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What is A 4 year old boy, with three days history of upper respiratory tract infection presents with stridor, which decreases on lying down. What is the most probable diagnosis? and explain in detail?
Prodromal symptoms of upper respiratory tract infection preceding sings of respiratory tract obstruction is characteristic of croup. Ref: Nelson 17th Edition, Page 1405;1406,14; Respiratory Care: Principles And Practice By Dean Hess, Neil MacIntyre, Shelley Mishoe, William Galvin, 2011, Page 1019.