Novel Technologies for Organ Assessment

• Assessment of liver function

Vanessa Banz, MD, PhD

Daniel Candinas, MD

2

Relevance of assessing liver function

•Prognostic context in acute and end

stage liver disease

•Adjusting pharmakodynamics

•Prevention of liver failure after partial

liver resection

•Assessing donor liver function (life and

cadaveric)

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4

Synthesis

Vasoregulation

Detoxification

Immune control

Metabolism

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Some Metabolic functions

• Glucose and Fatty Acids

• Lipoprotein

• Plasma Protein

• Vitamin Metabolism (A & D)

• Xenobiotics

• Bilirubin

• Receptor Mediatied Endocytosis and Metabolism

• Iron & Copper Metabolism

• Amino Acid Metabolism

• Etc..

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The liver as a vasoregulatory organ

Casting of the mouse liver vasculature by D. Sidler, D. Inderbitzin & V. Djonov, D. Candinas

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Full liver function depends on the integrity of all

cellular compartments (e.g. biliary microcirculation)

Haratake et al; Hepatology

1991;14(6):1196-200.

Hepatic artery

thrombosis after

OLT

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The liver as an immune organ

• Infection and Sepsis are dominant causes of death in liver

failure

– Chronic liver failure

– Acute liver failure

– Small for size syndrome

– Post transplant

How to measure immune function?

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Breaching Barriers.

Franz J. Zemp et al., Sci Transl Med 2014;6:237fs22

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Liver firewall function is compromised in liver disease independently of alterations in innate

immunity.

Maria L. Balmer et al., Sci Transl Med 2014;6:237ra66

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Fig. 4. Disturbance of host-microbial mutualism in human patients with liver dysfunction.

Maria L. Balmer et al., Sci Transl Med 2014;6:237ra66

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Immune functions (numerous interactions)

Hepatology. 2014 Dec;60(6):2109-17. doi:

10.1002/hep.27254.

Immune tolerance in liver disease

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And the hepatocyte as the agent

J Immunol. 2016 Jan 1;196(1):17-21. doi:

10.4049/jimmunol.1501668.

Hepatocytes as Immunological Agents.

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there is no liver function test available that

measures all components of liver function

Restricted information on functionality

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Functions tests – a choice

• Passive Liver function tests

– Bilirubin

– Albumin and Coagulation factor synthesis

• Clinical grading systems

– Child Pugh Score

– MELD Score

• Dynamik Quantitaty tests

– Indocyanine Greeen Clearance Test

– Galaktose Capacity Test

• Mulecular nuclear imaging techniques

– 99mTc-Galactosyl Serum Albumin Scintigraphy

– 99mTc-Mebrofenin Hepatobiliary Scintigraphy

• From morphology to function

– Imaging assessment

– Stiffness

– Histology

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Passive tests: Bilirubin

• plasma concentration -> indirect information on uptake, conjugation,

excretion of the liver

• any liver pathology that affects organic anion transporting polypeptide

expression automatically alters bilirubin kinetics

e.g. cytokines released by Kupffer cells

skew bilirubin-related test outcomes

• influenced by nonhepatic factors

plasma bilirubin concentration is not a parameter of

liver function per se in these instances

Hoekstra, Annals of Surgery 2013

Tanaka, Transplantation 2006

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Passive tests: Albumin & Clotting Factors

• Factor V, XIII, fibrinogen, antithrombin, α2-plasmin inhibitor,

and plasminogenare exclusively synthesized by the liver

• Plasma concentrations are indirect indicators of liver

synthesis function Hoekstra, Annals of Surgery 2013

Clichy-Villejuif (CV) criteria in France (Factor V & Encephalopathy) J. Bernuau et al: Hepatology 1991

“The performance of current criteria for SU transplantation could be improved if

paracetamol-induced ALF and non–paracetamol-induced ALF were split and 2

other items were included in this model: the bilirubin level and creatinine

clearance. “ Cherqui et al: Liver Transpl 21:512-523, 2015

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Arterial pH < 7.3 or

Prothrombin time > 100 s

Grad III Encephalopathy

Creatinin > 300 µmol/L

Age < 30 yrs & Factor V < 20%

Age >30 yr & Factor V < 30%

Scoring Systems in Acute liver failure

Time to recovery ?

Underlying disease

Preserved function

Cerebral oedema

Metabolic failure

Multiorgan failure

Complications Regeneration

Kings criteria

Clichy-Villejuif criteria

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Scoring Systems in Chronic liver failure

• Bleeding

• Jaundice

• Malnutrition

• Ascites

• Oedema

• Pruritus

• Encephalopathy

• Malignoma

Synthetic failure and

portal hypertension

Child Pugh

MELD

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Dynamic tests: Indocyanine Green Clearance Test

• Tricarbocyanine dye that binds to albumin & lipoproteins

• Distributes uniformely after injection within 3 min

• Exclusively cleared by hepatocytes and excreted into bile

• Elimination depends on: blood flow, cellular uptake, biliary

extrection

–Plasma disappearance rate

(PDR) normal ranges:16% and 25% per minute

– Indocyanine green elimination

rate constant (indocyanine green-k)

– Indocyanine green-R15

(% clearance at 15 min)

Paumgartner G. Schweiz Med Wochenschr. 1975

Faybik P. Transplant Proc. 2006

Sakka SG. Assessing liver function. Curr Opin Crit Care. 2007

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IGC Validation

• Several studies report moderate-high correlation with

outcome after surgery, liver resection, transplantation

• Conversly ICG may be misrepresentativ:

– strongly dependent on hepatic blood flow alterations,

inhomogenous structural changes

– reduced transport capacity

Caveat in:

–cholostatic patients

– Hemodynamically instable patients

Limited value Hoekstra, Annals of Surgery 2013

Inderbitzin D: J Gastrointest Surg. 2005

Lam CM: Br J Surg. 1999

Watanabe Y: J Cardiothorac Vasc Anesth 1999

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Dynamic tests: Galactose Elimination Capacity Test

• Determines the metabolic capacity

• Galactose is phosphorylated intracellularly to galactose-1-

phosphate by galactokinase. Galactose-1-phosphate is

then converted to glucose-1-phosphate by the action of 4

enzymes

• GEC is calculated from serial serum samples 20 - 50 min

postinjection

Goresky CA: J Clin Invest. 1973

Holden HM: J Biol Chem. 2003

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GEC Validation

• prognostic significance in

–chronic liver disease

– fulminant hepatic failure

• Abnormal clearance in patients with liver metastasis

• Alterations in liver metabolims affect predictive value

–Environmental changes

–Hypoxia (HRE Sites in key enzyme) D. Stroka, personal communiction

– Increased membrane synthesis during liver regeneration

–Altered galactose kinetics during regeneration and fasting

–Only global function measured (no anatomical correlate)

Herold C: Liver. 2001

Redaelli CA: Ann Surg. 2002

Reichen J: Hepatology. 1991

Hoekstra, Annals of Surgery 2013

+/- robust test, time consuming

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Molecular imaging techniques: 99mTc-Galactosyl

Serum Albumin Scintigraphy

• 99mTc-diethylenetriamine-pentaacetic acid-galactosyl human serum

albumin = analogue ligand of asialoglycoprotein binding to

asialoglycoprotein receptors on

the hepatocyte cell membrane

• Receptors are expressed only

on the hepatocyte sinusoidal

surface facing the space of

• Uptake via receptor-mediated

endocytosis.

• The liver is the only uptake site

Hoekstra L: Annals of Surgery. 257(1):27-36, January 2013. Digital Object Identifier: 10.1097/SLA.0b013e31825d5d47

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Validation: 99mTc-Galactosyl Serum Albumin Scintigraphy

• Test has proven valuable in cirrhotic patients

• Demonstrated a good relationship with conventional liver

function tests and histology

• Is not influenced by hyperbilirubinemia (not binding)

• No biliary excretion

• Not suitable for the evaluation of biliary obstruction

Hoekstra L: Annals of Surgery. 257(1):27-36, January 2013

Takeuchi: Hepatogastroenterology. 1999

Satoh K: Ann Nucl Med. 2003

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From morphology to function

• Tests based on stiffness assessment

–Fibroscan

–MRI based

• Histology / Macroscopy (Laparoscopy)

• Volumetry

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Liver stiffness correlates with ICG Clearance Acoustic radiation force impulse (ARFI) imaging in patients with liver tumors

Sun XL: World J Gastroenterolog 2015

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Liver stiffness with different degrees of fibrosis measured using

magnetic resonance elastography

In correlation with indocyanine green retention rate at

15 min and indocyanine green plasma clearance rate

A-C: LS, 2.9 kPa; ICGR-15, 0.003; ICG-K, 0.398

D-F: LS, 4.4 kPa; ICGR-15, 0.057; ICG-K, 0.191

G-I: LS, 5.1 kPa; ICGR-15, 0.083; ICG-K, 0.166

J-L: LS, 10 kPa; ICGR-15, 0.252; ICG-K, 0.092

ICGR-15: Indocyanine green retention rate at 15 min;

ICG-K: Indocyanine green plasma clearance rate; LS: Liver

stiffness.

Native Stiffness ICGR-15

Bin L: World J Gastroenterol 2015

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Computer based Volumetry with risk analysis

Examples of Clinical Cases University Hospital Bern

calculated with MEVIS System

MEVIS Medical Solutions AG, Bremen, Germany

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Clinical scenarios

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Highlight: Small for Size Syndromes

• High flow small volume SFS syndrome.

• Poor function small volume small for size syndrome

Standard liver Volume ca. 25- 30%

Correction: Steatosis - Drug damage, Fibrosis, Resection margins

Portal Perfusion – venous Obstruction – biliary

obstruction – arterial flow

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Assessing Chemotherapy associated liver damage

SOS (sinusoidal obstructive Syndrome)

In a clinical Case

post Neoaduvant Chemotherapy

University Hospital Bern

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day 0 day 7

Seg II/III 720ml 950ml

Patient M 69 J – 105 kg – post Chemo with SOS Syndrom

Pictures courtesy to PD Martin Maurer, Radiologie Inselspital

ASSOCIATING LIVER PARTITION WITH PORTAL VEIN LIGATION FOR

STAGED HEPATECTOMY (ALPPS )

Plus 31%

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‘Marginal’ liver donor

One or more of the following:

–Adverse history • Alcohol abuse, Drug overdose, Severe cardiovascular disease

–severely deranged LFTs –severe steatosis – lengthy hypotension –high-dose inotropes –prolonged ITU stay –sepsis

Mirza D, Lancet 1994

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Steatosis of the liver and transplantation

• Macroscopic greasy, yellow

• Microscopic

macro- microvesicular

Mild <30% save save

Moderate 30-60% IPF ok

Severe >60% PNF ! IPF

Adapted from D’Alessandro 1991

Fishbein 1997 and Barbier 2016

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Preservation injury and severe steatosis

deterioration in

mitochondrial function

Decreased plasma

membrane fluidity

ATP depletion Bleb formation Sinusoidal lining

cell injury

Sinusoidal microcirculatory disorder

Poor graft function

Fukomori, Tranplantation 1999

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Conclusions

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0

10

20

30

40

50

60

26% 60% 75%

% liver resected

% B

rdU

po

sitiv

e c

ells

We know: The liver regenerates !

60%

75%

26%

Inderbitzin D, Studer P, Candinas D: Personal communication

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0

10

20

30

40

50

60

26% 60% 75% 83%

% liver resected

% B

rdU

po

sitiv

e c

ells

... but not always!

60%

75%

26%

83% Inderbitzin D, Studer P, Candinas D: Personal communication

Pushing the margin of safety

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In clinical pratice

• A «sound» combination of more than one liver function test

is needed

• In critical cases protocols for dynamic tests should be

established and working in institutions

• In doubt surgeons use either minimally invasive methods

(e.g. ablations and local resections) rather than large

anatomical resections

• In doubt for small for size syndrome surgeons favour

staged procedures and protocols that induce hypertrophy

• Nothing replaces a interdisciplinary evaluation of patients

at risk