<prompt> A child is brought to the pediatric OPD with fever of 24 hours duration. History reveals 3 episodes of chest infection and passage of foul smelling stools. The most probable diagnosis is:Cystic fibrosisMaple syrup urine diseaseBilirubin conjugation defectCriggler Najar syndrome  <response>: a. Cystic fibrosisRef: Nelsons 20e p 2098-2112, Ghai 8e p 393High grade fever and chest infection along with passage of foul smelling stools suggests systemic disease.In cystic fibrosis because of pancreatic exocrine insufficiency, foul smelling stool is common. 