Non-alcoholic fatty liver disease associated with hypobetalipoproteinemia: report of three cases and a novel mutation in APOB gene

Background: Non-alcoholic fatty liver disease, the leading cause of chronic liver disease in children, is defined by hepatic fat infiltration >5% of hepatocytes, in the absence of excessive alcohol intake, evidence of viral, autoimmune or drug-induced liver disease. Conditions like rare genetic disorders must be considered in the differential diagnosis. Case Report: Two male brothers, and a non-related girl, all overweight, had liver steatosis. One of the brothers and the girl had elevated transaminases; all three presented with low total cholesterol, low density lipoproteins and very low density lipoproteins cholesterol levels, hypotriglyceridemia and low apolipoprotein B. A liver biopsy performed in the brother with citolysis confirmed steatohepatitis and the molecular study of apolipoprotein B gene showed a novel homozygous mutation (c.9353dup p.Asn3118Lysfs17). Patients with cytolysis lost weight, however liver steatosis persists. Conclusion: Fatty liver disease might be a consequence of hypobetalipoproteinemia. Evidence is scarce due to low number of reported cases.

A Novel Noonan Syndrome RAF1 Mutation: Lethal Course in a Preterm Infant

Noonan syndrome is a relatively common and heterogeneous genetic disorder, associated with congenital heart defect in about 50% of the cases. If the defect is not severe, life expectancy is normal. We report a case of Noonan syndrome in a preterm infant with hypertrophic cardiomyopathy and lethal outcome associated to acute respiratory distress syndrome caused by Adenovirus pneumonia. A novel mutation in the RAF1 gene was identified: c.782C>G (p.Pro261Arg) in heterozygosity, not described previously in the literature. Consequently, the common clinical course in this mutation and its respective contribution to the early fatal outcome is unknown. No conclusion can be established regarding genotype/phenotype correlation.