Intraventricular Glioblastoma Multiforme in A Child with L2-Hydroxyglutaric Aciduria.

L2-hydroxyglutaric aciduria (L2-HGA) is a rare neurometabolic disease characterized by accumulation of L2-hydroxyglutarate (L2-HG), a potential oncometabolite resulting in significant lifetime risk for cerebral tumors. Herein, we present a case of intraventricular glioblastoma multiforme (GBM) in a 16-year-old child with L2-HGA who presented with rapid functional decline and persistent vomiting. The tumor was completely resected, and the patient remained well at 2-year follow-up. Clinicians should be aware of the usual insidious nature of the disease. Rapid deterioration is unusual and should raise the suspicion of tumor development. This case also illustrates the importance of surveillance neuroimaging in patients with L2-HGA. To the best of our knowledge, only 1 case of GBM has been reported and it was sited in the temporal lobe, unlike the unusual intraventricular location in our case.