Difficulties in assessing renal function in patients with cirrhosis: potential impact on patient treatment

Kidney disease in patients with chronic liver disease: Does sex matter?

Kidney disease in patients with liver disease is serious and increases mortality. Up to 50% of patients hospitalized experience an episode of acute kidney injury. In general, men with liver disease are thought to be at increased risk of kidney disease. However, this association should be considered with caution because most studies use creatinine-based inclusion criteria, which is negatively biased against women. In this review, we synthesize data on sex differences in kidney disease in patients with chronic liver disease in the clinical setting and discuss potential physiologic underpinnings.

MELD-GRAIL-Na Is a Better Predictor of Mortality Than MELD in Korean Patients with Cirrhosis

Background and Objectives: The Child–Pugh (CP) score and Model for End-Stage Liver Disease (MELD) are classical systems for predicting mortality in patients with liver cirrhosis (LC). The MELD-GFR assessment in liver disease–sodium (MELD-GRAIL-Na) was designed to better reflect renal function and, therefore, provide better mortality predictions. This study aimed to compare the prediction accuracy of MELD-GRAIL-Na compared to CP and MELD in predicting short-term (1- and 3-month) mortality in Korean patients. Materials and Methods: Medical records of patients with LC admitted to the Konkuk University Hospital from 2015 to 2020 were retrospectively reviewed. Predictive values of the CP, MELD, and MELD-GRAIL-Na for 1-month and 3-month mortality were calculated using the area under the receiver operating curve (AUROC) and were compared using DeLong’s test. Results: In total, 1249 patients were enrolled; 102 died within 1 month, and 146 within 3 months. AUROCs of CP, MELD, and MELD-GRAIL-Na were 0.831, 0.847, and 0.857 for 1-month mortality and 0.837, 0.827, and 0.835 for 3-month mortality, respectively, indicating no statistical significance. For patients with CP classes B and C, AUROCs of CP, MELD, and MELD-GRAIL-Na were 0.782, 0.809, and 0.825 for 1-month mortality and 0.775, 0.769, and 0.786 for 3-month mortality, respectively. There was a significant difference between CP and MELD-GRAIL-Na in predicting 1-month mortality (p = 0.0428) and between MELD and MELD-GRAIL-Na in predicting 1-month (p = 0.0493) and 3-month mortality (p = 0.0225). Conclusions: Compared to CP and MELD, MELD-GRAIL-Na was found to be a better and more useful system for evaluating short-term (1- and 3-month) mortality in Korean patients with cirrhosis, especially those with advanced cirrhosis (CP class B and C).

Plasma Cystatin C Level is a Prognostic Marker of Morbidity and Mortality in Hospitalized Decompensated Cirrhotic Patients

Introduction : Cystatin C (CysC) is biomarker for early detection of acute kidney injury (AKI). However, there is limited evidence in decompensated cirrhotic patients without AKI at admission. This study aimed to assess CysC as a predictor of 90-day mortality. Methods : Decompensated cirrhotic patients without AKI were prospectively enrolled. CysC and creatinine were measured within 24 hours of admission and compared between patients with in-hospital complications (AKI, hepatorenal syndrome (HRS), acute-on-chronic liver failure (ACLF)) vs. those without, and survivors vs. non-survivors. The AUROC and cut-off point of CysC in predicting 90-day mortality were determined. Results : Of 137 decompensated cirrhotic patients, 46 without AKI at admission were included (58.7% male, age 60.8 ± 11.2years, MELD 13.1 ± 5.1, ChildA / B / C 43.5% / 39.1% / 17.4%). The mean CysC level tended to be higher in patients with ACLF (1.52 ± 0.60 vs. 1.11 ± 0.28, p = 0.05), and significantly higher in non-survivors than survivors (1.61 ± 0.53 vs. 1.08 ± 0.28, p = 0.013). The 90-day mortality rate was 21.7%. After adjusting with age and bacterial infection on admission, CysC level  ≥ 1.25 mg / L was significantly associated with 90-day mortality. The CysC cut-off level  ≥ 1.25 mg / L provided 80% sensitivity and 75% specificity for predicting 90-day mortality. Conclusion : Plasma CysC within 24 hours could be used as a predictor for 90-day mortality and development of ACLF in decompensated cirrhotic patients. J. Med. Invest. 68 : 302-308, August, 2021.

Cystatin C and interleukin-6 for prognosticating patients with acute decompensation of cirrhosis

Background and Aim

Systemic inflammation and organ dysfunction/failure can complicate acute decompensation (AD) of cirrhosis with progression to acute‐on‐chronic liver failure (ACLF), leading to increased mortality. There are few studies on serum biomarkers predicting renal dysfunction (RD) or ACLF in AD. Serum cystatin C (CysC) and interleukin‐6 (IL‐6) were evaluated for predicting RD, ACLF, and mortality in AD patients.

Methods

Consecutive AD patients seen from January 2018 to June 2019 were included. IL‐6 and CysC were measured in serum at the time of index presentation. Patients were followed for 90 days or until primary (development of RD) or secondary outcomes (development of ACLF or mortality). Multivariate analysis was performed to find whether CysC and IL‐6 can independently predict primary and secondary outcomes.

Results

A total of 124 patients were screened; 88 patients were included. On follow up, 22 (27.3%) developed RD, 11 (11/57, 19.3%) developed ACLF, and 21 (24%) died. The CysC predicted RD (odds ratio [OR] 7.97, 95% confidence interval [CI] 2.70–23.53, P = 0.001) and ACLF (OR 5.486, 95% CI 1.456–20.6, P = 0.012) development. IL‐6 was not an independent predictor of RD (P = 0.315), ACLF (P = 0.168), and mortality (P = 0.225).

Conclusion

Serum CysC can predict the development of RD and ACLF in patients of cirrhosis with AD.

Acute and chronic kidney disease after pediatric liver transplantation: An underestimated problem

Acute and chronic kidney injuries represent critical issues after liver transplantation (LTx), but whereas renal dysfunction in adult transplant patients is well documented, little is known about its prevalence in childhood. It is a challenge to accurately evaluate renal function in patients with liver disease, due to several confounding factors. Creatinine-based equations estimating glomerular filtration rate, validated in nephropathic patients without hepatic issues, are frequently inaccurate in end-stage liver disease, underestimating the real impact of renal disease. Moreover, whereas renal issues observed within 1 year from LTx were often related to acute injuries, kidney damage observed after 5-7 years from LTx, is due to chronic, irreversible mechanisms. Most immunosuppression protocols are based on calcineurin inhibitors (CNIs) and corticosteroids, but mycophenolate mofetil or sirolimus could play significant roles, also in children. Early diagnosis and personalized treatment represent the bases of kidney disease management, in order to minimize its close relation with increased mortality. This review analyzed acute and chronic kidney damage after pediatric LTx, also discussing the impact of pre-existent renal disease. The main immunosuppressant strategies have been reviewed, highlighting their impact on kidney function. Different methods assessing renal function were reported, with the potential application of new renal biomarkers.

Free Cortisol Is a More Accurate Marker for Adrenal Function and Does Not Correlate with Renal Function in Cirrhosis

BACKGROUND

The accuracy of diagnosis and clinical implications of the hepatoadrenal syndrome, as currently diagnosed using total cortisol, remain to be validated.

AIM

The aim of this study was to assess adrenal function using free cortisol in stable cirrhosis and study the potential implications of any abnormalities for renal and/or cardiac function.

METHODS

Sixty-one stable consecutively enrolled patients with cirrhosis underwent assessment of adrenal function using the low-dose short Synacthen test, renal function by ⁵¹Cr-EDTA glomerular filtration rate (GFR), and cardiac function by two-dimensional echocardiography.

RESULTS

Eleven patients (18%) had total peak cortisol (PC) < 500 nmol/L, but no patient had free PC < 33 nmol/L indicating that diagnosis of AI using total cortisol is not confirmed using free cortisol. Free cortisol did not correlate with GFR or parameters of cardiac function. Patients with higher Child-Pugh class had progressively lower free cortisol. Patients with low GFR < 60 mL/min (N = 22) had more frequently grade II-III diastolic dysfunction (66.7% vs. 17.6%; p = 0.005) and had higher Child-Pugh and MELD score compared to those with normal GFR.

CONCLUSIONS

Diagnosis of AI using total cortisol is not confirmed using free cortisol and is thus considered unreliable in cirrhosis. Free cortisol is not associated with renal or cardiac dysfunction. Lower free cortisol in more advanced stages of liver disease might be secondary to decreased synthesis due to lower cholesterol levels. Irrespective of free cortisol, parameters of cardiac dysfunction are associated with renal impairment supporting the cardio-renal hypothesis.

Plasma cystatin C is a predictor of renal dysfunction, acute-on-chronic liver failure, and mortality in patients with acutely decompensated liver cirrhosis

The development of acute-on-chronic liver failure (ACLF) in patients with liver cirrhosis is associated with high mortality rates. Renal failure is the most significant organ dysfunction that occurs in ACLF. So far there are no biomarkers predicting ACLF. We investigated whether cystatin C (CysC) and neutrophil gelatinase-associated lipocalin (NGAL) can predict development of renal dysfunction (RD), hepatorenal syndrome (HRS), ACLF, and mortality. We determined the plasma levels of CysC and NGAL in 429 patients hospitalized for acute decompensation of cirrhosis in the EASL-CLIF Acute-on-Chronic Liver Failure in Cirrhosis (CANONIC) study. The patients were followed for 90 days. Patients without RD or ACLF at inclusion but with development of either had significantly higher baseline concentrations of CysC and NGAL compared to patients without. CysC, but not NGAL, was found to be predictive of RD (odds ratio, 9.4; 95% confidence interval [CI], 1.8-49.7), HRS (odds ratio, 4.2; 95% CI, 1.2-14.8), and ACLF (odds ratio, 5.9; 95% CI, 1.3-25.9). CysC at day 3 was not found to be a better predictor than baseline CysC. CysC and NGAL were both predictive of 90-day mortality, with hazard ratios for CysC of 3.1 (95% CI, 2.1-4.7) and for NGAL of 1.9 (95% CI, 1.5-2.4).

CONCLUSION

Baseline CysC is a biomarker of RD, HRS, and ACLF and an independent predictor of mortality in patients with acutely decompensated liver cirrhosis, though determining CysC at day 3 did not provide any benefit; while NGAL is also associated with short-term mortality, it fails to predict development of RD, HRS, and ACLF. Baseline CysC may help to identify patients at risk earlier and improve clinical management. (Hepatology 2017;66:1232-1241).

Perspective on Clinical Application of Biomarkers in AKI

Several biomarkers of renal injury have been identified but the utility of these biomarkers is largely confined to research studies, whereas widespread clinical applicability is limited. This is partly because the use of serum creatinine as the comparator has several limitations and restricts the full interpretation of biomarker performance. To highlight the potential for clinical application of biomarkers, the most pertinent biomarker data are summarized here, using clinically relevant scenarios in which biomarkers could assist with diagnostic and management dilemmas. The paradigms proposed in this review aim to enhance the clinical diagnosis, management, and prognosis of AKI through the combined use of available clinical markers and novel inflammatory, injury, and repair biomarkers.

Early trends in cystatin C and outcomes in patients with cirrhosis and acute kidney injury

Background. Acute kidney injury (AKI) is a common and severe complication in patients with cirrhosis. Progression of AKI to a higher stage associates with increased mortality. Intervening early in AKI when renal dysfunction is worsening may improve outcomes. However, serum creatinine correlates poorly with glomerular filtration in patients with cirrhosis and fluctuations may mask progression early in the course of AKI. Cystatin C, a low-molecular-weight cysteine proteinase inhibitor, is a potentially more accurate marker of glomerular filtration. Methods. We conducted a prospective multicenter study in patients with cirrhosis comparing changes in cystatin and creatinine immediately following onset of AKI as predictors of a composite endpoint of dialysis or mortality. Results. Of 106 patients, 37 (35%) met the endpoint. Cystatin demonstrated less variability between samples than creatinine. Patients were stratified into four groups reflecting changes in creatinine and cystatin: both unchanged or decreased 38 (36%) (Scr−/CysC−); only cystatin increased 25 (24%) (Scr−/CysC+); only creatinine increased 15 (14%) (Scr+/CysC−); and both increased 28 (26%) (Scr+/CysC+). With Scr−/CysC− as the reference, in both instances where cystatin rose, Scr−/CysC+ and Scr+/CysC+, the primary outcome was significantly more frequent in multivariate analysis, P = 0.02 and 0.03, respectively. However, when only creatinine rose, outcomes were similar to the reference group. Conclusions. Changes in cystatin levels early in AKI are more closely associated with eventual dialysis or mortality than creatinine and may allow more rapid identification of patients at risk for adverse outcomes.

Acute kidney injury in patients with cirrhosis: perils and promise

A 62-year-old man with cirrhosis secondary to hepatitis C and chronic alcohol abuse was admitted to the intensive care unit with hematemesis and mental status changes. Physical examination showed ascites and stigmata of chronic liver disease. Blood pressure was noted as 87/42 mm Hg and laboratory studies showed a serum creatinine level of 0.8 mg/dL, an estimated glomerular filtration rate of 84 mL/min/1.73 m(2) calculated using the Modification of Diet in Renal Disease Study equation, a serum sodium level of 123 mEq/L, a total serum bilirubin level of 4.3 mg/dL, and an international normalization ratio of 1.6. The patient was resuscitated with packed red blood cells and fresh-frozen plasma and bleeding was controlled. However, on the third day of admission, creatinine level increased to 1.5 mg/dL. Examination of urine sediment showed 1 to 5 bilirubin-stained granular casts per high-powered field and a few renal tubular epithelial cells. The urine sodium level was 21 mEq/L and the fractional excretion of sodium was 0.43%.

AKI in a patient with cirrhosis and ascites

Acute deterioration in kidney function in a patient with cirrhosis and ascites presents a difficult management problem, and it is associated with increased mortality. In this Attending Rounds paper, a patient with oliguric AKI is presented to emphasize the role of laboratory and bedside tests that can establish a correct diagnosis and lead to appropriate management.

Management of critically-ill cirrhotic patients

Cirrhotic patients are prone to develop life-threatening complications that require emergency care and ICU admission. They can present specific decompensations related to cirrhosis such as variceal bleeding and hepatorenal syndrome (HRS) or other critical events also observed in the general population such as severe sepsis or septic shock. Clinical management of all these entities requires a specific approach in cirrhosis. Cirrhotic patients have a hyperdynamic circulation with high cardiac output and low systemic vascular resistance in the absence of infection. Circulatory dysfunction increases the susceptibility of critically-ill cirrhotic patients to develop multiple organ failure and attenuates vascular reactivity to vasopressor drugs. HRS, a severe functional renal failure occurring in patients with advanced cirrhosis and ascites, is also secondary to this circulatory dysfunction that leads to an extreme renal vasoconstriction. Moreover, hypotensive cirrhotic patients require a carefully balanced replacement of volemia, since overtransfusion increases portal hypertension and the risk of variceal bleeding and undertransfusion causes tissue hypoperfusion which increases the risk of multiple organ failure. Cirrhotic patients are also at a high risk for development of other bleeding complications and are more susceptible to nosocomial infections. This extreme complexity of critically-ill cirrhotic patients requires a specific medical approach that should be known by general intensivists since it has a negative impact on patient prognosis. This review will focus on the diagnostic approach and treatment strategies currently recommended in the critical care management of patients with cirrhosis.

Limitations of compensated Jaffe creatinine assays in cirrhotic patients

OBJECTIVES

This study aimed to evaluate the impact of two creatinine measurement methods on the Model for End Stage Liver Disease (MELD) score and glomerular filtration rate estimation (eGFR) in cirrhotic patients. We focused on ID-MS traceable method such as compensated Jaffe (cJafCreat) and enzymatic (EnzCreat) methods.

DESIGN AND METHODS

Potential protein-related interferences in creatinine determination were evaluated using dialysates spiked with albumin. MELD score, CKD-EPI formula creatinine-based eGFR and cystatin C-based eGFR were evaluated in 100 cirrhotic patients.

RESULTS

In vitro model demonstrated that low protein levels result in an underestimation of creatinine levels using cJafCreat. In patients, cJafCreat created a negative bias of -6.1 μmol/L that led to higher eGFR and lower MELD scores.

CONCLUSIONS

cJafCreat contributes to an overestimation of renal function in cirrhotic patients and may alter cirrhosis-severity assessment. Compensated Jaffe assays should therefore be replaced by enzymatic methods.

Pitfalls in assessing renal function in patients with cirrhosis--potential inequity for access to treatment of hepatorenal failure and liver transplantation

Serum creatinine is universally used to assess renal function in clinical practice. Creatinine and changes in serum creatinine are used to define acute kidney injury and hepatorenal syndrome (HRS) in patients with progressive liver disease. In addition, creatinine is a key variable in the calculation used to determine priority for liver transplantation in many countries. As there is no universal standardized creatinine assay, there is variation in creatinine determinations between laboratory assays, compounded by assay interference due to chromogens, including bilirubin. This leads to patients with the same actual renal function potentially being offered different treatment options, in terms of access to therapy for HRS and priority waiting time for liver transplantation. Alternative methods for assessing renal function either also tend to overestimate renal function or are too time consuming and expensive to provide practical alternatives for standard clinical practice. Standardization of creatinine assays with readily available reference standards would help minimize interlaboratory variation; of the current creatinine assays, enzymatic creatinine appears more accurate, but even this is inaccurate at high bilirubin concentrations. Further work is required to determine whether interpatient variation can be reduced by correcting creatinine and cystatin measurements for muscle mass.