Comparison between urine albumin-to-creatinine ratio and urine protein dipstick testing for prevalence and ability to predict the risk for chronic kidney disease in the general population (Iwate-KENCO study): a prospective community-based cohort study

Adding creatinine to routine pregnancy tests: a decision tree for calculating the cost of identifying patients with CKD in pregnancy

BACKGROUND

Even in its early stages, chronic kidney disease (CKD) is associated with adverse pregnancy outcomes. The current guidelines for pregnancy management suggest identifying risk factors for adverse outcomes but do not mention kidney diseases. Since CKD is often asymptomatic, pregnancy offers a valuable opportunity for diagnosis. The present analysis attempts to quantify the cost of adding serum creatinine to prenatal screening and monitoring tests.

METHODS

The decision tree we built takes several screening scenarios (before, during and after pregnancy) into consideration, following the hypothesis that while 1:750 pregnant women are affected by stage 4-5 CKD and 1:375 by stage 3B, only 50% of CKD cases are known. Prevalence of abortions/miscarriages was calculated at 30%; compliance with tests was hypothesized at 50% pre- and post-pregnancy and 90% during pregnancy (30% for miscarriages); the cost of serum creatinine (production cost) was set at 0.20 euros. A downloadable calculator, which makes it possible to adapt these figures to other settings, is available.

RESULTS

The cost per detected CKD case ranged from 111 euros (one test during pregnancy, diagnostic yield 64.8%) to 281.90 euros (one test per trimester, plus one post-pregnancy or miscarriage, diagnostic yield 87.7%). The best policy is identified as one test pre-, one during and one post-pregnancy (191.80 euros, diagnostic yield 89.4%).

CONCLUSIONS

This study suggests the feasibility of early CKD diagnosis in pregnancy by adding serum creatinine to routinely performed prenatal tests and offers cost estimates for further discussion.

Diagnostic accuracy of a urine dipstick for detecting albuminuria in hypertensive patients

Background: Screening for albuminuria is generally recommended among patients with hypertension. While the urine dipstick is commonly used for screening urine albumin, there is little evidence about its diagnostic accuracy among these patients in Thailand. This study aimed to assess the diagnostic accuracy of a dipstick in Thai hypertensive patients for detecting albuminuria. Methods: This study collected the data of 3,067 hypertensive patients, with the results of urine dipstick and urine albumin-to-creatinine ratio (ACR) from random single spot urine being examined in the same day at least once, at Lampang Hospital, Thailand, during 2018. For ACR, a reference standard of ≥ 30 mg/g was applied to indicate the presence of albuminuria. Results: The sensitivity, specificity, positive predictive value (PPV), and negative predictive value of the trace result from dipsticks were 53.6%, 94.5%, 86.5%, and 75.5%, respectively. The area under the receiver operating characteristic curve of the dipstick was 0.748. Conclusion: Using the dipstick for screening albuminuria among hypertensive patients should not be recommended for mass screening due to its low sensitivity. In response to high PPV, a trace threshold of the dipstick may be used to indicate presence of albuminuria.

Comparison of dipstick and quantitative tests for proteinuria and hematuria in middle-aged, male Japanese employees: A single-center study

BACKGROUND AND AIMS

The early and reliable detection of chronic kidney disease is important. In the present study, we aimed to compare the diagnostic results for proteinuria and hematuria between the dipstick test used in primary occupational health examinations and the quantitative tests used in more thorough examinations in clinics.

METHODS

We conducted a single-center observational study of male staff (N = 573) at Kagoshima University who underwent a health examination in 2017. Both dipsticks and biochemical methods were used to assess proteinuria and hematuria.

RESULTS

For the dipstick test, the sensitivity, specificity, and positive predictive value were 55.6%, 92.4% and 10.4% for proteinuria, and 64.3%, 98.3% and 66.7% for hematuria, respectively. Four participants for whom false-negative results were obtained using dipsticks for proteinuria, and two of these had 3+ urinary glucose.

CONCLUSION

Qualitative tests for proteinuria and hematuria had low sensitivities and positive predictive values. Therefore, for the early and reliable detection of chronic kidney disease, the use of quantitative urine tests should be considered during occupational health examinations.

Urine High-Sensitivity Troponin I Predict Incident Cardiovascular Events in Patients with Diabetes Mellitus

In patients with diabetes mellitus (DM), incident cardiovascular (CV) events are associated with poor long-term outcomes. Serum high-sensitivity troponin I (hs-TnI) is widely used to diagnose and predict outcomes in patients with acute coronary syndrome, however, few studies have investigated the accuracy of urine hs-TnI as a predictor for incident CV events in patients with DM. The enrolled participants included patients with DM. Fresh urine hs-TnI levels were measured. Medical records of enrolled patients were used to determine the number of incident CV events prospectively for 3 months. The study cohort comprised 378 participants. We observed significantly higher levels of urine hs-TnI in those with than without subsequent incident CV events. The multivariate logistic regression analysis using different models consistently showed that urine hs-TnI > 4.10 pg/mL was an independent factor predictive of incident CV events. The ROC-AUC analysis revealed that the optimal cutoff value for urine hs-TnI for predicting incident CV events was 1.55 pg/mL and the area was 0.611 (p = 0.027). A single measurement of urinary hs-TnI, collected easily and non-invasively, may be an acceptable biomarker for predicting subsequent incident CV events in patients with DM.

Urinary strips for protein assays: easy to do but difficult to interpret!

Urine samples can be readily obtained from patients in everyday clinical practice. Therefore, the availability of urine allows physicians to obtain relevant clinical information in a timely manner. Since the measurement of urinary protein levels is essential in diagnosing and treating a host of diseases, the potential detection of urinary proteins by urinary strips in an easy, quick, and cheap way is very attractive. However, to ensure optimal use of urinary strips, one needs to be aware of their characteristics and their limitations. In this review, we discuss the characteristics of the urinary strips available for testing urinary protein levels and for detecting urinary albumin. We then consider their analytical performances in their most widely used clinical applications (e.g., in pregnancy, chronic kidney disease, diabetes, and screening of the general population).

Evaluation of the Clinitek®, a point-of-care urinalysis system for the measurement of clinically significant urinary metabolites and detection of haematuria in Schistosoma haematobium infected children in southern Côte d'Ivoire

BACKGROUND

Urinary schistosomiasis, caused by Schistosoma haematobium, remains a significant public health problem worldwide, despite years of efforts to control it. Haematuria is one of the notable indirect indicators of S. haematobium infection and is commonly assessed along with other routine screens using a urinary dipstick test. A portable "field friendly" electronic analyser would offer an automated and thus more objective read-out compared to visual-read dipstick methods.

METHODS

Within the framework of a Phase 2 praziquantel dose finding study in preschool- and school-aged children infected with S. haematobium, in southern Côte d'Ivoire, we compared a visual-read of the urine dipstick strips (Multistix PRO, Siemens Healthcare Diagnostics) to an automated reader (CLINITEK Status+ analyser™ Siemens Healthcare Diagnostics). Urine samples were collected from 148 pre-school aged and 152 school-aged children for urinalysis. Values were compared using a linear weighted kappa statistic and Bland-Altman analysis.

RESULTS

A very good correlation between the two methods for nitrites and haematuria was observed (κ coefficient of 0.88 and 0.82, respectively), while a good correlation was observed for leukocytes (κ coefficient of 0.63) A moderate to fair correlation was calculated (κ coefficient ≤ 0.6) for all other parameters. When the results were stratified according to infection intensity, the agreements were stronger from the high infection intensity sample measurements, for most of the parameters.

CONCLUSION

Our results demonstrate the device's utility in detecting haematuria and nitrites but underline the need for further development of this tool in order to improve its performance in the field.

Urine albumin-to-creatinine ratio and asymptomatic intracranial atherosclerotic stenosis in hypertensive patients

Intracranial atherosclerotic stenosis (ICAS) contributes to nearly 50% of stroke in China, especially in patients with hypertension. Urine albumin-to-creatinine ratio (ACR) has been related to stroke and other atherosclerotic cardiovascular diseases. However, there is limited information about the association of ACR and early impairment of cerebral vessels. Hereby we assessed the association of ICAS with ACR, estimated glomerular filtration rate (eGFR), and dipstick proteinuria in a stroke-free hypertensive population. We included 889 hypertension patients aged ≥60 years without prior stroke. Computed tomography angiography was performed to detect ICAS. ACR and dipstick proteinuria were tested from a random spot urine. eGFR was calculated using the CKD-EPI equation. Logistic regression was carried out to analyze the association of renal function with the presence, extent, and lesion number of ICAS. Elevated ACR (≥30 mg/g) was associated with ICAS after adjustment of confounding factors (odds ratio (OR) = 1.66, 95% confidence interval (CI): 1.21-2.29). Patients with elevated ACR were more prone to develop moderate-to-severe stenosis (OR = 1.57, 95% CI: 1.16-2.14) and more lesions (OR = 1.58, 95% CI: 1.16-2.15). Such association was independent of previously identified cardiovascular risk factors. No significant association was detected between ICAS and dipstick proteinuria or eGFR after adjustment. Our findings suggested that elevated ACR was associated with asymptomatic ICAS in an aged stroke-free hypertensive population.