A 2-MONTH-OLD boy presented with a history of 6 episodes of generalized 5-minute tonicoclonic seizures. Previously, he was well. His birth weight was 2780 g, and Apgar scores were 9 and 10 at 1 and 5 minutes, respectively. On hospital admission, he weighed 3540 g with a head circumference of 37 cm. He was afebrile, hypotonic, drowsy, and pale. His blood pressure was 95/55 mm Hg; pulse rate, 100/min; and respirations, 30/min. The anterior fontanelle was soft, the pupils were equal and reactive to light, and no retinal hemorrhages were present at funduscopy. Findings from pulmonary and cardiac auscultation and abdominal examination were normal. Blood serum values from laboratory test results were as follows: glucose, 6.8 mmol/L (122 mg/dL); calcium, 0.78 mmol/L (3.1 mg/dL); phosphorus, 0.16 mmol/L; magnesium, 0.78 mmol/L (1.9 mg/dL); sodium, 143 mmol/L; potassium, 5.3 mmol/L; chloride, 113 mmol/L; and bicarbonate, 17 mmol/L. The hemoglobin value was 76 g/L; mean corpuscular volume, 74 fL/L; total white blood cell count, 11.5 × 109/L with 0.22 neutrophils; and platelet count, 150 × 109/L. Arterial blood gas showed a pH of 7.34; PaCO2, 29 mm Hg; PaO2, 90 mm Hg; and a base deficit of 6 mEq/L. The corrected QTc interval on electrocardiogram was 0.49 seconds, and the rhythm was regular. Findings from urinalysis and antigen studies were normal, and cerebrospinal fluid showed no white cells. Levels for protein and cerebrospinal fluid glucose were 24 g/L and 4.2 mmol/L (76 mg/dL), respectively. No organisms were present on the Gram stain and none were found in blood and urine culture samples. Findings from an electroencephalogram showed mild discharge in the left posterior temporal area. A skull radiograph was requested (Figure 1), followed by radiography of the hands (Figure 2).