A 45-year-old man is brought to the emergency department by ambulance after vomiting blood. The patient reports that he only ate a small snack the morning before and had not eaten anything for over 24 hours. At the hospital, the patient is stabilized. He is admitted to a surgical floor and placed on NPO with a nasogastric tube set to intermittent suction. He has been previously diagnosed with liver cirrhosis. An esophagogastroduodenoscopy (EGD) has been planned for the next afternoon. At the time of endoscopy, some pathways were generating glucose to maintain serum glucose levels. Which of the following enzymes catalyzes the irreversible biochemical reaction of this process?
AGlucose-6-phosphate dehydrogenase
BGlycogen phosphorylase
CEnolase
DGlyceraldehyde-3-phosphate dehydrogenase
EFructose-1,6-bisphosphatase
A 3-week-old male is brought to the emergency department because of increasing lethargy. He was born at home without prenatal care or neonatal screening and appeared to be normal at birth. Despite this, his parents noticed that he would vomit after breastfeeding. He then progressively became more lethargic and began to have a few episodes of diarrhea after feeding. His parents do not recall any significant family history and neither of his siblings have had similar symptoms. Upon presentation, the infant is found to be generally unresponsive with mild hepatomegaly. Physical exam further reveals signs of clouding in the lenses of his eyes bilaterally. The levels of which of the following metabolites will be most dramatically elevated in this patient?
AFructose
BLactose
CGalactose
DGalactose-1-phosphate
EFructose-1-phosphate
A 3-week-old newborn is brought to the pediatrician by his mother. His mother is concerned about her son’s irritability and vomiting, particularly after breastfeeding him. The infant was born at 39 weeks via spontaneous vaginal delivery. His initial physical was benign. Today the newborn appears mildly jaundiced with palpable hepatomegaly, and his eyes appear cloudy, consistent with the development of cataracts. The newborn is also in the lower weight-age percentile. The physician considers a hereditary enzyme deficiency and orders blood work and a urinalysis to confirm his diagnosis. He recommends that milk and foods high in galactose and/or lactose be eliminated from the diet. Which of the following is the most likely deficient enzyme in this metabolic disorder?
AAldose reductase
BGalactose-1-phosphate uridyl transferase
CUDP-galactose-4-epimerase
DGalactokinase
EGlucose-6-phosphate dehydrogenase
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