BACKGROUND: Although the present diagnosis of acute kidney injury (AKI) involves measurement of acute increases in serum creatinine (SC) and reduced urine output (UO), measurement of UO is underutilized for diagnosis of AKI in clinical practice. The purpose of this investigation was to conduct a systematic literature review of published studies that evaluate both UO and SC in the detection of AKI to better understand incidence, healthcare resource use, and mortality in relation to these diagnostic measures and how these outcomes may vary by population subtype.
METHODS: The systematic literature review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Data were extracted from comparative studies focused on the diagnostic accuracy of UO and SC, relevant clinical outcomes, and resource usage. Quality and validity were assessed using the National Institute for Health and Care Excellence (NICE) single technology appraisal quality checklist for randomized controlled trials and the Newcastle-Ottawa Quality Assessment Scale for observational studies.
RESULTS: A total of 1729 publications were screened, with 50 studies eligible for inclusion. A majority of studies (76%) used the Kidney Disease: Improving Global Outcomes (KDIGO) criteria to classify AKI and focused on the comparison of UO alone versus SC alone, while few studies analyzed a diagnosis of AKI based on the presence of both UO and SC, or the presence of at least one of UO or SC indicators. Of the included studies, 33% analyzed patients treated for cardiovascular diseases and 30% analyzed patients treated in a general intensive care unit. The use of UO criteria was more often associated with increased incidence of AKI (36%), than was the application of SC criteria (21%), which was consistent across the subgroup analyses performed. Furthermore, the use of UO criteria was associated with an earlier diagnosis of AKI (2.4-46.0 h). Both diagnostic modalities accurately predicted risk of AKI-related mortality.
CONCLUSIONS: Evidence suggests that the inclusion of UO criteria provides substantial diagnostic and prognostic value to the detection of AKI.

BACKGROUND: Sarcopenia has been reported to play an important role in frailty syndrome. The serum creatinine/serum cystatin C ratio (Scr/Cys C ratio) has recently been recognized as a valuable indicator for assessing sarcopenia. However, few studies have examined the association between serum creatinine/serum cystatin C ratio and frailty. The objective of this study is to investigate the relationship between the serum creatinine/serum cystatin C ratio and frailty among older adults residing in the community.
METHODS: A Total of 1926 community-dwelling older adults aged ≥ 60 years in the 2011 waves of the China Health and Retirement Longitudinal Study (CHARLS) were included. The participants\' frailty status was determined using a 39 item frailty index (FI), which classified individuals as \"robust\" (FI ≤ 0.1), \"pre-frailty\" (0.1 < FI < 0.25), or \"frailty\" (FI ≥ 0.25). The Scr/Cys C ratio was determined by dividing the serum creatinine level (mg/dL) by the cystatin C level (mg/L). The one-way analysis of variance(ANOVA) and Chi-squared test (χ2)were applied to compare the differences between the 3 groups. Both linear regression and logistic regression models were used to further investigate the relationship between Scr/Cys C ratio and frailty.
RESULTS: After adjusting for potential confounding factors, the study revealed that participants in the Q1 quartile of Scr/Cys C ratio had increased odds of frailty (Q1vs.Q4: OR = 1.880, 95% CI 1.126-3.139, p = 0.016) compared with those in the Q4 quartile group. In fully adjusted logistic regression models, male participants in the Q2 quartile of Scr/Cys C ratio were significantly correlated with higher odds of pre-frailty (Q2 vs.Q4: OR = 1.693, 95%CI 1.040-2.758, p = 0.034). However, this correlation was not observed in females (OR = 0.984, 95% CI 0.589-1.642, p = 0.950,). Additionally, the study observed an increase in both the frailty index and the incidence of frailty as age increased in both males and females.
CONCLUSIONS: Among community-dwelling older adults, lower Serum creatinine to cystatin C ratio were found to be associated with increased odds of frailty prevalence in males.

UNASSIGNED: The NKF-ASN Task Force recommends accurate kidney function estimation avoiding biases through racial adjustments. We explored the use of multiple kidney function biomarkers and hence estimated glomerular filtration rate (eGFR) equations to improve kidney function calculations in an ethnically diverse patient population.
UNASSIGNED: Prospective community cohort study.
UNASSIGNED: rural New Mexico clinic with patients > 18 yo.
UNASSIGNED: Markers of kidney function, IDMS-Creatinine (SCr), chemiluminescence Beta-2 Microglobulin (B2M), Nephelometry-calibrated ELISA Cystatin C (CysC), inflammation, glucose tolerance, demographics, BUN/UACR from the baseline visit of the COMPASS cohort, were analyzed by Kernel-based Virtual Machine learning methods.
UNASSIGNED: Among 205 participants, the mean age was 50.1, 62% were female, 54.1% Hispanic American and 30.2% Native American. Average kidney function biomarkers were: SCr 0.9 mg/dl, B2M 1.8 mg/L, and CysC 0.7 mg/dl. The highest agreement was observed between SCr and B2M-based eGFR equations [mean difference in eGFRs: (4.48 ml/min/1.73m2], and the lowest agreement between B2M and CysC-based eGFR equations (-24.75 ml/min/1.73m2). There was no pattern of association between the differences in eGFR measures and gender. In the continuous analyses, the absolute eGFR value (p<2 x 10-16) and serum albumin (p =6.4 x 10-5) predicted the difference between B2M- and SCr-based e-GFR. The absolute eGFR value (p<2 x 10-16) and age (p =7.6 x 10-5) predicted the difference between CysC- and SCr-based e-GFR.
UNASSIGNED: Relatively small sample size, elevated inflammatory state in majority of study participants and no inulin excretion rate measurements.
UNASSIGNED: B2M should be strongly considered as a kidney function biomarker fulfilling the criteria for the NKF-ASN. B2M\'s eGFR equation does not need adjustment for gender or race and showed the highest agreement with SCr-based eGFR equations.

BACKGROUND: Pre-haemodialysis (HD) serum creatinine levels are reliable and inexpensive markers of muscle mass and important predictors of survival in patients with stable chronic HD. We aimed to assess whether changes in pre-HD serum creatinine levels during a 2-year period are linked to long-term patient survival.
METHODS: We retrospectively analysed patients enrolled in a periodic HD quality assessment program. Of the 21 846 participants in the fourth HD quality assessment program, 13 765 were presented in the fifth, of which 10 299 eligible patients were included in this study. We assessed the change in serum creatinine levels over 2 years. The patients were categorized into the following three groups: stable group (patients with change in serum creatinine < 1 mg/dL during 2 years of HD, n = 5664), increasing group (patients with increase in serum creatinine ≥ 1 mg/dL, n = 2419) and decreasing group (patients with decrease in serum creatinine ≥ 1 mg/dL, n = 2216).
RESULTS: The duration of HD at baseline was 62-83 months, with diabetic kidney disease being the most common cause of kidney failure in 36.4% of patients. The 5-year patient survival rates in the stable, increasing and decreasing groups were 69.1%, 71.3% and 66.8%, respectively. The decreasing group had poorer patient survival than the other two groups (P = 0.083 for stable vs. increasing group; P = 0.011 for stable vs. decreasing group; P < 0.001 for increasing vs. decreasing group). There was no significant difference in the cardiovascular event-free survival rate among the three groups. Multivariable Cox regression analyses revealed the highest hazard ratio (HR) for mortality in the decreasing group (HR 1.33, 95% confidence interval [CI] 1.21-1.45, P < 0.001 vs. stable group; HR 1.50, 95% CI 1.34-1.69, P < 0.001 vs. increasing group). The increasing group exhibited a lower risk of mortality than the stable group (HR 0.88, 95% CI 0.81-0.97, P = 0.008). Subgroup analyses based on age, HD vintage, sex, Charlson comorbidity index score, presence of diabetes and baseline serum creatinine level tertiles revealed that the decreasing group exhibited the highest mortality among all subgroups.
CONCLUSIONS: Our results demonstrate that changes in pre-HD serum creatinine levels over 2 years of HD were associated with all-cause mortality in patients undergoing HD. This finding suggests a simple and promising approach for clinicians in the prognosis and management of patients undergoing HD.

暂无摘要。

UNASSIGNED: Due to its potential nephrotoxicity, screening for pre-existing renal function disorders has become a routine clinical assessment for initiating Tenofovir diphosphate fumarate (TDF)-containing antiretroviral treatment (ART) or pre-exposure prophylaxis (PrEP) in pregnant and non-pregnant adults. We aimed to establish reference values for commonly used markers of renal function in healthy pregnant women of African origin.
UNASSIGNED: Pregnant women ≥18 years, not living with HIV, and at 14-28 weeks gestation were enrolled in a PrEP clinical trial in Durban, South Africa between September 2017 and December 2019. Women were monitored 4-weekly during pregnancy until six months postpartum. We measured maternal weight and serum creatinine (sCr) at each visit and calculated creatinine clearance (CrCl) rates using the Cockcroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) formulae. Reference ranges for sCr and CrCl by CG and MDRD calculations were derived from the mean ± 2SD of values for pregnancy and postdelivery.
UNASSIGNED: Between 14--and 40 weeks gestation, 249 African women not exposed to TDF-PrEP contributed a total of 1193 renal function values. Postdelivery, 207 of these women contributed to 800 renal function values. The normal reference range for sCr was 30-57 and 32-60 umol/l in the 2nd and 3rd trimesters of pregnancy. Normal reference ranges for CrCl using the MDRD calculation were 129-282 and 119-267 ml/min/1.73m2 for the 2nd and 3rd trimesters, respectively. Using the CG method of calculation, normal reference ranges for CrCl were 120-304 and 123-309 ml/min/1.73m2 for the 2nd and 3rd trimesters respectively. In comparison, the normal reference range for sCr, CrCl by MDRD and CG calculations postpartum was 40-77 umol/l, 92-201, and 90-238 ml/min/1.73m2, respectively.
UNASSIGNED: In African women, the Upper Limit of Normal (ULN) for sCr in pregnancy is approximately 20% lower than 6 months postnatally. Inversely, the Lower Limit of Normal (LLN) for CrCl using either MDRD or CG equation is approximately 35% higher than 6 months postnatally. We provide normal reference ranges for sCr and CrCl for both methods of calculation and appropriate for the 2nd and 3rd trimesters of pregnancy in African women.
Screening for pre-existing renal function disorders has become a routine clinical assessment for initiating TDF-containing antiretroviral treatment or pre-exposure prophylaxis in adults including pregnant women. Pregnancy inherently increases renal function, hence normal reference standards for non-pregnant adults cannot be used for pregnant women. In a secondary analysis of data from a healthy pregnant population not living with HIV who participated in a PrEP clinical trial, we established reference intervals for serum creatinine (sCr) concentration and creatinine clearance (CrCl) during pregnancy and postpartum in an African population. Using sCr and CrCl values for 249 healthy pregnant African women, we can confirm that the upper limit of normal for sCr in pregnancy is 20% lower than that for the 6-month postnatal period and recommend an upper limit of 57 umol/l and 60 umol/l in the second and third trimesters respectively to determine normal renal function in pregnant African women.We further determined the lower limit of normal for creatinine clearance using two methods of calculation, which was 35% higher than that of the postnatal period. Using the modification of diet in renal disease calculation, we recommend a lower limit of 129 and 119 ml/min/1.73m2 for the second and third trimesters respectively. Using the Cockcroft–Gault calculation, we recommend a lower limit of 120 and 123 ml/min/1.73m2 for the second and third trimesters respectively. Using current standard cut-off values estimated for adults may lead to underreporting of abnormal renal function in African pregnant women.

UNASSIGNED: Chronic liver disease is a common and important clinical problem.Hepatorenal syndrome (HRS) is a life threatening complication. Serum creatinine (Cr) remains the only conventional indicator of renal function. However, the interpretation of serum Cr level can be confounded by malnutrition and reduced muscle mass often observed in patients with severe liver disease. Here, we present a cross-sectional study to explore the sensitivity and specificity of other markers as urinary KIM-1 and NGAL for cases of HRS.
UNASSIGNED: Cross-sectional study was conducted on 88 patients who were admitted to Alexandria main university hospital. Enrolled patients were divided in two groups; group 1: patients with advanced liver cirrhosis (child B and C) who have normal kidney functions while group 2: patients who developed HRS. Stata© version 14.2 software package was used for analysis.
UNASSIGNED: Group 1 included 18 males and 26 females compared to 25 males and 19 females in group 2 (p = 0.135). Only the urinary KIM-1 showed a statistically significant difference between both groups in the multivariate logistic regression analysis adjusted for gender, serum bilirubin, serum albumin, INR, serum K, AST and ALT levels.
UNASSIGNED: In conclusion, our study aligns with prior research, as seen in the consistent findings regarding Urinary NGAL elevation in cirrhotic patients with AKI. Urinary KIM-1, independent of Urinary NGAL, may have a role in precisely distinguishing between advanced liver cirrhosis and HRS and merits further exploration.

Serum creatinine in neonates follows complex dynamics due to maturation processes, most pronounced in the first few weeks of life. The development of a mechanism-based model describing complex dynamics requires high expertise in pharmacometric (PMX) modeling and substantial model development time. A recently published machine learning (ML) approach of low-dimensional neural ordinary differential equations (NODEs) is capable of modeling such data from newborns automatically. However, this efficient data-driven approach in itself does not result in a clinically interpretable model. In this work, an approach to deriving an interpretable model with reasonable PMX-type functions is presented. This \"translation\" was applied to derive a PMX model for serum creatinine in neonates considering maturation processes and covariates. The developed model was compared to a previously published mechanism-based PMX model whereas both models had similar mechanistic structures. The developed model was then utilized to simulate serum creatinine concentrations in the first few weeks of life considering different covariate values for gestational age and birth weight. The reference serum creatinine values derived from these simulations are consistent with observed serum creatinine values and previously published reference values. Thus, the presented NODE-based ML approach to model complex serum creatinine dynamics in newborns and derive interpretable, mathematical-statistical components similar to those in a conventional PMX model demonstrates a novel, viable approach to facilitate the modeling of complex dynamics in clinical settings and pediatric drug development.

UNASSIGNED: The objective of this study was to explore the association between the ratio of serum creatinine to cystatin C to waist circumference (CCR/WC) and hypertension.
UNASSIGNED: The study utilized data extracted from the China Health and Retirement Longitudinal Study. In the cross-sectional analysis, logistic regression analyses were employed to examine the association between the CCR/WC ratio and hypertension. By utilizing restricted cubic splines, potential non-linear associations between the CCR/WC ratio and hypertension were explored. In the longitudinal analysis, the association between CCR/WC quartiles (Q1-Q4) and the risk of new-onset hypertension was evaluated by Cox proportional-hazards models.
UNASSIGNED: In total, 7,253 participants were enrolled. The study unveiled an inverse association with hypertension, demonstrating an odds ratio (OR) of 0.29 (95% confidence interval [CI]: 0.23-0.37, P < 0.001). Among males, an OR of 0.38 (95% CI: 0.25-0.58, P < 0.001) was observed, while among females, an OR of 0.41 (95% CI: 0.28-0.60, P < 0.001) was noted. There was an absence of a nonlinear association between the CCR/WC ratio and hypertension. Cox regression analysis unveiled a reduced risk of hypertension in Q3 (Hazard ratios [HR]: 0.69, 95% CI: 0.58-0.82, P < 0.001) and Q4: (HR: 0.70, 95% CI: 0.59-0.83, P < 0.001) in compared to the Q1 of the CCR/WC ratio, and sex-specific analysis yielded consistent results.
UNASSIGNED: This study emphasizes the potential association between an elevated CCR/WC ratio and a reduced risk of hypertension.

BACKGROUND: The number of elderly patients who require surgery as their primary treatment has increased rapidly in recent years. Among 300 million people globally who underwent surgery every year, patients aged 65 years and over accounted for more than 30% of cases. Despite medical advances, older patients remain at higher risk of postoperative complications. Early diagnosis and effective prediction are essential requirements for preventing serious postoperative complications. In this study, we aim to provide new biomarker combinations to predict the incidence of postoperative intensive care unit (ICU) admissions > 24 h in elderly patients.
METHODS: This investigation was conducted as a nested case-control study, incorporating 413 participants aged ≥ 65 years who underwent non-cardiac, non-urological elective surgeries. These individuals underwent a 30-day postoperative follow-up. Before surgery, peripheral venous blood was collected for analyzing serum creatinine (Scr), procalcitonin (PCT), C-reactive protein (CRP), and high-sensitivity CRP (hsCRP). The efficacy of these biomarkers in predicting postoperative complications was evaluated using receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) values.
RESULTS: Postoperatively, 10 patients (2.42%) required ICU admission. Regarding ICU admissions, the AUCs with 95% confidence intervals (CIs) for the biomarker combinations of Scr × PCT and Scr × CRP were 0.750 (0.655-0.845, P = 0.007) and 0.724 (0.567-0.882, P = 0.015), respectively. Furthermore, cardiovascular events were observed in 14 patients (3.39%). The AUC with a 95% CI for the combination of Scr × CRP in predicting cardiovascular events was 0.688 (0.560-0.817, P = 0.017).
CONCLUSIONS: The innovative combinations of biomarkers (Scr × PCT and Scr × CRP) demonstrated efficacy as predictors for postoperative ICU admissions in elderly patients. Additionally, the Scr × CRP also had a moderate predictive value for postoperative cardiovascular events.
BACKGROUND: China Clinical Trial Registry, ChiCTR1900026223.