<prompt> Most common cause of acute epiglottitis isHemophilus influenza type BPneumococcusStreptococcusStaphylococcus  <response>: It is an acute inflammatory condition confined to supraglottic structures i.e, epiglottis, aryepiglottic folds and arytenoids. There is marked oedema of these structures which may obstruct the airway. Aetiology It is a serious condition and affects children of 2-7 years of age but can also affect adults. Haemophilus influenzae B is the most common organism responsible for this condition in children. Ref: Textbook of diseases of ENT, PL Dhingra, 7th edition, pg no. 327 