Kidney Injury in Liver Disease

The progression of hepatorenal syndrome-acute kidney injury in acute alcohol-associated hepatitis: renal outcomes after liver transplant

Background

Hepatorenal syndrome-acute kidney injury (HRS-AKI) is a complication of advanced liver disease in patients with ascites and circulatory dysfunction. Little data remain on the relationship between HRS-AKI outcomes and different etiologies of liver disease post-liver transplant (LT).

Objectives

The primary aim was to evaluate the effect of HRS-AKI on renal outcomes in patients with acute alcohol-associated hepatitis (AAH) compared to chronic liver disease (CLD) after LT. The secondary aim was to evaluate the impact of acuity and chronicity of alcohol-associated liver disease in patients with HRS-AKI post-LT renal outcomes.

Design

A retrospective observational study of patients undergoing urgent inpatient liver transplant evaluation (LTE) for cirrhosis and AAH at single academic LT center between October 2017 and July 2021 was conducted.

Methods

Patients with HRS-AKI were selected based on indication for LTE: acute AAHHRS or CLDHRS. CLDHRS was categorized by disease etiology: cirrhosis due to alcohol (A-CLDHRS) versus cirrhosis from other causes (O-CLDHRS). CLD patients without HRS-AKI were labeled CLDno HRS.

Results

A total of 210 subjects underwent LTE; 25% were evaluated for AAH and 75% were evaluated for CLD. Hepatorenal syndrome was more common in subjects evaluated for AAH (37/47) than CLD (104/163) (78.7 versus 63.8%, p = 0.04). For the primary outcome, AAHHRS subjects required ⩾30 days post-LT renal replacement therapy (RRT) more often than subjects with CLDHRS (p = 0.02) and CLDno HRS (p < 0.01). There was no significant difference in other forms of long-term renal outcomes including kidney transplant referral and kidney transplant among cohorts. In subgroup analysis, 30-days post-LT RRT was more common in AAHHRS than in A-CLDHRS (p = 0.08). Logistic regression showed that AAHHRS conferred a 20× and 3.3× odds of requiring ⩾30 days post-LT RRT compared to CLDno HRS and CLDHRS, respectively. Postoperative complications were similar across cohorts, but had a significant effect on 30-day renal outcome post-LT.

Conclusions

Patients with AAH were more likely to develop HRS and require RRT pre- and post-LT at our center. The etiology of hepatic decompensation and postoperative complications affect renal recovery post-LT. The systemic inflammation of AAH in addition to conditions favoring renal hypoperfusion may contribute to the unfavorable outcomes of HRS-AKI after LT in this patient population.

Update on Assessment of Estimated Glomerular Filtration Rate in Patients With Cirrhosis

Kidney disease is associated with adverse outcomes in patients with cirrhosis including increased post-liver transplantation (LT) mortality. Therefore, diagnosis and staging of kidney disease are critical to timely implementation of treatment and have important implications for transplant eligibility. Serum creatinine (sCr) is a key component of the Model for End-Stage Liver Disease score in LT candidates, and sCr-based estimated glomerular filtration rate (eGFR) values play an important role in determining medical urgency for LT. However, the use of sCr to assess kidney function may be limited in the cirrhotic milieu due to decreased creatinine production, interference of bilirubin with some laboratory assays for sCr, and expansion of the volume of distribution of creatinine. Therefore, conventional eGFR equations perform poorly in patients with cirrhosis and may overestimate kidney function leading to delayed diagnosis of acute kidney injury or lower priority for LT in patients with a truly low glomerular filtration rate. In this review, we will provide an update on the use of sCr for diagnosis and staging of kidney disease in patients with cirrhosis, discuss the limitations of sCr-based eGFR equations, and discuss novel eGFR equations that have been developed in patients with cirrhosis.

CIRRHOTIC PATIENTS WITH ACUTE KIDNEY INJURY (AKI) HAVE HIGHER MORTALITY AFTER ABDOMINAL HERNIA SURGERY

BACKGROUND

The incidence of abdominal hernia in cirrhotic patients is as higher as 20%; in cases of major ascites the incidence may increase up to 40%. One of the main and most serious complications in cirrhotic postoperative period (PO) is acute kidney injury (AKI).

AIM

To analyze the renal function of cirrhotic patients undergoing to hernia surgery and evaluate the factors related to AKI.

METHODS

Follow-up of 174 cirrhotic patients who underwent hernia surgery. Laboratory tests including the renal function were collected in the PO.AKI was defined based on the consensus of the ascite´s club. They were divided into two groups: with (AKI PO) and without AKI .

RESULTS

All 174 patients were enrolled and AKI occurred in 58 (34.9%). In the AKI PO group, 74.1% had emergency surgery, whereas in the group without AKI PO it was only 34.6%.In the group with AKI PO, 90.4% presented complications, whereas in the group without AKI PO they occurred only in 29.9%. Variables age, baseline MELD, baseline creatinine, creatinine in immediate postoperative (POI), AKI and the presence of ascites were statistically significant for survival.

CONCLUSIONS

There is association between AKI PO and emergency surgery and, also, between AKI PO and complications after surgery. The factors related to higher occurrence were initial MELD, basal Cr, Cr POI. The patients with postoperative AKI had a higher rate of complications and higher mortality.

Regulator 1-Peroxisome Proliferator-Activated Receptor-γ Coactivator-1α Signaling Pathway in Investigating the Pathological Characteristics and Molecular Mechanism of Liver Cirrhosis Complicated by Acute Kidney Injury

The objective of this study was to investigate the molecular mechanism of the histopathological characteristics of liver cirrhosis (LC) complicated with acute kidney injury (AKI) and the signaling pathway of silent information regulator 1 (SIRT1)-peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) during the pathogenesis of LC. 20 healthy male rats with AKI complicated by laparoscopic cholecystectomy were selected and divided randomly into control group (C group), lipopolysaccharide (LPS) group, bile duct ligation (BDL) group, and model group (lipopolysaccharide+BDL) (D group). The indexes of all the rats were determined, including serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), sarcoplasmic enzyme (Scr), and blood urea nitrogen (BUN); the SIRT1 and PGC-1α expressions in renal tissues of rats from each group was detected. Results showed that the AST and ALT levels in BDL group and D group were higher markedly than those before surgery (P < 0.05). The serum levels of Scr and BUN in D group 4 hours after LPS injection increased hugely compared with before injection (P < 0.05). Compared with BDL group, the protein levels of SIRT1 and PGC-1α in renal tissue of group D were decreased sharply (P < 0.05), and the SIRT1 protein expression was positively correlated with PGC-1α (r = 0.836 and P < 0.01). When LC were complicated with AKI, SIRT1 activity was reduced and PGC-1α expression was inhibited. Moreover, SIRT1-PGC-1α signaling pathway played a protective role in pathogenesis of LC complicated with AKI.

An Integrated Review of the Hepatorenal Syndrome

Among the complications of cirrhosis, hepatorenal syndrome (HRS) is characterized by having the worst survival rate. HRS is a disorder that involves the deterioration of kidney function caused primarily by a systemic circulatory dysfunction, but in recent years, systemic inflammation and cirrhotic cardiomyopathy have been discovered to also play an important role. The diagnosis of HRS requires to meet the new International Club of Ascites-Acute Kidney Injury (ICA-AKI) and Hepatorenal Syndrome-Acute Kidney Injury (HRS-AKI) criteria after ruling out other causes of kidney injury. At the time of diagnosis, it is important to start the medical treatment as soon as possible where three types of vasoconstrictors have been recognized: vasopressin analogs (ornipressin and terlipressin), alpha-adrenergic agonists (norepinephrine and midodrine) and somatostatin analogues (octreotide); all should be combined with albumin infusion. Among them, terlipressin and albumin are the first lines of treatment in most cases, although terlipressin should be monitor closely due to its adverse events. The best treatment of choice is a liver transplant, because it is the only definitive treatment for this disease.

Acute kidney injury and continuous renal replacement therapy: A nursing perspective for my shift today in the intensive care unit

Handover, clinical discussion, and care for patients in the Intensive Care Unit (ICU) require visual cues to a verbal "story" in an attempt to quickly understand the patient status. Continuous renal replacement therapy (CRRT) is often associated with sepsis or a toxic cause and "kidney attack" not apparent to the patient; "silent" with no pain, discomfort, or vital sign changes initially. Language, terminology, and definitions for this acute kidney injury (AKI) are a graded classification with guidelines. CRRT and dialysis techniques use the physiological principles of diffusion and or convection for solute removal providing a replacement for the basic kidney functions to sustain life until function returns. When to stop CRRT is based on clinical assessment of the patient overall status and urine production re-starting. The medical treatment is focused on the key interventions of resuscitation, remove the cause, support with CRRT or dialysis and monitor for recovery of function. CRRT requires a multidisciplinary team and quality process, local policies, education, and competency pathways to promote best outcomes and efficacy.

Acute kidney injury among medical and surgical in-patients in the Cape Coast Teaching Hospital, Cape Coast, Ghana: a prospective cross-sectional study

Background

Acute kidney injury (AKI) is a syndrome associated with high morbidity, mortality and high hospital costs. Despite its adverse clinical and economic effects, only a few studies have reported reliable estimates on the incidence of AKI in sub-Sahara Africa. We assessed the incidence and associated factors of AKI among medical and surgical patients admitted to a tertiary hospital in Ghana.

Methods

A prospective cross-sectional study was conducted among one hundred and forty-five (145) consecutive patients admitted to the medical and the surgical wards at the Cape Coast Teaching Hospital (CCTH), Cape Coast, Ghana from April 2017 to April 2018. Socio-demographic and clinical information were collected using structured questionnaires. AKI was diagnosed and staged with the KDIGO guideline, using admission serum creatinine as baseline kidney function.

Results

The mean age of the study participants was 46.6±17.7 years, whilst the male:female ratio was 68:77. The overall incidence of AKI among the participants was 15.9% (95% CI: 10.33 – 22.84%). Stage 1 AKI occurred in 56.5% of the participants, whilst stages 2 and 3 AKI respectively occurred among 4.1% and 2.8% of respondents. About 20% of the participants in the medical ward developed AKI (n= 15) whilst 12% of those in surgical ward developed AKI (n= 8). Among the participants admitted to the medical ward, 60.0%, 26.7% and 13.3% had stages 1, 2 and 3 AKI respectively. Whilst 50.0%, 25.0% and 25.0% respectively developed stages 1, 2 and 3 AKI in the surgical ward. Medical patients with AKI had hypertension (40%), followed by liver disease (33.3%); 37.5% of surgical inpatients had gastrointestinal (GI) disorders.

Conclusion

The incidence of AKI is high among medical and surgical patients in-patients in the CCTH, Ghana, with hypertension and liver disease as major comorbidities.

Target delivery of drug carriers in mice kidney glomeruli via renal artery. Balance between efficiency and safety

Targeting drug delivery systems is crucial to reducing the side effects of therapy. However, many of them are lacking effectiveness for kidney targeting, due to systemic dispersion and accumulation in the lungs and liver after intravenous administration. Renal artery administration of carriers provides their effective local accumulation but may cause irreversible vessel blockage. Therefore, the combination of the correct administration procedure, suitable drug delivery system, selection of effective and safe dosage is the key to sparing local therapy. Here, we propose the 3-μm sized fluorescent capsules based on poly-L-arginine and dextran sulfate for targeting the kidney via a mice renal artery. Hemodynamic study of the target kidney in combination with the histological analysis reveals a safe dose of microcapsules (20 × 10⁶), which has not lead to irreversible pathological changes in blood flow and kidney tissue, and provides retention of 20.5 ± 3% of the introduced capsules in the renal cortex glomeruli. Efficacy of fluorescent dye localization in the target kidney after intra-arterial administration is 9 times higher than in the opposite kidney and after intravenous injection. After 24 h microcapsules are not observed in the target kidney when the safe dose of carriers is being used but a high level of fluorescent signal persists for 48 h indicating that fluorescent cargo accumulation in tissues. Injection of non-safe microcapsule dose leads to carriers staying in glomeruli for at least 48 h which has consequences of blood flow not being restored and tissue damage being observed in histology.

Prevalence and short-term outcome of hepatorenal syndrome: A 9-year experience in a high-complexity hospital in Colombia

BACKGROUND & AIMS

Hepatorenal syndrome is a rare entity that is part of the complications of liver cirrhosis in its more severe stages. Without treatment, its mortality rate increases significantly. Terlipressin is considered to be the therapy of choice until the need of a liver transplant. The aim is to determine its prevalence, define patients' characteristics, triggers and 90-day survival, according to the type of managements established.

METHOD

This was a retrospective cohort study conducted in Colombia. It included patients with cirrhosis and acute kidney injury who met hepatorenal syndrome criteria, reaching 28 patients from 2007 to 2015. Groups were categorized according the type of hepatorenal syndrome and treatment. Demographic and trigger factors were evaluated to characterize the population. Treatment outcomes with terlipressin vs norepinephrine were analyzed up to a 90-day survival, using log Rank test. Continuous variables needed Student's T and Mann Whitney's U tests and categorical variables, Chi2 test. A value of p <0.05 and a power of 85% was considered. The data was analyzed in the SPSS version 23 software.

RESULTS

117 patients with cirrhosis developed renal injury; of these 23.9% were diagnosed with Hepatorenal Syndrome (67.8% type1; 32.1% type2). The presence of ascites was 100% in HRS2 and 84% in HRS1 (p = 0.296). The main trigger in both types was paracentesis greater than 5 liters in the last 4 weeks (39.3%). In total, 35% of the patients received renal replacement therapy and 14% underwent a hepatic transplant. Type 1 was more frequent (63% received terlipressin; 21% norepinephrine). The total complete response was 36% (Type2 66.6% vs. Type1 18.7%) (p = 0.026). In contrast, the overall mortality was of 67.8% at 90-day of follow-up (89.4% Type1 vs. 22% Type2) (p = <0.001). We found a lower mortality rate in patients treated with terlipressin than treated with norepinephrine (p = 0.006).

CONCLUSION

There is scarce clinical and epidemiological information about this condition in Colombia. A significant difference between the two drugs cannot be stipulated due to the limitation in the sample size of our study. The general mortality at a 90-day follow-up was high, being higher in patients with HRS1. While the results of this study are suggestive of clinical information for HRS patients in the Colombian population, they should also be interpreted with caution, therefore further multicenter studies should be performed.

Reappraising the spectrum of AKI and hepatorenal syndrome in patients with cirrhosis

The occurrence of acute kidney injury (AKI) in patients with end-stage liver disease constitutes one of the most challenging clinical scenarios in in-hospital and critical care medicine. Hepatorenal syndrome type 1 (HRS-1), which is a specific type of AKI that occurs in the context of advanced cirrhosis and portal hypertension, is associated with particularly high mortality. The pathogenesis of HRS-1 is largely viewed as a functional derangement that ultimately affects renal vasculature tone. However, new insights suggest that non-haemodynamic tubulo-toxic factors, such as endotoxins and bile acids, might mediate parenchymal renal injury in patients with cirrhosis, suggesting that concurrent mechanisms, including those traditionally associated with HRS-1 and non-traditional factors, might contribute to the development of AKI in patients with cirrhosis. Moreover, histological evidence of morphological abnormalities in the kidneys of patients with cirrhosis and renal dysfunction has prompted the functional nature of HRS-1 to be re-examined. From a clinical perspective, a diagnosis of HRS-1 guides utilization of vasoconstrictive therapy and decisions regarding renal replacement therapy. Patients with cirrhosis are at risk of AKI owing to a wide range of factors. However, the tools currently available to ascertain the diagnosis of HRS-1 and guide therapy are suboptimal. Short of liver transplantation, goal-directed haemodynamically targeted pharmacotherapy remains the cornerstone of treatment for this condition; improved understanding of the underlying pathogenic mechanisms might lead to better clinical outcomes. Here, we examine our current understanding of the pathophysiology of HRS-1 and existing challenges in its diagnosis and treatment.

Urinary abnormalities in children and adolescents with Wilson disease before and during treatment with d-penicillamine

BACKGROUND AND AIM

Renal abnormalities can occur at any time point during the course of Wilson disease (WD). We aimed to fill a literature gap in this respect by studying urinary abnormalities in children and adolescents with WD.

METHODS

This study included 60 children with WD presenting to the Pediatric Hepatology Unit, Cairo University. The following data were retrieved from the patients' files including age, sex, liver function tests, serum ceruloplasmin, 24-h urinary copper, serum creatinine, blood urea nitrogen, urinalysis, urinary albumin/creatinine ratio, urinary calcium/creatinine ratio, urinary β2-microglobulin, liver and renal biopsy results when available.

RESULTS

All studied cases had no symptoms related to renal involvement. Microscopic hematuria was detected in 11% and 12% at baseline and within 5 years of therapy, respectively. Moderate microalbuminuria was detected in 34%, 50%, and 33% at baseline, within 5 years and > 5 years after therapy, respectively. Hypercalciuria was detected in 23% at baseline, 34% in those patients treated for up to 5 years and 37.5% > 5 years of therapy. Age and international normalized ratio were significantly higher in patients with high calcium/creatinine ratio compared with those with normal values at initial evaluation. Frequency of elevated urinary β2-microglobulin was 36%, 36%, and 37% in patients at baseline, up to 5 years and > 5 years of therapy, respectively.

CONCLUSION

Asymptomatic urinary abnormalities are present in patients with WD at any time point of the disease and during treatment with d-penicillamine. They have to be searched for, as early intervention may prevent progression to renal insufficiency.

Evaluation of Absolute Serum Creatinine Changes in Staging of Cirrhosis-Induced Acute Renal Injury and its Association with Long-term Outcomes

BACKGROUND/AIMS

To assess the prognostic accuracy of absolute serum creatinine (sCr) changes ('Delta-sCr') on the long-term outcomes in cirrhotic patients, and evaluate the performance of the 'Delta-sCr' approach to stage acute kidney injury (AKI), compared with the Kidney Disease Improving Global Outcomes (KDIGO) criteria.

METHODS

We conducted a retrospective analysis of 333 hospitalized patients. We classified AKI stages using two methods: 1) KDIGO AKI criteria; 2) 'Delta-sCr' system, defined by the difference between the baseline and the peak sCr value during the hospitalization. The end point was the hazard of 1-year death.

RESULTS

The prevalence of AKI in cirrhotic patients was 18.01% by the KDIGO criteria, and 25.22% by the 'Delta-sCr' system. On multivariable Cox hazard analysis, both of the two methods were independent predictive factors of death ('Delta-sCr' system: OR=2.911, p<0.001), (KDIGO criteria: OR=2.065, p<0.001). However, the 'Delta-sCr' system provided a modest improvement in classification over the KDIGO criteria with a net reclassification improvement (NRI) of 28.7% (p<0.001) and integrated discrimination improvement (IDI) of 7.5% (p=0.03). And the predictive value of the 'Delta-sCr' system could be significantly improved (p=0.006), when combined with age and MELD score.

CONCLUSION

The Delta-sCr is associated with the 1-year mortality. And the 'Delta-sCr' system may optimize the discrimination of risk prediction.

Special populations: treating hepatitis C in patients with decompensated cirrhosis and/or advanced renal impairment

Direct-acting antivirals have revolutionized the treatment of hepatitis C. Sustained virological response rates of at least 95% have become common in the general population. However, along with the ageing of the HCV population, physicians face a growing group of HCV-infected patients with advanced liver and/or renal impairment. The safety and efficacy of treatment remains a clinical challenge in these patients. This review focuses on the current state of knowledge and treatment regimens in patients with decompensated cirrhosis and severe renal impairment. It shows that distinct interferon-free treatments can achieve favourable sustained virological response rates in these difficult-to-treat patients. Moreover, pitfalls and special considerations as well as new emerging challenges in an era of interferon-free regimens will be presented in this article.

Presepsin teardown - pitfalls of biomarkers in the diagnosis and prognosis of bacterial infection in cirrhosis

AIM

To evaluate the diagnostic and prognostic value of presepsin in cirrhosis-associated bacterial infections.

METHODS

Two hundred and sixteen patients with cirrhosis were enrolled. At admission, the presence of bacterial infections and level of plasma presepsin, serum C-reactive protein (CRP) and procalcitonin (PCT) were evaluated. Patients were followed for three months to assess the possible association between presepsin level and short-term mortality.

RESULTS

Present 34.7 of patients had bacterial infection. Presepsin levels were significantly higher in patients with infection than without (median, 1002 pg/mL vs 477 pg/mL, P < 0.001), increasing with the severity of infection [organ failure (OF): Yes vs No, 2358 pg/mL vs 710 pg/mL, P < 0.001]. Diagnostic accuracy of presepsin for severe infections was similar to PCT and superior to CRP (AUC-ROC: 0.85, 0.85 and 0.66, respectively, P = NS for presepsin vs PCT and P < 0.01 for presepsin vs CRP). At the optimal cut-off value of presepsin > 1206 pg/mL sensitivity, specificity, positive predictive values and negative predictive values were as follows: 87.5%, 74.5%, 61.8% and 92.7%. The accuracy of presepsin, however, decreased in advanced stage of the disease or in the presence of renal failure, most probably because of the significantly elevated presepsin levels in non-infected patients. 28-d mortality rate was higher among patients with > 1277 pg/mL compared to those with ≤ 1277 pg/mL (46.9% vs 11.6%, P < 0.001). In a binary logistic regression analysis, however, only PCT (OR = 1.81, 95%CI: 1.09-3.01, P = 0.022) but neither presepsin nor CRP were independent risk factor for 28-d mortality after adjusting with MELD score and leukocyte count.

CONCLUSION

Presepsin is a valuable new biomarker for defining severe infections in cirrhosis, proving same efficacy as PCT. However, it is not a useful marker of short-term mortality.