Quiz: Ace Your Exams

A 6-month-old girl is brought to the pediatrician’s office for evaluation of an enlarged abdomen. Her parents state they have noticed a bulging, protuberant belly over the past several weeks. Her mother has also noticed she has been increasingly irritable in between her feedings, and she often wakes up crying at night and is only consoled with feedings. During her periods of irritability, the patient is often sweating, which resolves with feeding. She is exclusively breastfed. Her birth was unremarkable; however, she has not been able to sit up or crawl. Her weight is less than the 5th percentile for her age. Temperature is 36.4°C (97.5°F), pulse is 122/min, blood pressure is 86/62 mmHg, and respiratory rate is 48/min. Physical examination reveals a lethargic infant. Facial examination reveals a rounded “doll's face-like” features with enlarged cheeks. Abdominal examination reveals massive and firm hepatomegaly. Genetic testing is performed, revealing a nonsense mutation in the gene encoding the enzyme glucose-6-phosphatase. Which of the following laboratory findings can be expected in this patient, considering the most likely diagnosis?