Merck Manual

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Alan G. Cheng

, MD, Stanford University

Reviewed/Revised Mar 2022 | Modified Sep 2022
Topic Resources

Epiglottitis is a rapidly progressive bacterial infection of the epiglottis and surrounding tissues that may lead to sudden respiratory obstruction and death. Symptoms include severe sore throat, dysphagia, high fever, drooling, and inspiratory stridor. Diagnosis requires direct visualization of the supraglottic structures, which is not to be done until full respiratory support is available. Treatment includes airway protection and antibiotics.

Epiglottitis used to primarily affect children and usually was caused by Haemophilus influenzae type B. Now, because of widespread vaccination, it has been almost eradicated in children (more cases occur in adults). Causal organisms in children and adults include Streptococcus pneumoniae, Staphylococcus aureus, nontypeable H. influenzae, Haemophilus parainfluenzae, beta-hemolytic streptococci, Branhamella catarrhalis, and Klebsiella pneumoniae. H. influenzae type B is still a cause in adults and unvaccinated children.

Bacteria that have colonized the nasopharynx spread locally to cause supraglottic cellulitis with marked inflammation of the epiglottis, vallecula, aryepiglottic folds, arytenoids, and laryngeal ventricles. With H. influenzae type B, infection may spread hematogenously.

The inflamed supraglottic structures mechanically obstruct the airway, increasing the work of breathing, ultimately causing respiratory failure. Clearance of inflammatory secretions is also impaired.

Symptoms and Signs of Epiglottitis

In children with epiglottitis, sore throat, odynophagia, and dysphagia develop abruptly, often with no visible oropharyngeal inflammation. Fatal asphyxia may occur within a few hours of onset. Drooling is very common. Additionally, the child has signs of toxicity (poor or absent eye contact, cyanosis, irritability, inability to be consoled or distracted) and is febrile and anxious. Dyspnea, tachypnea, and inspiratory stridor may be present, often causing the child to sit upright, lean forward, and hyperextend the neck with the jaw thrust forward and mouth open in an effort to enhance air exchange (tripod position). Relinquishing this position may herald respiratory failure. Suprasternal, supraclavicular, and subcostal inspiratory retractions may be present.

In adults, symptoms are similar to those of children, including sore throat, fever, dysphagia, and drooling, but peak symptoms usually take > 24 hours to develop. Because of the larger diameter of the adult airway, obstruction is less common and less fulminant. Often, there is no visible oropharyngeal inflammation. However, severe throat pain with a normal-appearing pharynx raises suspicion of epiglottitis. A delay in diagnosis and treatment increases the risk of airway obstruction and death.

Diagnosis of Epiglottitis

  • Direct inspection (typically in operating room)

  • X-ray in milder cases with low suspicion

Epiglottitis is suspected in patients with severe sore throat and no pharyngitis and also in patients with sore throat and inspiratory stridor. Stridor in children may also result from croup Croup Croup is acute inflammation of the upper and lower respiratory tracts most commonly caused by parainfluenza virus type 1 infection. It is characterized by a brassy, barking cough and inspiratory... read more Croup (viral laryngotracheal bronchitis—see table Differentiating Epiglottitis From Croup Differentiating Epiglottitis From Croup Differentiating Epiglottitis From Croup ), bacterial tracheitis, and airway foreign body. The tripod position may also occur with peritonsillar or retropharyngeal abscess.


The patient is hospitalized if epiglottitis is suspected. Diagnosis requires direct examination, usually with flexible fiberoptic laryngoscopy. (CAUTION: Examination of the pharynx and larynx may precipitate complete respiratory obstruction in children, and the pharynx and larynx should not be directly examined except in the operating room, where the most advanced airway intervention is available.) Although plain x-rays may be helpful, they are not highly accurate (1 Diagnosis reference Epiglottitis is a rapidly progressive bacterial infection of the epiglottis and surrounding tissues that may lead to sudden respiratory obstruction and death. Symptoms include severe sore throat... read more Diagnosis reference ), and a child with stridor should not be transported to the x-ray suite. Direct laryngoscopy that reveals a beefy-red, stiff, edematous epiglottis is diagnostic. Cultures from the supraglottic tissues and blood can then be taken to search for the causative organism.

Adults may, in some cases, safely undergo flexible fiberoptic laryngoscopy.

Epiglottitis and Subglottic Croup

Pearls & Pitfalls

  • Examination of the pharynx or larynx in children with epiglottitis and stridor may precipitate complete airway obstruction.

Diagnosis reference

Treatment of Epiglottitis

  • Airway

  • Antibiotics (eg, ceftriaxone)

In children with stridor, any intervention that could be upsetting (and thus could trigger airway obstruction) should be avoided until an airway is established. In children with epiglottitis, the airway must be secured immediately. Securing the airway can be quite difficult and should, if possible, be done by experienced personnel in the operating room. An endotracheal tube is usually required until the patient has been stabilized for 24 to 48 hours (usual total intubation time is < 60 hours for both children and adults). Alternatively, a tracheotomy is done. If respiratory arrest occurs before an airway is established, bag-mask ventilation may be a life-saving temporary measure. For emergency care of children with epiglottitis, each institution should have a protocol that involves critical care, otolaryngology, anesthesia, and pediatrics.

Adults whose airway is severely obstructed can be endotracheally intubated during flexible fiberoptic laryngoscopy. Other adults may not require immediate intubation but should be observed for airway compromise in an intensive care unit with an intubation set and cricothyrotomy tray at the bedside.

A beta-lactamase–resistant antibiotic, such as ceftriaxone 50 to 75 mg/kg IV once/day (maximum 2 g), should be used empirically, pending culture and sensitivity test results.

Epiglottitis caused by H. influenzae type B can be effectively prevented with the H. influenzae type B (HiB) conjugate vaccine.

Key Points

  • The incidence of epiglottitis has decreased significantly, particularly in children, because of widespread vaccination against the most common cause, Haemophilus influenzae type B.

  • Stridor, as well as sore throat with a normal-appearing pharynx, are important clues.

  • Examination of the pharynx or larynx in children with epiglottitis and stridor may precipitate complete airway obstruction.

  • If the diagnosis is suspected, do flexible fiberoptic laryngoscopy in the operating room; reserve imaging studies for cases with very low suspicion.

  • Children typically should have their airway secured by tracheal intubation; adults often can be observed for signs of airway compromise.

  • Give a beta-lactamase–resistant antibiotic, such as ceftriaxone.

Drugs Mentioned In This Article

Drug Name Select Trade
Ceftrisol Plus, Rocephin
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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