Spot urine protein creatinine ratio compared with dipstick proteinuria as a primary screening tool for renal disease in a community setting

Background Although, the use of manual dipstick urinalysis for proteinuria has been a common practice, the Kidney Disease Improving Global Outcomes (KDIGO) guideline on screening for chronic renal disease least advocate it use. Besides, several studies have assessed the performance of dipstick urinary in screening for proteinuria to be inaccurate, unreliable with a poor predictive values. The goal of this study was to determine and compare the presence of significant proteinuria (SP) in high-risk African children using the spot urine protein creatinine ratio (UPr/UCr) as a primary screening tool besides dipstick proteinuria screening. Methods This cross-sectional study involved 1,316 apparently healthy children recruited through a multi-stage sampling technique in Ogbomoso land, Nigeria. We performed a dipstick urinalysis on early-morning urine samples. Urinary protein content was determined using a turbidimetric method and Jaffe’s reaction to measure the urinary creatinine concentration. Statistical analysis was performed using the IBM Statistical Package for Social Sciences (SPSS)TM, Version 23.0 for Windows. Results The prevalence of SP using spot UPr/UCr (≥ 0.2) and dipstick proteinuria screening (≥1+) were 18% and 0.8%, respectively (p<0.001). Of the 224 subjects determined to have SP using UPr/UCr, the females (140; 20.1%) had a higher proportion compared to males (84; 15.4% -p=0.032). Nephrotic range proteinuria was detected in nine out of 10 subjects (90%) using UPr/UCr but in only three out of ten (30%) using the urinary dipstick method. The biserial correlation coefficient (r= 0.092; p=0.001) and inter-rater-agreement (Cohen’s Kappa = 0.01) were poor, and the McNemar’s test result was (p<0.001). Conclusion The UPr/UCr ratio technique appeared to perform better than dipstick urinalysis as a primary screening tool for renal disease. Hence, it may be adopted for early detection of SP as a kidney disease marker especially among the high risk population.

Proteinuria in hospitalised internal medicine adult patients

RationaleDipstick proteinuria may be a sign of a renal disorder, false-positive or associated with acute disease, and consequently, transient in hospitalised patients.ObjectiveTo assess (a) the prevalence of proteinuria in hospitalised patients; (b) its association with estimated glomerular filtration rate (eGFR), findings known to cause false-positive test results and indicators of acute disease and (c) the need for follow-up after discharge.Setting and participantsAll patients who had a dipstick urinalysis on admission to medical wards of a 400-bed regional hospital in 2018–2019.Outcome variableProteinuria.Independent variables(a) Other findings on dipstick urinalysis; (b) patients’ age, gender, presence of urinary catheter and eGFR and (c) white blood cell count (WBC) and fever.ResultsOf 22 329 patients, 6609 (29.6%) had urinalysis. Of those, 2973 patients (45.0%) had proteinuria of ≥+1 (≥0.30 g/L). The variables independently associated with proteinuria were other dipstick findings known to cause false-positive test results, elevated WBC, fever on presentation, presence of a urethral catheter and a low eGFR. eGFR alone was a poor predictor of proteinuria (c-stat 0.62); however, addition of the remaining independent variables to the model significantly improved its predictive ability (c-stat 0.80).ConclusionsDipstick proteinuria is common in hospitalised patients. Although weakly associated with eGFR, proteinuria is mainly associated with confounding factors that may result in false-positive test results. The need for follow-up of proteinuria after discharge has questionable clinical utility and its high frequency would entail a considerable cost.

Validity of dipstick urinalysis for predicting urinary tract infection in febrile children aged 2-12 years in a tertiary care centre, South Kerala

Background: Urinary tract infection (UTI) warrants an early accurate diagnosis in children. Use of rapid diagnostic tests like urine dipstick and microscopy was found to be economical and effective. There is lack of sufficient studies on rapid diagnostic tests in developing countries like India. This study looked at the single as well as combination of parameters that provided maximum sensitivity and specificity, providing a better diagnostic criterion in detecting UTI. The objective was to assess the diagnostic validity of urinary dipstick in the diagnosis of UTI in comparison with urinary culture.Methods: This cross-sectional diagnostic evaluation study was conducted in a tertiary care centre in Southern Kerala. Total of 75 children between the age group of 2 years to 12 years who attended the paediatric OPD with the clinical features of UTI were included in this study. Two urine samples were obtained in sterile containers. The first urine sample was assessed with dipstick and the second sample was sent for culture to confirm the UTI. The results obtained were analysed using SPSS software.Results: Using culture as gold standard, the results for nitrate alone had lower sensitivity at 69.69%, specificity at 90.4%. The results for LE (LE) alone had higher sensitivity at 81.8%, specificity at 80.95% and the results for combined urine dipstick had higher sensitivity at 84.8% than individual nitrite and LE. The combined positive predictive value (PPV) was lower than individual nitrite and LE 75.6%. The combined negative predictive value (NPV) was higher than individual LE and nitrite at 86.8%.Conclusions: Dipstick urinalysis alone may not be a completely adequate screening tool for UTI. Since urine dipstick test has high sensitivity it can be used as a bedside tool in detecting UTI in children.

Risk Factors Associated With Abnormal Urinalysis in Children

Background: Targeted urinalysis has been suggested to improve screening efficiency in adults. However, there is no well-defined target population in children yet, with limited information on the risk factors for urinalysis abnormalities.Methods: Children from infants to 17 years old were randomly selected. Dipstick urinalysis was initially performed. Among those who were abnormal, a repeat dipstick or dipstick with microscopic urinalysis was performed for confirmation.Results: In total, 70,822 children were included, with 37,866 boys and 32,956 girls. Prevalence of abnormal urinalysis was 4.3%. Age was significantly associated with abnormal urinalysis, with the highest prevalence among 12–14-year-olds. Girls were 2.0 times more likely to exhibit abnormalities. Compared with children whose guardians had a college degree or higher, those whose guardians had a high school degree or lower had a higher likelihood of abnormalities. Geographic location was also associated with abnormal results.Conclusion: Girls, children aged 12–14 years old, and children whose guardians had a low educational level and children in certain geographic locations were significantly associated with abnormal urinalysis. Identification of children at high risk would contribute to targeted urinalysis screening.

Availability and Affordability of Kidney Health Laboratory Tests around the Globe

<b><i>Background:</i></b> Kidney disease is a major global public health problem, and laboratory testing of kidney health measures is essential for diagnosis and monitoring. The availability and affordability of kidney health laboratory tests across countries has not been systematically described. <b><i>Methods:</i></b> The International Society of Nephrology (ISN), in partnership with leaders of a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference, surveyed a representative subset of ISN-Global Kidney Health Atlas (ISN-GKHA) respondents from April to June 2020. We assessed the association between country gross national income (GNI) per capita and laboratory testing availability and affordability. <b><i>Results:</i></b> Of 33 regional expert nephrologists invited, 24 (73%) responded, representing all 10 ISN regions around the world. Availability of kidney health laboratory tests was as follows: serum Cr (100%), serum cystatin C (67%), urine albumin (96%), urine Cr (100%), and dipstick urinalysis (100%). Median (IQR) reimbursement values in international dollars were as follows: serum Cr Int$ 6.61 (3.42–8.84), serum cystatin C Int$ 31.51 (17.36–46.25), urine albumin Int$ 10.22 (5.90–15.42), urine Cr Int$ 7.50 (1.66–8.84), and dipstick urinalysis Int$ 6.26 (2.56–8.40). Reimbursement values did not differ significantly by World Bank income group or by GNI per capita. <b><i>Conclusion:</i></b> There was widespread availability of kidney health laboratory tests and substantial variation in reimbursement values. To achieve meaningful progress across nations in mitigating the growth of kidney disease, access to affordable diagnostic technology is essential. Our results are highly relevant to policymakers and researchers as countries increasingly consider national strategies for kidney disease detection and management.

Asymptomatic Bacteuria among Healthy Cohort Using Dipstick Urinalysis from a Tertiary Health Care Facility in South East Nigeria

Dipstick urinalysis is a simple and cost effective method for screening of urinary abnormalities, thus enabling early detection and prompt management of renal pathologies. The aim of the study was to determine the pattern of urinalysis profile among apparently healthy cohorts using medical doctors of Nnamdi Azikiwe University Teaching Hospital. One hundred (100) medical doctors aged 20 to 50 years were selected through convenience sampling in a descriptive cross sectional study from August 20, 2020 to September 10, 2020. Ninety-One (91%) had their urine tested with dipstick test strips by Wellkang Ltd. Abnormal urinary findings occurred in 48 (52.8%) of the subjects which were blood 5 (5.50%), glucose 8 (8.80%), protein 15 (16.50%), nitrite 10 (11.00%), leucocyte 6 (6.60%) and Ascorbic acid 4 (4.40%). The prevalence of urine abnormality was higher in the 25-30year age group (48.4%), though not statistically significant (P>0.05). No significant association existed between pH and urine abnormality (p=0.5). No significant association existed between specific gravity and urine abnormality (p=0.5). It was concluded that the prevalence of urine abnormalities was significantly high (52.8%) with proteinuria and (11.0%) nitrites being the commonest abnormalities. Routine dipstick urinalysis is a cheap and simple method for early identification of urine abnormalities in apparently healthy cohorts using medical doctors and a positive dipstick test for proteinuria should prompt further evaluation for the presence of kidney disease. It is recommended that Urinalysis should be instituted as a routine test for medical doctors in hospitals because of its importance in disease surveillance.

Urinalysis and Urine Culture

Key Points Bagged specimens are adequate for dipstick urinalysis but not urine culture. Routine screening urinalysis for asymptomatic patients is not recommended. Proteinuria, hematuria, glucosuria, and positive nitrites and/or leukocyte esterase on dip urinalysis requires further workup.