Mutations in the RINT1 gene represent a rare genetic cause of recurrent fever-associated acute liver failure (ALF) accompanied by skeletal abnormalities in infants and children. We report the case of a 9-month-old infant presenting with multisystem involvement, primarily characterized by recurrent fever-associated ALF and cranial dysmorphism, due to compound heterozygous mutations in the RINT1 gene. The patient exhibited abnormal liver function tests and coagulation dysfunction following febrile episodes. Over a period of more than one year, the patient initially experienced two episodes of acute liver injury, followed by two episodes of ALF, with progressively worsening clinical manifestations. Whole-exome sequencing (WES) identified compound heterozygous variants in the RINT1 gene (exons 12-14 deletion; intron 11, c.1672-1G > T, p.?), consistent with a diagnosis of infantile liver failure syndrome-3 (ILFS3). Between episodes, liver function failed to return fully to baseline and was accompanied by growth retardation, delayed psychomotor development, cranial dysmorphism, and beak-like deformities of vertebral bodies. This case highlights the critical role of RINT1 mutations in the pathogenesis of recurrent fever-associated ALF and emphasizes the importance of recognizing associated skeletal developmental abnormalities, including cranial dysmorphism. Early genetic diagnosis and prompt antipyretic intervention may mitigate liver injury and improve long-term outcomes. By documenting cranial dysmorphism in this context, we aim to expand the recognized phenotypic spectrum of ILFS3 and improve clinical awareness among pediatricians and geneticists.

Since described in 2015, NBAS-associated disease has emerged as an important cause of acute liver failure (ALF) in children. We analysed the variable expression, genotype-phenotype association, outcome and prognostic factors of the hepatic involvement. Individuals with biallelic pathogenic NBAS variants were recruited within an international observational study, including new and previously published patients. We studied 230 individuals, including 13 previously unreported patients. The liver was the most frequently affected organ (63.4%), with 41.3% experiencing at least one ALF. The median age at onset was 0.9 years, the median age at last ALF 5 years, the latest ALF occurred at 24 years. Liver crises were triggered by febrile infections and presented with highly increased hepatic transaminases. Liver involvement varied significantly between the subgroups: 91.7% of patients with infantile liver failure syndrome type 2 and 88.9% of patients from the combined subgroup (variants affecting β-propeller domain) presented with ALF, whereas SOPH (stature, optic atrophy, Pelger-Huët anomaly) patients mostly had either no liver involvement (66.4%) or persistently elevated transaminases without ALF (28%). The rate of native liver survival was 83.9%; 16 individuals underwent liver transplantation and 24 died. Liver abnormalities are common and the leading cause of death in NBAS-associated disease. There is a clear genotype-phenotype association regarding the hepatic involvement. Liver crises occur primarily during infancy; however, early medical attention in case of febrile infections is necessary at all ages. Liver transplantation prevents ALF, but its risks must be weighed against the frequency and severity of liver crises decreasing with age.

Leucine aminoacyl tRNA-synthetase 1 (LARS1)-deficiency (infantile liver failure syndrome type 1 (ILFS1)) has a multisystemic phenotype including fever-associated acute liver failure (ALF), chronic neurologic abnormalities, and encephalopathic episodes. In order to better characterize encephalopathic episodes and MRI changes, 35 cranial MRIs from 13 individuals with LARS1 deficiency were systematically assessed and neurological phenotype was analyzed. All individuals had developmental delay and 10/13 had seizures. Encephalopathic episodes in 8/13 were typically associated with infections, presented with seizures and reduced consciousness, mostly accompanied by hepatic dysfunction, and recovery in 17/19 episodes. Encephalopathy without hepatic dysfunction occurred in one individual after liver transplantation. On MRI, 5/7 individuals with MRI during acute encephalopathy had deep gray matter and brainstem changes. Supratentorial cortex involvement (6/13) and cerebellar watershed injury (4/13) occurred with seizures and/or encephalopathy. Abnormal brainstem contour on sagittal images (8/13), atrophy (8/13), and myelination delay (8/13) were not clearly associated with encephalopathy. The pattern of deep gray matter and brainstem changes are apparently characteristic of encephalopathy in LARS1-deficiency, differing from patterns of hepatic encephalopathy or metabolic stroke in organic acidurias and mitochondrial diseases. While the pathomechanism remains unclear, fever and energy deficit during infections might be causative; thus, sufficient glucose and protein intake along with pro-active fever management is suggested. As severe episodes were observed during influenza infections, we strongly recommend seasonal vaccination.

Mitochondrial DNA depletion syndromes (MDDS) are a heterogeneous group and the hepato-cerebral phenotype is highly variable. A single centre retrospective study of all patients with MDDS presenting between January 2002 and September 2019. In total, 24 (13 male) children were identified: 7 POLG, 7 DGUOK, and 10 MPV17. Median age at presentation was 3 months (0.06-189). Sixteen had acute liver failure (ALF) and eight chronic cholestasis and/or raised transaminases. Four POLG patients developed liver injury after starting sodium valproate; Six DGUOK patients had neonatal ALF (median age 12 days), liver involvement developed at a median age of 2.5 and 11 months with MPV17 and POLG patients, respectively. Eighteen patients showed neurological involvement. Liver histology from 10 patients showed variable degrees of necrosis, steatosis, cholestasis, and fibrosis. Mitochondrial respiratory chain enzymology was abnormal in 5. Seventeen patients died at a median age of 8 months (range, 1-312) after a median time of 5.6 months from presentation: 5/7 POLG at 53 months, 7/7 DGUOK at 8 months and 5/10 MPV17 at 8 months. Three patients with MPV17 mutations received liver transplant (LT) at a median age of 24 months (range 5-132): all alive at 19, 18 and 3 years post-LT. Mutations in DGUOK and MPV17 genes are associated with a severe clinical phenotype characterised by early-onset/neonatal ALF or rapidly progressive cholestasis and death before 12 months of age. A subset of MPV17 patients was amenable to LT. Consideration for LT in infantile ALF remains difficult and rapid genetic testing is advised.

To characterize clinical and laboratory signs of patients with Still's disease experiencing macrophage activation syndrome (MAS) and identify factors associated with MAS development. Patients with Still's disease classified according to internationally accepted criteria were enrolled in the AutoInflammatory Disease Alliance (AIDA) Still's Disease Registry. Clinical and laboratory features observed during the inflammatory attack complicated by MAS were included in univariate and multivariate logistic regression analysis to identify factors associated to MAS development. A total of 414 patients with Still's disease were included; 39 (9.4%) of them developed MAS during clinical history. At univariate analyses, the following variables were significantly associated with MAS: classification of arthritis based on the number of joints involved (p = 0.003), liver involvement (p = 0.04), hepatomegaly (p = 0.02), hepatic failure (p = 0.01), axillary lymphadenopathy (p = 0.04), pneumonia (p = 0.03), acute respiratory distress syndrome (p < 0.001), platelet abnormalities (p < 0.001), high serum ferritin levels (p = 0.009), abnormal liver function tests (p = 0.009), hypoalbuminemia (p = 0.002), increased LDH (p = 0.001), and LDH serum levels (p < 0.001). At multivariate analysis, hepatomegaly (OR 8.7, 95% CI 1.9-52.6, p = 0.007) and monoarthritis (OR 15.8, 95% CI 2.9-97.1, p = 0.001), were directly associated with MAS, while the decade of life at Still's disease onset (OR 0.6, 95% CI 0.4-0.9, p = 0.045), a normal platelet count (OR 0.1, 95% CI 0.01-0.8, p = 0.034) or thrombocytosis (OR 0.01, 95% CI 0.0-0.2, p = 0.008) resulted to be protective. Clinical and laboratory factors associated with MAS development have been identified in a large cohort of patients based on real-life data.