0 Hepato-renal Syndrome – What is it? Akash Deep, Director - PICU King’s College Hospital London

Questions to be answered How common is renal dysfunction in children with liver disease ? Is every renal dysfunction in liver disease Hepatorenal Syndrome (HRS) ? What is the impact of kidney dysfunction in children with existing liver disease? – Prognosis What is HRS – Definition, pathogenesis, diagnosis Impact of HRS on transplant candidacy? 1

Hepatorenal Syndrome No data exists in paediatric literature Adult data extrapolated. 2

Progress of cirrhosis 3

Braveno IV status classification of cirrhosis STAGE 1. NO VARICES NO ASCITES STAGE 2. VARICES NO ASCITES STAGE 3. ASCITES VARICES STAGE 4. BLEEDING +/- ASCITES 1-year Outcome Probabilities DEATH 1% 3.4% 20 % 57% J Hepatology 2006;44:

Natural History Chronic Liver Disease J Hepatology 2006;44: Christensen et al Scand J Gastro 1989;24:

Mortality Prediction Scores in Cirrhosis Extra-hepatic organ dysfunction progresses Common ITU Scores – PIM2, Child Pugh Score, MELD, SOFA, APACHE Renal Dysfunction omitted or only based on SCr How important is the contribution of renal dysfunction to the mortality of patients with liver disease? Inclusion of SCr in Model for End- Stage Liver Disease (MELD) 7

AKI in Liver disease Is every AKI in liver disease HRS ? What are the different causes of AKI in liver disease? Can we reliably differentiate between the various causes of AKI? If HRS exists, what is it, clinical manifestations and diagnosis and how do we treat it? Impact of AKI on transplant candidacy? 9

Frequent causes of AKI in CLD Pre-renal : Hypovolaemia: GI bleeding – (don’t forget the ulcer ) GI fluid losses (Lactulose, Terlipressin, PPI) Diuretics abuse/over use Acute Tubular necrosis Parenchymal disease: GN, Cryoglobulinaemia, IgA nephropathy – Biopsy? ATN/HRS Drugs: CIN, NSAIDS, Abx, CNI post Tx Intra Abdominal Hypertension Hepato-renal Syndrome

Kidney dysfunction in cirrhosis Natural Progression of disease complications Renal dysfunction HRS V/s Stable patient with cirrhosis, PHT precipitating event HRS 11

HRS, does it exist?

Epidemiology 50% of patients with cirrhosis with ascites will develop AKI HRS constitutes a very small proportion of AKI in cirrhosis ONLY 7.6% of all 129 cirrhotics with AKI had HRS as the cause of deterioration ( Montoliu S, Ballesté B, Planas R, et al ) Multicentre trial – 423 patients with cirrhosis and AKI (ATN -35%, Pre-renal failure-32%, HRS-1- 20%, HRS % (Moreau R, Durand F, Poynard T, et al)

Adult vs Paediatric HRS Biliary atresia most common cause of OLT Fewer numbers and split liver transplant Waiting lists smaller – transplant – no HRS Adults – more in number, varied aetiologies, longer waiting lists and develop all complications including HRS HRS in Paediatrics VERY RARE. 14

What is HRS ? Hepatorenal syndrome (HRS) is defined as the occurrence of renal failure in a patient with advanced liver disease in the absence of an identifiable cause of renal failure DIAGNOSIS OF EXCLUSION 15

Issues : Not even eGFR Creatinine is produced in the liver Woman vs men Ethnic diversity Decreased muscle mass in cirrhosis Consider acute renal dysfunction in cirrhosis : RIFLE

Problems with Serum Creatinine Bilirubin interferes with assays, with hyperbilirubinaemia masking increase in SCr Ethnic and Sex predilection Liver synthetic function -production of creatinine is reduced by 50% Muscle mass and protein malnutrition Lower baseline range for creatinine in advanced liver disease Cirrhotic patients for a given change in GFR have smaller and delayed changes in SCr Delay access to timely HRS treatment and may adversely affect these patients’ prognosis. 17

Characteristics of Type 1 and Type 2 Hepatorenal Syndrome CoursePrecipitati ng Event History of Diuretic- Resistant Ascites Prognosis Type -1 HRS Acute, MOF, Precipitous doubling of serum creatinine in < 2 weeks Present in > 50% of cases, overlaps with other causes of AKI May or may not be present Without therapy- 90-day survival of 10% Type -2 HRS Gradually progressive AbsentAlways Present Median survival- 6 months

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Mediators of Splanchnic Vasodilatation Nitric Oxide (shear-stress-induced upregulation of endothelial NO synthase (eNOS) activity and endotoxin-mediated eNOS) Calcitonin gene-related peptide (CGRP) Substance P Carbon monoxide Endocannabinoids Overproduction of TNF-α may be a major mechanism leading to HRS 21

Pathophysiology of CLD Peripheral and splanchnic arterial dilatation Reduced effective blood volume Activation of renin-angiotensin-aldosterone system Sympathetic nervous system ADH Na retention & Water retention Low urinary Na Dilutional hyponatraemia Ascites Schrier et al Hepatol 1988 Plasma volume expansion Renal vasoconstriction Reduced GFR NSAID Aminoglycosides Diuretics Sepsis NaCl Ascites and Oedema HRS Portal Hypertension

TNF IL6 NO Bacterial DNA LPS binding protein Norfloxacin effect Effects of SBP

Gut 2008

Intra-abdominal pressure Sugrue et al Arch Surg :1082 Malbrain CCM 2005;33: patients 40.7% increased IAP Renal dysfunction: 32% with IAP elevated 14% with normal IAP 32% IAP > 12 40% IAP > 20 CVP PcwP Compliance  IAP

Renal autoregulation in HRS 28

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Renal Blood Flow in cirrhotics Ring-Larsen et al. Splannchnic vasodilation Decreased ITBV Intra-hepatic resistance Porto-renal reflex

Precipitating Factors Lead to rapid deterioration of the systemic circulation and to the development of the HRS Gastrointestinal bleedingGastrointestinal bleeding Spontaneous bacterial peritonitisSpontaneous bacterial peritonitis SepsisSepsis Aggressive diuresisAggressive diuresis Large volume ParacentesisLarge volume Paracentesis CholestasisCholestasis NSAIDsNSAIDs

ATN AKI What is what?

HRS - Diagnosis of exclusion Hepatorenal syndrome (HRS) is defined as the occurrence of renal failure in a patient with advanced liver disease in the absence of an identifiable cause of renal failure The diagnosis of HRS is one of exclusion, so investigations should be performed to rule out other common causes of AKI. 34

Differentiating one from the other HRS and ATN difficult to differentiate Granular casts observed in the urinary sediment in both conditions Presence of renal tubular epithelial cells favours ATN FeNa < 1.0% - tubular reabsorptive integrity favours HRS Hpovolemic or septic shock immediately before renal failure - ATN Prolonged HRS ATN ???? 35

Prognosis Depends on etiology HRS carries the worst survival among all causes of AKI in cirrhotic patients 562 cirrhotic patients with AKI 3-month survival : HRS patients -15% Infection induced AKI - 31% Hypovolemia-induced AKI -46% AKI associated with evidence of parenchymal renal disease - 73% Determining the etiology of AKI in cirrhotic patients does not only determine the treatment plan but also foretells the prognosis. 36

Creatinine >1.5 mg/dl 463 patients over 6 years Single centre 3 month mortality

Implications of AKI on transplantation Patients with cirrhosis and renal failure are at high risk for death while awaiting transplantation HRS is a strong predictor of mortality In patients listed for transplantation, the development of HRS – Untransplantable or who receive a transplant associated with increased morbidity and mortality after transplantation 38

Why is HRS considered functional? Initially histological abnormalities are minimal and inconsistent Tubular function and sodium absorption remains intact Kidneys transplanted from patients with HRS can resume normal function in the recipient Renal function can return in patients with HRS who receive liver transplant Only 2/3rds recover kidney function after transplantation. 39

Prognosis 50% at 2, 20% at 6 months 1 vs 6 months respectively

Prognosis of HRS -1 and 2 Gines et al – 134 HRS patients o 2-week mortality rate 80% in untreated type 1 HRS patients with only 10% of patients surviving for 3 months Salerno et al HRS patients o Some of them did receive vasoconstrictor therapy o 3-month survival was 20% and 40% for type 1 and type 2 HRS, respectively.

Conclusion AKI common in decompensated cirrhotics Not every AKI in cirrhosis is HRS Extremely rare in paediatrics AKI predicts increased mortality in liver disease HRS drastic complication and carries a very bad prognosis Splanchnic vasodilatation and renal vasoconstriction – main causes Need to know what caused AKI – is it HRS ???? 42