Inborn errors of metabolism (IEM) are a hetergenous group of disorders caused genetic defects in one or more metabolic pathways that can cause considerable morbidity and death. Up to now over 2500 IEMs have been described. While individually rare, the estimated global prevalence of IEMs comprises a substantial number of neonatal and infantile disorders affecting the CNS. These are difficult disorders to diagnose, because clinical manifestations are often nonspecific and radiological findings are often overlapping. This makes them a difficult topic for both clinicians and radiologists.

In this presentation imaging findings are shown of three IEMs in which patients classically present with an increased head circumference (macrocephaly) during the first year of life. When confronted with a leukodystrophy on imaging in a child presenting with macrocephaly, differential diagnosis is not that extensive and includes Alexander disease, Canavan disease and Van Der Knaap disease. Although all three of these disorders are characterzied by diffuse WM abnormalities on imaging, there are sufficient radiological differences to suggest the correct diagnosis.

0:00 - Introduction
01:44 - Case presentation
10:24 - Alexander disease
17:30 - Canavan disease
24:41 - Megalencephalic leukoencephalopathy with subcortical cysts (Van Der Knaap disease)
32:35 - Key Messages

#radiology #neuroradiology #neurology #medicalstudent #neuroradiologist #theneuroradiologist #MRI #medical #pediatrics #leukodystrophy #genetics #alexander #canavan #pediatricneurology