This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
[{'content': 'A 3-day child vomits everything he feeds, has a distended abdomen & diarrhoea. The urine is positive for benedicts test for reducing substance. The substance in urine is – \nSelect and explain. \nA. Sucrose, B. Glucose, C. Galactose, D. Fructose', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Characteristic symptom i.e., vomiting, distended abdomen and diarrhoea along with the presence of reducing a substance in the urine suggests the diagnosis of galactosemia\n\nGalactosemia \n\nGalactosemia is a group of metabolic disorders which occurs due to defect in the metabolism of galactose.\nThere is an inability to metabolise galactose which may be caused by a deficiency of any of the following enzymes: (1) Galactose-1 phosphate uridyl transferase (most common)\n\n\nUDP-galactose-4-epimerase\nGalactokinase\nThe defect in galactose metabolism results in accumulation of galactose-1-phosphate and galactical that are thought to have direct toxic effect on the liver and other organs.\n\nClinical features\n\n\nInfant appears normal at birth, however, becomes symptomatic a few days to weeks after initiating galactose containing feeds.\nDue to the accumulation of galactitol, damage to nerve tissue and liver occurs which causes:-\n\n\nHepatic parenchymal disease- jaundice, hepatomegaly and ascites\nMental retardation\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0 \xa0\nVitreous haemorrhage\xa0\nAcidosis\xa0\xa0\nCataract\nSeizures\xa0\xa0\xa0\nSplenomegaly\xa0\xa0\xa0 \xa0\nHypoglycemia \xa0 \xa0 \xa0 \xa0 \xa0\n\n\nThe accompanying GI symptoms are poor feedings, vomiting and diarrhea.\nFanconi syndrome (Aminoacidiuria, protein aria, phosphaturia) may occur.\n\nDiagnosis\n\nUrine shows reducing sugar which can be detected by\n\n\nBenedicts reagent\nGlucose oxidase method\n\n\nThe confirmatory diagnosis is made by the enzyme assay.', 'role': 'assistant'}]