Evaluation of terlipressin-related patient outcomes in hepatorenal syndrome-acute kidney injury using point-of-care echocardiography

BACKGROUND AND AIMS

Treatment of hepatorenal syndrome-acute kidney injury (HRS-AKI), with terlipressin and albumin, provides survival benefits, but may be associated with cardiopulmonary complications. We analyzed the predictors of terlipressin response and mortality using point-of-care echocardiography (POC-Echo) and cardiac and renal biomarkers.

APPROACH

Between December 2021 and January 2023, patients with HRS-AKI were assessed with POC-Echo and lung ultrasound within 6 hours of admission, at the time of starting terlipressin (48 h), and at 72 hours. Volume expansion was done with 20% albumin, followed by terlipressin infusion. Clinical data, POC-Echo data, and serum biomarkers were prospectively collected. Cirrhotic cardiomyopathy (CCM) was defined per 2020 criteria.

RESULTS

One hundred and forty patients were enrolled (84% men, 59% alcohol-associated disease, mean MELD-Na 25±SD 5.6). A median daily dose of infused terlipressin was 4.3 (interquartile range: 3.9-4.6) mg/day; mean duration 6.4 ± SD 1.9 days; the complete response was in 62% and partial response in 11%. Overall mortality was 14% and 16% at 30 and 90 days, respectively. Cutoffs for prediction of terlipressin nonresponse were cardiac variables [ratio of early mitral inflow velocity and mitral annular early diastolic tissue doppler velocity > 12.5 (indicating increased left filling pressures, C-statistic: 0.774), tissue doppler mitral velocity < 7 cm/s (indicating impaired relaxation; C-statistic: 0.791), > 20.5% reduction in cardiac index at 72 hours (C-statistic: 0.885); p < 0.001] and pretreatment biomarkers (CysC > 2.2 mg/l, C-statistic: 0.640 and N-terminal proBNP > 350 pg/mL, C-statistic: 0.655; p <0.050). About 6% of all patients with HRS-AKI and 26% of patients with CCM had pulmonary edema. The presence of CCM (adjusted HR 1.9; CI: 1.8-4.5, p = 0.009) and terlipressin nonresponse (adjusted HR 5.2; CI: 2.2-12.2, p <0.001) were predictors of mortality independent of age, sex, obesity, DM-2, etiology, and baseline creatinine.

CONCLUSIONS

CCM and reduction in cardiac index, reliably predict terlipressin nonresponse. CCM is independently associated with poor survival in HRS-AKI.

Value of shear wave elastography in predicting hepatorenal syndrome in patients with liver cirrhosis and ascites

BACKGROUND

Early detection of renal damage in cirrhosis is critical to prevent hepatorenal syndrome (HRS). Although shear wave elastography (SWE) is useful for the assessment of kidney stiffness, no study has yet investigated the clinical feasibility of SWE for predicting HRS.

OBJECTIVE

The aim of this study was to evaluate the value of SWE in predicting HRS in patients with cirrhosis and ascites.

METHODS

A total of 131 patients with liver cirrhosis and ascites were recruited and followed them for 30 days for the development of AKI. Ultrasonographic examination was performed on all patients at hospital admission. The baseline clinical characteristics, renal biomarkers, renal resistive index (RI) and Young's modulus (YM) were recorded, and their relationship with development HRS was investigated.

RESULTS

Sixty-eight patients developed AKI, 23 of them were HRS. Compared with patients in the non-AKI group and non-HRS group, the values of serum cystatin C (CystC), urine neutrophil gelatinase-associated lipocalin (NGAL) and renal RI were significantly increased, while the YM value was significantly decreased in the AKI group and HRS group. Correlation analysis showed that YM was significantly and negatively associated with serum creatinine, serum CystC, urinary NGAL and renal RI in addition to the significant association with the AKI stage. Logistic regression and ROC analysis showed that urine NGAL, renal RI and YM were closely related to the development of HRS. Among them, YM had a good predictive ability in predicting the occurrence of HRS, and the predictive value (AUC = 0.894) was improved when combined with renal RI.

CONCLUSION

SWE can indicate renal injury in patients with cirrhosis and ascites. The combination of YM and RI has a good predictive value for the occurrence of HRS.

Point-of-Care Echocardiography Unveils Misclassification of Acute Kidney Injury as Hepatorenal Syndrome

INTRODUCTION

Fulfillment of the diagnostic criteria for -hepatorenal syndrome type 1 (HRS-1) requires prior failure of 2 days of intravenous volume expansion and/or diuretic withdrawal. However, no parameter of volume status is used to guide the need for volume expansion in patients with suspected HRS-1. We hypothesized that point-of-care echocardiography (POCE) may better characterize the volume status in patients with acute kidney injury (AKI) and cirrhosis to ascertain or disprove the diagnosis of HRS-1.

METHODS

A pilot observational study was conducted to determine the clinical utility of POCE-based examination of inferior vena cava diameter (IVCD) and collapsibility index (IVCCI) to assess intravascular volume status in patients with cirrhosis and AKI who had been deemed adequately volume-repleted and thereby assigned a clinical diagnosis of HRS-1. Early improvement in kidney function was defined as ≥20% decrease in serum creatinine (sCr) at 48-72 h.

RESULTS

A total of 53 patients were included. The mean sCr at the time of volume assessment was 3.2 ± 1.5 mg/dL, and the mean Model for End-Stage Liver Disease score was 29 ± 8. Fifteen (23%) patients had an IVCD <1.3 cm and IVCCI >40% and were reclassified as fluid-depleted, 11 (21%) had an IVCD >2 cm and IVCCI <40% and were reclassified as fluid-expanded, and 8 (15%) had and IVCD <1.3 cm and IVCCI <40% and were reclassified as having intra-abdominal hypertension (IAH). Twelve (23%) patients exhibited early improvement in kidney function following a POCE-guided therapeutic maneuver, that is, volume expansion, diuresis, or paracentesis for those deemed fluid-depleted, fluid-expanded or having IAH, respectively.

CONCLUSION

POCE-based assessment of volume status in cirrhotic individuals with AKI reveals marked heterogeneity. Unguided volume expansion in these patients may lead to premature or delayed diagnosis of HRS-1.

Magnetic resonance elastography in the detection of hepatorenal syndrome in patients with cirrhosis and ascites

OBJECTIVE

Hepatorenal syndrome (HRS) is the most lethal cause of renal impairment in cirrhosis. Magnetic resonance elastography (MRE) is a diagnostic test that characterises tissues based on their biomechanical properties. The aim of this study was to assess the feasibility of MRE for detecting HRS in cirrhotic patients.

METHODS

A prospective diagnostic investigation was performed. Renal MRE was performed on 21 hospitalised patients with cirrhosis and ascites. Six patients had HRS, one patient had non-HRS renal impairment, and 14 patients had normal renal function. The MRE-measured renal stiffness was compared against the clinical diagnosis as determined by clinical review alongside laboratory and radiologic results.

RESULTS

The MRE-measured renal stiffness was significantly lower in patients with HRS (median stiffness of 3.30 kPa at 90 Hz and 2.62 kPa at 60 Hz) compared with patients with normal renal function (median stiffness of 5.08 kPa at 90 Hz and 3.41 kPa at 60 Hz) (P ≤ 0.014). For the detection of HRS, MRE had an area under the receiver operating characteristic curve of 0.94 at 90 Hz and 0.89 at 60 Hz. MRE had excellent inter-rater agreement, as assessed by Bland-Altman and intraclass correlation coefficient (> 0.9).

CONCLUSION

MRE shows potential in the detection of HRS.

KEY POINTS

• Magnetic resonance elastography (MRE) shows promise in the detection of hepatorenal syndrome. • MRE has the potential to track renal disease in a clinical population. • MRE is a reliable diagnostic test with excellent inter-rater agreement.

[Index resistance in renal ultrasound: what is the clinical significance?]

In the area of renal diagnosis, B-mode ultrasound allows for the study of renal morphology, while power color Doppler is of strategic importance not only for the qualitative and quantitative information it provides on renal vasculature, but also because it allows for the measurement of 'Index Resistance'. This is the ratio between the peak systolic speed [VPS] minus the telediastolic speed [VTD] and the VPS: [VPS-VTD/VTD]), now one of the most sensitive parameters in the study of renal pathologies through the quantification of changes in renal plasma flow. The reliability of the measurement of IR is dependent on accurate methodology, such as sampling at the level of the interlobar or arcuate arteries of 3 to 5 waves of similar dimensions in three different areas of the kidney, etc. Reliability also depends on careful analysis of the value obtained, owing to the confounding influence of peripheral resistance in addition to many other factors, including tachy-brady-arrhythmias, severe hypotension, and perirenal or subcapsular fluid collections. In adults an average IR of < 0.70 is considered normal, although this figure varies with age, giving higher values in children in the first years of life and in the elderly. The color Doppler measurement of IR at the level of the interlobar artery has been proposed as an indicator for differential diagnosis of acute or chronic nephropathies: for example, the ratio was higher in acute pathologies with vascular and tubulo-interstitial involvement, but not in those with glomerular involvement. This review aims to highlight clinical situations in which the study of intrarenal IR can provide useful information on the physiopathology of renal disease in both the native and in the transplanted kidney, as illustrated by the alterations of the morphology of the Doppler wave that are caused by variations in vascular resistance, hydrostatic capillary pressure and pressure inside the urinary tract.

Renal duplex Doppler ultrasound in patients with HCV related liver cirrhosis

AIM

To study the renal resistive index (RI) and pulsatility index (PI) measured by renal Doppler in various stages of liver cirrhosis and their values to detect cirrhotic patients at risk for developing the hepatorenal syndrome.

METHODS

This study included 60 cirrhotic patients divided into 4 groups (15 patients each): compensated liver cirrhosis (group A), diuretic responsive ascites (group B), refractory ascites (group C), hepatorenal syndrome (group D) and ten healthy persons as the control group (E). All patients were subjected to detailed history taking and clinical examination. Laboratory investigations included simple urine analysis, complete blood picture, liver function tests, blood urea and serum creatinine, serum sodium and serum potassium, 24-hour urine collection for sodium concentration, creatinine concentration and protein concentration. Ultrasonographic examination and renal duplex Doppler ultrasonography were undertaken to assess the RI and PI.

RESULTS

The RI of both interlobar and arcuate arteries was significantly higher in all patient groups than in the control group (p<0.01). The RI was significantly higher in patients with refractory ascites than in patients with diuretic responsive ascites, and also in patients with diuretic responsive ascites than in patients with compensated cirrhosis (p<0.01); in patients with hepatorenal syndrome than in patients with diuretic responsive ascites and patients with compensated cirrhosis (p<0.0001). The PI was significantly higher in all patients groups than in the control group (p<0.01) and in patients with refractory ascites than in patients with diuretic responsive ascites and was also higher in patients with responsive ascites than in patients with compensated cirrhosis (p<0.0001). Also, the PI was significantly higher in patients with hepatorenal syndrome than in patients with responsive ascites and patients with compensated cirrhosis (p<0.0001). Creatinine clearance in patients with the hepatorenal syndrome was significantly lower than that of other different groups (p<0.0001) but there was no significant change in creatinine clearance between patients with compensated cirrhosis and control group. While creatinine clearance in patients with diuretic responsive ascites was significantly higher than that in patients with compensated cirrhosis (p<0.05) there was no significant change between patients with diuretic responsive ascites and patients with refractory ascites.

CONCLUSION

Both renal resistive index and pulsatility index increase with the degree of hepatic decompensation. Renal duplex ultrasound which is a non-invasive, simple and easy method to study intrarenal hemodynamics in patients with liver cirrhosis may predict patients at risk of hepatorenal impairment.

The role of duplex-doppler ultrasonography in the diagnosis of renal dysfunction and hepatorenal syndrome in patients with liver cirrhosis

BACKGROUND/AIMS

Kidney dysfunction commonly develops in patients with liver cirrhosis. Renal failure develops due to renal vascular constriction and can be present weeks or even months before clinical signs or increased levels of blood urea nitrogen or serum creatinine concentrations become detectible. The objective of this study was to analyze the value of renal interlobar arterial resistance index, measured by duplex-Doppler ultrasonography for detecting early impairment of renal function in patients with liver cirrhosis and its possible use in detecting a subgroup of patients with a higher risk of developing hepatorenal syndrome.

METHODOLOGY

The patients were divided into three groups: patients with liver cirrhosis and normal renal function (n=31), patients with liver cirrhosis and renal failure but without hepatorenal syndrome criteria (n=9), and patients with hepatorenal syndrome (n=6). The interlobar arterial resistance index was estimated with duplex Doppler ultrasonography, and liver and renal function tests were measured in all patients.

RESULTS

The average value of interlobar arterial resistance index in patients with hepatorenal syndrome (0.74+/-0.01) was statistically significantly higher than interlobar arterial resistance index values measured in liver cirrhosis patients without the signs of azotemia (0.65+/-0.03) or in those with liver cirrhosis and kidney dysfunction, but without hepatorenal syndrome (0.67+/-0.01). In all patients with hepatorenal syndrome the value of interlobar arterial resistance index was over 0.70. In the group of patients with liver cirrhosis and kidney dysfunction, but without hepatorenal syndrome, interlobar arterial resistance index was below 0.70 in seven, whereas in the remaining two interlobar arterial resistance index was above 0.70. In those patients renal dysfunction displayed a progressive form and hepatorenal syndrome developed.

CONCLUSIONS

Duplex-Doppler ultrasound of intralobar arteries is a simple, effective and non-invasive method which enables the early detection of renal hemodynamic disturbances in patients with liver cirrhosis even before renal dysfunction becomes clinically evident. It also makes possible the identification of a subgroup of patients with liver cirrhosis who are at higher risks for developing hepatorenal syndrome.

Severe systemic reaction to (99m)Tc-methylene diphosphonate: a case report

We report an unusual severe systemic reaction that occurred in a woman after a (99m)Tc-methylene diphosphonate bone scan and for which no alternative explanation could be found. The bone scintigram showed diffusely increased uptake in the liver and kidneys accompanied by reversible dysfunction of these organs and dermatologic manifestations. We speculate that an immune-mediated mechanism may have caused this unusual reaction.

[Intrarenal arterial doppler ultrasonography in cirrhotic patients with ascites, with and without hepatorenal syndrome]

BACKGROUND

The pathophysiological hallmark of the hepatorenal syndrome (HRS) is renal vasoconstriction. Doppler ultrasonography can be used to assess the vascular resistance in small renal intraparenchymal vessels through analysis of the Doppler waveform by a parameter termed Resistive Index (RI). We postulated that the RI could be important for the diagnosis and prognosis of HRS.

AIMS

To assess the RI in cirrhotic patients with ascites, with and without HRS.

PATIENTS AND METHODS

We studied 48 cirrhotics with ascites, of whom 12 were with and 36 without HRS and other 23 were normal subjects. We measured the intrarenal arterial RI (Resistive index = Peak systolic velocity - Minimum diastolic velocity/Peak systolic velocity) with color Doppler ultrasonography after visualization of interlobular or arcuate arteries. It was considered abnormal when higher than 0.70.

RESULTS

The RI values, mean and SD) were: normal subjects: 0.58 +/- 0.05, cirrhotics with ascites: 0.65 +/- 0.05 and cirrhotics with ascites and HRS: 0.78 +/- 0.11. Patients with HRS had significantly higher values than those without HRS (p < 0.001). The Relative Risk of developing the HRS in patients with a RI > or = 0.70 were 3.32 (CI 95% = 1.79-6.2)

CONCLUSIONS

The RI was useful in patients with cirrhosis and ascites for the prognosis of HRS and could suggest diagnosis of HRS with values of 0.78 or higher, if other clinical conditions that produce renal vasoconstriction are excluded.

Microcomputed tomography of kidneys following chronic bile duct ligation

BACKGROUND

In hepatic cirrhosis, renal sodium and water retention can occur prior to decreases in renal blood flow (RBF). This may be explained in part by redistribution of the intrarenal microcirculation toward the juxtamedullary nephrons. To appreciate this three-dimensional spatial redistribution better, we examined the intrarenal microcirculatory changes using microcomputed tomography (micro-CT) in rats subjected to chronic bile duct ligation (CBDL).

METHODS

Six kidneys from control rats and eight kidneys from rats that had undergone CBDL for 21 days were perfusion fixed in situ at physiological pressure, perfused with silicon-based Microfil containing lead chromate, embedded in plastic, and scanned by micro-CT. The microvasculature in the reconstructed three-dimensional renal images was studied using computerized image-analysis techniques. To determine the physiological condition of the rats, parallel experiments were conducted on six control and six CBDL rats to measure mean arterial pressure (MAP), RBF, glomerular filtration rate (GFR), urine flow (UF) rate, and sodium excretion by conventional methods.

RESULTS

The percentage of vasculature in the renal cortex from CBDL rats was significantly decreased (10.8 +/- 0.4% vs. 16.8 +/- 2.7% control values). However, the vascular volume fractions of the medullary tissues were not significantly altered. There were no significant differences in the number of glomeruli between groups (36,430 +/- 1908 CBDLs, 36,609 +/- 3167 controls). The CBDL rats had a similar GFR than the controls but a reduced MAP, RBF, UF, and sodium excretion.

CONCLUSIONS

The results indicate that after CBDL, there is a selective decrease in cortical vascular filling, which may contribute to the salt and water retention that accompanies cirrhosis.

Renal blood flow detection with Doppler ultrasonography in patients with hepatic cirrhosis

BACKGROUND

Hepatorenal syndrome, a well-recognized complication of established liver disease, is characterized by early renal vasoconstriction before clinically recognized renal disease. Renal vasoconstriction causes increased renal vascular resistance, which can be detected noninvasively by Doppler ultrasonography.

OBJECTIVE

To detect early renal hemodynamic changes in patients with hepatic cirrhosis who had clinically normal renal functions.

PATIENTS

Twenty patients with hepatic cirrhosis and ascites, 11 patients with hepatic cirrhosis without ascites, and 23 healthy control subjects. All cirrhotic patients had normal serum urea nitrogen and creatinine values.

MAIN OUTCOME MEASURES

Peak systolic, peak diastolic, and mean flow velocities; pulsatile index; resistive index; and peak systolic velocity/peak diastolic velocity ratio as measured by renal Doppler ultrasonography.

RESULTS

Peak diastolic flow velocity was significantly lower in cirrhotic patients with ascites than in cirrhotic patients without ascites and control subjects (P < .02 and P < .004, respectively), but the peak systolic flow velocity/peak diastolic flow velocity ratio (P < .007 and P < .001, respectively), pulsatile index (P < .007 and P < .001, respectively), and resistive index (P < .007 and P < .001, respectively) were significantly higher in cirrhotic patients with ascites than in cirrhotic patients without ascites and controls.

CONCLUSION

Renal Doppler ultrasonography can noninvasively identify a subgroup of nonazotemic patients with hepatic cirrhosis who are at high risk for subsequent development of renal dysfunction and hepatorenal syndrome.

Plasma concentration of endothelin-1 does not reflect renal vasoconstriction as estimated by duplex ultrasonography in cirrhosis

Endothelin, a potent vasoconstrictor, is thought to play a role in liver cirrhosis-related functional kidney failure. Our aim was to investigate the correlation between renal vasoconstriction, as detected by a Doppler ultrasound technique, and plasma concentrations of endothelin in cirrhotic patients. Fifty cirrhotic patients underwent Doppler examinations to detect renal vasoconstriction. The plasma concentration of endothelin was measured in 10 patients who exhibited vasoconstriction of the renal microvessels diagnosed by Doppler waveform analysis and was compared to that of patients in whom there was no sign of such vasoconstriction. No difference was observed in the plasma concentration of endothelin between patients in whom renal vasoconstriction was diagnosed and those in whom it was not. Our results suggested that the circulating endothelin does not reflect renal vasoconstriction, at least in the early phase of the functional renal failure associated with cirrhosis of the liver.

Abnormal renovascular impedance in patients with hepatic cirrhosis: detection with duplex US

The purpose of this study was to determine whether duplex ultrasound (US) can allow detection of early impairment of renal function in patients with hepatic cirrhosis. The authors calculated the pulsatility index (PI) and resistive index (RI) by using duplex US in 17 patients with cirrhosis and ascites but with normal renal function (group A), in 16 patients with cirrhosis but no ascites (group B), in 20 with chronic hepatitis (group C), in six with peritoneal carcinomatosis (group D), and in 16 healthy control subjects (group E). All patients had normal renal function on the basis of blood urea nitrogen and serum creatinine values. PI and RI were higher (P < .001) in group A patients than in others. Cirrhotic patients with ascites had renal vasoconstriction even in the absence of clinically apparent renal impairment and full-blown hepatorenal syndrome. Impaired renal perfusion plays a key role in sodium and fluid accumulation in patients with liver disease. On the basis of these results, duplex US is useful in pathophysiologic and clinical studies in such patients.

Tc-99m DTPA and I-131 hippurate renography. Findings in hepatorenal syndrome

Tc-99m DTPA and I-131 OIH renography were performed simultaneously in a patient with hepatorenal syndrome. Blood flow was delayed and diminished bilaterally; there was Tc-99m DTPA and I-131 OIH retention in the parenchyma with no evidence of tracer retention in the collecting systems. The I-131 OIH renogram curve demonstrated a steadily rising pattern, whereas the Tc-99m DTPA curve demonstrated an initial vascular peak and was subsequently flat. There was no appreciable response to furosemide. These findings are not specific for hepatorenal syndrome, and the diagnosis is based on the characteristic clinical setting and the exclusion of other causes of renal failure. A brief literature review and a discussion of differential diagnosis are included.