In conditions that can present more acutely (Cases 4–6), there is also a superimposed risk of metabolic decompensation (vascular events in CBS deficiency, potentially lethal metabolic encephalopathy in MSUD, acute pancreatitis in genetic hypertriglyceridemias) [12, 22, 23]. Here, CBS is linked to hyperinsulinemic hypoglycemia, familial, 4.