Laryngitis

Aside from a hoarse-sounding voice, changes to pitch and volume may occur with laryngitis. Speakers may experience a lower or higher pitch than normal, depending on whether their vocal folds are swollen or stiff.[1][9] They may also have breathier voices, as more air flows through the space between the vocal folds (the glottis), quieter volume[10] and a reduced range.[1]

• Most acute cases of laryngitis are caused by viral infections,[1] the most common of which tend to be rhinovirus, influenza virus, parainfluenza virus, adenovirus, coronavirus, and RSV. In patients who have a compromised immune system, other viruses such as herpes, HIV and coxsackievirus may also be potential causes.

• This is another major cause of acute laryngitis, and may develop in conjunction with or due to a viral infection.[1] Common bacterial strains are; group A streptococcus, Streptococcus pneumoniae, C. diphtheriae, M. catarrhalis, Haemophilus influenzae, Bordetella pertussis, Bacillus anthracis, and M. tuberculosis. In developing countries, more unusual bacterial causes may occur such as mycobacterial and syphilitic, though these may occur in developed nations as well.[1]

• Laryngitis caused by fungal infection is common but not frequently diagnosed according to a review by BMJ and can account for up to 10% of acute laryngitis cases.[1] Patients with both functioning and impaired immune systems can develop fungal laryngitis, which may develop as a result of recent antibiotic or inhaled corticosteroids use.[1] Certain strains of fungi that may cause laryngitis include; Histoplasma, Blastomyces, Candida (especially in immunocompromised persons), and Cryptococcus and Coccidioides.

• Often due to excessive use of the vocal folds such as excessive yelling, screaming, or singing. Though this often results in damage to the outer layers of the vocal folds, the subsequent healing may lead to changes in the physiology of the folds.[1] Another potential cause of inflammation may be overuse of the vocal cords.^{[5] [6] [7] [8] [9]} Laryngeal trauma, including iatrogenic (caused by endotracheal intubation), can also result in inflammation of the vocal cords.[11]

• Findings are unclear as to whether asthma may cause symptoms commonly associated with laryngitis.[1] Some researchers have posited that allergic causes of laryngitis are often misdiagnosed as being the result of acid reflux.[12]

• One possible explanation of chronic laryngitis is that inflammation is caused by gastro-oesophageal reflux, which causes subsequent irritation of the vocal folds.[13]

• Approximately between 30–75% of persons with rheumatoid arthritis report symptoms of laryngitis.[1]
• Symptoms of laryngitis are present in only 0.5–5% of people that have sarcoidosis.[1] According to a meta-analysis by Silva et al. (2007), this disease is often an uncommon cause of laryngeal symptoms and is frequently misdiagnosed as another voice disorder.[14]

The larynx itself will often show erythema (reddening) and edema (swelling). This can be seen with laryngoscopy or stroboscopy (method depends on the type of laryngitis).[7]^:108 Stroboscopy may be relatively normal or may reveal asymmetry, aperiodicity, and reduced mucosal wave patterns.[16]

Other features of the laryngeal tissues may include

• Redness of the laryngeal tissues (acute)
• Dilated blood vessels (acute)
• Thick, yet dry laryngal tissue (chronic)
• Stiff vocal folds
• Sticky secretions between the vocal folds and nearby structures (the interarytenoid region)

Some signs and symptoms indicate the need for early referral.[1] These include

• Difficulty swallowing
• Vocal stridor
• Ear pain
• Recent weight loss
• History of smoking
• Current or recent radiotherapy treatment (in the neck region)
• Recent neck surgery or surgery involving endotracheal tubing
• Person is a professional voice user (teacher, singer, actor, call center worker, and so on)

• Acute epiglottitis: This is more likely in those with stridor, drooling, and painful or trouble swallowing.[1]
• Spasmodic dysphonia[16]
• Reflux laryngitis[16]
• Chronic allergic laryngitis[16]
• Neoplasm[16]
• Croup: This presents with a barking cough, hoarseness of voice, and inspiratory stridor.[15]

In general, acute laryngitis treatment involves vocal hygiene, painkillers (analgesics), humidification, and antibiotics.[1][5]

The suggested treatment for viral laryngitis involves vocal rest, pain medication, and mucolytics for frequent coughing.[7] Home remedies such as tea and honey may also be helpful.[1] Antibiotics are not used for treatment of viral laryngitis.[1][17]

Antibiotics may be prescribed for bacterial laryngitis, especially when symptoms of upper respiratory infection are present.[7] However, the use of antibiotics is highly debated for acute laryngitis. This relates to issues of effectiveness, side effects, cost, and possibility of antibiotic resistance patterns. Overall, antibiotics do not appear to be very effective in the treatment of acute laryngitis.[5]

In severe cases of bacterial laryngitis, such as supraglottitis or epiglottitis, there is a higher risk of the airway becoming blocked.[7] An urgent referral should be made to manage the airway.[1] Treatment may involve humidification, corticosteroids, intravenous antibiotics, and nebulised adrenaline.[7]

Fungal laryngitis can be treated with oral antifungal tablets and antifungal solutions.[1][7] These are typically used for up to three weeks and treatment may need to be repeated if the fungal infection returns.[7]

Laryngitis caused by excessive use or misuse of the voice can be managed though vocal hygiene measures.

Laryngopharyngeal reflux treatment primarily involves behavioural management and medication.[1][7] Behavioural management involves aspects such as

• Wearing loose clothing
• Eating smaller, more frequent meals
• Avoiding certain foods (e.g. caffeine, alcohol, spicy foods)[7]

Anti-reflux medications may be prescribed for patients with signs of chronic laryngitis and hoarse voice.[18] If anti-reflux treatment does not result in a decrease of symptoms, other possible causes should be examined.[1] Over-the-counter medications for neutralizing acids (antacids) and acid suppressants (H-2 blockers) may be used.[7] Antacids are often short-acting and may not be sufficient for treatment.[7] Proton pump inhibitors are an effective type of medication.[7] These should only be prescribed for a set period of time, after which the symptoms should be reviewed.[1] Proton pump inhibitors do not work for everyone. A physical reflux barrier (e.g. Gaviscon Liquid) may be more appropriate for some.[1] Antisecretory medications can have several side-effects.[1]

When appropriate, anti-reflux surgery may benefit some individuals.[1]

When treating allergic laryngitis, topical nasal steroids and immunotherapy have been found to be effective for allergic rhinitis.[7] Antihistamines may also be helpful, but can create a dryness in the larynx.[7] Inhaled steroids that are used for a long period can lead to problems with the larynx and voice.[7]

Mucous membrane pemphigoid may be managed with medication (cyclophosphamide and prednisolone).[1]

Sarcoidosis is typically treated with systemic corticosteroids. Less frequently used treatments include intralesional injections or laser resection.[1]

Acute laryngitis may persist, but will typically resolve on its own within two weeks.[1] Recovery is likely to be quick if the patient follows the treatment plan.[19] In viral laryngitis, symptoms can persist for an extended period, even when upper respiratory tract inflammation has been resolved.[17]

Laryngitis that continues for more than three weeks is considered chronic.[1] If laryngeal symptoms last for more than three weeks, a referral should be made for further examination, including direct laryngoscopy.[1] The prognosis for chronic laryngitis varies depending on the cause of the laryngitis.[19]