectively. The related metabolite levels analysed in the urine of the residents of the rooms at the day of cleaning were 2.4mgL(-1) for butoxyacetic acid, 0.06mgL(-1) for 2-butoxypropionic acid, and 2.3mgL(-1) for n-propoxyacetic acid. Overall, our study indicates that the exposure of the population to glycol ethers is generally low, with the exception of PhAA. Moreover, the results of the cleaning scenarios demonstrate that the use of indoor cleaning agents containing glycol ethers can lead to a detectable internal exposure of residents.

Concepts: Urinalysis, Arithmetic mean, Diol, Background radiation, Median, Ethylene glycol, Glycol ethers, Propylene glycol


Cases of poisoning by p-phenylenediamine (PPD) are detected sporadically. Recently an article on the development and validation of a LC-MS/MS method for the detection of PPD and its metabolites, N-acetyl-p-phenylenediamine (MAPPD) and N,N-diacetyl-p-phenylenediamine (DAPPD) in blood was published. In the current study this method for detection of these compounds was validated and applied to urine samples. The analytes were extracted from urine samples with methylene chloride and ammonium hydroxide as alkaline medium. Detection was performed by LC-MS/MS using electrospray positive ionization under multiple reaction-monitoring mode. Calibration curves were linear in the range 5-2000 ng/mL for all analytes. Intra- and inter-assay imprecisions were within 1.58-9.52% and 5.43-9.45% respectively, for PPD, MAPPD and DAPPD. Inter-assay accuracies were within -7.43 and 7.36 for all compounds. Lower limit of quantification was 5 ng/mL for all analytes. The method, which complies with the validation criteria, was successfully applied to the analysis of PPD, MAPPD and DAPPD in human urine samples collected from clinical and postmortem cases.

Concepts: Standard, Scientific method, Urinalysis, PH, Validation, Ammonia


: For patients who receive opioids or benzodiazepines, urine drug tests shed some light on the question of whether patients take their medicines as directed. How often do patients prescribed these drugs fall short? A commercial laboratory’s review of 144,535 urine samples found a high prevalence of disagreement between what clinic staff reported on laboratory requisitions and what was detected in the urine. Before concluding that most patients fail to take opioids and benzodiazepines correctly, we should take into account that urine tests sent to national laboratories reflect a skewed subset of patients who receive prescriptions. Additionally, laboratory requisitions prepared by office staff are not likely to perfectly reflect what is prescribed. Nevertheless, this report by McClure et al reminds us that urine drug test results will frequently diverge from what clinicians expect. Urine tests convey a signal requiring interpretation followed by careful, patient-centered decisions.

Concepts: Urine, Urinalysis, Drug test


Lung cancer is unusually common among non-smoking women in Southeastern Asia but the causes of this frequently fatal disease are not well understood. Several epidemiology studies indicate that inhalation of fumes from high temperature Chinese style cooking with a wok may be a cause. Only one previous study investigated uptake of potential toxicants and carcinogens by women who cook with a wok. We enrolled three-hundred twenty-eight non-smoking women from Singapore for this study. Each provided a spot urine sample and answered a questionnaire concerning their cooking habits and other factors. The urine samples were analyzed by liquid chromatography-tandem mass spectrometry for mercapturic acid metabolites of acrolein (3-hydroxypropylmercapturic acid), crotonaldehyde (3-hydroxy-1-methylpropylmercapturic acid), and benzene (S-phenylmercapturic acid), accepted biomarkers of uptake of these toxic and carcinogenic compounds. We observed statistically significant effects of wok cooking frequency on levels of 3-hydroxypropylmercapturic acid and 3-hydroxy-1-methylpropylmercapturic acid, but not S-phenylmercapturic acid. Women who cooked greater than 7 times per week had a geometric mean of 2600 (95% CI, 2189-3090) pmol/mg creatinine 3-hydroxypropylmercapturic acid compared to 1901 (95% CI, 1510-2395) pmol/mg creatinine when cooking less than once per week (P for trend 0.018). The corresponding values for 3-hydroxy-1-methylpropylmercapturic acid were 1167 (95% CI, 1022-1332) and 894 (95% CI, 749-1067) pmol/mg creatinine (P for trend 0.008). We conclude that frequent wok cooking leads to elevated exposure to the toxicants acrolein and crotonaldehyde, but not benzene. Kitchens should be properly ventilated to decrease exposure to potentially toxic and carcinogenic fumes produced during Chinese style wok cooking.

Concepts: Liquid chromatography-mass spectrometry, Urinalysis, Benzene, Water, Cooking, Epidemiology, Carcinogen, Cancer