Magnetic resonance imaging features and neurodevelopmental prognosis in infants diagnosed with organic acidaemia

Aim To retrospectively examine the clinical characteristics, magnetic resonance imaging (MRI) findings, and neurodevelopmental outcomes of infants diagnosed with an organic acidaemia during their first year of life. Method This was an observational retrospective study. Infants who were diagnosed with an organic acidaemia before the age of 1 year and underwent cranial MRI at Peking University First Hospital between 2010 and 2020 were included. Clinical and MRI data were collected, and prognoses were classified based on developmental assessments. Results Sixty‐five children were included, with methylmalonic acidaemia combined with homocysteinaemia being the most prevalent type (40 of 65). Median age at onset was 2 months. Hydrocephalus was observed in 43% of children with methylmalonic acidaemia combined with homocysteinaemia, while thalamic and basal ganglia lesions were prominent in 83% of children with propionic acidaemia. All cases of glutaric aciduria type 1 exhibited extracerebral space widening. MRI findings were normal in eight children. Among the 47 children with available developmental data, 68% experienced severe neurodevelopmental impairments. Brainstem lesions may represent an independent risk factor for severe outcomes (odds ratio = 9.059, 95% confidence interval = 1.039–79.014, p = 0.046). Interpretation MRI patterns are essential in the diagnosis and prognostication of organic acidaemias, with brainstem lesions serving as a potential indicator of prognosis.