Laryngitis

Laryngitis is inflammation of the larynx. The main symptom is an altered voice (e.g., hoarseness). Acute laryngitis is commonly caused by viral upper respiratory tract infection (URTI) or vocal strain and is typically self-limited, with complete resolution within three weeks. Laryngitis is considered chronic if symptoms last longer than three weeks. Common causes of chronic laryngitis include gastroesophageal or laryngopharyngeal reflux, smoking, and postnasal drip. Acute laryngitis with no red flags of hoarseness is diagnosed clinically without any further evaluation, especially if the patient's history is consistent with viral URTI or vocal strain. Individuals with red flags of any duration and individuals with dysphonia and/or hoarseness that lasts for four weeks or longer require laryngoscopy to evaluate for alternative diagnoses. Further evaluation is guided by history, physical examination, and laryngoscopy. Laryngitis is treated with supportive measures (e.g., voice rest, hydration, and avoidance of airway irritants) and, in the case of chronic laryngitis, treatment of the underlying cause.

• Acute laryngitis: inflammation of the larynx, which contains the vocal fold mucosa, for < 3 weeks
• Chronic laryngitis: inflammation of the larynx for ≥ 3 weeks

Etiology of acute laryngitis ^[1][2]

• Viral URTIs (most common cause) ^[3]
• Bacterial URTIs
  • Superinfections may occur following a viral infection.
  • Laryngeal diphtheria (rare) ^[3]
• Vocal strain, e.g., from coughing or overuse of vocal cords

Etiology of chronic laryngitis ^[1]

• Most common: Gastroesophageal reflux disease (GERD) or laryngopharyngeal reflux (LPR) ^[4]
• Smoking
• Adverse effects of certain medications ^[1]
• Postnasal drip, e.g., from recurrent URTIs or allergic rhinitis
• Chronic infections of the larynx (e.g., fungal infections, tuberculosis) ^[5][6]
• Systemic autoimmune diseases (rare) ^[3]
  • Granulomatosis with polyangiitis ^[7]
  • Rheumatoid arthritis
  • Sarcoidosis

• Voice changes: dysphonia, hoarseness, loss of voice ^[5][6]
• Sore or dry throat ^[8]
• Additional symptoms depend on the underlying cause. ^[1]
  • Fever: viral URTIs, bacterial infections ^[3]
  • Cough: viral URTIs, allergic rhinitis, airway irritants
  • Enlarged lymph nodes: infection
  • Odynophagia: GERD, LPR, URTI
  • Throat clearing: postnasal drip, GERD, LPR, inhaled corticosteroids
  • Globus sensation: GERD, LPR ^[3][9]

Approach

• Initiate immediate airway management in patients with clinical features of airway obstruction. ^[3]
• Obtain a thorough medical history and physical examination. ^[3][6]
• If history and/or physical examination suggest a specific underlying cause, order appropriate tests, as indicated.
• Urgently refer patients to otolaryngology for laryngoscopy for any of the following:
  • Red flags of hoarseness
  • Hoarseness and/or dysphonia ≥ 4 weeks
  • Professional voice users, e.g., professional singers, teachers ^[6]
• Recommend supportive care for laryngitis to all patients.
• Initiate management of acute laryngitis or management of chronic laryngitis as appropriate.
• Follow-up; if symptoms do not improve, consider:
  • Referral to otolaryngology
  • Diagnostic studies for laryngitis
  • Reevaluating for differential diagnoses of laryngitis

The majority of patients with acute laryngitis can be diagnosed clinically and do not require diagnostic studies. ^[6]

Supportive care for laryngitis

• Vocal rest: Avoid shouting, using a loud voice, and forced whispering.
• Analgesia as needed
• Mucosal hydration
  • Drink water.
  • Increase humidity (e.g., cool mist humidifier) in dry environments.
  • Avoid medications that dry the airway mucosa. ^[6]
• Avoid exposure to airway irritants, e.g., via smoking cessation.

Management of acute laryngitis ^[6]

• Acute laryngitis is primarily a clinical diagnosis; consider diagnostic studies only: ^[6]
  • If certain bacterial infections are suspected ^[5][6][10]
  • To exclude differential diagnoses of laryngitis
• Typically self-limited and resolves in 1–3 weeks with supportive care only ^[5][6][10]
• Follow up within a few weeks to ensure resolution.

Antibiotics are ineffective in improving symptoms in adults with acute laryngitis. ^[10]

Management of chronic laryngitis ^[6]

• Treat the underlying cause.
• Consider changing offending medications (e.g., ACE inhibitors, inhaled corticosteroids).
• For all other causes of chronic laryngitis, confirm the diagnosis before initiating treatment, e.g.:
  • Suspected GERD or LPR:
    • Perform laryngoscopy to look for evidence of reflux.
    • Start GERD treatment with acid suppression medications.
  • Allergic rhinitis:
    • Perform diagnostics for allergic rhinitis.
    • If diagnosis is confirmed, initiate management of allergic rhinitis.
• Consider referral to speech pathology for adjunctive voice therapy.
• Refer patients with hoarseness and/or dysphonia lasting ≥ 4 weeks for laryngoscopy.
• Reassess response to treatment at appropriate intervals.

Do not initiate treatment with proton pump inhibitors, antibiotics, or corticosteroids without first confirming the cause of chronic laryngitis. ^[6]

Diagnostic studies for laryngitis

Diagnostic studies are usually performed by otolaryngology.

Laryngoscopy ^[1]

• Laryngoscopy is used to assess for characteristic changes of laryngitis.
• Biopsy can be performed on lesions or for tissue culture. ^[11]
• Consider laryngeal swabs in chronic laryngitis. ^[11][12]
  • Minimally invasive and easy to obtain
  • High false negative rate ^[11]

Indications

• Red flags of hoarseness, e.g.: ^[6]
  • Signs of respiratory distress, dyspnea, and/or stridor
  • Laryngeal trauma, e.g., recent endotracheal intubation or surgery of the head, neck, or chest ^[6]
  • History of neck radiation ^[3]
  • Neck mass
  • History of tobacco use disorder
  • Neurological symptoms, e.g., dysarthria
  • Dysphagia
  • Unintentional weight loss
• Hoarseness and/or dysphonia lasting ≥ 4 weeks
• Hoarseness in professional voice users, e.g., professional singers, teachers ^[6]
• Suspected GERD or LPR
• Diagnostic uncertainty

Children with inspiratory stridor consistent with typical croup do not require laryngoscopy or referral to otolaryngology. ^[13]

Modalities

• Mirror laryngoscopy
• Fiberoptic laryngoscopy
• Direct laryngoscopy

Potential findings in laryngitis ^[9]

• Laryngeal inflammation with erythema and edema, including hyperemia of the inflamed vocal folds ^[1][5]
• Additional features include:
  • Mucus: in LPR, allergic rhinitis ^[14]
  • Pus: in bacterial infections ^[3]
  • Posterior commissure hypertrophy: in GERD and LPR
  • Ulcerations, nodules, and granulomas: in GERD, LPR, and chronic tuberculous laryngitis ^[3][5]
  • Cobblestone appearance of the posterior pharyngeal wall: in GERD, LPR, and allergic rhinitis ^[15]

Imaging ^[6][16]

• Indications
  • Inconclusive laryngoscopy
  • Laryngoscopy finding of vocal cord paralysis or laryngeal mass
• Modalities: contrast-enhanced CT or MRI ^[17][18]

• Upper airway foreign body aspiration ^[6]
• Trauma: endotracheal intubation, injury, hematoma
• Acute infection of: ^[5]
  • Subglottic structures: laryngotracheitis (croup)
  • Supraglottic structures: epiglottitis, pharyngitis
• Retropharyngeal abscess
• Inhalation injury
• Differential diagnoses of hoarseness:
  • Laryngeal cancer
  • Benign laryngeal lesions, e.g., polyp, cyst, laryngeal papillomatosis
  • Spasmodic dysphonia
  • Vocal fold paralysis
  • Neuromuscular and neurological diseases, e.g., Parkinson disease, myasthenia gravis
• See also “Differential diagnoses of stridor.”

The differential diagnoses listed here are not exhaustive.