Impact of acute kidney injury on the risk of mortality in patients with cirrhosis: a systematic review and meta-analysis

Effects of 24-hour urine-output trajectories on the risk of acute kidney injury in critically ill patients with cirrhosis: a retrospective cohort analysis

BACKGROUND

Acute kidney injury (AKI) is one of the most common complications for critically ill patients with cirrhosis, but it has remained unclear whether urine output fluctuations are associated with the risk of AKI in such patients. Thus, we explored the influence of 24-h urine-output trajectory on AKI in patients with cirrhosis through latent category trajectory modeling.

MATERIALS AND METHODS

This retrospective cohort study examined patients with cirrhosis using the MIMIC-IV database. Changes in the trajectories of urine output within 24 h after admission to the intensive care unit (ICU) were categorized using latent category trajectory modeling. The outcome examined was the occurrence of AKI during ICU hospitalization. The risk of AKI in patients with different trajectory classes was explored using the cumulative incidence function (CIF) and the Fine-Gray model with the sub-distribution hazard ratio (SHR) and the 95% confidence interval (CI) as size effects.

RESULTS

The study included 3,562 critically ill patients with cirrhosis, of which 2,467 (69.26%) developed AKI during ICU hospitalization. The 24-h urine-output trajectories were split into five classes (Classes 1-5). The CIF curves demonstrated that patients with continuously low urine output (Class 2), a rapid decline in urine output after initially high levels (Class 3), and urine output that decreased slowly and then stabilized at a lower level (Class 4) were at higher risk for AKI than those with consistently moderate urine output (Class 1). After fully adjusting for various confounders, Classes 2, 3, and 4 were associated with a higher risk of AKI compared with Class 1, and the respective SHRs (95% CIs) were 2.56 (1.87-3.51), 1.86 (1.34-2.59), and 1.83 1.29-2.59).

CONCLUSIONS

The 24-h urine-output trajectory is significantly associated with the risk of AKI in critically ill patients with cirrhosis. More attention should be paid to the dynamic nature of urine-output changes over time, which may help guide early intervention and improve patients' prognoses.

Acute kidney injury development is associated with mortality in Japanese patients with cirrhosis: impact of amino acid imbalance

BACKGROUND

Acute kidney injury (AKI) is a serious complication of cirrhosis. This study analyzed the prognostic effect of AKI in patients with cirrhosis and its risk factors, particularly in relation to amino acid imbalance.

METHODS

This retrospective study reviewed 808 inpatients with cirrhosis at two institutes in Gifu, Japan. AKI was diagnosed according to the recommendations of the International Club of Ascites. Amino acid imbalance was assessed by measuring serum branched-chain amino acid (BCAA) levels, tyrosine levels, and the BCAA-to-tyrosine ratio (BTR). Factors associated with mortality and AKI development were assessed using the Cox proportional hazards regression model with AKI as a time-dependent covariate and the Fine-Gray competing risk regression model, respectively.

RESULTS

Of the 567 eligible patients without AKI at baseline, 27% developed AKI and 25% died during a median follow-up period of 4.7 years. Using a time-dependent covariate, AKI development (hazard ratio [HR], 6.25; 95% confidence interval [CI], 3.98-9.80; p < 0.001) was associated with mortality in patients with cirrhosis independent of potential covariates. In addition, alcohol-associated/-related liver disease, metabolic dysfunction-associated steatohepatitis, Child-Pugh score, and BTR (subdistribution HR 0.78; 95% CI 0.63-0.96; p = 0.022) were independently associated with AKI development in patients with cirrhosis. Similar results were obtained in the multivariate model that included BCAA and tyrosine levels instead of BTR.

CONCLUSIONS

AKI is common and associated with mortality in Japanese patients with cirrhosis. An amino acid imbalance is strongly associated with the development of AKI in patients with cirrhosis.

The Renin-Angiotensin System in Liver Disease

The renin-angiotensin system (RAS) is a complex homeostatic entity with multiorgan systemic and local effects. Traditionally, RAS works in conjunction with the kidney to control effective arterial circulation, systemic vascular resistance, and electrolyte balance. However, chronic hepatic injury and resulting splanchnic dilation may disrupt this delicate balance. The role of RAS in liver disease, however, is even more extensive, modulating hepatic fibrosis and portal hypertension. Recognition of an alternative RAS pathway in the past few decades has changed our understanding of RAS in liver disease, and the concept of opposing vs. "rebalanced" forces is an ongoing focus of research. Whether RAS inhibition is beneficial in patients with chronic liver disease appears to be context-dependent, but further study is needed to optimize clinical management and reduce organ-specific morbidity and mortality. This review presents the current understanding of RAS in liver disease, acknowledges areas of uncertainty, and describes potential areas of future investigation.

Hepatorenal syndrome misdiagnosis may be reduced using inferior vena cava ultrasound to assess intravascular volume and guide management

Hepatorenal syndrome (HRS) is a diagnosis of exclusion defined as acute kidney injury (AKI) with cirrhosis and ascites, with serum creatinine unresponsive to standardized volume administration and diuretic withdrawal. Persistent intravascular hypovolemia or hypervolemia may contribute to AKI and be revealed by inferior vena cava ultrasound (IVC US), which may guide additional volume management. Twenty hospitalized adult patients meeting HRS-AKI criteria had IVC US to assess intravascular volume after receiving standardized albumin administration and diuretic withdrawal. Six had IVC collapsibility index (IVC-CI) ≥50% and IVCmax ≤0.7 cm suggesting intravascular hypovolemia, 9 had IVC-CI <20% and IVCmax >0.7 cm suggesting intravascular hypervolemia, and 5 had IVC-CI ≥20% to <50% and IVCmax >0.7 cm. Additional volume management was prescribed in the 15 patients with either hypovolemia or hypervolemia. After 4-5 days, serum creatinine levels decreased ≥20% without hemodialysis in 6 of 20 patients - 3 with hypovolemia received additional volume, and 2 with hypervolemia plus one with 'euvolemia' and dyspnea were volume restricted and received diuretics. In the other 14 patients, serum creatinine failed to persistently decrease ≥20% or hemodialysis was required indicating that AKI did not improve. In summary, fifteen of 20 patients (75%) were presumed to have intravascular hypovolemia or hypervolemia by IVC ultrasound. Six of the 20 patients (40%) improved AKI by 4-5 days of follow-up with additional IVC US-guided volume management, and thus had been misdiagnosed as HRS-AKI. IVC US may more accurately define HRS-AKI as being neither hypovolemic nor hypervolemic, and guide volume management, decreasing the frequency of HRS-AKI misdiagnosis.

Prediction models combining zonulin, LPS, and LBP predict acute kidney injury and hepatorenal syndrome-acute kidney injury in cirrhotic patients

The development of acute kidney injury (AKI) and hepatorenal syndrome-acute kidney injury (HRS-AKI) in cirrhosis has been associated with intestinal barrier dysfunction and gut-kidney crosstalk. We use the related markers such as zonulin, lipopolysaccharides (LPS), and lipopolysaccharide-binding protein (LBP) to predict AKI and HRS-AKI in cirrhotic patients and evaluate their in vitro effects on intestinal (Caco-2) cells and renal tubular (HK-2) cells. From 2013 to 2020, we enrolled 70 cirrhotic patients and developed prediction models for AKI and HRS-AKI over a six-month period. There were 13 (18.6%) and 8 (11.4%) cirrhotic patients developed AKI and HRS-AKI. The prediction models incorporated zonulin, LPS, LBP, C-reactive protein, age, and history of hepatitis B for AKI, and zonulin, LPS, LBP, total bilirubin, and Child-Pugh score for HRS-AKI. The area under curve (AUC) for the prediction of AKI and HRS-AKI was 0.94 and 0.95, respectively. Furthermore, the conditioned medium of LPS+hrLBP pre-treated Caco-2 cells induced apoptosis, necrosis, and zonulin release in HK-2 cells, demonstrating the communication between them. This study found that zonulin, LPS, and LBP are potential practical markers for predicting AKI and HRS-AKI in cirrhotic patients, which may serve as potential targets for renal outcomes in cirrhotic patients.

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.

Acute kidney injury development and impact on clinical and economic outcomes in patients with cirrhosis: an observational cohort study over a 10-year period

OBJECTIVES

Acute kidney injury (AKI) is a severe complication that is associated with significant morbidity and mortality in hospitalized cirrhotic patients. Data about AKI incidence and outcomes in patients with cirrhosis is scarce in the Middle East region. This study explored the incidence and impact of AKI on clinical and economic outcomes in cirrhosis.

METHODS

This was a retrospective cohort study of cirrhosis patients admitted to an educational hospital in Jordan during the years 2012-2022. Demographics, clinical and biochemical information, and charges were retrieved from medical electronic records. Logistic regression models were conducted to evaluate predictors of AKI and mortality in cirrhosis adjusting for covariates. Hospital charges were also described.

RESULTS

A total of 380 cirrhosis patients were included with an AKI incidence of 27.9%. Male sex, elevated baseline serum creatinine, presence of spontaneous bacterial peritonitis, and higher comorbidity score were independently associated with AKI development ( P < 0.05). The hospital mortality rate was markedly higher for patients with AKI versus those without AKI (51.9% vs. 6.2%, respectively; P < 0.001). AKI was associated independently with higher odds of hospital death (OR = 5.83, P < 0.001), prolongation of the median hospital stays by 5 days ( P < 0.001), more clinical complications, and increased total hospital charges per admission by $2500.

CONCLUSION

AKI is prevalent in cirrhosis patients, and it is associated with increased mortality, hospitalization, and cost. This burden in cirrhosis emphasizes the need for early identification of patients at high risk of AKI and applying prompt and effective management approaches, aiming at improving outcomes.