F. Ravaioli

Gut Microbiota and Celiac Disease

Recent evidence regarding celiac disease has increasingly shown the role of innate immunity in triggering the immune response by stimulating the adaptive immune response and by mucosal damage. The interaction between the gut microbiota and the mucosal wall is mediated by the same receptors which can activate innate immunity. Thus, changes in gut microbiota may lead to activation of this inflammatory pathway. This paper is a review of the current knowledge regarding the relationship between celiac disease and gut microbiota. In fact, patients with celiac disease have a reduction in beneficial species and an increase in those potentially pathogenic as compared to healthy subjects. This dysbiosis is reduced, but might still remain, after a gluten-free diet. Thus, gut microbiota could play a significant role in the pathogenesis of celiac disease, as described by studies which link dysbiosis with the inflammatory milieu in celiac patients. The use of probiotics seems to reduce the inflammatory response and restore a normal proportion of beneficial bacteria in the gastrointestinal tract. Additional evidence is needed in order to better understand the role of gut microbiota in the pathogenesis of celiac disease, and the clinical impact and therapeutic use of probiotics in this setting.

Differences in liver stiffness values obtained with new ultrasound elastography machines and Fibroscan: A comparative study

BACKGROUND AND AIMS Whether Fibroscan thresholds can be immediately adopted for none, some or all other shear wave elastography techniques has not been tested. The aim of the present study was to test the concordance of the findings obtained from 7 of the most recent ultrasound elastography machines with respect to Fibroscan. METHODS Sixteen hepatitis C virus-related patients with fibrosis ≥2 and having reliable results at Fibroscan were investigated in two intercostal spaces using 7 different elastography machines. Coefficients of both precision (an index of data dispersion) and accuracy (an index of bias correction factors expressing different magnitudes of changes in comparison to the reference) were calculated. RESULTS Median stiffness values differed among the different machines as did coefficients of both precision (range 0.54-0.72) and accuracy (range 0.28-0.87). When the average of the measurements of two intercostal spaces was considered, coefficients of precision significantly increased with all machines (range 0.72-0.90) whereas of accuracy improved more scatteredly and by a smaller degree (range 0.40-0.99). CONCLUSIONS The present results showed only moderate concordance of the majority of elastography machines with the Fibroscan results, preventing the possibility of the immediate universal adoption of Fibroscan thresholds for defining liver fibrosis staging for all new machines.

A combined model based on spleen stiffness measurement and Baveno VI criteria to rule out high-risk varices in advanced chronic liver disease

BACKGROUND & AIMS Recently, Baveno VI guidelines suggested that esophagogastroduodenoscopy (EGD) can be avoided in patients with compensated advanced chronic liver disease (cACLD) who have a liver stiffness measurement (LSM) <20 kPa and platelet count >150,000/mm3. We aimed to: assess the performance of spleen stiffness measurement (SSM) in ruling out patients with high-risk varices (HRV); validate Baveno VI criteria in a large population and assess how the sequential use of Baveno VI criteria and SSM could safely avoid the need for endoscopy. METHODS We retrospectively analyzed 498 patients with cACLD who had undergone LSM/SSM by transient elastography (TE) (FibroScan®), platelet count and EGDs from 2012 to 2016 referred to our tertiary centre. The new combined model was validated internally by a split-validation method, and externally in a prospective multicentre cohort of 115 patients. RESULTS SSM, LSM, platelet count and Child-Pugh-B were independent predictors of HRV. Applying the newly identified SSM cut-off (≤46 kPa) or Baveno VI criteria, 35.8% and 21.7% of patients in the internal validation cohort could have avoided EGD, with only 2% of HRVs being missed with either model. The combination of SSM with Baveno VI criteria would have avoided an additional 22.5% of EGDs, reaching a final value of 43.8% spared EGDs, with <5% missed HRVs. Results were confirmed in the prospective external validation cohort, as the combined Baveno VI/SSM ≤46 model would have safely spared (0 HRV missed) 37.4% of EGDs, compared to 16.5% when using the Baveno VI criteria alone. CONCLUSIONS A non-invasive prediction model combining SSM with Baveno VI criteria may be useful to rule out HRV and could make it possible to avoid a significantly larger number of unnecessary EGDs compared to Baveno VI criteria only. LAY SUMMARY Spleen stiffness measurement assessed by transient elastography, the most widely used elastography technique, is a non-invasive technique that can help the physician to better stratify the degree of portal hypertension and the risk of esophageal varices in patients with compensated advanced chronic liver disease. Performing spleen stiffness measurement together with liver stiffness measurement during the same examination is simple and fast and this sequential model can identify a greater number of patients that can safely avoid endoscopy, which is an invasive and expensive examination.

Usefulness of liver stiffness measurement in predicting hepatic veno-occlusive disease development in patients who undergo HSCT.

Hepatic veno-occlusive disease (VOD), or sinusoidal obstructive syndrome (SOS), is a clinical syndrome characterized by hepatomegaly, ascites, weight gain and jaundice, which can develop more frequently in the first 30 days after hematopoietic stem cell transplantation (HSCT).1, 2 Its incidence, although influenced by diagnostic criteria, has been estimated to be 13.7% (range 0–62.3%) and, in untreated hepatic severe VOD/SOS, it is associated with >80% mortality.3 In this syndrome, sinusoidal endothelial cells and hepatocytes in zone 3 of the hepatic acinus are damaged by toxic metabolites generated during the conditioning regimen.4 The classic VOD pathway develops by the narrowing of the sinusoids, embolization of endothelial cells and increased clot formation, leading to obstruction of the sinusoids, subendothelial and centro-acinar fibrosis and then to portal-central fibrosis resulting in post-sinusoidal portal hypertension, which dominates the clinical picture.5

Spleen Stiffness by Ultrasound Elastography

This chapter reviews the use of spleen stiffness measurements (SSM) by ultrasound elastography technique. SSM represents a new, useful, non-invasive tool able to help the hepatologist in the management of the patient with liver diseases and different clinical presentations.

Noninvasive Assessment of Portal Hypertension in Advanced Chronic Liver Disease: An Update

The assessment of portal hypertension is a relevant step in the evaluation of newly diagnosed advanced chronic liver disease (ACLD). The current gold standard includes the invasive evaluation of hepatic venous pressure gradient (HVPG) and endoscopy. However, noninvasive or minimally invasive techniques to assess portal hypertension have been proposed and well established. In the present manuscript, we review clinical studies on the use of noninvasive or minimally invasive techniques to assess portal hypertension in ACLD patients.

Spleen stiffness mirrors changes in portal hypertension after successful interferon-free therapy in chronic-hepatitis C virus patients

AIM To investigate changes in spleen stiffness measurements (SSMs) and other non-invasive tests (NITs) after treatment with direct-acting antivirals (DAAs) and identify predictors of SSM change after sustained virological response (SVR). METHODS We retrospectively analysed 146 advanced-chronic liver disease (ACLD) patients treated with DAA with available paired SSM at baseline and SVR24. Liver stiffness (LSM), spleen diameter (SD), platelet count (PLT) and liver stiffness-spleen diameter to platelet ratio score(LSPS) were also investigated. LSM ≥ 21 kPa was used as a cut-off to rule-in clinically significant portal hypertension (CSPH). SSM reduction > 20% from baseline was defined as significant. RESULTS SSM significantly decreased at SVR24, in both patients with and without CSPH; in 44.8% of cases, SSM reduction was > 20%. LSPS significantly improved in the entire cohort at SVR24; SD and PLT changed significantly only in patients without CSPH. LSM significantly decreased in 65.7% of patients and also in 2/3 patients in whom SSM did not decrease. The independent predictor of decreased SSM was median relative change of LSM. CSPH persisted in 54.4% patients after SVR. Delta LSM and baseline SSM were independent factors associated with CSPH persistence. CONCLUSION SSM and other NITs significantly decrease after SVR, although differently according to the patient’s clinical condition. SSM faithfully reflects changes in portal hypertension and could represent a useful NIT for the follow-up of these patients.

How to clarify the Baveno VI criteria for ruling out varices needing treatment by noninvasive tests

Baveno VI criteria enabled the screening of varices needing treatment (VNT) without endoscopy but created confusion by not stating the method used to calculate the 5% missed VNT limit, resulting in different calculations across validation studies. We analysed those calculations to clarify their diagnostic meaning.

Immune inflammation indicators and ALBI score to predict liver cancer in HCV-patients treated with direct-acting antivirals

BACKGROUND Unexpectedly high occurrence or recurrence rate of hepatocellular carcinoma (HCC) has been observed in patients with chronic hepatitis C receiving direct-acting antivirals (DAAs) therapy. AIMS We evaluated the predictive value of albumin-bilirubin (ALBI) score and immune-inflammation indicators to identify the risk of occurrence or recurrence of HCC in patients treated with DAAs in a real life setting. METHODS In this retrospective cohort study, we analysed data from 514 patients with cirrhosis who were prospectively enrolled for treatment with DAAs. We assessed baseline neutrophil to lymphocyte ratio (NLR), systemic immune-inflammation index (SII), platelet to lymphocyte ratio (PLR), aspartate aminotransferase-lymphocyte ratio (ALRI) index and ALBI score. RESULTS In patients with no history of HCC (N = 416), increased AST, bilirubin, ALRI, and ALBI score, and decreased albumin and platelets were significantly associated with an increased risk of HCC development, at univariate analysis. At multivariate analysis, increase in ALBI grade (p = 0.038, HR: 2.35, 95% CI: 1.05-5.25) and decrease in platelets (p = 0.048, HR: 0.92, 95% CI: 0.85-1.0) were independently associated with HCC development. In patients with previous HCC (N = 98), adjusting for the time from HCC treatment, increased ALRI (p = 0.008, HR: 1.05, 95% CI: 1.01-1.09) was significantly associated with a risk of recurrence. CONCLUSION ALBI score, platelet count and ALRI are promising, easy to perform and inexpensive tools for identifying patients with higher risk of HCC after treatment with DAAs.

Hepatocellular carcinoma risk assessment by the measurement of liver stiffness variations in HCV cirrhotics treated with direct acting antivirals

BACKGROUND Direct-acting antivirals (DAA) are an effective treatment for hepatitis C virus infection. However, sustained virologic response (SVR) after DAA treatment does not seem to reduce the risk of hepatocellular carcinoma (HCC) development in these patients. Liver stiffness measurement (LSM) may predict the risk of developing HCC in liver cirrhosis patients. AIMS The aim of our study was to evaluate the role of LSM variation as predictor of HCC development in patients treated with DAA. METHODS In 139 HCV-related cirrhotic patients, LSM and laboratory tests were carried out at baseline (BL) and at the end of DAA treatment (EOT). Patients were followed for at least 6 months after the EOT. LSM reduction was expressed as Delta LS (∆LS). Cox regression analysis was used to identify prognostic factors for HCC development after DAA. RESULTS Median LSM values were significantly reduced from BL to EOT (from 18.6 to 13.8 kPa; p < 0.001). The median ∆LS was -26.7% (IQR: -38.4% -13.6%). During a median follow-up of 15 months after DAA treatment, 20 (14.4%) patients developed HCC. Significant LSM reduction was observed both in patients who developed HCC and in those who did not, but this was significantly lower in the patients who developed HCC (-18.0% vs -28.9% p = 0.005). At multivariate analysis, ∆LS lower than -30%, Child-Turcotte-Pugh-B and history of HCC were independently associated with HCC development. CONCLUSION Our results indicate that ∆LS is a useful non-invasive marker for predicting HCC development after DAA treatment.