Alagille Syndrome Candidates for Liver Transplantation: Differentiation from End-Stage Biliary Atresia Using Preoperative CT

Different clinical and genetic features of Alagille patients with progressive disease versus a jaundice-free course

Background and Aim

Alagille syndrome (ALGS) is a multisystem disorder with variable clinical courses. This study investigated the clinical and genetic features of ALGS patients with different outcomes and analyzed the liver pathology at liver transplantation (LT) compared with that in biliary atresia (BA).

Methods

We report the clinical characteristics, outcomes, and genetic mutations of 25 children with ALGS followed for a median of 7.3 years. Patients were classified into (i) jaundice-free (JF) group (resolving jaundice after 2 years of age); (ii) progressive disease (PD) group (persistent jaundice or progressive cholestasis). In addition, we analyzed the explant liver in 10 ALGS patients compared with 20 age-matched BA patients at the time of LT.

Results

Nine patients (36%) in the JF group had a favorable outcome, with longer native liver survival than patients with PD (n = 16, P < 0.001). Fourteen of the PD group patients received LT or died. We identified 18 different JAG1 mutations in 22 patients. Three unrelated probands in the JF group had the same de novo mutation in JAG1, c.2122-2125delCAGT. Compared with BA children, ALGS patients had lower METAVIR scores in liver pathology, higher serum albumin levels, and lower weight-for-age z-scores when receiving LT.

Conclusion

One-third of ALGS patients had JF and a favorable course. Children with ALGS presenting with persistent jaundice beyond 2 years of age should be cautioned for poor prognosis. ALGS patients tend to have a lesser extent of cirrhosis, and more growth problems than BA patients at the time of LT.

A case of infantile Alagille syndrome with severe dyslipidemia: a new insight into lipid metabolism and therapeutics

Alagille syndrome (AGS) is an autosomal dominant genetic disorder characterized by congenital heart disease, hepatic cholestasis, dyslipidemia, and characteristic facies since infancy. Cholestatic hypercholesterolemia in patients diagnosed with AGS is occasionally refractory and resistant to conventional treatments. We report the case of a 4-month-old boy diagnosed with AGS and refractory dyslipidemia due to cholestatic liver disease. He had repeated episodes of cyanosis due to pulmonary artery atresia since birth and underwent a Blalock-Taussig shunt procedure at age 3 months. At age 4 months, cholestatic hyperbilirubinemia deteriorated to a serum total bilirubin level of 19.9 mg/dL. At age 12 months, a laboratory test revealed severe dyslipidemia (serum total cholesterol, 1796 mg/dL; serum triglycerides [TGs], 635 mg/dL), and the presence of xanthomas. A pathogenic variant of the JAG1 gene (c.1326G > A, p.Trp442X) was detected through genetic testing. Oral ursodeoxycholate normalized hyperbilirubinemia with a subtle improvement in dyslipidemia. Combination therapy with pravastatin and fenofibrate did not successfully improve dyslipidemia. At age 20 months, altering pravastatin to atorvastatin was effective in normalizing serum cholesterol and TGs with no adverse events.

Combination therapy with atorvastatin and fenofibrate was successful in improving refractory dyslipidemia in a child with AGS. Atorvastatin is a well-known strong statin that can lower serum cholesterol, and fenofibrate can lower serum TG levels. We propose that atorvastatin be taken into consideration for the treatment of persistent hyperlipidemia in patients diagnosed with AGS, because atorvastatin upregulates bile acid synthesis and lipoprotein scavenging, and inhibits intrinsic cholesterol production.

Diffusion Tensor Imaging for Evaluating Biliary Atresia in Infants and Neonates

BACKGROUND

Preliminary studies have shown that diffusion tensor imaging (DTI) is helpful in evaluating liver disorders. However, there is no published literature on the use of DTI in the diagnosis of biliary atresia (BA). This study aimed to investigate the diagnostic value of the liver average apparent diffusion coefficient (ADC) and fractional anisotropy (FA) measured using DTI for BA in neonates and infants.

METHODS

Fifty-nine patients with infant jaundice were included in this study. DTI was performed with b factors of 0 and 1000 s/mm2. Liver fibrosis in the BA group was determined and graded (F0, F1, F2, F3, F4) based on the pathological findings. Statistical analyses were performed to determine the diagnostic accuracy of DTI for BA.

RESULTS

The ADC value was significantly lower in the BA group [(1.262±0.127)×10-3 mm2/s] than in the non-BA group [(1.430±0.149)×10-3 mm2/s, (P<0.001)]. The area under the receiver operating characteristic curve was 0.805±0.058 (P<0.001) for ADC. With a cut-off value of 1.317×10-3 mm2/s, ADC achieved a sensitivity of 75% and a specificity of 81.5% for the differential diagnosis of BA and non-BA. In the BA group, the ADC value was significantly correlated with fibrotic stage. Further analysis showed that the ADC value of stage F0 was significantly higher than that of stages F1, F2, F3 and F4, whereas there were no significant differences among stages F1, F2, F3 and F4.

CONCLUSION

Hepatic ADC measured with DTI can be used as an adjunct to other noninvasive imaging methods in the differential diagnosis of BA and non-BA. ADC was helpful in detecting liver fibrosis but not in differentiating the fibrotic grades.