FlowUTI: An interactive web-application for optimizing the use of flow cytometry as a screening tool in urinary tract infections.

Due to the high prevalence of patients attending with urinary tract infection (UTI) symptoms, the use of flow-cytometry as a rapid screening tool to avoid unnecessary cultures is becoming a widely used system in clinical practice. However, the recommended cut-points applied in flow-cytometry systems differ substantially among authors, making it difficult to obtain reliable conclusions. Here, we present FlowUTI, a shiny web-application created to establish optimal cut-off values in flow-cytometry for different UTI markers, such as bacterial or leukocyte counts, in urine from patients with UTI symptoms. This application provides a user-friendly graphical interface to perform robust statistical analysis without a specific training. Two datasets are analyzed in this manuscript: one composed of 204 urine samples from neonates and infants (≤3 months old) attended in the emergency department with suspected UTI; and the second dataset including 1174 urines samples from an elderly population attended at the primary care level. The source code is available on GitHub (https://github.com/GuillermoMG-HUVR/Microbiology-applications/tree/FlowUTI/FlowUTI). The web application can be executed locally from the R console. Alternatively, it can be freely accessed at https://covidiario.shinyapps.io/flowuti/. FlowUTI provides an easy-to-use environment for evaluating the efficiency of the urinary screening process with flow-cytometry, reducing the computational burden associated with this kind of analysis.

Alterations in the molecular composition of COVID-19 patient urine, detected using Raman spectroscopic/computational analysis.

We developed and tested a method to detect COVID-19 disease, using urine specimens. The technology is based on Raman spectroscopy and computational analysis. It does not detect SARS-CoV-2 virus or viral components, but rather a urine 'molecular fingerprint', representing systemic metabolic, inflammatory, and immunologic reactions to infection. We analyzed voided urine specimens from 46 symptomatic COVID-19 patients with positive real time-polymerase chain reaction (RT-PCR) tests for infection or household contact with test-positive patients. We compared their urine Raman spectra with urine Raman spectra from healthy individuals (n = 185), peritoneal dialysis patients (n = 20), and patients with active bladder cancer (n = 17), collected between 2016-2018 (i.e., pre-COVID-19). We also compared all urine Raman spectra with urine specimens collected from healthy, fully vaccinated volunteers (n = 19) from July to September 2021. Disease severity (primarily respiratory) ranged among mild (n = 25), moderate (n = 14), and severe (n = 7). Seventy percent of patients sought evaluation within 14 days of onset. One severely affected patient was hospitalized, the remainder being managed with home/ambulatory care. Twenty patients had clinical pathology profiling. Seven of 20 patients had mildly elevated serum creatinine values (>0.9 mg/dl; range 0.9-1.34 mg/dl) and 6/7 of these patients also had estimated glomerular filtration rates (eGFR) <90 mL/min/1.73m2 (range 59-84 mL/min/1.73m2). We could not determine if any of these patients had antecedent clinical pathology abnormalities. Our technology (Raman Chemometric Urinalysis-Rametrix®) had an overall prediction accuracy of 97.6% for detecting complex, multimolecular fingerprints in urine associated with COVID-19 disease. The sensitivity of this model for detecting COVID-19 was 90.9%. The specificity was 98.8%, the positive predictive value was 93.0%, and the negative predictive value was 98.4%. In assessing severity, the method showed to be accurate in identifying symptoms as mild, moderate, or severe (random chance = 33%) based on the urine multimolecular fingerprint. Finally, a fingerprint of 'Long COVID-19' symptoms (defined as lasting longer than 30 days) was located in urine. Our methods were able to locate the presence of this fingerprint with 70.0% sensitivity and 98.7% specificity in leave-one-out cross-validation analysis. Further validation testing will include sampling more patients, examining correlations of disease severity and/or duration, and employing metabolomic analysis (Gas Chromatography-Mass Spectrometry [GC-MS], High Performance Liquid Chromatography [HPLC]) to identify individual components contributing to COVID-19 molecular fingerprints.

Altered kidney function induced by SARS-CoV-2 infection and acute kidney damage markers predict survival outcomes of COVID-19 patients: a prospective pilot study.

BACKGROUND: Literature with regard to coronavirus disease 2019 (COVID-19) associated morbidities and the risk factors for death are still emerging. In this study, we investigated the presence of kidney damage markers and their predictive value for survival among hospitalized subjects with COVID-19. METHODS: Forty-seven participants was included and grouped as: 'COVID-19 patients before treatment', 'COVID-19 patients after treatment', 'COVID-19 patients under treatment in intensive care unit (ICU)', and 'controls'. Kidney function tests and several kidney injury biomarkers were compared between the groups. Cumulative rates of death from COVID-19 were determined using the Kaplan-Meier method. The associations between covariates including kidney injury markers and death from COVID-19 were examined, as well. RESULTS: Serum creatinine and cystatin C levels, urine Kidney Injury Molecule-1 (KIM-1)/creatinine ratio, and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), CKD-EPI cystatin C, and CKD-EPI creatinine-cystatin C levels demonstrated significant difference among the groups. The most significant difference was noted between the groups 'COVID-19 patients before treatment' and 'COVID-19 patients under treatment in ICU'. Advancing age, proteinuria, elevated serum cystatin C, and urine KIM-1/creatinine ratio were all significant univariate correlates of death (p < 0.05, for all). However, only elevated urine KIM-1/creatinine ratio retained significance in an age, sex, and comorbidities adjusted multivariable Cox regression (OR 6.11; 95% CI: 1.22-30.53; p = 0.02), whereas serum cystatin C showing only a statistically non-significant trend (OR 1.42; 95% CI: 0.00-2.52; p = 0.09). CONCLUSIONS: Our findings clearly demonstrated the acute kidney injury related to COVID-19. Moreover, urine KIM-1/creatinine ratio was associated with COVID-19 specific death.

Urine sediment findings were milder in patients with COVID-19-associated renal injuries than in those with non-COVID-19-associated renal injuries.

BACKGROUND: Acute renal injury is an important complication of coronavirus disease 2019 (COVID-19). Both COVID-19-specific mechanisms, such as damage to the renal parenchyma by direct infection, and non-specific mechanisms, such as the pre-renal injury factors, have been proposed to be involved in COVID-19-associated renal injuries. In this study, we aimed to elucidate the characteristics of COVID-19-associated renal injuries, focusing mainly on urine sediment findings. METHODS: We compared the urine sediment findings and their associations with renal functions or urinary clinical parameters between subjects with COVID-19 and subjects without COVID-19 with acute renal injuries. RESULTS: We found that the number of urine sediment particles and the levels of N-acetyl-ß-D-glucosaminidase, α1-microglobulin, liver type fatty acid-binding protein, and neutrophil gelatinase-associated lipocalin were associated with the severity of COVID-19. In addition, we observed that the number of granular casts, epithelial casts, waxy casts, and urinary chemical marker levels were lower in the subjects with COVID-19 than subjects without COVID-19 with acute renal injuries when the subjects were classified according to their renal function. CONCLUSIONS: These results suggest that pre-renal injury factors might be largely involved in the pathogenesis of COVID-19-associated renal injuries compared with non-COVID-19-associated renal injuries arising from surgery or sepsis.

Using dipstick urinalysis to predict development of acute kidney injury in patients with COVID-19.

BACKGROUND: Acute kidney injury (AKI) is a common complication in patients hospitalized with COVID-19 and may require renal replacement therapy (RRT). Dipstick urinalysis is frequently obtained, but data regarding the prognostic value of hematuria and proteinuria for kidney outcomes is scarce. METHODS: Patients with positive severe acute respiratory syndrome-coronavirus 2 (SARS-CoV2) PCR, who had a urinalysis obtained on admission to one of 20 hospitals, were included. Nested models with degree of hematuria and proteinuria were used to predict AKI and RRT during admission. Presence of Chronic Kidney Disease (CKD) and baseline serum creatinine were added to test improvement in model fit. RESULTS: Of 5,980 individuals, 829 (13.9%) developed an AKI during admission, and 149 (18.0%) of those with AKI received RRT. Proteinuria and hematuria degrees significantly increased with AKI severity (P < 0.001 for both). Any degree of proteinuria and hematuria was associated with an increased risk of AKI and RRT. In predictive models for AKI, presence of CKD improved the area under the curve (AUC) (95% confidence interval) to 0.73 (0.71, 0.75), P < 0.001, and adding baseline creatinine improved the AUC to 0.85 (0.83, 0.86), P < 0.001, when compared to the base model AUC using only proteinuria and hematuria, AUC = 0.64 (0.62, 0.67). In RRT models, CKD status improved the AUC to 0.78 (0.75, 0.82), P < 0.001, and baseline creatinine improved the AUC to 0.84 (0.80, 0.88), P < 0.001, compared to the base model, AUC = 0.72 (0.68, 0.76). There was no significant improvement in model discrimination when both CKD and baseline serum creatinine were included. CONCLUSIONS: Proteinuria and hematuria values on dipstick urinalysis can be utilized to predict AKI and RRT in hospitalized patients with COVID-19. We derived formulas using these two readily available values to help prognosticate kidney outcomes in these patients. Furthermore, the incorporation of CKD or baseline creatinine increases the accuracy of these formulas.

Using social media to crowdsource collection of urine samples during a national pandemic.

The COVID-19 pandemic and subsequent lockdown had a substantial impact on normal research operations. Researchers needed to adapt their methods to engage at-home participants. One method is crowdsourcing, in which researchers use social media to recruit participants, gather data, and collect samples. We utilized this method to develop a diagnostic test for Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). Participants were recruited via posts on popular social-media platforms, and enrolled via a website. Participants received and returned a mail kit containing bladder symptom surveys and a urine sample cup containing room-temperature preservative. Using this method, we collected 1254 IC/BPS and control samples in 3 months from all 50 United States. Our data demonstrate that crowdsourcing is a viable alternative to traditional research, with the ability to reach a broad patient population rapidly. Crowdsourcing is a powerful tool for at-home participation in research, particularly during the lockdown caused by the COVID-19 pandemic.

Proteomic and metabolomic profiling of urine uncovers immune responses in patients with COVID-19.

The utility of the urinary proteome in infectious diseases remains unclear. Here, we analyzed the proteome and metabolome of urine and serum samples from patients with COVID-19 and healthy controls. Our data show that urinary proteins effectively classify COVID-19 by severity. We detect 197 cytokines and their receptors in urine, but only 124 in serum using TMT-based proteomics. The decrease in urinary ESCRT complex proteins correlates with active SARS-CoV-2 replication. The downregulation of urinary CXCL14 in severe COVID-19 cases positively correlates with blood lymphocyte counts. Integrative multiomics analysis suggests that innate immune activation and inflammation triggered renal injuries in patients with COVID-19. COVID-19-associated modulation of the urinary proteome offers unique insights into the pathogenesis of this disease. This study demonstrates the added value of including the urinary proteome in a suite of multiomics analytes in evaluating the immune pathobiology and clinical course of COVID-19 and, potentially, other infectious diseases.

Evaluation of Renal Function in COVID-19 Patients by Using Urinalysis Following the Administration of Vancomycin.

BACKGROUND: The aim of this study was to evaluate renal function by urinalysis in COVID-19 patients following the administration of vancomycin. METHODS: A retrospective observational study was performed between October 2020 and January 2021, during which time patients were hospitalized in the Prince Mohammed Bin Abdulaziz Hospital in Riyadh, Saudi Arabia. The patients were free of kidney disease. Urinalysis was performed by an automated laboratory system, and the collected results were based upon age, gender, diabetic status, whether the patients had received vancomycin, the mortality rate, and the urinalysis panel including coinfection by bacteria and yeast. RESULTS: A total of 227 patients were included in this study, 147 (64.75%) of whom were male and 80 (35.25%) of whom were female; 54.63% were diabetic, 11.89% were prediabetic, and 33.48% were non-diabetic patients. Proteinuria, hematuria, glycosuria, coinfection, and ketonuria were detected among all participants within the study group, specifically among diabetic patients. The mortality rate was 16.2% among the study group; 6.6% had re-ceived vancomycin, and 9.6% had not received vancomycin. No significant correlation was found between nephrotoxicity and abnormalities in the urine and the mortality rate among members of our study group. CONCLUSIONS: Proteinuria, hematuria, glycosuria, ketonuria, and coinfection were common among members of our study group, especially in the diabetic group. Urinalysis abnormalities were less frequent in the vancomycin group than in the others, except the prediabetic group. No correlation between mortality and vancomycin was identified.

Renal-Clearable Molecular Probe for Near-Infrared Fluorescence Imaging and Urinalysis of SARS-CoV-2.

Despite the importance of rapid and accurate detection of SARS-CoV-2 in controlling the COVID-19 pandemic, current diagnostic methods are static and unable to distinguish between viable/nonviable virus or directly reflect viral replication activity. Real-time imaging of protease activity specific to SARS-CoV-2 can overcome these issues but remains lacking. Herein, we report a near-infrared fluorescence (NIRF) activatable molecular probe (SARS-CyCD) for detection of SARS-CoV-2 protease in living mice. The probe comprises a hemicyanine fluorophore caged with a protease peptide substrate and a cyclodextrin unit, which function as an NIRF signaling moiety and a renal-clearable enabler, respectively. The peptide substrate of SARS-CyCD can be specifically cleaved by SARS-CoV-2 main protease (Mpro), resulting in NIRF signal activation and liberation of the renal-clearable fluorescent fragment (CyCD). Such a design not only allows sensitive detection of Mpro in the lungs of living mice after intratracheal administration but also permits optical urinalysis of SARS-CoV-2 infection. Thus, this study presents an in vivo sensor that holds potential in preclinical high-throughput drug screening and clinical diagnostics for respiratory viral infections.

Could urinary kidney injury molecule-1 be a good marker in subclinical acute kidney injury in mild to moderate COVID-19 infection?

PURPOSE: To evaluate urinary kidney injury molecule-1 (uKIM-1), which is a proximal tubule injury biomarker in subclinical acute kidney injury (AKI) that may occur in COVID-19 infection. METHODS: The study included proteinuric (n = 30) and non-proteinuric (n = 30) patients diagnosed with mild/moderate COVID-19 infection between March and September 2020 and healthy individuals as a control group (n = 20). The uKIM-1, serum creatinine, cystatin C, spot urine protein, creatinine, and albumin levels of the patients were evaluated again after an average of 21 days. RESULTS: The median (interquartile range) uKIM-1 level at the time of presentation was 246 (141-347) pg/mL in the proteinuric group, 83 (29-217) pg/mL in the non-proteinuric group, and 55 (21-123) pg/mL in the control group and significantly high in the proteinuric group than the others (p < 0.001). Creatinine and cystatin C were significantly higher in the proteinuric group than in the group without proteinuria, but none of the patients met the KDIGO-AKI criteria. uKIM-1 had a positive correlation with PCR, non-albumin proteinuria, creatinine, cystatin C, CRP, fibrinogen, LDH, and ferritin, and a negative correlation with eGFR and albumin (p < 0.05). In the multivariate regression analysis, non-albumin proteinuria (p = 0.048) and BUN (p = 0.034) were identified as independent factors predicting a high uKIM-1 level. After 21 ± 4 days, proteinuria regressed to normal levels in 20 (67%) patients in the proteinuric group. In addition, the uKIM-1 level, albuminuria, non-albumin proteinuria, and CRP significantly decreased. CONCLUSIONS: Our findings support that the kidney is one of the target organs of the COVID-19 and it may cause proximal tubule injury even in patients that do not present with AKI or critical/severe COVID-19 infection.

Mass urine sugar testing to tackle post-COVID mucormycosis epidemic in India-MUSTARD concept.

BACKGROUND: Post-Covid mucormycosis is associated with very high morbidity and reasonably high mortality. The three main causes seem to be covid infection, excessive steroid usage and uncontrolled diabetes. METHODS: Of the three risk factors causing post-Covid mucormycosis, the only risk factor which can be modified quickly is uncontrolled diabetes. Checking urine-sugar levels of susceptible population asymptomatic for mucormycosis can be done rapidly and at a relatively low cost. Urine sugar positive persons can then be investigated and managed for uncontrolled diabetes. RESULTS: None CONCLUSIONS: Mass urine sugar testing to assess and regulate diabetes(MUSTARD) can help identify and manage uncontrolled diabetes in populations with high prevalence of diabetes.

Carbohydrate binding module-fused antibodies improve the performance of cellulose-based lateral flow immunoassays.

Since the pandemic outbreak of Covid-19 in December 2019, several lateral flow assay (LFA) devices were developed to enable the constant monitoring of regional and global infection processes. Additionally, innumerable lateral flow test devices are frequently used for determination of different clinical parameters, food safety, and environmental factors. Since common LFAs rely on non-biodegradable nitrocellulose membranes, we focused on their replacement by cellulose-composed, biodegradable papers. We report the development of cellulose paper-based lateral flow immunoassays using a carbohydrate-binding module-fused to detection antibodies. Studies regarding the protein binding capacity and potential protein wash-off effects on cellulose paper demonstrated a 2.7-fold protein binding capacity of CBM-fused antibody fragments compared to the sole antibody fragment. Furthermore, this strategy improved the spatial retention of CBM-fused detection antibodies to the test area, which resulted in an enhanced sensitivity and improved overall LFA-performance compared to the naked detection antibody. CBM-assisted antibodies were validated by implementation into two model lateral flow test devices (pregnancy detection and the detection of SARS-CoV-2 specific antibodies). The CBM-assisted pregnancy LFA demonstrated sensitive detection of human gonadotropin (hCG) in synthetic urine and the CBM-assisted Covid-19 antibody LFA was able to detect SARS-CoV-2 specific antibodies present in serum. Our findings pave the way to the more frequent use of cellulose-based papers instead of nitrocellulose in LFA devices and thus potentially improve the sustainability in the field of POC diagnostics.

Minimal Change Disease Following the Pfizer-BioNTech COVID-19 Vaccine.

We report on the development of minimal change disease (MCD) with nephrotic syndrome and acute kidney injury (AKI), shortly after first injection of the BNT162b2 COVID-19 vaccine (Pfizer-BioNTech). A 50-year-old previously healthy man was admitted to our hospital following the appearance of peripheral edema. Ten days earlier, he had received the first injection of the vaccine. Four days after injection, he developed lower leg edema, which rapidly progressed to anasarca. On admission, serum creatinine was 2.31 mg/dL and 24-hour urinary protein excretion was 6.9 grams. As kidney function continued to decline over the next days, empirical treatment was initiated with prednisone 80 mg/d. A kidney biopsy was performed and the findings were consistent with MCD. Ten days later, kidney function began to improve, gradually returning to normal. The clinical triad of MCD, nephrotic syndrome, and AKI has been previously described under a variety of circumstances, but not following the Pfizer-BioNTech COVID-19 vaccine. The association between the vaccination and MCD is at this time temporal and by exclusion, and by no means firmly established. We await further reports of similar cases to evaluate the true incidence of this possible vaccine side effect.

The impact of COVID-19 on routine patient care from a laboratory perspective.

BACKGROUND: Globally, few studies have examined the effect of the COVID-19 pandemic on routine patient care and follow-up. OBJECTIVES: To evaluate the effect of the COVID-19 response on biochemical test requests received from outpatient departments (OPDs) and peripheral clinics serviced by the National Health Laboratory Service Chemical Pathology Laboratory at Tygerberg Hospital, Cape Town, South Africa (SA). Request volumes were used as a measure of the routine care of patients, as clinical information was not readily available. METHODS: A retrospective audit was conducted. The numbers of requests received from OPDs and peripheral clinics for creatinine, glycated haemoglobin (HbA1c), lipid profiles, thyroid-stimulating hormone (TSH), free thyroxine, free tri-iodothyronine (fT3), serum and urine protein electrophoresis, serum free light chains and neonatal total serum bilirubin were obtained from 1 March to 30 June for 2017, 2018, 2019 and 2020. RESULTS: The biggest impact was seen on lipids, creatinine, HbA1c, TSH and fT3. The percentage reduction between 1 March and 30 June 2019 and between 1 March and 30 June 2020 was 59% for lipids, 64% for creatinine and HbA1c, 80% for TSH and 81% for fT3. There was a noteworthy decrease in overall analyte testing from March to April 2020, coinciding with initiation of level 5 lockdown. Although an increase in testing was observed during June 2020, the number of requests was still lower than in June 2019. CONCLUSIONS: This study, focusing on the short-term consequences of the SA response to the COVID-19 pandemic, found that routine follow-up of patients with communicable and non-communicable diseases was affected. Future studies are necessary to evaluate the long-term consequences of the pandemic for these patient groups.

Considering the harms of our habits: The reflexive urine drug screen in opioid use disorder treatment.

The COVID-19 pandemic has led to abrupt changes in the delivery of substance use treatment, notably the adoption of telehealth services and a departure from mandatory urine drug screens (UDS). Amid current circumstances, the UDS, which had evolved to signal a "successful" recovery, no longer seems feasible, safe, or necessary. Even prior to the pandemic, the UDS had notable drawbacks, including sending a message of mistrust and hierarchy, potentially causing psychological trauma, and incentivizing falsification. Nonetheless, certain patients may state that they depend on the UDS for motivation or structure while some providers may rely on it to discover which patients are struggling. While a combination of self-report and UDS is generally regarded as the strongest measure of substance use among patients, our experiences caring for patients without the results of the UDS during the COVID-19 pandemic have forced us to examine the use of other measures to define a successful recovery. Complete abstinence may not be the goal for all patients and those who achieve abstinence may have additional goals worth supporting. While the UDS will likely be incorporated back into our treatment plans, we suggest unseating it as the centerpiece of substance use care and discovering additional methods of measuring our patients' outcomes in less traumatizing and more patient-centered ways.

Urine abnormalities predict acute kidney injury in COVID-19 patients: An analysis of 110 cases in Chennai, South India.

BACKGROUND AND AIMS: Renal involvement in Covid-19 infection is varied and can affect glomeruli, tubules, interstitium and can cause acute kidney injury (AKI). AKI is a strong predictor of mortality. Routine urinalysis gives an insight into the renal pathology of the patient. We studied the incidence of urinary abnormalities in hospitalised Covid-19 patients and analysed their impact on development of AKI and mortality. METHODS: Information on 110 hospitalised patients with confirmed Covid-19 was retrospectively collected and analysed. The demographic data such as age, gender, comorbid conditions such as diabetes mellitus, the need for dialysis and laboratory data such as urine for albumin, glucose, RBC and WBC, and serum creatinine were collected. The diagnosis of AKI was based on the KDIGO criteria. The outcomes studied were development of AKI and hospital mortality. RESULTS: Urine abnormalities were seen in 71% of the patients. Proteinuria in 58.2%, haematuria in 17.3%, pyuria in 8.2% of patients and concurrent proteinuria and haematuria was seen in 13.6% of patients. AKI was seen in 28.2% of patients and hospital mortality was 24.5%. AKI was strongly associated with mortality. Proteinuria and haematuria were good predictors of development of AKI, more strongly when they occurred concurrently (p < 0.01). CONCLUSION: Our results suggest that urine analysis is a simple test, which can be used to predict development of AKI and mortality and may be used for risk stratification of Covid-19 patients, especially in low resource settings.

Evidence of increased Fentanyl use during the COVID-19 pandemic among opioid agonist treatment patients in Ontario, Canada.

BACKGROUND: Amid the opioid crisis, the health care system is restructuring to prevent and treat COVID-19. Individuals in opioid agonist treatment (OAT) are uniquely challenged because of disruption to treatment, medication diversion, and isolation during the pandemic. METHODS: Between January and September 2020, we utilized the electronic medical record from a chain of 67 opioid agonist treatment clinics in Ontario, Canada, to examine routinely collected urine drug screen results of patients in opioid agonist treatment by Public Health Units. RESULTS: We present evidence of a 108% increase in the percentage of fentanyl positive urine drug screens from April to September (p< 0.001). During the same period, health regions in northern and southwestern Ontario, areas with a high concentration of rural communities, have seen the most notable increase in the percent of fentanyl positive urine drug screen results. CONCLUSION: The use of fentanyl increased by 108% among OAT patients in Ontario during the COVID 19 pandemic. We argue that the persistent increase of fentanyl exposure over time, specifically in the OAT population, suggests that reduced monitoring may decrease OAT's effectiveness and negatively impact patient outcomes.

Biosafety Level 2 cabinet UV-C light exposure of sports antidoping human urine samples does not affect the stability of selected prohibited substances.

The current study examined the stability of several antidoping prohibited substances analytes in urine after 15-min exposure to UV-C light in a Biosafety Level 2 cabinet. The urine matrices were exposed within the original antidoping bottles with the aim to destroy DNA/RNA and possible SARS CoV-2. The analytes small molecules Phase I and Phase II metabolites and peptides, in total 444, endogenous, internal standards, and prohibited substances, pH, and specific gravity in urine were studied. The accredited analytical methods were used by Anti-Doping Laboratory Qatar for the comparison of data of the same urine samples analyzed with and without UV-C exposure. In the study conditions, no problems of stability were detected in the substances spiked in the urine samples exposed in the UV-C irradiation.