Performance Evaluation of Urine Osmolality Measurement on Sysmex UF-5000 and the Effect of Molecules and Particles in Urine.

BACKGROUND: Urine osmolality determines the concentration ability of the kidney. Therefore, it is used to assess the body's hydration status, electrolyte levels, and acid-base disturbances. We aimed to evaluate the analytical performance of osmolality measurement of the Sysmex UF-5000 (UF-5000), to examine the effect of different molecules and particles in the urine on the osmolality measurement. METHODS: Complete urinalysis and conductivity-based osmolality analysis with UF-5000 and osmolality analysis with Advanced® Model 3320 Micro-Osmometer (AI-3320) by freezing point reduction method were performed in the urine samples. Samples were grouped as negative, glucosuria, proteinuria, hematuria, pyuria, crystalluria, and urobilinogen. RESULTS: Total impressions were calculated as < 5% and accuracy values were < 1.66% in both analyzers. The regression equation was found to be y = -12.54 + 0.956x and the relative difference between the analyzers was 8.7% in 586 samples. When patients with Glucose > 2+ were excluded the regression equation of 507 samples was found as y = 5.10 + 0.948x and the relative difference was 4.6%. The percentages of samples with a difference greater than the allowable difference were 18.8%, 11.6%, 35.9%, 13.7%, 18.7%, and < 12.2% in all samples, all samples without glucosuria > 2+, glucosuria, glucosuria < 3+, proteinuria, and other subgroups, respectively. CONCLUSIONS: Considering the good accessibility of the automated routine complete urine analyzer, UF-5000 can be considered to determine whether urine osmolality is within reference or should be measured by methods based on colligative properties. Thus, referral of patients to a clinic that uses the colligative measurement method may be used more effectively.

Comparison of urine bisphenol A levels in transient tachypnea of the newborn and healthy newborns.

BACKGROUND: To investigate the relationship between neonatal urine bisphenol A (BPA) levels and the prevalence and prognosis of transient tachypnea of the newborn (TTN). METHODS: This prospective study was conducted between January and April 2020 in the Neonatal Intensive Care Unit (NICU) of Gaziantep Cengiz Gökçek Obstetrics and Pediatric Hospital. The study group consisted of patients diagnosed with TTN and the control group was made up of healthy neonates housed together with their mothers. Urine samples were collected from the neonates within the first 6 hours postnatally. RESULTS: Urine BPA levels and urine BPA/creatinine levels were statistically higher in the TTN group (P < 0.005). The receiver operating characteristic (ROC) curve analysis determined the cut-off value of urine BPA for TTN to be 1.18 µg/L (95% confidence interval [CI]: 0.667-0.889, sensitivity: 78.1%, and specificity: 51.5%) and the cut-off value of urine BPA/creatinine to be 2.65 µg/g (95% CI: 0.727-0.930, sensitivity: 84.4%, and specificity: 66.7%). Furthermore, the ROC analysis indicated that the cut-off value of BPA for neonates requiring invasive respiratory support was 15.64 µg/L (95% CI: 0.568-1.000, sensitivity: 83.3%, and specificity: 96.2%) and the cut-off value for BPA/creatinine was 19.10 µg/g (95% CI: 0.777-1.000, sensitivity: 83.3%, and specificity: 84.6%) among the TTN patients. CONCLUSIONS: BPA and BPA/creatinine values were higher in the urine of newborns diagnosed with TTN which is a fairly common cause of NICU hospitalization, in samples collected within the first 6 hours after birth, which may be a reflection of intrauterine factors.

Reducing sulfide and methane production in gravity sewer sediments through urine separation, collection and intermittent dosing.

Sulfide and methane production are a major concern in sewer management. Many solutions with the use of chemicals have been proposed yet incurring huge costs. Here, this study reports an alternative solution to reduce sulfide and methane production in sewer sediments. This is achieved through integration of urine source separation, rapid storage, and intermittent in situ re-dosing into a sewer. Based on a reasonable capacity of urine collection, an intermittent dosing strategy (i.e. 40 min per day) was designed and then experimentally tested using two laboratory sewer sediment reactors. The long-term operation showed that the proposed urine dosing in the experimental reactor effectively reduced sulfidogenic and methanogenic activities by 54% and 83%, compared to those in the control reactor. In-sediment chemical and microbial analyses revealed that the short-term exposure to urine wastewater was effective in suppressing sulfate-reducing bacteria and methanogenic archaea, particularly within a surface active zone of sediments (0-0.5 cm) likely attributed to the biocidal effect of urine free ammonia. Economic and environmental assessments indicated that the proposed urine approach can save 91% in total costs, 80% in energy consumption and 96% in greenhouse gas emissions compared to the conventional use of chemicals (including ferric salt, nitrate, sodium hydroxide, and magnesium hydroxide). These results collectively demonstrated a practical solution without chemical input to improve sewer management.

Phenotype of Urine Sediment Cells in Patients with Bladder Cancer.

Phenotype of urine sediment cells were studied in patients with bladder cancer depending on the cancer stage and recurrence prognosis. In T1N0M0 stage, the number of lymphocytes decreased, in T2N0M0 stage, the most pronounced shift was an increase in the number of erythrocytes. Irrespectively of the disease stage, we observed increased number of innate immunity cells and cells that inhibit antitumor immunity in the composition of the leukocyte fraction of urine sediment cells. At T1N0M0 stage, the epithelial-endothelial fraction was characterized by increased content of cells expressing CD13 marker (responsible for tumor growth and metastasis) and reduced number of cells expressing CD15 marker (responsible for intercellular adhesion). In patients developing relapse of bladder cancer, the number of lymphocytes was decreased in urine sediment cells and the number of epithelial and endothelial cells expressing CD13 marker was increased.

Machine Learning Prediction of Urine Cultures in Primary Care.

Context: Antibiotics for suspected urinary tract infection (UTI) is appropriate only when an infection is present. Urine culture is definitive but takes >1 day to result. A machine learning urine culture predictor was recently devised for Emergency Department (ED) patients but requires use of urine microscopy ("NeedMicro" predictor), which is not routinely available in primary care (PC). Objective: To adapt this predictor to use only features available in primary care and determine if predictive accuracy generalizes to the primary care setting. We call this the "NoMicro" predictor. Study Design and Analysis: Multicenter, retrospective, observational, cross-sectional analysis. Machine learning predictors were trained using extreme gradient boosting, artificial neural networks, and random forests. Models were trained on the ED dataset and were evaluated on both the ED dataset (internal validation) and the PC dataset (external validation). Setting: United States (US) academic medical centers emergency department and family medicine clinic. Population Studied: 80387 (ED, previously described) and 472 (PC, newly curated) US adults. Instrument: Physicians performed retrospective chart review. The primary outcome extracted was pathogenic urine culture growing ≥100,000 colony forming units. Predictor variables included age; gender; dipstick urinalysis nitrites, leukocytes, clarity, glucose, protein, and blood; dysuria; abdominal pain; and history of UTI. Outcome Measures: Predictor overall discriminative performance (receiver operating characteristic area under the curve, ROC-AUC), performance statistics (e.g., sensitivity, negative predictive value, etc.), and calibration. Results: The "NoMicro" model performs similarly to the "NeedMicro" model in internal validation on the ED dataset: NoMicro ROC-AUC 0.862 (95% CI: 0.856-0.869) vs. NeedMicro 0.877 (95% CI: 0.871-0.884). External validation on the primary care dataset also yielded high performance (NoMicro ROC-AUC 0.850 [95% CI: 0.808-0.889]), despite being trained on Emergency Department data. Simulation of a hypothetical, retrospective clinical trial suggests the NoMicro model could be used to avoid antibiotic overuse by safely withhold antibiotics in low-risk patients. Conclusions: The hypothesis that the NoMicro predictor generalizes to both PC and ED contexts is supported. Prospective trials to determine the real-world impact of using the NoMicro model to reduce antibiotic overuse are appropriate.

Magnetic solid phase extraction of Sunitinib malate in urine samples assisted with mixed hemimicelle and spectrophotometric detection.

The mixed hemimicelle-based solid phase extraction method using the coated sodium dodecyl sulfate by magnetic iron oxide nanoparticles as adsorbent was developed for extraction and determination of Sunitinib malate in real samples prior to determination by UV-Visible spectrophotometry. For the characterization of synthesized nanoparticles, Fourier transform infrared spectroscopy, and scanning electron microscopy was used. The influences of different factors affecting the extraction efficiency of Sunitinib malate, including the pH, the adsorbent amount, the volume and eluent type, the amount of the surfactant, the ionic strength, extraction, and desorption time, were investigated. At the optimized conditions, a good linearity with correlation coefficients of 0.998 and 0.999 was obtained over the concentration ranges of 1-22 and 1-19 µg/mL for water and urine samples, in order. The good recoveries of 97% and 99% and also, the limits of detection equal with 0.9, and 0.8 µg/mL for water and urine samples were enhanced, respectively. These results demonstrate that mixed hemimicelle solid phase extraction is a fast, efficient, economical and selective sample preparation method for the extraction and determination of Sunitinib malate in different water and urine sample solutions.

[The risk prediction value of paraquat poisoning dose, urine protein and myocardial enzymes].

Objective: To explore the value of paraquat (PQ) intake, urine protein and myocardial enzyme indexes in judging the prognosis of patients with acute PQ poisoning. Methods: From September to December 2021, all 201 patients with acute PQ poisoning admitted to Guangzhou Twelfth People's Hospital from January 2010 to December 2019 were selected as the research objects. Based on follow-up results 60 days after poisoning, the research objects were divided into survival group (n=78) and death group (n=123) . The differences in information about poisoning, treatment plan, PQ intake, urine protein, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase between the two groups of patients were compared and analyzed. Logistic regression and Cox regression were used to analyze the correlation between poisoning outcome and PQ intake, urine protein and myocardial enzymes. ROC curve and principal component analysis were used to explore high-efficiency indicators for predicting the outcome of acute PQ poisoning. Results: The PQ intake[50 (20, 100) ml], urine protein (total rank 15570.50) , creatine kinase[ (336.36±261.96) U/L], creatine kinase isoenzyme[ (43.91±43.74) U/L], lactate dehydrogenase [ (346.01±196.50) U/L], α-hydroxybutyrate dehydrogenase content[ (271.23±11.92) U/L] of patients in the death group were all higher than the survival group[15 (10, 20) ml, 4730.50, (187.78±178.06) U/L, (18.88±15.50) U/L, (190.92±60.50) U/L, (152.60±48.34) U/L, respectively] (P<0.05) . The outcome of acute PQ poisoning was positively correlated with PQ intake, urine protein, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase (P<0.05) . Multivariate logistic regression and multivariate Cox regression analysis showed that creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase and α-hydroxybutyrate dehydrogenase was positively correlated with the prognosis of patients with acute PQ poisoning (P<0.05) . ROC curve analysis and principal component analysis showed that the combined indexes of PQ intake, urine protein and myocardial enzymes had the highest efficacy and weight in judging the prognosis of patients (AUC=0.91, weight coefficient=0.19, sensitivity=0.76, specificity=0.89) . When the combined score was ≥4, the probability of accurately predicting the death of patients was as high as 91% (positive predictive value=0.91) . Conclusion: PQ intake, urine protein combined with creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase has high value in predicting the prognosis of patients with acute PQ poisoning.

Concentrating stabilized human urine using eutectic freeze crystallization for liquid fertilizer production.

Resource recovery from source-separated urine can be used to produce fertilizers and provide a more sustainable alternative to mineral fertilizers. Reverse osmosis can be used to remove up to 70% of the water in urine that has been stabilized with Ca(OH)2 and pre-treated with air bubbling. However, further water removal is limited because of membrane scaling and equipment operating pressure limitations. A novel hybrid eutectic freeze crystallization (EFC) and RO system was investigated as a method to concentrate human urine, whilst simultaneously crystallizing salt and ice under EFC conditions. A thermodynamic model was used to predict the type of salts that would crystallize, their associated eutectic temperatures, and how much additional water removal was required (using freeze crystallization) to reach eutectic conditions. This innovative work showed that at eutectic conditions, Na2SO4∙10H2O crystallizes simultaneously with ice in both real and synthetic urine, thus providing a new method to concentrate human urine for liquid fertilizer production. A theoretical mass balance of a hybrid RO-EFC process, including ice washing and recycle streams, showed that 77% of the urea and 96% of the potassium could be recovered with a 95% water removal. The final liquid fertilizer would have a composition of 11.5% N and 3.5% K, and 3.5 kg of Na2SO4∙10H2O could be recovered from 1000 kg of urine. Over 98% of the phosphorus would be recovered as calcium phosphate during the urine stabilization step. A hybrid RO-EFC process would require 60 kWh m-3 of energy, which is substantially less than other concentration methods.

[Detection and identification of urinary crystals using an automated urine particle analyzer coupled with a digital particle imaging device]. / Détection et identification de cristaux dans les urines à l'aide d'un analyseur de cytologie urinaire couplé à un dispositif d'imagerie numérique.

Polarized light microscopy (POM) remains the gold standard for crystalluria analysis. However, such method is time consuming and requires well-trained staff. Here, to address this issue, we tested the Sysmex UF-4000 analyzer coupled to a UD10 module as an automated flow cytometry-digital particle imaging workflow to assess (i) the ability of the system to detect and identify the crystals species and (ii) the quality of the images provided by the UD-10 module (n = 40) for each urine sample analyzed. First, systematic analysis of 76 samples by POM and the UF-4000/UD-10 analyzer showed that only attentive examination of the 40 photos was able to confidently detect crystalluria-positive samples with no misses and thus serve to discriminate positive-test crystalluria from negative-test crystalluria. These first results were confirmed by sensitivity analysis and the negative predictive value calculated on 200 samples for the results provided by the UF-4000 (39% and 46%) and after examination of the 40 UD-10 photos (100% for the both values). Digital images can therefore serve to screen crystalluria without missing crystals. A part of samples were treated by POM whereas it was not necessary (positive predictive value: 78%). Finally, we compared the crystal identification performances of the Sysmex UF4000/UD10 workflow and the 'gold standard' POM method on 131 urine samples containing crystals. Only calcium oxalate dihydrate crystals were identified by the Sysmex UF-4000. A close examination of the digital photographs enabled exact identification of crystals in 84.7% of the samples, suggesting however that POM is still require as soon as crystals are observed on the photographs. We conclude that a SYSMEX UF-4000 coupled with a UD-10 module can be used in practice with close examination of the photographs to discriminate positive crystalluria from negative crystalluria.

Accuracy of the Sysmex UF-5000 analyzer for urinary tract infection screening and pathogen classification.

The screening performance of urine flow cytometry parameters (e.g., white blood cell and bacteria) for urinary tract infection (UTI) has been widely recognized. The majority of previous studies, however, investigated the screening performance of Sysmex UF-1000i urine flow cytometer. This study aimed to investigate the screening performance of Sysmex UF-5000 analyzer, a third-generation urinary flow cytometer, for UTI and its novel parameter named Gram flag for discriminating gram-positive and negative pathogens. Urine specimens sent to the clinical microbiology laboratory of our hospital for bacterial culture between September 13, 2021, and November 15, 2021, were prospectively and consecutively collected. The Sysmex UF-5000 analyzer was used to determine urine white blood cell (WBC) and bacteria simultaneously. A chemical strip was used to assess urine nitrate. UTI was defined as positive urine bacterial culture > 104 CFU /ml. The receiver operating characteristics (ROC) curve, nomogram, decision tree, and decision curve were used to determine the screening performance of urine WBC, nitrate, and bacterial. A total of 246 UTIs and 425 non-UTIs were enrolled. The areas under the ROC curve (AUCs) for WBC and bacterial were 0.74 and 0.86, respectively. The decision curve showed that urine bacteria had a higher benefit than WBC. The nomogram indicated that urine bacterial had the largest effect on the probability of UTI. The sensitivity and specificity of the decision tree were 0.69 and 0.95, respectively. The flag of Gram-negative had a positive predictive value (PPV) of 0.93 in patients with urine bacteria > 1367 /µl. Therefore, we conclude that urine bacteria determined by the Sysmex UF-5000 had higher screening performance and greater benefit than WBC. The decision tree can be used to improve the screening performance of routine urinary parameters. The flag of Gram-negative is a reliable indicator to confirm gram-negative bacteria infection in UTI patients.

Live births from urine derived cells.

Here we report urine-derived cell (UDC) culture and subsequent use for cloning which resulted in the successful development of cloned canine pups, which have remained healthy into adulthood. Bovine UDCs were used in vitro to establish comparative differences between cell sources. UDCs were chosen as a readily available and noninvasive source for obtaining cells. We analyzed the viability of cells stored in urine over time and could consistently culture cells which had remained in urine for 48hrs. Cells were shown to be viable and capable of being transfected with plasmids. Although primarily of epithelial origin, cells were found from multiple lineages, indicating that they enter the urine from more than one source. Held in urine, at 4°C, the majority of cells maintained their membrane integrity for several days. When compared to in vitro fertilization (IVF) derived embryos or those from traditional SCNT, UDC derived embryos did not differ in total cell number or in the number of DNA breaks, measured by TUNEL stain. These results indicate that viable cells can be obtained from multiple species' urine, capable of being used to produce live offspring at a comparable rate to other cell sources, evidenced by a 25% pregnancy rate and 2 live births with no losses in the canine UDC cloning trial. This represents a noninvasive means to recover the breeding capacity of genetically important or infertile animals. Obtaining cells in this way may provide source material for human and animal studies where cells are utilized.

Evaluation of Women With a Positive Urine Cytology and no Demonstrable Disease in the Urinary Tract.

Urinary cytology is indispensable both for the evaluation of gross hematuria and surveillance of patients with urothelial neoplasms. A positive urine cytology usually indicates the presence of urothelial carcinoma somewhere in the urinary tract. However, in women, it may also signal urothelial carcinoma involvement of the lower gynecologic tract or be the presenting sign for a primary cancer of the lower gynecologic tract or rectum. Guidelines for the evaluation of women with a positive cytology and normal urinary tract are lacking. We present a review of the current literature with case scenarios to bring clinicians attention to this diagnostic dilemma.

Optimizing reflex urine cultures: Using a population-specific approach to diagnostic stewardship.

BACKGROUND: Clinicians and laboratories routinely use urinalysis (UA) parameters to determine whether antimicrobial treatment and/or urine cultures are needed. Yet the performance of individual UA parameters and common thresholds for action are not well defined and may vary across different patient populations. METHODS: In this retrospective cohort study, we included all encounters with UAs ordered 24 hours prior to a urine culture between 2015 and 2020 at 3 North Carolina hospitals. We evaluated the performance of relevant UA parameters as potential outcome predictors, including sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV). We also combined 18 different UA criteria and used receiver operating curves to identify the 5 best-performing models for predicting significant bacteriuria (≥100,000 colony-forming units of bacteria/mL). RESULTS: In 221,933 encounters during the 6-year study period, no single UA parameter had both high sensitivity and high specificity in predicting bacteriuria. Absence of leukocyte esterase and pyuria had a high NPV for significant bacteriuria. Combined UA parameters did not perform better than pyuria alone with regard to NPV. The high NPV ≥0.90 of pyuria was maintained among most patient subgroups except females aged ≥65 years and patients with indwelling catheters. CONCLUSION: When used as a part of a diagnostic workup, UA parameters should be leveraged for their NPV instead of sensitivity. Because many laboratories and hospitals use reflex urine culture algorithms, their workflow should include clinical decision support and or education to target symptomatic patients and focus on populations where absence of pyuria has high NPV.

Correlaciones entre la ingesta de sal en la dieta y la eliminación de sodio en la orina de 24 h en una muestra de población urbana de Cáceres / Correlations between dietary salt intake and 24-h urine sodium excretion in a sample of the urban population of Cáceres

Objetivo: La ingesta excesiva de sal se asocia a mayores cifras de tensión arterial y prevalencia de enfermedades cardiovasculares. La OMS recomienda consumir menos de 5 g/día de sal (equivalente a 2 g de Na+/día). Identificar alimentos y comportamientos con mayor contribución al exceso de aporte facilitaría el consejo dietético preventivo. Diseño: Estudio observacional. Sitio: Centro de Salud Urbano en Cáceres. Medidas principales: Estimamos el consumo de sal mediante dos cuestionarios de frecuencia de consumo de alimentos (CFA), uno genérico y otro con alimentos con elevado contenido en Na+, y encuesta recordatoria de 24 h. Empleamos el programa Evalfinut para la valoración nutricional de la dieta. Analizamos correlaciones entre ingesta estimada de sal y eliminación de sodio en orina de 24 h (gold standard). Resultados: El 92% de la muestra presenta consumos superiores a las recomendaciones con ingestas equivalentes a 9,5 g/día de sal (3,7 g/día de Na+). Cuando la ingesta de sodio se determina por el cociente Na+/K+, el 79,54% tiene ingestas elevadas. La eliminación de sodio sigue una tendencia ligeramente creciente con el IMC. La percepción de consumo de sal es baja, el 56,3% lo considera «adecuado»; el 32,4% añade sal a los alimentos una vez servidos. Los CFA infraestiman la ingesta de Na+ y encuestas dirigidas aportan valores más elevados. La correlación entre CFA y eliminación urinaria de Na+ es débil. Conclusión: Debemos reducir la ingesta de sal aumentando la percepción del consumo, mejorando el conocimiento sobre el contenido de sal en alimentos e identificando a pacientes diana del consejo sanitario.(AU)

Objective: Excessive salt intake is associated with higher levels of AHT and prevalence of cardiovascular diseases. WHO recommends consuming less than 5 g/day of salt (equivalent to 2 g Na+/day). Identifying foods and behaviours with greater contribution to excess intake would facilitate preventive dietary advice. Design: Observational study. Site: Urban Health Center in Cáceres. Main measurements: We estimated salt consumption using two food consumption frequency (FFQ) questionnaires, one generic and one with high Na+ content, and a 24 h follow-up survey. We use the Evalfinut program for nutritional evaluation of the diet. We analyzed correlations between estimated salt intake and 24-h urine sodium elimination (gold standard). Results: 92% of the population had consumption higher than the recommendations with intakes equivalent to 9.5 g/day of salt (3.7 g/d of Na+). When sodium intake is determined by the Na+/K+ ratio, 79.54% have high intakes. Sodium elimination follows a slightly increasing trend with BMI. The perception of salt consumption is low, 56.3% consider it “adequate”. 32.4% add salt to food once served. FFQ underestimate Na+ intake and targeted surveys provide higher values. The correlation between FFQ and Na+ urinary elimination is weak. Conclusion: We must reduce salt intake by increasing the perception of consumption, improving knowledge about the salt content in food and identifying target patients of the health council.(AU)

Urine flow acceleration in healthy children: A retrospective cohort study.

AIMS: To establish normal reference values of urine flow acceleration (Qacc ) in healthy children, as there is a lack of nomograms for normative reference values of Qacc by voided volumes in the pediatric population so far. Qacc might be an early indicator of autonomic neuropathy in children and adolescents. METHODS: Data were retrospectively collected from healthy children who underwent uroflowmetry between 1990 and 1992. Exclusion criteria were voided volume less than 20 ml, and postvoid residual more than 15%. Baseline characteristics and uroflowmetry parameters were collected from girls and boys aged between 6 and 18 years. Voided volume, voiding time, time to maximum flow rate, and maximum and average flow rates of urine were measured, and Qacc was calculated. Postvoid bladder diameter was measured by ultrasonography and converted to volume. RESULTS: Uroflowmetry parameters of 208 children (≤18 years old, 45.2% girls, mean age 9.68 ± 3.09 years) who performed 404 micturition were analyzed. Median voided volume, voiding time, time to Qmax , Qave , Qmax , Qacc , and postvoid residual volume were 130 [20-460] ml, 10 [3-56] s, 3 [1-14] s, 11.7 [2.5-36.6] ml/s, 20.5 [5-50] ml/s, 6 [0.81-25] ml/s2 , and 1.83 [0-38.62] ml, respectively. Qacc nomograms were given in centile forms for girls and boys separately, which show an inversely proportional correlation between voided volumes. CONCLUSIONS: These are the first nomograms for normative reference values of Qacc in the pediatric population (girls and boys separately) by voided volumes in centile forms. These may be useful to interpret abnormal Qacc values and diagnose lower urinary tract diseases over a wide range of voided volumes.

Sensor-based evaluation of a Urine Trap toilet in a shared bathroom.

Urine diversion in a No-Mix Toilet is a promising approach for sustainable fertilizers and reduction of the nutrient load for wastewater treatment; however, user adoption remains a challenge. This study evaluates the Urine Trap, a passive No-Mix toilet design based on the teapot effect, wherein the urine stream inlet is invisible to the user and therefore it does not impact the user experience for increased adoption. This study evaluated the nutrient separation performance of a Urine Trap flush toilet in a bathroom shared by women in two sites in India. Over three different testing periods, 841 uses of this squat plate were recorded in 50 days. Analytical measurements found 36 % separation efficiency for total nitrogen (TN). While effective, the Urine Trap under test by users did not yield a 70-80 % TN separation efficiency observed under engineering characterization. High temporal resolution data from sensors on waste collection tanks, the opening of the bathroom door, and cleansing water flow were used to gain insights into hygiene practices. The data showed a frequent habit of wetting the squat plate during physiological excretion, a hygienic practice that eases cleaning but degrades the teapot separation effect of the Urine Trap design. By using sensors, we demonstrate a method to non-invasively gain quantitative insights into hygiene practices to inform sanitation technologies deployment strategies for improved outcomes.

Performance of Sysmex UF-5000 for candiduria screening.

In this study, we tested the performance of the Sysmex UF-5000 system to detect yeast-like cell (YLC) counting to screen for candiduria. Urine samples were screened for leukocyte and yeast amount by flow cytometry and results were compared with fungal culture results. A total of 56,749 urine samples were enrolled in this study. Urine culture and urinalysis of YLC data were used to evaluate the performance of YLC in diagnosing candiduria. Different cut-off values (YLC. 5, 10, 20, 50, 100/µl) were evaluated. Youden index was used to determine the ideal cut-off value, and the highest was 0.95 with 5 YLC/µl. When the cut-off value for YLC is 5 cells/µl, 95.15% of the samples were "negative" with flow cytometry and culture (NPV:100%). In conclusion, detection of YLC by flow cytometer (Sysmex UF-5000) can be a rapid alternative method to exclude candiduria prior to urine culture.

Donnan dialysis for phosphate recovery from diverted urine.

There is a critical need to shift from existing linear phosphorous management practices to a more sustainable circular P economy. Closing the nutrient loop can reduce our reliance on phosphate mining, which has well-documented environmental impacts, while simultaneously alleviating P pollution of aquatic environments from wastewater discharges that are not completely treated. The high orthophosphate, HxPO4(3-x)-, content in source-separated urine offers propitious opportunities for P recovery. This study examines the use of Donnan dialysis (DD), an ion-exchange membrane-based process, for the recovery of orthophosphates from fresh and hydrolyzed urine matrixes. H2PO4- transport against an orthophosphate concentration gradient was demonstrated and orthophosphate recovery yields up to 93% were achieved. By adopting higher feed to receiver volume ratios, DD enriched orthophosphate in the product stream as high as ≈2.5 × the initial urine feed concentration. However, flux, selectivity, and yield of orthophosphate recovery were detrimentally impacted by the presence of SO42- and Cl- in fresh urine, and the large amount of HCO3- rendered hydrolyzed urine practically unsuitable for P recovery using DD. The detrimental effects of sulfate ions can be mitigated by utilizing a monovalent ion permselective membrane, improving selectivity for H2PO4- transport over SO42- by 3.1 × relative to DD with a conventional membrane; but the enhancement was at the expense of reduced orthophosphate flux. Critically, widely available and low-cost/waste resources with sufficiently high Cl- content, such as seawater and waste water softening regenerant rinse, can be employed to improve the economic viability of orthophosphate recovery. This study shows the promising potential of DD for P recovery and enrichment from source-separated urine.