Association of AKI with mortality and complications in hospitalized patients with cirrhosis

Urinary biomarkers and progression of AKI in patients with cirrhosis

BACKGROUND AND OBJECTIVES

AKI is a common and severe complication in patients with cirrhosis. AKI progression was previously shown to correlate with in-hospital mortality. Therefore, accurately predicting which patients are at highest risk for AKI progression may allow more rapid and targeted treatment. Urinary biomarkers of structural kidney injury associate with AKI progression and mortality in multiple settings of AKI but their prognostic performance in patients with liver cirrhosis is not well known.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A multicenter, prospective cohort study was conducted at four tertiary care United States medical centers between 2009 and 2011. The study comprised patients with cirrhosis and AKI defined by the AKI Network criteria evaluating structural (neutrophil gelatinase-associated lipocalin, IL-18, kidney injury molecule-1 [KIM-1], liver-type fatty acid-binding protein [L-FABP], and albuminuria) and functional (fractional excretion of sodium [FENa]) urinary biomarkers as predictors of AKI progression and in-hospital mortality.

RESULTS

Of 188 patients in the study, 44 (23%) experienced AKI progression alone and 39 (21%) suffered both progression and death during their hospitalization. Neutrophil gelatinase-associated lipocalin, IL-18, KIM-1, L-FABP, and albuminuria were significantly higher in patients with AKI progression and death. These biomarkers were independently associated with this outcome after adjusting for key clinical variables including model of end stage liver disease score, IL-18 (relative risk [RR], 4.09; 95% confidence interval [95% CI], 1.56 to 10.70), KIM-1 (RR, 3.13; 95% CI, 1.20 to 8.17), L-FABP (RR, 3.43; 95% CI, 1.54 to 7.64), and albuminuria (RR, 2.07; 95% CI, 1.05-4.10) per log change. No biomarkers were independently associated with progression without mortality. FENa demonstrated no association with worsening of AKI. When added to a robust clinical model, only IL-18 independently improved risk stratification on a net reclassification index.

CONCLUSIONS

Multiple structural biomarkers of kidney injury, but not FENa, are independently associated with progression of AKI and mortality in patients with cirrhosis. Injury marker levels were similar between those without progression and those with progression alone.

Kidney injury in cirrhosis: pathophysiological and therapeutic aspects of hepatorenal syndromes

Acute kidney injury (AKI) is frequent in patients with cirrhosis. AKI and hyponatraemia are major determinants of the poor prognosis in advanced cirrhosis. The hepatorenal syndrome (HRS) denotes a functional and potential reversible impairment of renal function. Type 1 HRS, a special type of AKI, is a rapidly progressive AKI, whereas the renal function in type 2 HRS decreases more slowly. HRS is precipitated by factors such as sepsis that aggravate the effective hypovolaemia in decompensated cirrhosis, by lowering arterial pressure and cardiac output and enhanced sympathetic nervous activity. Therefore, attempts to prevent and treat HRS should seek to improve liver function and to ameliorate arterial hypotension, central hypovolaemia and cardiac output, and to reduce renal vasoconstriction. Ample treatment of HRS is important to prevent further progression and death, but as medical treatment only modestly improves long-term survival, these patients should always be considered for liver transplantation. Hyponatraemia, defined as serum sodium <130 mmol/L, is common in patients with decompensated cirrhosis. From a pathophysiological point of view, hyponatraemia is related to an impairment of renal solute-free water excretion most likely caused by an increased vasopressin secretion. Patients with cirrhosis mainly develop hypervolaemic hyponatraemia. Current evidence does not support routine use of vaptans in the management of hyponatraemia in cirrhosis.

Renal dysfunction in patients with cirrhosis: Where do we stand?

Patients with cirrhosis and renal failure are high-risk patients who can hardly be grouped to form precise instructions for diagnosis and treatment. When it comes to evaluate renal function in patients with cirrhosis, determination of acute kidney injury (AKI), chronic kidney disease (CKD) or AKI on CKD should be made. First it should be excluded the prerenal causes of AKI. All cirrhotic patients should undergo renal ultrasound for measurement of renal resistive index in every stage of liver dysfunction and urine microscopy for differentiation of all causes of AKI. If there is history of dehydration on the ground of normal renal ultrasound and urine microscopy the diuretics should be withdrawn and plasma volume expansion should be tried with albumin. If the patient does not respond, the correct diagnosis is HRS. In case there is recent use of nephrotoxic agents or contrast media and examination shows shock, granular cast in urinary sediment and proteinuria above 0.5 g daily, acute tubular necrosis is the prominent diagnosis. Renal biopsy should be performed when glomerular filtration rate is between 30-60 mL/min and there are signs of parenchymal renal disease. The acute renal function is preferable to be assessed with modified AKIN. Patients with AKIN stage 1 and serum creatinine ≥ 1.5 mg/dL should be at close surveillance. Management options include hemodynamic monitoring and management of fluid balance and infections, potentially driving to HRS. Terlipressin is the treatment of choice in case of established HRS, administered until there are signs of improvement, but not more than two weeks. Midodrine is the alternative for therapy continuation or when terlipressin is unavailable. Norepinephrine has shown similar effect with terlipressin in patients being in Intensive Care Unit, but with much lower cost than that of terlipressin. If the patient meets the requirements for transplantation, dialysis and transjugular intrahepatic portosystemic shunt are the bridging therapies to keep the transplant candidate in the best clinical status. The present review clarifies the latest therapeutic modalities and the proposed recommendations and algorithms in order to be applied in clinical practice.

Kidney biomarkers and differential diagnosis of patients with cirrhosis and acute kidney injury

Acute kidney injury (AKI) is common in patients with cirrhosis and associated with significant mortality. The most common etiologies of AKI in this setting are prerenal azotemia (PRA), acute tubular necrosis (ATN), and hepatorenal syndrome (HRS). Accurately distinguishing the etiology of AKI is critical, as treatments differ markedly. However, establishing an accurate differential diagnosis is extremely challenging. Urinary biomarkers of kidney injury distinguish structural from functional causes of AKI and may facilitate more accurate and rapid diagnoses. We conducted a multicenter, prospective cohort study of patients with cirrhosis and AKI assessing multiple biomarkers for differential diagnosis of clinically adjudicated AKI. Patients (n = 36) whose creatinine returned to within 25% of their baseline within 48 hours were diagnosed with PRA. In addition, 76 patients with progressive AKI were diagnosed by way of blinded retrospective adjudication. Of these progressors, 39 (53%) patients were diagnosed with ATN, 19 (26%) with PRA, and 16 (22%) with HRS. Median values for neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18), kidney injury molecule-1 (KIM-1), liver-type fatty acid binding protein (L-FABP), and albumin differed between etiologies and were significantly higher in patients adjudicated with ATN. The fractional excretion of sodium (FENa) was lowest in patients with HRS, 0.10%, but did not differ between those with PRA, 0.27%, or ATN, 0.31%, P = 0.54. The likelihood of being diagnosed with ATN increased step-wise with the number of biomarkers above optimal diagnostic cutoffs.

CONCLUSION

Urinary biomarkers of kidney injury are elevated in patients with cirrhosis and AKI due to ATN. Incorporating biomarkers into clinical decision making has the potential to more accurately guide treatment by establishing which patients have structural injury underlying their AKI. Further research is required to document biomarkers specific to HRS.

Urinary neutrophil gelatinase-associated lipocalin predicts kidney outcome and death in patients with cirrhosis and bacterial infections

BACKGROUND & AIMS

Infections in cirrhosis are frequently complicated by kidney dysfunction that entails a poor prognosis. Urinary biomarkers may be of potential clinical usefulness in this setting. We aimed at assessing the value of urinary neutrophil gelatinase-associated lipocalin (uNGAL), a biomarker overexpressed in kidney tubules during kidney injury, in predicting clinical outcomes in cirrhosis with infections.

METHODS

One-hundred and thirty-two consecutive patients hospitalized with infections were evaluated prospectively. Acute kidney injury (AKI) was defined according to AKIN criteria. uNGAL was measured at infection diagnosis and at days 3 and 7 (ELISA, Bioporto, DK).

RESULTS

Patients with AKI (n=65) had significantly higher levels of uNGAL compared to patients without AKI (203 ± 390 vs. 79 ± 126 μg/g creatinine, p<0.001). Moreover, uNGAL levels were significantly higher in patients who developed persistent AKI (n=40), compared to those with transient AKI (n=25) (281 ± 477 vs. 85 ± 79 μg/g creatinine, p<0.001). Among patients with persistent AKI, uNGAL was able to discriminate type-1 HRS from other causes of AKI (59 ± 46 vs. 429 ± 572 μg/g creatinine, respectively; p<0.001). Moreover, the time course of uNGAL was markedly different between the two groups. Interestingly, baseline uNGAL levels also predicted the development of a second infection during hospitalization. Overall, 3-month mortality was 34%. Independent predictive factors of 3-month mortality were MELD score, serum sodium, and uNGAL levels at diagnosis, but not presence or stage of AKI.

CONCLUSIONS

In patients with cirrhosis and infections, measurement of urinary NGAL at infection diagnosis is useful in predicting important clinical outcomes, specifically persistency and type of AKI, development of a second infection, and 3-month mortality.

Hepatic hydrothorax: clinical features, management, and outcomes in 77 patients and review of the literature

Hepatic hydrothorax is an important and difficult-to-manage complication of cirrhosis and portal hypertension. Here, we aimed to study its clinical features and natural history. Complete clinical data, including outcomes, were abstracted from hospital records of patients with cirrhosis and ascites admitted to University of Texas Southwestern University teaching hospitals from January 2001 to July 2012. Hepatic hydrothorax was diagnosed based on currently accepted clinical characteristics of the disease, including a known diagnosis of cirrhosis, the presence of portal hypertension, pleural fluid analysis, and the absence of primary cardiopulmonary disease.Seventy-seven of 495 (16%) hospitalized cirrhotic patients with pleural effusion (28 female; mean age, 52 yr) met the criteria for diagnosis of hepatic hydrothorax. Resting dyspnea and cough were the most prominent presenting symptoms, occurring in 34% and 22% of patients, respectively. Pleural effusions were most often right-sided (56/77; 73%), followed by left-sided only (13/77; 17%) and bilateral effusions (8/77; 10%); 7 (9%) patients did not have detectable ascites. The mean Model for End-Stage Liver Disease (MELD) score at presentation was 16. The serum to pleural fluid albumin gradient (SPAG) was ≥1.1 in all 48 patients in whom it was measured. Most patients (64/77; 83%) were managed with diuretics and/or thoracentesis, while 8 (10%) underwent transjugular intrahepatic portosystemic shunt (TIPS) and 5 (7%) underwent liver transplant. A total of 44 of 77 (57%) patients died during a mean follow-up of 12 months. The average time from presentation to death for all patients was 368 days, while for those after TIPS it was 845 days. No deaths were reported in the liver transplant group. The data indicate that a substantial number of patients with hepatic hydrothorax had what may be considered atypical presentations, including left-sided only effusions, or pleural effusion without ascites. Here, we propose that the term "serum to pleural fluid albumin gradient (SPAG)" be used to describe the gradient between serum and pleural fluid albumin levels and suggest that not only is it consistent with the portal hypertensive pathophysiology of hepatic hydrothorax, but also it is a useful criterion for diagnosis of hepatic hydrothorax. Finally, the overall outcome of hepatic hydrothorax was extremely poor, except in those undergoing TIPS or liver transplantation.

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.

Evaluation of renal function in patients with cirrhosis: Where are we now?

In the clinical context of the patients with liver cirrhosis, accurate evaluation of the renal function is potentially crucial. Indeed, it can lead to early diagnosis of both acute kidney injury and chronic kidney disease and to reliable characterization of the renal status of the patient before performing a liver transplantation. Despite some limitations, the assay of serum creatinine (SCr) is universally used to estimate glomerular filtration rate (GFR) because of its wide availability, its simplicity and because it is inexpensive. Nevertheless, several reports show that the value of this assay to estimate GFR is strongly challenged in cirrhotic patients, especially in patients with liver failure and/or severely impaired renal function. This has led to seek new alternatives to estimate more reliably the GFR in these patients. Although the reference methods, based on the utilization of exogenous markers, allow measuring GFR and thereby constitute the “gold standard” to evaluate renal function, they are not feasible in routine clinical practice. Several studies have shown that a cystatin C (CysC) based formula perform better than the SCr-based estimates in cirrhotic patients and the estimation of GFR by these formulas could therefore lead to optimize the management of the patients. A new estimate based on CysC has been recently developed using a large number of patients and the first results regarding the evaluation of its performance are promising, making this new formula the best candidate for a reference estimate of the renal function in cirrhotic patients.

Risk factors and outcome of bacterial infections in cirrhosis

Viable and non-viable pathological bacterial translocation promote a self-perpetuating circle of dysfunctional immune activation and systemic inflammation facilitating infections and organ failure in advanced cirrhosis. Bacterial infections and sepsis are now recognized as a distinct stage in the natural progression of chronic liver disease as they accelerate organ failure and contribute to the high mortality observed in decompensated cirrhosis. The increasing knowledge of structural, immunological and hemodynamic pathophysiology in advanced cirrhosis has not yet translated into significantly improved outcomes of bacterial infections over the last decades. Therefore, early identification of patients at the highest risk for developing infections and infection-related complications is required to tailor the currently available measures of surveillance, prophylaxis and therapy to the patients in need in order to improve the detrimental outcome of bacterial infections in cirrhosis.

Acute kidney injury: quoi de neuf?

BACKGROUND

Acute kidney injury (AKI) is frequently encountered in the nephrology practice. Serum creatinine, with its many shortcomings, is still the main biomarker used to detect AKI.

METHODS

This review focuses on recent advances in definition, diagnosis, risk factors, and molecular mechanisms of AKI. In addition, specific AKI syndromes such as contrast-induced AKI, hepatorenal syndrome, and acute decompensated heart failure are discussed. The connection between AKI and subsequent chronic kidney disease and recent developments in renal replacement therapy are also covered.

RESULTS

Novel biomarkers such as cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) are being investigated to replace serum creatinine in the detection of AKI. Recent studies suggest that intravenous (IV) fluid use is beneficial for the prevention of contrast-induced AKI, while N-acetylcysteine use is not as well established. Diuretics are clearly beneficial in the treatment of acute decompensated heart failure. Ultrafiltration is less promising and can lead to adverse side effects. Although terlipressin use in hepatorenal syndrome is associated with reduced mortality, it is not available in the United States; combination therapy with midodrine, octreotide, and albumin provides an alternative. Fluid resuscitation is frequently used in critically ill patients with AKI; however, overly aggressive fluid resuscitation is frequently associated with an increased risk of mortality. A 3-step approach that combines guided fluid resuscitation, establishment of an even fluid balance, and an appropriate rate of fluid removal may be beneficial. If fluid resuscitation is needed, crystalloid solutions are preferred over hetastarch solutions. Renal replacement therapy is the last resort in AKI treatment, and timing, modality, and dosing are discussed. Research suggests that AKI leads to an increased incidence of subsequent chronic kidney disease. However, this relationship has not been fully established and additional studies are needed for clarification.

CONCLUSION

Despite major advances in AKI research, serum creatinine remains the major biomarker for the detection of AKI. The following interventions have shown to be beneficial: IV fluids for contrast-induced AKI; diuretics for acute decompensated heart failure/cardiorenal syndrome; and combination therapy with midodrine, octreotide, and albumin for hepatorenal syndrome. Fluid resuscitation in a patient with AKI should be used with caution because too liberal use of fluids can be associated with increased mortality. AKI appears to be related to increased rates of subsequent chronic kidney disease, and patients with AKI should therefore be monitored closely. Recent studies on renal replacement therapy have neither revealed an optimal timing for initiation of dialysis nor a clear advantage for a specific dialysis modality.

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%.

New consensus definition of acute kidney injury accurately predicts 30-day mortality in patients with cirrhosis and infection

BACKGROUND & AIMS

Participants at a consensus conference proposed defining cirrhosis-associated acute kidney injury (AKI) based on a >50% increase in serum creatinine level from the stable baseline value in <6 months or an increase of ≥ 0.3 mg/dL in <48 hours. We performed a prospective study to evaluate the ability of these criteria to predict mortality within 30 days of hospitalization among patients with cirrhosis and infection.

METHODS

We followed up 337 patients with cirrhosis who were admitted to the hospital with an infection or developed an infection during hospitalization (56% men; 56 ± 10 years of age; Model for End-Stage Liver Disease [MELD] score, 20 ± 8) at 12 centers in North America. We compared data on 30-day mortality, length of stay in the hospital, and organ failure between patients with and without AKI.

RESULTS

In total, based on the consensus criteria, 166 patients (49%) developed AKI during hospitalization. Patients who developed AKI were admitted with higher Child-Pugh scores than those who did not develop AKI (11.0 ± 2.1 vs 9.6 ± 2.1; P < .0001) as well as higher MELD scores (23 ± 8 vs 17 ± 7; P < .0001) and lower mean arterial pressure (81 ± 16 vs 85 ± 15 mm Hg; P < .01). Higher percentages of patients with AKI died within 30 days of hospitalization (34% vs 7%), were transferred to the intensive care unit (46% vs 20%), required ventilation (27% vs 6%), or went into shock (31% vs 8%); patients with AKI also had longer stays in the hospital (17.8 ± 19.8 vs 13.3 ± 31.8 days) (all P < .001). Of the AKI episodes, 56% were transient, 28% were persistent, and 16% resulted in dialysis. Mortality was higher among those without renal recovery (80%) compared with partial (40%) or complete recovery (15%) or those who did not develop AKI (7%; P < .0001).

CONCLUSIONS

Among patients with cirrhosis, 30-day mortality is 10-fold higher among those with irreversible AKI than those without AKI. The consensus definition of AKI accurately predicts 30-day mortality, length of hospital stay, and organ failure.

Prognostic scores for cirrhotic patients admitted to an intensive care unit: which consequences for liver transplantation?

Mortality is increased in cirrhotic patients admitted in ICU whatever the admission reason. Prognosis scores assessed in critically ill cirrhotic patients in ICU can be classified in three main categories: liver-specific (CTP and MELD) scores, general (SAPS II and APACHE) scores, and organ failure (OSF and SOFA) scores. The components of the liver-specific scores can be influenced by the acute disease indicating the admission to ICU but those of the non liver-specific scores can be influenced by the underlying liver cirrhosis. Many studies reported that organ failure scores are the best predictors of outcome in cirrhotic patients in ICU. We may wonder if cirrhotic patients with acute organ failures should receive prioritization for organ allocation to save their life or should be denied for a potential futile LT. According to recent studies, the SOFA score is associated with a higher risk of death for patients waiting for LT but could not be associated with a worse outcome after LT. It becomes of paramount importance to correctly identify the cirrhotic patients who will maximally benefit from LT after admission to ICU. The EASL-CLIF Consortium defines the CLIF-SOFA score, redefining the SOFA score with cut-off levels based on mortality prediction. The CLIF-SOFA could represent the ideal score in ICU since it is based on organ failures with cut-off values specifically identified in cirrhotic patients. The validation of the CLIF-SOFA score in critically ill cirrhotic patients admitted to ICU and its usefulness to identify patients who could benefit from LT should be the next steps.

Current concepts in the diagnosis and classification of renal dysfunction in cirrhosis

BACKGROUND

Renal dysfunction is one of the most common complications of cirrhosis with high morbidity and mortality.

SUMMARY

In subjects with cirrhosis, renal dysfunction can present either as a direct consequence of cirrhosis (e.g. hepatorenal syndrome type I and type II) or secondary to etiologies other than cirrhosis (chronic kidney disease due to diabetic nephropathy, prerenal azotemia), or patients with cirrhosis may have renal dysfunction resulting directly from cirrhosis and an underlying chronic kidney disease.

KEY MESSAGES

Given the challenges in the differential diagnosis of renal dysfunction and insufficient accuracy of serum creatinine and creatinine-based glomerular filtration rate estimating equations in cirrhosis, there is an urgent need for more accurate biomarkers of renal dysfunction in this population. This review will discuss novel concepts for the diagnosis and classification of renal dysfunction in cirrhosis to overcome at least some of the diagnostic and therapeutic challenges. Additionally, a new classification will be proposed for renal dysfunction in cirrhosis.

Non-hemorrhagic acute complications associated with cirrhosis and portal hypertension

Timely recognition and management of acute complications of cirrhosis is of significant importance in order to reduce morbidity and mortality, especially in the hospitalized patient. In this review, we present a practical approach to the identification and management of non-hemorrhagic acute complications of cirrhosis, specifically bacterial infections, acute kidney injury, and acute exacerbation of hepatic encephalopathy, focusing on patient stratification.

A modified acute kidney injury classification for diagnosis and risk stratification of impairment of kidney function in cirrhosis

BACKGROUND & AIMS

The Acute Kidney Injury Network (AKIN) criteria are widely used in nephrology, but information on cirrhosis is limited. We aimed at evaluating the AKIN criteria and their relationship with the cause of kidney impairment and survival.

METHODS

We performed a prospective study of 375 consecutive patients hospitalized for complications of cirrhosis. One-hundred and seventy-seven (47%) patients fulfilled the criteria of Acute Kidney Injury (AKI) during hospitalization, the causes being hypovolemia, infections, hepatorenal syndrome (HRS), nephrotoxicity, and miscellaneous (62, 54, 32, 8, and 21 cases, respectively).

RESULTS

At diagnosis, most patients had AKI stage 1 (77%). Both the occurrence of AKI and its stage were associated with 3-month survival. However, survival difference between stages 2 and 3 was not statistically significant. Moreover, if stage 1 patients were categorized into 2 groups according to the level of serum creatinine used in the classical definition of kidney impairment (1.5mg/dl), the two groups had a significantly different outcome. Combining AKIN criteria and maximum serum creatinine, 3 risk groups were identified: (A) patients with AKI stage 1 with peak creatinine ≤ 1.5mg/dl; (B) patients with stage 1 with peak creatinine >1.5mg/dl; and (C) patients with stages 2-3 (survival 84%, 68%, and 36%, respectively; p<0.001). Survival was independently related to the cause of kidney impairment, patients with HRS or infection-related having the worst prognosis.

CONCLUSIONS

A classification that combines the AKIN criteria and classical criteria of kidney failure in cirrhosis provides a better risk stratification than AKIN criteria alone. The cause of impairment in kidney function is key in assessing prognosis in cirrhosis.

The 22/11 risk prediction model: a validated model for predicting 30-day mortality in patients with cirrhosis and spontaneous bacterial peritonitis

OBJECTIVES

Clinicians do not have a validated tool for estimating the short-term mortality associated with spontaneous bacterial peritonitis (SBP). Accurate prognosis assessment is important for risk stratification and for individualizing therapy. We aimed therefore to develop and validate a model for the prediction of 30-day mortality in SBP patients receiving standard medical treatment (antibiotics and if indicated by guidelines, intravenous albumin therapy).

METHODS

We retrospectively identified SBP patients treated at a tertiary care center between 2003 and 2011 (training set). Multivariate regression modeling and receiver operating characteristic (ROC) curves were utilized for statistical analysis. An external data set of 109 SBP patients was utilized for validation.

RESULTS

Of the 184 patients in the training set, 66% were men with a median age of 55 years, a median MELD (Model for End-Stage Liver Disease) score of 20, and a 30-day mortality of 27%. Peripheral blood leukocyte count ≥11×10⁹ cells/l (odds ratio (OR) 2.5; 95% confidence interval CI: 1.2-5.2) and MELD score ≥22 (OR 4.6; 95% CI: 2.3-9.6) were independent predictors of 30-day mortality. Patients with neither, one, or both variables had 30-day mortality rates of 8%, 32%, and 52%, respectively. The findings in the validation set mirrored the training set.

CONCLUSIONS

In cirrhotic patients with SBP receiving standard therapy, MELD score ≥22 and peripheral blood leukocyte count ≥11×10⁹ cells/l are validated independent predictors of mortality. The mortality in a patient without either poor prognostic variable is ≤10% and with both variables is ≥50%. Trials aiming to reduce mortality should target patients in the moderate-risk to high-risk groups.

Evaluation of the Acute Kidney Injury Network criteria in hospitalized patients with cirrhosis and ascites

BACKGROUND & AIMS

For several years hepatologists have defined acute renal failure in patients with cirrhosis as an increase in serum creatinine (sCr) ≥ 50% to a final value of sCr>1.5mg/dl (conventional criterion). Recently, the Acute Kidney Injury Network (AKIN) defined acute renal failure as acute kidney injury (AKI) on the basis of an absolute increase in sCr of 0.3mg/dl or a percentage increase in sCr ≥ 50% providing also a staging from 1 to 3. AKIN stage 1 was defined as an increase in sCr ≥ 0.3mg/dl or increase in sCr ≥ 1.5-fold to 2-fold from baseline. AKI diagnosed with the two different criteria was evaluated for the prediction of in-hospital mortality.

METHODS

Consecutive hospitalized patients with cirrhosis and ascites were included in the study and evaluated for the development of AKI.

RESULTS

Conventional criterion was found to be more accurate than AKIN criteria in improving the prediction of in-hospital mortality in a model including age and Child-Turcotte-Pugh score. The addition of either progression of AKIN stage or a threshold value for sCr of 1.5mg/dl further improves the value of AKIN criteria in this model. More in detail, patients with AKIN stage 1 and sCr<1.5mg/dl had a lower mortality rate (p=0.03), a lower progression rate (p=0.01), and a higher improvement rate (p=0.025) than patients with AKIN stage 1 and sCr ≥ 1.5mg/dl.

CONCLUSIONS

Conventional criterion is more accurate than AKIN criteria in the prediction of in-hospital mortality in patients with cirrhosis and ascites. The addition of either the progression of AKIN stage or the cut-off of sCr ≥ 1.5mg/dl to the AKIN criteria improves their prognostic accuracy.

Acute kidney injury is independently associated with death in patients with cirrhosis

BACKGROUND AND AIMS

Current creatine-based criteria for defining acute kidney injury (AKI) are validated in general hospitalised patients but their application to cirrhotics (who are younger and have reduced muscle mass) is less certain. We aimed to evaluate current definitions of AKI (acute kidney injury network (AKIN) criteria) in a population of cirrhotic patients and correlate this with outcomes.

METHODS

We prospectively identified patients with AKI and clinical, radiological or histological evidence of cirrhosis. We compared them with a control group with evidence of cirrhosis and no AKI.

RESULTS

162 cirrhotic patients were studied with a mean age of 56.8±14 years. They were predominantly male (65.4%) with alcoholic liver disease (78.4%). 110 patients had AKI: 44 stage 1, 32 stage 2 and 34 stage 3. They were well matched in age, sex and liver disease severity with 52 cirrhotics without AKI. AKI was associated with increased mortality (31.8% vs 3.8%, p<0.001). Mortality increased with each AKI stage; 3.8% in cirrhotics without AKI, 13.5% stage 1, 37.8% stage 2 and 43.2% stage 3 (p<0.001 for trend). Worsening liver disease (Child-Pugh class) correlated with increased mortality: 3.1% class A, 23.6% class B and 32.8% class C (p=0.006 for trend). AKI was associated with increased length of stay: median 6.0 days (IQR 4.0-8.75) versus 16.0 days (IQR 6.0-27.5), p<0.001. Multivariate analysis identified AKI and Child-Pugh classes B and C as independent factors associated with mortality.

CONCLUSIONS

The utility of AKIN criteria is maintained in cirrhotic patients. Decompensated liver disease and AKI appear to be independent variables predicting death in cirrhotics.

Mortality after urinary tract infections in patients with advanced cirrhosis - Relevance of acute kidney injury and comorbidities

BACKGROUND

Bacterial infections increase mortality four-fold in patients with decompensated cirrhosis. However, specific mortality associated with urinary tract infections (UTI) in cirrhosis is not known.

METHODS

Retrospective single-centre analysis of all hospitalized patients with cirrhosis and ascites who underwent first paracentesis between 2006 and 2011 to determine 90-day mortality associated with UTI defined as pyuria with significant bacteriuria using Cox proportional hazard models.

RESULTS

A total of 108 patients with at least one episode of UTI and 291 with exclusion of UTI were identified. Bacterial infections other than UTI were diagnosed in 136 (34%) of patients at the time of urine analysis. Female gender, Child-Pugh stage C, higher grade of ascites and systemic inflammatory response syndrome were associated with UTI. After adjustment for liver function and co-morbidity, the hazard ratios (HR) of death within 90 days after urine analysis were 2.08 (95% CI 1.28-3.38) in patients with UTI, 2.93 (1.90-4.52) in patients with other bacterial infections and 3.39 (2.03-5.65) in patients with UTI and concomitant infection. Independent predictors of death after UTI were renal dysfunction at presentation (HR 2.52; 95% CI 2.52), subsequent acute kidney injury within 48 h after diagnosis (4.57; 2.54-8.24), concomitant bacterial infection (1.77; 1.04-3.00) and malignant comorbidity (1.85; 1.03-3.30). The combination of these factors was more accurate in predicting 90-day mortality than the MELD score or C-reactive protein.

CONCLUSIONS

The presence of UTI indicates an increased risk of 90-day mortality in patients with advanced cirrhosis. Renal dysfunction and comorbidities are predictors of death in these patients.

Risk models and scoring systems for predicting the prognosis in critically ill cirrhotic patients with acute kidney injury: a prospective validation study

Background

Cirrhotic patients with acute kidney injury (AKI) admitted to intensive care units (ICUs) show extremely high mortality rates. We have proposed the MBRS scoring system, which can be used for assessing patients on the day of admission to the ICU; this new system involves determination of mean arterial pressure (MAP) and bilirubin level and assessment of respiratory failure and sepsis. We had used this scoring system to analyze the prognosis of ICU cirrhotic patients with AKI in 2008, and the current study was an external validation of this scoring system.

Methods

A total of 190 cirrhotic patients with AKI were admitted to the ICU between March 2008 and February 2011. We prospectively analyzed and recorded the data for 31 demographic parameters and some clinical characteristic variables on day 1 of admission to the ICU; these variables were considered as predictors of mortality.

Results

The overall in-hospital mortality rate was 73.2% (139/190), and the 6-month mortality rate was 83.2% (158/190). Hepatitis B viral infection (43%) was observed to be the cause of liver disease in most of the patients. Multiple logistic regression analysis indicated that the MBRS and Acute Physiology and Chronic Health Evaluation III (ACPACHE III) scores determined on the first day of admission to the ICU were independent predictors of in-hospital mortality in patients. In the analysis of the area under the receiver operating characteristic (AUROC) curves, the MBRS scores showed good discrimination (AUROC: 0.863±0.032, p<0.001) in predicting in-hospital mortality.

Conclusion

On the basis of the results of this external validation, we conclude that the MBRS scoring system is a reproducible, simple, easy-to-apply evaluation tool that can increase the prediction accuracy of short-term prognosis in critically ill cirrhotic patients with AKI.