Long-term follow-up of portal hypertension after liver transplantation in children

Sinusoidal and pericellular fibrosis in adult post-transplant liver biopsies: association with hepatic stellate cell activation and patient outcome

Post-transplant sinusoidal fibrosis (SF) and pericellular fibrosis (PCF) have not been extensively investigated in adults. Fifty-two post-transplant liver biopsies from 28 consented patients (12 men, mean age 49, range 33–67 years) were studied. Tissue morphology, including an arbitrary summative fibrosis score was assessed in detail. Collagen proportionate area (CPA) and alpha-smooth muscle actin (α-SMA) immunostain were evaluated by digital image analysis (DIA). Anti-keratin 7, anti-C4d and anti-sonic hedgehog (Shh) immunostains were scored semi-quantitatively. SF was observed in 36/52 (69.2%) biopsies and most of these (20/36, 55.6%) had centrilobular fibrosis (CLF). PCF was seen in 7/52 (13.5%) biopsies exclusively in cases with CLF. CPA was significantly correlated with time since liver transplantation (p = 0.043), summative fibrosis score and its main components but not with α-SMA. α-SMA-positive area significantly correlated with the Banff rejection score (p = 0.022) and centrilobular inflammatory changes were more severe in cases with CLF (p = 0.003). Hepatocyte ballooning of cholestatic type was associated with PCF (p = 0.016) and Shh expression (p < 0.001). Sinusoidal fibrosis is a frequent occurrence in post-transplant adult livers, with predilection toward centrilobular areas. Graft age and oxidative stress may contribute to SF development, while hepatocyte ballooning may be implicated in PCF development. Hepatic stellate cell (HSC) activation is likely affected by centrilobular inflammation.

Liver Stiffness Measured by Shear-wave Elastography for Evaluating Intrahepatic Portal Hypertension in Children

OBJECTIVES

The aim of the study was to correlate liver stiffness (LS) and hepatic venous-pressure gradient (HVPG) and to evaluate the diagnostic performance of shear-wave elastography (SWE) for predicting clinically significant portal hypertension in children with suspected liver diseases, in consideration of the reliability criteria.

METHODS

We identified 33 SWEs from 32 children who underwent HVPG measurement within 2 weeks between June 2012 and October 2015. The correlation between LS and HVPG was assessed. The diagnostic performance for predicting clinically significant portal hypertension (HVPG ≥ 10 mmHg) was assessed using the receiver-operating characteristic curve. Reliable measurement was evaluated based on the coefficient of variation (CV).

RESULTS

LS was significantly correlated with HVPG (r = 0.742, P < 0.001). The area under the receiver-operating characteristic curve for predicting clinically significant portal hypertension was 0.914, and the best cutoff value of 18.4 kPa showed sensitivity of 87.5% and specificity of 84.0%. LS measurements having CV ≤ 0.2 were significantly correlated with HVPG (r = 0.774, P < .001), whereas those having CV > 0.2 did not show a significant correlation with HVPG (r = 0.598, P = 0.089).

CONCLUSIONS

SWE had excellent diagnostic performance for predicting clinically significant portal hypertension in children with suspected liver diseases. LS measurements having CV ≤ 0.2 may possibly be used as a reliability criterion in SWE measurement.

Usefulness of magnetic resonance angiography for the evaluation of varices at hepaticojejunostomy after liver transplantation

A 7-year-old Japanese girl who had undergone living-donor liver transplantation (LT) at the age of 10 months for decompensated liver cirrhosis caused by biliary atresia presented with recurrent episodes of obscure gastrointestinal bleeding (GIB) with anemia. Over the following 6 years, she experienced five episodes of GIB requiring hospitalization. Subsequent evaluations including repeat esophagogastroduodenoscopy (EGD), colonoscopy (CS), contrast-enhanced computed tomography (CT), and Meckel's scan all failed to reveal a bleeding source. However, varices at the site of hepaticojejunostomy were detected on abdominal ultrasonography and magnetic resonance angiography (MRA) at the age of 7 years. MRA might be more helpful than contrast-enhanced CT for identifying such bleeding.

Clinical significance of gastrointestinal bleeding after living donor liver transplantation

The clinical presentations of gastrointestinal bleeding (GIB) occurring after living donor liver transplantation (LDLT) have not been fully described. We performed a retrospective analysis of 297 LDLT cases. Nineteen patients (6.4%) experienced GIB after LDLT. The etiology of GIB included bleeding at the jejunojejunostomy following hepaticojejunostomy (n = 13), peptic ulcer disease (n = 2), portal hypertensive gastropathy (n = 2), and other causes (n = 2). Hemostasis was achieved in 13 patients (68.4%) by endoscopic (n = 3), surgical (n = 1), or supportive treatments (n = 15), but not in the other six patients. Graft dysfunction (P < 0.001), hepaticojejunostomy (P = 0.01), portal vein pressure at the end of surgery >20 mmHg (P = 0.002), and operative blood loss >10 L (P = 0.004) were risk factors. One-year graft survival rate was significantly lower in patients with GIB than in patients without GIB (P < 0.001). The inhospital mortality rate was 52.6% for patients with GIB, 75.0% for patients with graft dysfunction, and 14.3% for patients without graft dysfunction (P = 0.028). Despite its infrequency after LDLT, GIB has strong correlation with graft dysfunction and inhospital mortality.

Roux-en-Y loop varices in children with portal hypertension after liver transplantation: an unusual cause of "obscure" gastrointestinal bleeding

PHALT may result from graft dysfunction, portal vein thrombosis, arterio-venous fistulas and can lead to GIB, commonly from bleeding esophageal varices. We present three children with GIB requiring multiple blood transfusions that were diagnosed with RY Loop bleeding. Routine EGD, colonoscopy, and CE failed to reveal the bleeding source. However, enteroscopy revealed large varices at the site of hepaticojejunostomy anastomosis in all. Our experience demonstrates that RY loop varices in children with PHALT are a rare and treatable cause of obscure GI bleeding.

Persistent portosystemic shunts after liver transplantation causing episodic hepatic encephalopathy

We describe two cases of post liver transplant encephalopathy caused by persistent portosystemic shunts despite good graft function. Such recurrence of encephalopathy due to persistent shunting has not been reported in the deceased donor liver transplant literature. Our patients had episodic hepatic encephalopathy concordant with elevated serum ammonia levels due to well documented persistent portosystemic shunts. In one of our cases, the shunt was obliterated via coil embolization. This patient's encephalopathy resolved completely and has not recurred over seven months of follow up. The second patient has declined an intervention, but has remained symptom free on maintenance lactulose and rifaximin.