β-Ketothiolase Deficiency has a variable presentation. Most affected patients present between 5 and 24 months of age with symptoms of severe ketoacidosis. Symptoms can be initiated by a dietary protein load, infection or fever. Symptoms progress from vomiting to dehydration and ketoacidosis.  Neutropenia and thrombocytopenia may be present, as can moderate hyperammonemia. Blood glucose is typically normal, but can be low or high in acute episodes.  Developmental delay may occur, even before the first acute episode, and bilateral striatal necrosis of the basal ganglia has been seen on brain MRI .