NBAS deficiency due to biallelic c.2809C > G variant presenting with recurrent acute liver failure with severe hyperammonemia, acquired microcephaly and progressive brain atrophy.

Biallelic pathogenic variants in the neuroblastoma amplified sequence (NBAS) gene were firstly (2015) identified as a cause of fever-triggered recurrent acute liver failure (RALF). Since then, some patients with NBAS deficiency presenting with neurologic features, including a motor delay, intellectual disability, muscular hypotonia and a mild brain atrophy, have been reported. Here, we describe a case of pediatric patient diagnosed with NBAS deficiency due to a homozygous c.2809C > G, p.(Pro937Ala) variant presenting with RALF with severe hyperammonemia, acquired microcephaly and progressive brain atrophy. Not reported in the literature findings include severe hyperammonemia during ALF episode, and neurologic features in the form of acquired progressive microcephaly with brain atrophy. The latter raises the hypothesis about a primary neurologic phenotype in NBAS deficiency.

Giant cell hepatitis with autoimmune hemolytic anemia in children: proposal for therapeutic approach.

BACKGROUND AND OBJECTIVE: Giant cell hepatitis (GCH) with autoimmune hemolytic anemia (AIHA) is a rare, progressive disorder in infants and young children. The disease is aggressive and may lead to liver or multiorgan failure with fatal prognosis. Therapy with anti-CD20 monoclonal antibody, rituximab (Rtx), proved effective. The primary objective of the study was to evaluate therapy for severe GCH with AIHA. METHODS: We report on 5 cases of severe GCH with AIHA treated in our department between 2006 and 2011. RESULTS: The median age of the children was 7 months (2-12 months), follow-up lasted 44 months (12-78 months), median (min-max), and the main observed symptoms were jaundice and hepatosplenomegaly. All of the children had positive direct Coombs test and biopsy-proven giant cell transformation of hepatocytes. Liver failure was observed in 3 children. First-line therapy (prednisone, azathioprine) proved ineffective in all but 1 of the patients, who initially responded to the treatment but relapsed after 4 months. The child subsequently developed hemophagocytic lymphohistiocytosis and died 2 months after hemopoietic stem cell transplantation. Four remaining patients finally achieved complete remission after 4 to 6 doses of Rtx. CONCLUSIONS: We propose Rtx as the treatment of choice for severe GCH with AIHA in the early stages of the disease, provided steroids and azathioprine are ineffective.