Practice Essentials
Chronic laryngitis is a current topic of interest, primarily because of newly identified etiopathogenetic factors related to the change in the quality of environmental pollutants and toxic products found in workplaces. The continuous evolution of such factors constitutes a challenge for medical experts, who must update their knowledge of new toxic/irritative materials being used by the industrial market. The need to implement strategies that recognize the deleterious effects on the human body and to use necessary corrective therapies represents a very active research field. Symptoms of chronic laryngitis can be present in otherwise healthy people.
View Image | Illustration of the larynx. |
Diagnosis
Laboratory studies in chronic laryngitis include the following:
Complete blood cell count with differential if an infection is suspected
Sputum cultures and sensitivities for bacteria, fungi, and viruses
Swab of the laryngeal mucosa, culture and sensitivities for bacteria, fungi, and viruses
Serologic markers for autoimmune disorders
Studies for tuberculosis and syphilis when such conditions are being considered
Imaging studies include the following:
Lateral plain neck radiograph
Chest radiograph
Computed tomography (CT) scanning and magnetic resonance imaging (MRI)
Barium swallow studies, double-contrast upper gastrointestinal (GI) series, manometry
Videostrobe
Skin tests can be performed if allergies are suspected, as can 24-hour pH monitoring if gastroesophageal reflux disease (GERD) is in the differential diagnosis.
The larynx can be directly examined with a flexible fiberoptic nasopharyngolaryngoscope. Direct laryngoscopy with a rigid laryngoscope (under general anesthesia) may be required for a detailed laryngeal inspection and may help obtain tissue for biopsy, cultures, and smears to identify the presence of organisms. Undertake this examination when noninvasive studies fail.
Accomplish a thorough evaluation of the aerodigestive tract, including bronchoscopy and esophagoscopy, when indicated. Stroboscopic examination may help to differentiate mucosal stiffness secondary to epithelial hyperplasia that may be caused by chronic inflammation.
Management
Medication therapies directed mainly against the causative agents vary on a case-by-case basis. With GERD, H2-receptor antagonists, proton pump inhibitors, and prokinetics are the main classes of drugs used.
Supportive measures include the following:
Hydration with about 2 liters of fluid intake per day
Steam inhalation or room humidifier
Avoidance of pollutant or irritative/toxic substances
Identification and avoidance of environmental and occupational sensitizers - Limitation of exposure or change in the work environment if noxious fumes and organic solvents are responsible; avoidance of cigarette smoking, even secondhand smoke
From a therapeutic standpoint, the following procedures may be indicated:
Reduction of stenosis is indicated if infiltrative processes or conditions, such as amyloidosis, Wegener granulomatosis, rheumatoid arthritis, or systemic lupus erythematous, have significantly narrowed the lumen of the larynx; aggressive surgical intervention may be required
Exophytic mass removal by surgical means
Laser vaporization
Laparoscopic antireflux surgery, using the Nissen fundoplication technique, has shown appreciable results in the treatment of GERD
Pathophysiology
Chronic laryngitis refers to an inflammatory process that determines irreversible alterations of the laryngeal mucosa. Reactive and reparative processes of the larynx represent the main pathogenetic factor, which can persist even when the causative stimulus ends. Depending on the causes, the pattern of changes can be very different. Inflammation, edema, hyperemia, and infiltration and proliferation of the mucosa can represent different levels of response to insults.
The inflammatory process damages the ciliated epithelium of the larynx, particularly in the posterior wall. This impairs the important function of moving the mucous flow out of the tracheobronchial tree. When the ciliary beating motion of the epithelium is impaired, the resultant mucous stasis on the posterior wall of the larynx and around the vocal cords provokes a reactive cough. Mucous across the vocal cords may manifest with laryngospasm. Significant changes may arise in the vocal cord epithelium in the form of hyperkeratosis, dyskeratosis, parakeratosis, acanthosis, and cellular atypia.
Epidemiology
Frequency
United States
The authors found no data regarding precise frequency. Because chronic laryngitis is usually part of a more complex disease, it is probably underreported.
Mortality/Morbidity
Chronic laryngitis presents a frustrating treatment problem. Voice loss, chronic cough, and airway obstruction, respectively, are the most likely complications. An association with cancer of the larynx is unclear. Mortality is obviously related to the main disease with which chronic laryngitis is associated.
Race
The condition apparently affects all races equally.
Sex
Traditionally, men have been mostly affected. In recent reports, a 2:1 male predominance still exists; however, the trend is changing, probably because of more women smoking cigarettes and their increasing involvement in work activities in toxic environments.
Age
Adults in the sixth decade of life are mainly affected. Neonates and infants share similar risk factors with adults for developing chronic laryngitis. Additionally, various congenital lesions of the larynx may present with voice changes.
Causes
Cigarette smoke is chronically irritating to the laryngeal mucosa. At the extreme, it can provoke cancer.
Ethanol contains many impurities, such as mycotoxins, tannins, aldehydes, and pesticides, which may cause cancer, either by direct contact with the mucosa or through a systemic effect, or may act as an irritant.
Gastroesophageal reflux disease
Chronic laryngitis associated with GERD is particularly important. The irritant is the gastric content, and the most significant part of the injury occurs at night when patients lie down.
The posterior wall of the larynx is mainly involved in the common and mild forms of GERD, although the process can involve any part of the upper respiratory tract epithelium. Diagnosis can be made after excluding other causes and after confirming the condition with appropriate pH studies. Reflux from any cause can elicit chronic laryngitis.
Infections
The bacterium most commonly isolated in chronic infectious laryngitis is Staphylococcus aureus. Haemophilus influenzae and pneumococcal species may complicate the course of viral laryngitis.
In a retrospective study of 15 patients with infectious laryngitis, by Thomas et al, cultures revealed the presence of methicillin-sensitive Staphylococcus aureus, methicillin-resistant S aureus, Pseudomonas aeruginosa, and Serratia marcescens, along with normal respiratory flora.[3] A study by Carpenter and Kendall reported that of 23 patients with chronic bacterial laryngitis, seven (30.4%) were found to be infected with methicillin-resistant Staphylococcus aureus.[4]
Tuberculosis, caused by infection with the tubercle bacillus Mycobacterium tuberculosis hominis, was a common disease of the larynx. Overall incidence has declined. The hematogenous route and the infected sputum from pulmonary tuberculosis are the most likely sources of infection.
Leprosy, caused by infection with Mycobacterium leprae (also known as Hansen bacillus): This acid-fast bacilli has a propensity to invade nerves and to affect the larynx, primarily the epiglottis. The portal of entry is thought to be the nasal mucosa; hence, nasal perforation is common. The larynx is the second most commonly affected part.
Syphilis, caused by the spiral bacterium Treponema pallidum: Syphilis has 3 stages of disease, as follows: primary, in which the chancre is the main clinical finding; secondary, in which systemic and cutaneous involvement predominate; and tertiary, in which destructive noninfectious processes are prevalent. The larynx is involved in the secondary and tertiary stages. Laryngeal involvement in congenital syphilis is similar to that seen in secondary syphilis.
Rhinoscleroma is caused by the gram-negative rod Klebsiella rhinoscleromatis.
Actinomycosis, a granulomatous disease caused by the anaerobic gram-positive bacteria Actinomyces israelii, is part of the normal oropharyngeal flora and may manifest as an abscess.
Viruses, although most important in determining viral laryngitis, play a minor role in the etiology of chronic laryngitis.
Fungal infections are very common. Patients who are immunocompromised, either naturally or as a consequence of a pharmacologic treatment, are mainly affected. Fungi can be found on the mucosal surface of the larynx, or they can invade it. Immunosuppression can be congenital or acquired and can be derived from AIDS. Immunosuppression can be drug induced (eg, antibiotics, steroids, chemotherapeutic agents) or secondary to radiation therapy.
A case study and literature review by Worrall et al found that out of 29 cases of laryngeal cryptococcosis, each of which involved persistent or progressive hoarseness, 28% of patients were immunocompromised, while, prior to infection, 67% of the immunocompetent patients had used nebulized or inhaled corticosteroids.[5]
Candidal laryngitis almost invariably manifests with pharyngitis due to superficial colonization of the mucosa; the oral cavity is often involved. When a patient takes inhaled steroids, the larynx can be the only site involved.
Invasive infections can occur as with blastomycosis and histoplasmosis, which are endemic conditions in certain areas of the world. In the United States, Histoplasma capsulatum and Blastomyces dermatitis are prevalent in the Ohio River area (histoplasmosis) and in the southwestern United States (blastomycosis).
Paracoccidioidomycosis, coccidiosis, aspergillosis, and rhinosporidiosis represent other fungal organisms that are less frequently involved in the development of chronic fungal laryngitis.
Although no endemic laryngeal parasitic infections exist in the United States, sporadic cases may affect foreign travelers with local organisms and with leishmaniasis and sporotrichosis.
Kania et al reported of a primary MALT lymphoma of the larynx associated with extraesophageal reflux, chronic laryngitis, and gastric Helicobacter pylori infection.[6]
Other
Voice abuse can be pertinent to professional singers and to occasional shouters. Lesions can range from simple edema, in the occasional abuser, to hyperplastic reactions if the stimuli persist over time.
Allergic responses of immediate or delayed hypersensitivity types can cause chronic laryngitis.[7] Although the authors found no data quantifying the exact number of people affected, current thought seems to indicate an increasing prevalence.
Environmental factors, such as dust, fumes, chemicals, and toxins, can cause this condition.
Chronic laryngitis has been diagnosed in many people who 20 years earlier inhaled sulfur mustard, an alkylating warfare agent used in the Iran-Iraq war (1983-88).[8]
Systemic diseases
Systemic diseases, mostly autoimmune, may cause chronic laryngitis. They include the following:
Wegener granulomatosis: Inflammation and granulomas may affect the larynx. It can be localized, involving only the upper airways. Clinically, patients may present with hemoptysis and stridor and upper airway stenosis of unexplained etiology, depending on the degree of involvement. Biopsy is not always diagnostic.
Amyloidosis: Amyloid deposition can involve the larynx and the upper aerodigestive tract. Patients may present with symptoms of upper airway obstruction, dyspnea, and hoarseness. The amyloid can cause vascular fragility and consequent bleeding.
Relapsing polychondritis: Adults in the fifth decade are mostly affected. They may present with hoarseness, airway obstruction, and pain. Clinically, the larynx can be tender. Symptoms and signs are secondary to inflammation and swelling of the glottic and subglottic areas. Repeated inflammation may result in tracheomalacia.
Cutaneous diseases
The larynx and the skin share similar microcharacteristics and macrocharacteristics. Pemphigus, Stevens-Johnson syndrome, systemic lupus erythematous, and epidermolysis bullosa are among the most important conditions.
Systemic lupus erythematous may manifest with laryngeal ulceration, erythema, and edema. Rheumatoid type nodules and necrotizing vasculitis can be seen.
With rheumatoid arthritis, the joints and the mucosa of the larynx can be affected to the same extent that other parts of the body are affected.
Neurologic causes
Neurologic causes may contribute to chronic laryngitis. Two branches of the vagus nerve supply the larynx, the superior laryngeal nerve and the recurrent laryngeal nerve (RLN). Alterations of the nerve supply and the larynx muscles determine abnormal motility of the various components of the larynx with resultant irritation.
Possible outcomes include the following:
Unilateral paralysis of the vagus nerve or the RLN
Bilateral abductor paralysis, in almost all cases caused by extensive thyroid surgery, with injury to the RLN
Superior laryngeal nerve paralysis, most often secondary to thyroidectomy or supraglottic laryngectomy
Additional causes
Spastic dysphonia is a discrete vocal disorder characterized by strained, choked vocal attacks (laryngeal stuttering). The onset usually follows a stressful period in middle life. This condition is probably a vocal expression of psychoneurotic behavior or a CNS and/or proprioceptive disorder of the larynx.
Vocal folds atrophy and lose tension with age, causing changes in phonation. Loss of thyroarytenoid ligament elasticity results in breathiness and loss of breath support because of bowed vocal folds.
Muscular disorders may contribute to chronic laryngitis. Weakness of the larynx and the pharynx is present in one third of patients with myasthenia gravis.
Laryngitis can be secondary to pellagra.[9]
Procedures
The larynx can be directly examined with a flexible fiberoptic nasopharyngolaryngoscope. Direct laryngoscopy with a rigid laryngoscope (under general anesthesia) may be required for a detailed laryngeal inspection and may help obtain tissue for biopsy, cultures, and smears to identify the presence of organisms. Undertake this examination when noninvasive studies fail.
Accomplish a thorough evaluation of the aerodigestive tract, including bronchoscopy and esophagoscopy, when indicated. Stroboscopic examination may help to differentiate mucosal stiffness secondary to epithelial hyperplasia that may be caused by chronic inflammation. Endoscopic removal of polyps and lysis of adhesions can be surgically accomplished.
A study by Witt et al suggested that hue and texture analysis of laryngoscopic images can be used to diagnose laryngopharyngeal reflux (LPR) in patients with chronic laryngitis. The study, which included 20 patients with LPR and 42 controls, used hue calculation and two-dimensional Gabor filtering to evaluate color and texture features of the images, with 80.5% classification accuracy found when hue and texture were assessed together.[10]
Medical Care
Medication therapies directed mainly against the causative agents vary on a case-by-case basis. With GERD, H2-receptor antagonists, proton pump inhibitors, and prokinetics are the main classes of drugs used. A study failed to provide evidence to support treatment with esomeprazole 40 mg twice a day for 16 weeks compared with placebo for chronic posterior laryngitis (CPL).[12]
A study by Mirić et al suggested that in patients with GERD and chronic laryngitis, gas diffusion capacity should be controlled, even when lung function is normal. The study included 30 children with chronic or recurrent laryngitis who tested positive for GERD. Increases in reflux indexes correlated with decreases in values for single-breath diffusing capacity of the lung for carbon monoxide (DLCO); ie, the odds for a significant reduction in the DLCO increased by 3.9% and 5.5% for each unit change in the Johnson-DeMeester and Boix-Ochoa scores, respectively.[13]
Supportive measures include the following:
Hydration with about 2 liters of fluid intake per day
Steam inhalation or room humidifier
Avoidance of pollutant or irritative/toxic substances
Identification and avoidance of environmental and occupational sensitizers: Limitation of exposure or change in the work environment if noxious fumes and organic solvents are responsible; avoidance of cigarette smoking, even secondhand smoke
Author
Stefano Berliti, MD, FACP, Physician, Department of Medicine, Conquest Hospital, East Sussex NHS Trust, UK
Disclosure: Nothing to disclose.
Coauthor(s)
Barry L Wenig, MD, MPH, FACS, Professor, Department of Otolaryngology-Head and Neck Surgery, Feinberg School of Medicine, Northwestern University; Chief, Division of Otolaryngology-Head and Neck Surgery, Evanston Northwestern Healthcare
Disclosure: Nothing to disclose.
Michael Omidi, MD, FACS,
Disclosure: Nothing to disclose.
Specialty Editors
Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Robert M Kellman, MD, Professor and Chair, Department of Otolaryngology and Communication Sciences, State University of New York Upstate Medical University
Disclosure: Nothing to disclose.
Chief Editor
Arlen D Meyers, MD, MBA, Professor of Otolaryngology, Dentistry, and Engineering, University of Colorado School of Medicine
Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Cerescan;RxRevu;Cliexa;The Physicians Edge;Sync-n-Scale;mCharts<br/>Received income in an amount equal to or greater than $250 from: The Physicians Edge, Cliexa<br/> Received stock from RxRevu; Received ownership interest from Cerescan for consulting; .
Additional Contributors
John M Truelson, MD, FACS, Chairman, Division of Head and Neck Surgery, Associate Professor, Department of Otorhinolaryngology, University of Texas Southwestern Medical Center at Dallas
Disclosure: Nothing to disclose.
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