1. Ultrasuoni versus Breath Test: Pro e Contro nella valutazione del danno epatico 13 C-Breath Tests in epatologia Edoardo G. Giannini Cattedra di Gastroenterologia, Dipartimento di Medicina Interna, Università di Genova. Corso SIGE: “Test Non-Invasivi” – Roma, 19 giugno 2015

2. Agenda - What is liver function? - Why should we assess liver function? - Use of BTs to assess liver function(s) - Conclusions 13 C-Breath Tests in chronic liver disease

3. Quantitation of Intrinsic Drug-Metabolizing Capacity: The Intact-Hepatocyte Theory “…the changes within the liver can be considered to be due to reduced mass of cells which function relatively normally and are normally perfused.” What is liver function? Branch RA. Hepatology 1982; 2: 97-105.

4. Two reasons for decreased hepatic function in chronic liver disease: What is liver function? 1. Alteration of blood flow 2. Impairment of the intrinsic metabolic activity Decreased hepatocellular functioning mass

5. -The “liver biopsy paradigm” -The complexity of liver functions and the derangement of hepatic physiology in liver disease -To score or to measure: that’s the question! -Patients prognosis alias going beyond fibrosis Why should we assess liver function?

6. Can 13 C-Breath Tests be considered surrogate markers of liver fibrosis? The complexity of liver functions… Is liver fibrosis a surrogate marker for liver function?

7. Histological Clinical Instrumental Assessing disease stage and liver function

8. F1F2F3F4 “…grading and staging…are not measurements…A grade of 2 for a particular feature…is not exactly half way between 1 and 3; it is merely in the opinion of the pathologist…more than 1 and less than 3. It follows that the number generated must not be manipulated as if they were exact measurements” P. Scheuer ?????? Liver function The “liver biopsy paradigm”

9. To score or to measure: that’s the question! 5-6 7-9 10-15 Child-Pugh score 0 0 1 1 2 2 3 3 4 4 METAVIR fibrosis score MELD score Equal transition between stages Variables weight Variables subjectivity/’manipulation’ Assay variability (INR) Not comprehensive of CLD spectrum

10. Patients prognosis alias going beyond fibrosis

11. Liver BTs: Principles Chronic Liver Disease Distortion of vascular architecture Shunting of hepatic blood flow Decreased hepatocellular functioning mass Giannini EG, et al. Eur Rev Med Pharmacol Sci 2004; 8: 51-4. Inflammation Necrosis FibrosisRegeneration Disease stage and patients prognosis

12. Liver BTs: Principles Time 13 CO 2 total amount Normal Cirrhosis 13 C-Substrate Metabolite 13 CO 2 Rate-limiting step Discrete versus Continuous

13. Liver BTs: Principles AminopyrineMicrosomalP450s MethacetinMicrosomalCYP1A2 Probe Hepatic function Enzyme studied GalactoseCytosolicGalactokinase PhenylalanineCytosolicHydroxylase  -Ketoisocaproic acidMitochondrial  ketoacid dehydrogenase complex Blood flow dependent: 13 C-MBT 13 C-GBT Blood flow independent: 13 C-ABT 13 C-GBT 13 C-PBT 13 C-KICABT Armuzzi A, et al. Aliment Pharmacol Ther 2002; 16: 1977-96.

14. Liver BTs: Principles Branch RA. Hepatology 1982; 2: 97-105.

15. Liver BTs: Results interpretation Giannini E, et al. Aliment Pharmacol Ther 2002; 16: 717-25. ABT % cum/hr Peak Shape AUC

16. Am I sick? 1. To detect disease How bad is my disease? 2. To assess disease severity How long will I live? 4 4. To establish prognosis Will this drug be good for me? 3 3. To evaluate the effects of treatment Why should we assess liver function?

17. 1. To detect disease Giannini E, et al. Aliment Pharmacol Ther 2002; 16: 717-25. P=0.001 13 C-Aminopyrine BTHCV patients

18. 1. To detect disease Lalazar G, et al. J Viral Hep 2008; 15: 716-28. 13 C-Methacetin BT HCV patients PNAL Continuous breath sampling device Fibrosis score>2 AUROC=0.915

19. 1. To detect disease Portincasa P, et al. Clin Sci 2006; III: 135-43. 13 C-Ketoisocaproic acid BT NASH patients

20. 2. To stage disease Mion F, et al. Eur J Clin Invest 1999; 29: 624-9. 13 C-Aminopyrine BTHCV patients

21. Giannini EG, et al. Clin Gastroenterol Hepatol 2005; 3: 279-85. 2. To stage disease p<0.001 13 C-Galactose BTMixed aetiology

22. 2. To stage disease Forestier J, et al. Eur J Gastroenterol Hepatol 2010; 22: 532-40. AUC (95% CI) - Fibroscan 0.93 (0.90-0.96) - 13 C-ABT 0.82 (0.77-0.87) - APRI 0.81 (0.76-0.86) Cirrhosis P<0.0001

23. 3. To evaluate the effect of treatment Ocker M, et al. World J Gastroenterol 2005; 11: 5521-4. 13 C-Aminopyrine BT Chronic HCV infection on IFN P<0.05 Week 12

24. 13 C-Aminopyrine BT Chronic, untreated HCV infection Rocco A, et al. J Hepatol 2012; 56: 782-7. 4. To establish prognosis Basal fibrosis stage 2.7±0.8 (NP) versus 3.1±0.9 (Progr.)

25. 4. To establish prognosis Giannini EG, et al. Dig Dis Sci 2013; 58: 3024-8. 13 C-Aminopyrine BT: 1-year survival in cirrhosis 13 C-ABT %dose/h 30 -MELD score: r= -0.414; P=0.004 13 C-ABT %dose/h 30  2.0 13 C-ABT %dose/h 30 >2.0 P=0.001 (days)

26. 4. To establish prognosis Degré D, et al. Transpl Int 2004; 17: 31-8. AUROC: ABT0.858 CTP score0.726 MELD0.704 13 C-Aminopyrine BT Mixed aetiology (42% ETOH) 90-day survival on OLT wating list P=0.07 P=0.02

27. 4. To establish prognosis OLT and MELD Ecohard Y, et al. Clin Transplant 2011; 25: 755-65. 13 C-Aminopyrine BT Dose/hr >2% Dose/hr 1-2% Dose/hr <1% 90-day survival = 78% 90-day survival = 51%

28. Why should we use liver BTs? Afolabi P, et al. Dig Dis Sci 2013; 58: 33-41. Clinical assessment using 13 C Breath Tests in patients with liver disease Diagnostic utilityPrognostic utility Monitoring liver function Recognition/exclusion of liver disease in a target population Prediction at an early stage of the severity and possible outcome of disease Determining the course of disease and the impact of clinical management on patients outcome -Various substrates with ≠ accuracy -Better accuracy in advanced stages -/+ ++ -Possible use alone -Helpful in fine-tuning prognosis in association with other scores +/- ++ -Serial determinations (prognosis; therapeutic outcome) +++

29. Limitations -Dedicated equipment, experienced physicians -Factors affecting results variability (CYP polymorphisms; gender, age; co-medications; comorbid illnesses) -Competing techniques (elastography, ARFI, etc.) -Costs

30. Conclusions - 13 C-Liver Breath Tests can provide useful information that goes beyond simple evaluation of fibrosis -BTs can be used to detect disease, stage its severity, and foresee patients’ prognosis -They should not substitute the common tools used in the clinical work-up of the patients but their use may be complementary

31. Jean Siméon Chardin (1699-1779) ) La bulle de savon (1734)