Acute Normoglycemic Ketoacidosis

A previously healthy 4-year-old boy presented with drowsiness and Kussmaul respiration following 2 days of abdominal pain, anorexia, and repeated vomiting. Venous blood pH was 7.07 (reference interval, 7.33–7.44); pCO2, 24 mm Hg (reference interval, 37–53); bicarbonate, 7.0 mmol/L (reference interval, 24–28); base excess, −21.6 mmol/L; and calculated anion gap, 23 mmol/L (reference interval, 3–11). Plasma glucose was 86 mg/dL (reference interval, 70–99) and lactate was 2.2 mmol/L (reference interval, 0.5–2.2). Urine dipstick testing was negative for glucose and strongly positive for ketones. Results of urine organic acid analysis by GC-MS are shown in Fig. 1. Fig. 1. Analysis of organic acids in the patient's urine by GC-MS. Abnormal metabolites are labeled in bold text. Urine organic acids were extracted into ethyl acetate/ether, converted to trimethylsilyl derivatives, and analyzed on an Agilent GC 7890A/MS 5975 system equipped with an Agilent HP-5MS (30 m, 0.25 mm × 0.25 μm) column. Internal standards (IS): 2-phenylbutyric, tropic, and margaric acids. The high anion gap implied accumulation of an abnormal acid rather than renal or gastrointestinal loss of bicarbonate as the cause of this …