This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other hea diseases in children, Subject name: Pediatrics
[{'content': 'A two-month-old infant is brought to emergency depament with marked respiratory distress. On examination, the infant has cyanosis and bilateral crepitations. Hea rate is 180/min, respiratory rate 56/min and the liver span 7.5 cm. The child had repeated episodes of fever, cough and respiratory distress since the time of bih. Cardiovascular examination reveals a grade III ejection systolic murmur in left para-sternal area and the chest X-ray reveals cardiomegaly with a narrow base and plethoric lung fields. What is the most likely diagnosis? \nSelect and explain. \nA. Congenital methemoglobinemia, B. Transposition of great aeries, C. Cystic fibrosis, D. Tetralogy of Fallot', 'role': 'user'}, {'content': "Answer: B \nExplanation: - In the given case scenario, infant has features of hea failure, cyanosis with repeated episodes of pneumonia suggesting increased pulmonary blood flow. - These clinical features along with the chest X ray findings are suggestive of Transposition of great aeries. - ON X-RAY : 'Egg on side' or 'Egg on string' appearance is characteristic of transposition of great aeries Other options: Congenital methemoglobinemia: Inherited in autosomal recessive pattern Diagnosed by genetic testing/ blood tests CYSTIC FIBROSIS: Mutation in gene encoding for CFTR - Located on long arm of chromosome 7 Presents with recurrent bronchiolitis in infancy, recurrent lower resp tract infections, bronchiectasis, steatorrhea, pancreatitis & azoospermia Diagnosed by presence of typical phenotype/ family history & confirmed by high sweat chloride on atleast 2 occasions/ by identifying mutation in both copies of CFTR TOF: Doesn't present with cyanosis at bih. X-ray shows Boot shaped hea.", 'role': 'assistant'}]