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: Surgery
[{'content': "A new born presents with discharge of urine from the umbilicus for 3 days. Diagnosis is - \nSelect and explain. \nA. Meckel's diverticulum, B. Mesenteric cysts, C. Urachal fistula, D. Omphalocele", 'role': 'user'}, {'content': 'Answer: C \nExplanation: • A patent urachus seldom reveals itself until maturity or even old age.\n• This is because the contractions of the bladder commence at the apex of the organ and pass towards the base.\n• Because it opens into the apex of the bladder a patent urachus is closed temporarily during micturition and so the potential urinary stream from the bladder is cut off.\n• Thus, the fistula remains unobtrusive until a time when the organ is overfull, usually due to some form of obstruction.\nTreatment\n• Remove the obstruction\xa0in the lower urinary tract.\n• If the leak continues or a cyst develops in connection with the urachus: Umbilectomy and excision of the urachus', 'role': 'assistant'}]