Screening Test For Proteinuria Research Articles

Combined utilization of untimed single urine of MCP-1 and TWEAK as a potential indicator for proteinuria in lupus nephritis: A case-control study.

The aim of this study was to determine whether combined utilization of untimed single urine monocyte chemoattractant protein 1 (uMCP-1) and tumor necrosis factor (TNF)-like weak inducer of apoptosis (uTWEAK) could serve as a screening test for proteinuria in patients with lupus nephritis (LN).A case-control study that contained 39 biopsy-proven LN patients, 20 non-LN systemic lupus erythematosus (SLE) patients, and 10 healthy controls (HCs) were carried out. Correlations between uMCP-1, uTWEAK, and traditional clinical markers were analyzed by Spearman correlation test. Diagnostic values of uMCP-1, uTWEAK, and urine albumin/creatinine ratio (uACR) in the assessment of proteinuria were investigated by receiver operating characteristic (ROC) curves.Biopsy-proven LN patients showed higher levels of uMCP-1 and uTWEAK than non-LN patients. uMCP-1 and uTWEAK were elevated in renal active patients (rSLEDAI ≥4). Both uMCP-1 and uTWEAK showed significant correlation with patients' rSLEDAI, 24-hour urine proteinuria (24hr UP), and anti-double-stranded DNA (anti-dsDNA) antibodies. No correlations of these 2 biomarkers between cystatin C (Cys-C), creatinine (Cr), and blood urea nitrogen (BUN) were observed. An algorithm combining the moderate sensitivity of uMCP-1 and high specificity of uTWEAK displayed great specificity and sensitivity for proteinuria screening.Both uMCP-1 and uTWEAK were positively correlated with the impairments of LN, and the combined utility of untimed single uMCP-1 and uTWEAK might be used as potential predictors for proteinuria in LN.

Prevalence of Proteinuria and Other Abnormalities in Urinalysis Performed in the Urology Clinic

To compare the prevalence of proteinuria in the urology clinic with other outpatient settings. Chronic kidney disease is classified according to cause, glomerular filtration rate, and proteinuria. Proteinuria may be more prevalent in patients with known chronic kidney disease, renal disorders (benign or malignant), or after urologic surgery. A cross-sectional study of 3 populations undergoing urinalysis (UA) testing was carried out: general outpatients (n = 20,334), urology outpatients (n = 5023), and kidney cancer patients (n = 1016). Proteinuria was classified under Kidney Disease: Improving Global Outcomes guidelines: A1 (<30 mg), A2 (30-300 mg), and A3 (>300 mg). Proteinuria was detected throughout a community-based health system in 8.6% of UA (8.2%: A2; 0.4%: A3). In comparison, 18.6% of urology office-performed UA had proteinuria (16.0%: A2, 2.5%: A3) (P < .0001 vs non-urology). Kidney cancer patients were more likely to have proteinuria (17.9%: A2, 3.8%: A3). The proportion with A3 was significantly higher in urology and kidney cancer patients when compared with other outpatients (each P < .0001), and in the kidney cancer subgroup compared with all urology patients (P < .0001). Additional abnormalities were frequently present on microscopic analysis of UA in the urology clinic, including hematuria (20.9%), pyuria (21.8%), and bacteriuria (3.1%). The value of UA in the urology clinic as a screening test for proteinuria and other conditions appears high, with >56% having at least 1 abnormality. The population risk of proteinuria in the urology clinic is 18.5%, which is higher than that observed in non-urology clinics. Patients with kidney cancer appear more likely to have proteinuria than the average urology patient. We recommend evaluation of urology patients with UA to identify proteinuria.

Utility of Urinary Protein-Creatinine Ratio and Protein Content in a 24-Hour Urine Collection in Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis.

To systematically review literature on the utility of spot urinary protein-creatinine ratio (PCR) as a screening test for proteinuria and its ability to accurately measure proteinuria compared with 24-hour urine collection (24H-P) in patients with systemic lupus erythematosus (SLE). We conducted a literature search (1900-2015) for articles comparing PCR and 24H-P in SLE patients in the databases Medline, Web of Science, and Embase. Included studies and their results were critically appraised and analyzed. Thirteen studies (1,001 patients; 84.01% women) were included. Ten studies reported on Pearson's correlation (range 0.67-0.94), and 3 studies reported on Spearman's correlation (range 0.78-1.00). The meta-analysis of studies with Pearson's correlation showed a high overall correlation of 0.80 between 24H-P and PCR, yet with high heterogeneity (I(2) = 97.2%). Correlation analysis is not sufficient to evaluate the utility of a new test against the gold standard test, and analysis on agreement is required. Seven studies reported on agreement: 3 studies analyzed concordance correlation coefficient (0.48-0.94), 3 analyzed intraclass correlation coefficient (0.66-0.95), and 1 analyzed kappa coefficient (0.58). These results confirmed that the agreement between 24H-P and PCR was inappropriate. Three studies included Bland-Altman plots, and the results also demonstrated poor agreement between both tests. The PCR has a utility as a screening test for proteinuria in SLE patients. The studies' results of 24H-P and PCR showed poor agreement between both tests, signifying that PCR should not be a substitute for the gold standard test (24H-P) to accurately measure proteinuria.

Utility of untimed single urine protein/creatinine ratio as a substitute for 24-h proteinuria for assessment of proteinuria in systemic lupus erythematosus.

IntroductionIn this study, we determined: (1) the utility of an untimed sample of urine protein/creatinine ratio (PCR) as a screening test for proteinuria, (2) its ability to accurately measure proteinuria, and (3) cutoff values for PCR predicting protein content in a 24-h urine collection sample (24hP) of 0.5, 1.0, and 2.0 g/day.MethodsAnalysis was performed on data from a single lupus cohort (2008–2014). Proteinuria was measured in a 24hP and with PCR. On the basis of 24hP, samples were divided into 4 groups: group 1, <0.5 g/day; group 2, 0.5–0.99 g/day; group 3, 1–1.99 g/day; and group 4, ≥2 g/day. To determine the validity of PCR in screening for proteinuria, the Pearson correlation coefficient was determined for the urine samples with normal PCR (<0.05 g/mmol) and normal 24hP (<0.5 g/day). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of PCR were calculated. To determine the ability of PCR to accurately measure the level of proteinuria, in addition to the correlation between 24hP and PCR, agreement was determined by intraclass correlation coefficient, concordance correlation coefficient, and Bland-Altman plot between 24hP/24hC and PCR. The best cutoffs for PCR predicting a 24hP of 0.5, 1.0, and 2.0 g/day were determined with the receiver operating characteristic curve.ResultsThe correlation of the samples with normal PCR as well as 24hP (n = 552) was 0.29 (p < 0.0001). PCR sensitivity and specificity against 24hP were 91 % and 83 %, respectively. The PPV was 82.5 %, and the NPV was 91.4 %. The correlation for all samples (n = 1233) was high, but low to moderate for groups 1, 2, 3, and 4. The agreement for all samples was appropriate but poor for groups 1, 2, 3, and 4. PCR cutoffs for 24hP of 0.5, 1.0, and 2.0 g/day were 0.08, 0.16, and 0.35 g/mmol, respectively.ConclusionsPCR can be used as a screening test for proteinuria, and the best cutoff value to predict a 24hP of 0.5 g/day is 0.08 g/mmol (800 mg/g). The accurate level of proteinuria should be measured by the gold standard test, 24hP.

Albumin to creatinine ratio in a random urine sample: Correlation with severity of preeclampsia

BackgroundAlbumin to creatinine ratio (ACR) in random urine samples correlates well with 24-h protein excretion in potential glomerulopathy as in diabetic renal microangiopathy. Using this ratio as an appropriate screening test for proteinuria or for the disease severity in hypertensive disorders with pregnancy needs still to be verified. ObjectiveTo investigate the role of albumin to creatinine ratio in a random urine sample for assessment of severity of preeclampsia. Patients & methodsTwo separate groups, fifty women each, were enrolled. All were pregnant at their third trimester with confirmed preeclampsia. Based on their blood pressure levels, Group A, included patients with mild form of preeclampsia, whereas group B included cases with severe form. Albumin to creatinine ratio in random urine samples and the 24-h protein content in urine were assessed. ResultsACR and the 24-h urine protein excretion were significantly correlated, (r=0.583, p<0.001). Cut-off value for ACR for this group of patients was calculated to be 14.65mg/mmol, above which severity of the disease is highly probable. The sensitivity and specificity were 100% and 58.0%, respectively. The positive predictive value was 70.4% and negative predictive value was 100%. ConclusionsRandom urine ACR may be a reliable method for prediction and assessment of severity of preeclampsia. Using the estimated cut-off may add to the predictive value of such a simple quick test.

A study of the relationship between albuminuria, proteinuria and urinary reagent strips

The aims of this study were to examine the relationship between proteinuria and albuminuria and to assess the equivalence between the albumin to creatinine ratio (ACR) and the protein to creatinine ratio (PCR) at the cut-offs recommended by the National Institute for Health and Clinical Excellence (NICE) guidance on chronic kidney disease. The sensitivity and specificity of the reagent strips used in our laboratory for the detection of clinical proteinuria was also assessed. Urine samples (n = 117) were screened for protein using the Bayer Multistix 10SG and read manually. Urinary total protein and creatinine was measured on the Roche P Modular by the benzethonium chloride and kinetic Jaffe methods, respectively. Urinary albumin was measured by immunoturbidimetry on the Roche Cobas Mira. The relationship between urinary protein and albumin loss was non-linear (P < 0.05). As urinary protein loss increased the percentage of albumin to total protein increased. At the NICE guidance recommended cut-offs for clinical proteinuria (ACR > or =30 mg/mmol and PCR > or =50 mg/mmol) there was one discordant result between ACR and PCR (ACR <30 mg/mmol and PCR >50 mg/mmol). The Bayer Multistix 10SG had a sensitivity and specificity of 97% and 62%, respectively, for the detection of clinical proteinuria compared with ACR. The proportion of urinary total protein attributable to albumin changes with concentration. There was only one discordant result between ACR and PCR: therefore either ratio may be used for the identification of clinical proteinuria. As a screening test for proteinuria, the Bayer Multistix 10SG had an acceptable sensitivity but poor specificity.

Protein:Creatinine Ratio in Random Urine Samples Is a Reliable Marker of Increased 24-Hour Protein Excretion in Hospitalized Women with Hypertensive Disorders of Pregnancy

The protein:creatinine ratio in random, untimed urine samples correlates with 24-h protein excretion in pregnant women with and without hypertension. Nevertheless, whether this ratio is appropriate as a screening test for proteinuria is still unclear, in part because of the paucity of large studies. We measured protein:creatinine ratios in random urine samples and protein contents of 24-h urine samples in a cross-sectional study of 927 hospitalized pregnant women at >/=20-weeks of gestational age and in a 2nd cohort of 161 pregnant women. In the 2nd group, urine specimens were obtained before and after completion of the 24-h collections, avoiding 1st-morning void specimens. Protein excretion was >/=300 mg/24 h in 282 patients (30.4%). The urine protein:creatinine ratio and the 24-h protein excretion were significantly correlated (r = 0.98, P <0.001). The protein:creatinine ratio as an indicator of protein excretion >/=300 mg/24 h was >/=0.3. The sensitivity and specificity were 98.2% and 98.8%, respectively. Positive and negative predictive values were 97.2% and 99.2%, respectively, and positive and negative likelihood ratios were 79.2 and 0.02, respectively. The diagnostic accuracy of the urinary protein:creatinine ratio was corroborated in the 2nd cohort of patients, which also showed no statistically significant difference in protein:creatinine ratio between samples obtained >24 h apart. Random urinary protein:creatinine ratio is a reliable indicator of significant proteinuria (>300 mg/day) in nonambulatory pregnant women, irrespective of sampling time during the daytime. The protein:creatinine ratio may be reasonably used as an alternative to the 24-h urine collection method.

The Accuracy of Urine Dipsticks as a Screening Test for Proteinuria in Hypertensive Disorders of Pregnancy

Background. Proteinuria is used as a criterion in the classification system for hypertensive disorders of pregnancy including preeclampsia. The aim of the study was to evaluate the accuracy of dipstick urinalysis in a single voided urine sample and in an aliquot of a 24-hour urine collection in the assessment of proteinuria in hypertensive pregnant women, using the 24-hour urine protein excretion as the gold standard. Methods. One hundred ninety-eight women who presented with hypertension in pregnancy were recruited at the antenatal clinic at King Edward VIII Hospital in Durban, South Africa, a tertiary referral center. Exclusion criteria included women with eclampsia, urinary tract infection, and chronic renal disease. Routine dipstick urinalysis (Bayer) was performed by midwives for proteinuria, and a 24-hour urine specimen was collected for quantitative protein assessment. A laboratory technician performed urine dipstick test for protein on a mixed aliquot of the 24-hour urine specimen. This result, together with that of the screening dipstick urinalysis, was compared to the 24-hour urine protein excretion. Results. The results of the 198 patients were analyzed, of the total, 72 had preeclampsia. Using a value of ≥ 0.3 g protein excretion per 24 hours (1 + to 4 + on urine dipsticks) as positive, sensitivity, specificity, and predictive values for dipstick urinalysis were calculated. The positive predictive value for dipstick urinalysis ranged from 64.9% (single voided urine sample) to 94.2% (24-hour urine aliquot). The negative predictive value ranged from 75.2% (single voided urine sample) to 84.2% (24-hour urine aliquot). Conclusion. Dipstick urinalysis is not very accurate: therefore, all women presenting with hypertension during pregnancy should have a 24-hour urine protein measurement.

Association between albuminuria and proteinuria in the general population: the AusDiab Study.

The relationship between urinary albumin and total protein excretion and the appropriateness of one test over the other are unclear due to the paucity of large epidemiological studies of albuminuria and proteinuria. In screening for renal and cardiovascular disease, whether to measure albuminuria, proteinuria or both, is currently an unanswered question. Random urine samples from 10,596 (94.2%) participants of the Australian Diabetes, Obesity and Lifestyle Study were tested for albuminuria (urine albumin:creatinine > or =30 mg/g) and proteinuria (urine protein:creatinine > or =0.20 mg/mg). This study was a representative sample of the national non-institutionalized population drawn from 42 randomly selected urban and non-urban areas (census collector districts) across Australia. Among a representative cross-section of the Australian adult population, urine albumin excretion was strongly correlated with total protein excretion, particularly among the elderly, and those with diabetes mellitus, hypertension, obesity and renal impairment (P <0.001). Albuminuria performed well as a screening test for proteinuria: sensitivity 91.7% [95% confidence interval (CI) 87.7-94.5%], specificity 95.3% (95% CI 94.9-95.7%) and negative predictive value 99.8% (95% CI 99.7-99.9%). However, among those with proteinuria, 8% excreted albumin within the normal range. While albuminuria may be a suitable test for general population screening for renal and cardiovascular disease, it should not replace testing for proteinuria in those with known or suspected renal disease.

Structure of chronic inflammatory kidney diseases in workers of oil refineries

We determined the prevalence of chronic inflammatory kidney diseases by a continuous staged examination of 8264 workers and employees of oil refineries: 4051 (49.0%) women and 4213 (51.0%) men aged 20-60 years. At the first stage we conducted a mass cumulative examination of the workers using a screening test for proteinuria, blood pressure measurement, and a questionnaire. At the second stage, persons with suspected kidney disease were examined in an outpatient clinic - Nechiporenko urinalysis was performed, the degree of bacteriuria was determined, and an examination with the history was made. Patients were consulted by specialists (gynecologist, urologist, otorhinolaryngologist, dentist, oculist). The third stage was an in-depth examination of the identified patients in a specialized municipal nephrological department in order to establish the diagnosis of nephropathy. The latter included a detailed interview with occupational history, detailed clinical examination, isotopic renography, and, if indicated, excretory urography.