Giusy Ranucci

Re‐evaluation of the diagnostic criteria for Wilson disease in children with mild liver disease

The diagnosis of Wilson disease (WD) is challenging, especially in children. Early detection is desirable in order to avoid dramatic disease progression. The aim of our study was to re‐evaluate in WD children with mild liver disease the conventional diagnostic criteria and the WD scoring system proposed by an international consensus in 2001. Forty children with WD (26 boys and 14 girls, age range = 1.1‐20.9 years) and 58 age‐matched and sex‐matched patients with a liver disease other than WD were evaluated. Both groups were symptom‐free and had elevated aminotransferases as predominant signs of liver disease. In all WD patients, the diagnosis was supported by molecular analysis, the liver copper content, or both. A receiver operating characteristic (ROC) analysis of ceruloplasmin at the cutoff value of 20 mg/dL showed a sensitivity of 95% [95% confidence interval (CI) = 83%‐99.4%] and a specificity of 84.5% (95% CI = 72.6%‐92.6%). The optimal basal urinary copper diagnostic cutoff value was found to be 40 μg/24 hours (sensitivity = 78.9%, 95% CI = 62.7%‐90.4%; specificity = 87.9%, 95% CI = 76.7%‐95%). Urinary copper values after penicillamine challenge did not significantly differ between WD patients and control subjects, and the ROC analysis showed a sensitivity of only 12%. The WD scoring system was proved to have positive and negative predictive values of 93% and 91.6%, respectively. Conclusion: Urinary copper excretion greater than 40 μg/24 hours is suggestive of WD in asymptomatic children, whereas the penicillamine challenge test does not have a diagnostic role in this subset of patients. The WD scoring system provides good diagnostic accuracy. (HEPATOLOGY 2010.)

Leptin: The Prototypic Adipocytokine and its Role in NAFLD

Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome, whose pathogenesis begins with the accumulation of liver fat and is followed by the development of necro-inflammation and fibrosis. Recent evidence indicates that adipocytokines, polypeptides secreted by the adispose tissue, might play an important role in the pathogeneic process and progression of NAFLD. In this review, we explore the role of leptin, and in part of other adipocytokines, in the interference with hepatic injury associated with fatty infiltration, in the modulation of steatosis and fibrosis, in both experimental models of the disease and in the clinical practice. We also discuss the potential use of leptin as non-invasive marker for differentiating simple fatty liver from NAFLD, and the possible novel therapeutic strategies aimed at interfering with the leptin axis to dampen chronic liver inflammation and NAFLD.

Subclinical neurological involvement does not develop if Wilson's disease is treated early

BACKGROUND & AIMS Wilsons disease (WD) is a genetic disorder of copper metabolism causing dysfunctions of various organs, mostly the liver and brain. If untreated, WD is fatal, but early treatment results in a good prognosis, although the long-term neurological outcome has not yet been clarified. To address this issue, we evaluated the neurological status of early-treated WD patients without overt nervous system impairment using neurophysiological, neuropsychological and neuroimaging procedures at least 10 years after treatment onset. METHODS Thirty-eight WD patients (18 females, aged 24.47 ± 7.50 years), who received an early diagnosis (in presymptomatic or mild/moderate liver disease stages without neurological involvement) and prompt treatment, were clinically evaluated with the Global Assessment Scale. Presentation was hepatic in 36 subjects (95%), while 2 patients (5%) were presymptomatic. A neurophysiological study was performed to explore the central motor conduction time of the upper and lower limbs, and motor cortex excitability using single pulses and paired-pulse transcranial magnetic stimulation. Neuroimages were obtained with brain magnetic resonance scans. Cognitive abilities, and psychiatric and behavioral disturbances were evaluated with neuropsychological tests. RESULTS Patients were undergoing treatment with penicillamine (7 patients) or zinc salts (31 patients) with good adherence. They did not present any neurological signs at clinical evaluation or at specific scale of impairment, the mean Global Assessment Scale score was 0.3 ± 0.7. Magnetic resonance imaging, transcranial magnetic stimulation studies and neuropsychological/neuropsychiatric assessment ruled out subclinical involvement. CONCLUSIONS This study suggests that early diagnosis and treatment of WD may prevent the onset of neurologic damage, even at subclinical level.

Autoimmune Hepatitis Type 2 Arising in PFAPA Syndrome: Coincidences or Possible Correlations?

PFAPA syndrome is a chronic disease classified in the group of autoinflammatory syndromes characterized by periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis in young children. The etiology of this disorder is still unknown, but a primary dysfunction of the innate immune system seems to be involved. According to Marshall criteria, it is not possible to diagnose PFAPA in the presence of autoimmune diseases. We present here the case report of an 8-month girl with PFAPA who developed autoimmune hepatitis type 2 at the age of 18 months. We suppose that the dysregulation in innate immunity that is typical of patients with PFAPA could trigger autoimmune disorders such as autoimmune hepatitis in susceptible subjects. The possible relationships between immune-system dysfunction peculiar to this syndrome and autoimmune hepatitis are discussed.

Wilson's disease caused by alternative splicing and Alu exonization due to a homozygous 3039-bp deletion spanning from intron 1 to exon 2 of the ATP7B gene.

We describe a case of Wilsons disease (WD) diagnosed at 5 years after routine biochemical test showed increased aminotransferases. Mutation analysis of the ATP7B gene revealed a 3039-bp deletion in the homozygous state spanning from the terminal part of intron 1 to nt position 368 of exon 2. This deletion results in the activation of 3 cryptic splice sites: an AG acceptor splice site in nt positions 578-579 producing a different breakpoint and removing the first 577 nts of exon 2, an acceptor and a donor splice site in nt positions 20363-4 and 20456-7, respectively, in intron 1, resulting in the activation of a 94-bp cryptic Alu exon being incorporated into the mature transcript. The resulting alternative transcript contains a TAG stop codon in the first amino acid position of the cryptic exon, likely producing a truncated, non-functional protein. This study shows that intron exonization can also occur in humans through naturally occurring gross deletions. The results suggest that the combination of DNA and RNA analyses can be used for molecular characterization of gross ATP7B deletions, thus improving genetic counseling and diagnosis of WD. Moreover these studies help to better establish new molecular mechanisms producing Wilsons disease.

Wilson’s disease: Prospective developments towards new therapies

Wilson’s disease (WD) is an autosomal recessive disorder of copper metabolism, caused by mutations in the ATP7B gene. A clear demand for novel WD treatment strategies has emerged. Although therapies using zinc salts and copper chelators can effectively cure WD, these drugs exhibit limitations in a substantial pool of WD patients who develop intolerance and/or severe side effects. Several lines of research have indicated intriguing potential for novel strategies and targets for development of new therapies. Here, we review these new approaches, which comprise correction of ATP7B mutants and discovery of new compounds that circumvent ATP7B-deficiency, as well as cell and gene therapies. We also discuss whether and when these new therapeutic strategies will be translated into clinical use, according to the key requirements for clinical trials that remain to be met. Finally, we discuss the hope for the current rapidly developing research on molecular mechanisms underlying WD pathogenesis and for the related potential therapeutic targets to provide a solid foundation for the next generation of WD therapies that may lead to an effective, tolerable and safe cure.

Wilson disease: what is still unclear in pediatric patients?

Since Wilson disease (WD) may not be present with evident clinical symptoms of liver injury and neurological presentation is rare in children, establishing a diagnosis is often challenging, especially in childhood. Increased transaminases can be the only abnormality found in early course of WD. In clinical practice, high suspicion is crucial for early diagnosis and timely treatment to ensure better outcomes. Conventional diagnostic criteria established for adults are commonly agreed for children but may not always be appropriate in very young age. Currently, the best therapeutic approach for each specific presentation of the disease remains controversial and there are no clear indications about how to treat pediatric WD patients with a mild liver disease.

Characterization of the most frequent ATP7B mutation causing Wilson disease in hepatocytes from patient induced pluripotent stem cells

H1069Q substitution represents the most frequent mutation of the copper transporter ATP7B causing Wilson disease in Caucasian population. ATP7B localizes to the Golgi complex in hepatocytes but moves in response to copper overload to the endo-lysosomal compartment to support copper excretion via bile canaliculi. In heterologous or hepatoma-derived cell lines, overexpressed ATP7B-H1069Q is strongly retained in the ER and fails to move to the post-Golgi sites, resulting in toxic copper accumulation. However, this pathogenic mechanism has never been tested in patients’ hepatocytes, while animal models recapitulating this form of WD are still lacking. To reach this goal, we have reprogrammed skin fibroblasts of homozygous ATP7B-H1069Q patients into induced pluripotent stem cells and differentiated them into hepatocyte-like cells. Surprisingly, in HLCs we found one third of ATP7B-H1069Q localized in the Golgi complex and able to move to the endo-lysosomal compartment upon copper stimulation. However, despite normal mRNA levels, the expression of the mutant protein was only 20% compared to the control because of endoplasmic reticulum-associated degradation. These results pinpoint rapid degradation as the major cause for loss of ATP7B function in H1069Q patients, and thus as the primary target for designing therapeutic strategies to rescue ATP7B-H1069Q function.

Successful Use of Ursodeoxycholic Acid in Nodular Regenerative Hyperplasia of the Liver

Objective: To report, to our knowledge, the first case of a patient with nodular regenerative hyperplasia of the liver (NRHL) associated with portal hypertension in whom ursodeoxycholic acid (UOCA) therapy had a therapeutic effect on liver enzymes and was associated with nonprogression of portal hypertension. Case Summary: A symptom-free 13-year-old boy was hospitalized for splenomegaly and thrombocytopenia identified during a routine check-up. Infectious, autoimmune, and neoplastic causes were ruled out. Two years later, laboratory findings revealed high levels of aminotransferases and γ-glutamyltransferase (GGT), thrombocytopenia, and neutropenia. Ultrasound scanning of the abdomen confirmed portal hypertension. Results of liver pathology studies showed diagnostic features of NRHL Given the biochemical evidence of cholestasis, UDCA was administered, with an initial dosage of 10 mg/kg/day that was progressively increased to 20 mg/kg/day (1800 mg/day). After 5 months of treatment, GGT and then aminotransferase levels normalized and remained within normal limits in the following months. With arbitrary withdrawal of UDCA after 30 months of therapy, a rapid increase in transaminase levels was observed. Prompt reinstitution of UOCA was followed by sustained normalization of liver enzymes. Laboratory and sonographic signs of portal hypertension remained stable and tended to improve during UDCA therapy, as demonstrated by regularization of the mean portal vein flow velocity, reduction of the congestion index, progressive increase of the platelet count, and improvement of the esophagogastroscopy pattern. Discussion: NRHL is a rare disease that is characterized by multiple regenerative nodules in the hepatic parenchyma that may lead to noncirrhotic portal hypertension. No specific treatment is available, and management of patients with a primary form of NRHL consists mainly of treating the complications of portal hypertension. In our patient, UDCA therapy was followed by a prompt reduction and sustained normalization of liver enzyme levels and no progression of portal hypertension throughout the follow-up period. Conclusions: Since in this patient with primary NRHL, ongoing UDCA administration resulted in improved biochemical and portal hypertension markers, this therapy can be considered in cases of NRHL associated with abnormalities of liver enzymes.

SCYL1 variants cause a syndrome with low γ-glutamyl-transferase cholestasis, acute liver failure, and neurodegeneration (CALFAN)

AbstractPurposeBiallelic mutations in SCYL1 were recently identified as causing a syndromal disorder characterized by peripheral neuropathy, cerebellar atrophy, ataxia, and recurrent episodes of liver failure. The occurrence of SCYL1 deficiency among patients with previously undetermined infantile cholestasis or acute liver failure has not been studied; furthermore, little is known regarding the hepatic phenotype.MethodsWe aimed to identify patients with SCYL1 variants within an exome-sequencing study of individuals with infantile cholestasis or acute liver failure of unknown etiology. Deep clinical and biochemical phenotyping plus analysis of liver biopsies and functional studies on fibroblasts were performed.ResultsSeven patients from five families with biallelic SCYL1 variants were identified. The main clinical phenotype was recurrent low γ-glutamyl-transferase (GGT) cholestasis or acute liver failure with onset in infancy and a variable neurological phenotype of later onset (CALFAN syndrome). Liver crises were triggered by febrile infections and were transient, but fibrosis developed. Functional studies emphasize that SCYL1 deficiency is linked to impaired intracellular trafficking.ConclusionSCYL1 deficiency can cause recurrent low-GGT cholestatic liver dysfunction in conjunction with a variable neurological phenotype. Like NBAS deficiency, it is a member of the emerging group of congenital disorders of intracellular trafficking causing hepatopathy.