scholarly journals Comparison of 24-hour versus random urine samples for determination and quantification of Bence Jones protein in a South African population

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Ashandree Reddy ◽  
Nadine Rapiti ◽  
Verena Gounden
Keyword(s):  
Treatment Response ◽  
South African ◽  
Urine Samples ◽  
Urine Collection ◽  
Creatinine Ratio ◽  
Sample Collection ◽  
Bence Jones Protein ◽  
Estimation Equations ◽  
Monitor Treatment Response ◽  
African Patients

Background: The International Myeloma Working Group and College of American Pathologists recommend a 24-h urine collection to determine the Bence Jones protein (BJP) excretion level for monitoring treatment response in patients with multiple myeloma (MM). There are several issues related to sample collection and the method is prone to inaccuracy.Objective: This study compared measured 24-h to random urine collections for the quantitation of BJP in a South African population.Methods: Sixty-six patients with MM submitted random urine samples with their routine 24-h urine collection from April 2016 – March 2018. Measured 24-h urine BJP was compared to two estimated 24-h BJP excretions calculated as follows: Estimation 1 (E1): Estimated 24-h BJP (mg/24 h) = Urine BJP/Creatinine ratio (mg/mmol) × 10. Estimation 2 (E2): Estimated 24-h BJP (mg/24 h) = Urine BJP/Creatinine ratio (mg/mmol) × 15 mg/kg for women or × 20 mg/kg for men.Results: Correlation of estimation equations E1 and E2 to the measured 24-h urine BJP was 0.893. Patients showed no difference in classification of treatment response using either the E1 or E2 estimation equations when compared to the measured 24-h urine BJP results.Conclusion: This study demonstrates that the estimated 24-h BJP shows a high degree of correlation with the measured 24-h BJP and can likely be used to monitor treatment response in South African patients with MM.

Twelve-Hour Urine Collection Can Be Utilized to Estimate 24-Hour Total Urinary Nitrogen in Critically Trauma Patients

2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S1-S1
Author(s):  
Hsuan-Chieh Liao ◽  
Grant O’Keefe ◽  
Fred Woo ◽  
Lisa Lawrence ◽  
Geoffrey Baird
Keyword(s):  
Correlation Coefficients ◽  
Urine Samples ◽  
Trauma Patients ◽  
Urine Collection ◽  
Sample Collection ◽  
Icu Patients ◽  
Nitrogen Levels ◽  
Significant Difference ◽  
Regression Slopes ◽  
Urinary Nitrogen

Abstract Patients suffering from trauma, burns, and sepsis are frequently in a hypermetabolic state, and as the majority of urinary nitrogen comes from amino acid metabolism, the determination of total urinary nitrogen (TUN) provides an accurate measurement of all nitrogen excreted in urine and can be used as an indicator of catabolic stress. To evaluate whether time of collection influences the performance of TUN test, 12-hour urine specimens were collected from ICU trauma patients and the 12-hour results were correlated with results from 24-hour collections. Two consecutive 12-hour urine samples were collected (06:00-18:00 hours and 18:00-06:00 hours) from surgical ICU patients. Total urinary nitrogen levels were measured in each 12-hour sample, as well as in a pooled sample (24 hours). Pyrochemiluminescence was used to determine TUN level on an Antek 9000N elemental analyzer. In this approach, the urine sample is completely oxidized at high temperature in a quartz pyrotube. Nitrogen is converted to nitric oxide (·NO), then mixed with O3 (ozone) to form nitrogen dioxide (NO2). Light is emitted and specific wavelengths between 650 and 900 nm were measured in a photomultiplier tube. The measured chemiluminescent emission is specific and proportional to the amount of nitrogen in the sample. Fifty 12-hour urine samples from 16 patients were collected. One patient was excluded from the study due to acute renal injury during the collection period. There was no significant observed circadian effect on measured TUN. The 12-hour TUN (g/total volume) was multiplied by 2 to compare to 24-hour TUN for statistical analysis. There was strong correlation between either day or night 12-hour TUN and corresponding pooled 24-hour TUN, with correlation coefficients ranging from 0.93 to 0.98 and regression slopes ranging from 0.98 to 1.01. No statistically significant difference was found between the 12-hour TUN and 24-hour TUN approaches. A 12-hour TUN collection was overall highly predictive of 24-hour TUN collection and has the advantage of convenience of sample collection and improved clinical efficiency. Serial 12-hour urine collection is therefore preferred for monitoring nitrogen balance and adjusting protein intake for critically ill ICU patients.

A pilot study on the utility of reduced urine collection frequency protocols for the assessment of reproductive hormones in adolescent girls

2017 ◽  
Vol 30 (10) ◽  
Author(s):  
Heather C.M. Allaway ◽  
Esther M. John ◽  
Theresa H. Keegan ◽  
Mary Jane De Souza
Keyword(s):  
Menstrual Cycle ◽  
Adolescent Girls ◽  
Cycle Length ◽  
Ovarian Function ◽  
Reproductive Hormones ◽  
Urine Samples ◽  
Urine Collection ◽  
Sample Collection ◽  
Three Samples ◽  
Two Samples

AbstractBackground:The objectives of this study were to assess the feasibility of and compliance to collecting urine samples in pre- and postmenarcheal girls and to determine if a less than daily collection frequency was sufficient for assessing ovarian function.Methods:Twenty-five postmenarcheal girls (11–17 years) collected samples using either a two or a three samples/week protocol during one menstrual cycle. Exposure and mean estrone-1-glucuronide (E1G) and pregnanediol glucuronide concentrations were calculated, and evidence of luteal activity (ELA) was evaluated. Sixteen premenarcheal girls (8–11 years) collected one sample/month for six consecutive months. Samples were analyzed for E1G concentration. Participant compliance was calculated using dates on the urine samples and paper calendars.Results:Participants collecting three samples/week were more compliant to the protocol than those collecting two samples/week (83.6%±2.6% vs. 66.8%±6.6%; p=0.034). There were no differences (p>0.10) regarding paper calendar return (81.8%±12.2% vs. 92.9%±7.1%), recording menses (55.6%±17.6% vs. 92.3%±7.7%) or sample collection (88.9%±11.1% vs. 84.6%±10.4%) between the two protocols. The average cycle length was 30.5±1.3 days and 32% of cycles had ELA. The premenarcheal girls were 100% compliant to the protocol. Only 68.8% of participants returned the paper calendar and 81.8% of those participants recorded sample collection. The average E1G concentration was 15.9±3.8 ng/mL.Conclusions:Use of a less than daily collection frequency during one menstrual cycle in postmenarcheal, adolescent girls is feasible and provides informative data about ovarian function. Collection of one sample/month in premenarcheal girls is feasible and detects the expected low E1G concentrations. Alternate strategies to the use of a paper calendar should be considered.

scholarly journals 1886. N1,N12-Diacetylspermine as Potential Urinary Biomarker to Monitor Treatment Response and Bacterial Load in Pulmonary Tuberculosis

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S53-S53
Author(s):  
Qianjing (Jenny) Xia ◽  
Myung Hee Lee ◽  
Kyu Rhee ◽  
Flonza Isa
Keyword(s):  
Treatment Response ◽  
Treatment Efficacy ◽  
High Performance ◽  
Bacterial Load ◽  
Treatment Success ◽  
Sample Collection ◽  
Tb Treatment ◽  
Experimental Drug ◽  
Potential Biomarker ◽  
Monitor Treatment Response

Abstract Background Adequate control of the global tuberculosis (TB) burden is limited by a lack of accurate measures of treatment efficacy. Current gold standard relies on sputum cultures, which often lag weeks behind time of sample collection. Previous studies have identified urinary N1,N12-diacetylspermine (DiAcSpm) as a potential biomarker of active pulmonary TB (ATB). We aimed to quantify urinary DiAcSpm in participants being treated for ATB and identify its relationship to treatment response. Methods Longitudinal urine samples were obtained from two separate cohorts of participants treated for ATB. Cohort one consisted of 34 successfully treated ATB cases with urine collected at weeks 0, 2, 4, 8, 17, 26, and 52. Cohort two consisted of 35 ATB cases under two treatment arms: one arm was successfully treated with the standard therapy of rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE), and the other arm received an experimental drug, which was later found to be ineffective against ATB. Urine from cohort two was collected at days 0, 2, 4, and 14. All samples were blinded, randomized, normalized to osmolality and urinary creatinine, and analyzed using high-performance liquid chromatography-mass spectrometry. DiAcSpm concentrations were further tested using ELISA. Results Using linear-mixed modeling that adjusted for age, sex, and participant weight, we found that urinary DiAcSpm significantly decreased by week 2 of successful treatment in both cohorts (P < 0.0001). DiAcSpm levels remained unchanged in the ineffective experimental drug group (cohort two), significantly differentiating treatment success and failure by day 14 (P < 0.0001). Additionally, concentrations of urinary DiAcSpm positively correlate with sputum mycobacterial burden (P = 0.0002).These findings were consistent across both methods of detection. Conclusion Our results suggest that urinary concentrations of DiAcSpm correlate with TB treatment outcome and mycobacterial disease burden, and have the potential to serve as an early biomarker of TB treatment efficacy. Disclosures All Authors: No reported Disclosures.

Diurnal variation in urine nitrogen and creatinine concentrations from lactating cows grazing ryegrass-dominant pasture in autumn and late spring–summer

2017 ◽  
Vol 57 (7) ◽  
pp. 1297 ◽  
Author(s):  
G. P. Cosgrove ◽  
A. Jonker ◽  
K. A. Lowe ◽  
P. S. Taylor ◽  
D. Pacheco
Keyword(s):  
Diurnal Variation ◽  
Urine Volume ◽  
Late Spring ◽  
Urine Samples ◽  
Creatinine Ratio ◽  
Sample Collection ◽  
N Losses ◽  
Total N ◽  
Once Daily ◽  
N Concentration

In dairy production systems based on grazed pasture, urine patches are the main source of nitrogen (N) losses via leaching and gaseous emission pathways. The volume and N concentration of urine influences the amount of N in a urine patch. We conducted systematic urine sampling to determine the diurnal variation in concentrations of N and creatinine (a proxy for urine volume), and the N : creatinine ratio, to identify the sampling required for accurately estimating the daily mean concentrations of N and creatinine. Nine groups (n = 6) of multiparous Friesian and Friesian × Jersey cows in autumn (220 ± 26 days-in-milk, milked twice daily) and nine groups (n = 6) in late spring–summer (228 ± 24 days-in-milk, milked once daily) were sequentially withdrawn from the farm herd at approximately weekly intervals and each group was offered a fresh allocation of ryegrass-dominant pasture twice daily after milking for 3 days (including at the equivalent time in the afternoon in late spring–summer when they were milked once daily). For each of the 18 different groups of cows, individual urine samples were collected on Day 3 at 1100 hours, 1500 hours (afternoon milking), 1800 hours and 0700 hours (the following morning milking), and, subsequently, analysed for total N and creatinine concentrations. In autumn, urine-N concentrations were higher (P = 0.0002) at 1800 hours (5.8 g N/L) than they were at 1500 hours or 0700 hours (mean of 4.2 g N/L). In late spring–summer, the concentrations were higher (P < 0.001) at 1100 hours (8.0 g N/L) than they were at 1500 hours, 1800 hours or 0700 hours (mean of 6.3 g N/L). The urine N : creatinine ratio was 214 mol/mol in autumn and 148 mol/mol in late spring–summer, but did not vary among sampling times during the day. The highest concentrations of N were in urine samples collected ~3 h post-allocation of fresh feed when cows had grazed actively and consumed the majority of the herbage available. For accurate estimates of the daily mean urine N concentration, sample collections should be timed to encompass this diurnal variation. For the N : creatinine ratio, which was more stable through the day, the timing of sample collection is less important for estimating a daily mean.

scholarly journals Urinary Microbiota; Which Non-invasive Urine Collection Method Should We Use?

2021 ◽  
Author(s):  
Muhammed Selcuk Ozer ◽  
Hüseyin Alperen Yıldız ◽  
Canet Incir ◽  
Dogan Deger ◽  
Ozan Bozkurt ◽  
...  
Keyword(s):  
Urine Sample ◽  
Statistical Significance ◽  
Wilcoxon Test ◽  
Urine Samples ◽  
Urine Collection ◽  
Sample Collection ◽  
Collection Method ◽  
Significant Difference ◽  
Urinary Microbiota ◽  
Bacterial Groups

Objective: The aim of this study is establish the optimal non- invaszive urine sample collection method for the microbiota studies. Methodology: 12 men with bladder carcinoma underwent first voided and midstream urine collection. Urine samples were analyzed by using V3-V4 regions of bacterial 16s ribosomal RNAs. Bacterial groups with relative abundance above 1% were analyzed in first voided urine and midstream urine samples at phylum, class, order, and family level. At the genus level, all of the identified bacterial groups’ relative abundances were analyzed. The statistical significance (p<0.05) of differences between first voided and midstream urine sample microbiota were evaluated using the Wilcoxon test. Results: According to analysis, 8 phyla, 14 class, 23 orders, 39 families, and 29 different genera were identified in the first voided and the midstream urine samples. Statistical differences were not identified between first voided and mid-stream urine samples of all bacteria groups except the Clostridiales at order level (p:0.04) and Clostridia at class level (p:0.04). Conclusions: Either first voided or midstream urine samples can be used in urinary microbiota studies as we determined that there is no statistically significant difference between them regarding the results of 16s ribosomal RNA analysis. What’s known? According to widespread acceptance, first voided urine and midstream urine should be collected separately for standard microbiologic evaluation. What’s new? We found that there is no exact statistically significant difference between two collection methods even on microbiota analysis. We believe that either first voided or midstream uyrine samples can be used in urinary microbiota studies.

Twenty-Four–Hour Bence-Jones Protein Determinations: Can We Ensure Accuracy?

2011 ◽  
Vol 135 (8) ◽  
pp. 1048-1051 ◽  
Author(s):  
Jennifer S Kaplan ◽  
Gary L Horowitz
Keyword(s):  
Urine Samples ◽  
Creatinine Ratio ◽  
Inclusion Criteria ◽  
Bence Jones Protein ◽  
Creatinine Excretion ◽  
Urine Creatinine ◽  
Light Chain Disease ◽  
Variation Range ◽  
Clinically Significant ◽  
Current Guidelines

Context.—Light chain disease represents 15% to 20% of cases of multiple myeloma. Current guidelines recommend monitoring these patients with 24-hour urine collections. Objective.—To determine the reliability of 24-hour urine collections in assessing the amount of Bence-Jones protein (BJP). Design.—We included all patients from our institution from 2003 through 2008 with BJP who had more than four 24-hour urine collections. We compared BJP excretion calculated from the submitted 24-hour collection with BJP excretion calculated by normalizing the collection to that patient's mean 24-hour creatinine excretion. We also looked at differences in serial values with these 2 methods. In addition, we evaluated the feasibility of using random urine samples to determine BJP excretion. Results.—A total of 14 patients with 135 24-hour urine collections met our inclusion criteria. The 24-hour urine creatinine excretion for each patient, which should be reasonably constant, varied considerably (coefficient of variation range 12%–30%). Differences in the 2 methods of calculating BJP excretion ranged from −1588 to 2315 mg/d. Among a total of 121 serial 24-hour measurements, the differences were clinically significant in 37 (30%). Among a total of 23 random urine samples from 11 of these patients submitted within 10 days of a 24-hour collection, the estimated BJP excretion appeared to be accurate in at least 18 (78%). Conclusions.—Twenty-four–hour urine collections for BJP are, in practice, often misleading. At a minimum, one should verify that the 24-hour creatinine excretion is accurate. In addition, it may be possible to use the protein/creatinine ratio from random urine samples to determine 24-hour BJP excretion.

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