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 premature infant is born with a patent ductus arteriosus. Its closure can be stimulated by administration of – \nSelect and explain. \nA. Prostaglandin analogue, B. Estrogen, C. Anti-estrogen compounds, D. Prostaglandin inhibitors', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Management of PDA\n\nAfter birth ductus arieriosus constricts within a few hours producing functional closure.\nPermanent anatomic closure follows in the next 10-21 days due to extensive intimal thickening.\nThe mechanism producing the initial constriction is not completely understood, but the increase in arterial 02 tension plays an important role.\nOne more factor which helps in closure of the ductus arteriosus is the decrease in concentration of prostaglandins at the time of birth\nIn the intrauterine period the concentration of prostaglandin PGF2 a is very high. This prostaglandin has a vasodilatory effect which keeps the ductus open.\nThe synthesis of these vasodilator is inhibited at birth by the inhibition of the enzyme cycloxygenase at birth.\nCycloxygenase is an important enzyme in the synthetic pathway of prostaglandin.\nIn many premature infants the ductus fail to close spontaneously. In these cases the closure can be produced by infusion of drugs that inhibit cyclooxygenase.\nIndomethacin is a potent inhibitor of prostaglandin synthesis. It inhibits prostaglandin synthesis by inhibiting the enzyme cyclooxygenase. \nIndomethacin is routinely used to close the PI A in premature infants, it does not close the P I.A of full term\xa0 infants or children. The success of indomethacin therapy is as high as 80-90% in premature infants with birth\xa0 weight over 1200 g. \nIf indomethacin is not successful and the ductus remains hemodynamically significant, surgical ligation should be performed without hesitation.\nRecent studies from Europe indicate that ibuprofen may be as effective as indomethacin for the medical closure of pretenn PDA.', 'role': 'assistant'}]