Tonsils and Adenoids

After completing this article, readers should be able to:Almost every parent has a familiarity with tonsils and adenoids. They or their children may have had tonsillitis or sore throats, may snore,may have difficulty breathing, or may know someone who has undergone a tonsillectomy or adenoidectomy. Suspected tonsillar or adenoidal abnormalities prompt frequent visits to physicians. Because tonsils and adenoids are addressed so frequently,it is important to understand these structures, possible abnormalities and potential sequelae, and management options.“Tonsils” and “adenoids” are generic terms applied to the lymphatic tissues located within the oral cavity. In reality, they are part of a ring of lymphatic tissues around the nasopharynx and oropharynx at the entry point to the upper aerodigestive tract. Several separate structures form this ring, classically known as the Waldeyer ring. Adenoids or pharyngeal tonsils are the superior extent of the ring and are located within the nasopharynx. They are a diffuse or nodular collection of lymphoid tissue that forms a number of folds within the mucosa of the roof and posterior wall of the nasopharynx. The adenoids receive blood supply from branches of the external carotid artery. Venous drainage goes through the pharyngeal plexus into the internal jugular vein, and innervation originates from the glossopharyngeal and vagus nerves. Hypertrophy of the adenoids commonly results in snoring, rhinorrhea,or both; may cause otitis media or obstruction of the nasopharynx; and is associated with sinusitis. Hypertrophied adenoidal tissue may extend into the superolateral nasopharynx into the pharyngeal fossa(fossa of Rosenmuller) located immediately posterior to the eustachian tube orifice. This lymphatic tissue infrequently is referred to as Gerlach tonsils.The term “tonsils” most often refers to the palatine tonsils. The palatine tonsils are located on the posterolateral walls of the oropharynx,are surrounded by the tonsillar pillars (palatoglossus anterolaterally,palatopharyngeus posteromedially),and form the lateral component of the lymphatic ring. They usually are seen easily during an oral cavity examination and frequently are the site of infection or may cause upper airway obstruction if significantly enlarged. The palatine tonsils have a generous blood supply originating from the external carotid artery. The venous drainage is through a pericapsular plexus that ultimately drains into the internal jugular vein. The lesser palatine branch of the glossopharyngeal nerve provides innervation.The lymphatic ring is completed inferiorly by the lingual tonsils,which are located on the tongue base. They are a nonencapsulated nodular lymphatic aggregation of variable size. The blood supply is via the lingual branches of the external carotid artery, and innervation comes from the glossopharyngeal nerve.The lymphatic structures previously described have multiple folds or crypts. These irregularities increase the lymphatic surface area for direct antigenic stimulation. There often is a substantial difference between the pathogens located on the surface of the tonsil or adenoid and those that reside deep inside these folds of tissue. For this reason, superficial swab cultures may not yield the causative organism of an infection,which could lead to failure of medical treatment if the choice of antibiotic is based completely on a superficial swab.Recovery of an organism from a swab also does not indicate causality of a tonsillar or pharyngeal infection. Multiple organisms can infect tonsils, including aerobic and anaerobic bacteria, viruses, fungi, and parasites. The majority of pathologic isolates are common bacteria, and there is a close correlation between palatine tonsil and adenoid bacteriology. Group A streptococci are normal flora of the oropharynx and nasopharynx; 15% to 20% of children are colonized by this aerobic bacteria. However, these also may be infectious pathogens that require treatment. Other common isolates include Haemophilus influenzae,Staphylococcus aureus, S pneumoniae,and Morexella catarrhalis. A significant portion of children(approximately 40%) who have adenotonsillar disease will yield a beta-lactamase-producing bacteria,an important consideration when prescribing antibiotic therapy.Viral infections usually are mild and self-limiting and do not require specific treatment. Important causes of viral pharyngitis include adenovirus,influenza A, and herpes simplex(in adolescents). Several notable exceptions to the mild symptomatic viral course include infection with coxackievirus A, which causes painful vesicles and ulceration of the tonsils and oropharynx, and Epstein-Barr virus, which causes infectious mononucleosis. Epstein-Barr virus can cause tonsils and adenoids to enlarge rapidly, resulting in acute airway obstruction. Infections with fungi such as Candida sp are not uncommon, particularly among infants or immunocompromised children.The tonsils are secondary lymphatic structures formed by nodular collections of lymphatic tissue. They are part of the mucosa-associated lymphoid tissue system. Significant differences exist between the tonsils and other lymphatic structures. For example, tonsils do not possess afferent lymphatic channels, and they are not fully encapsulated. As noted previously, the irregular folds and crypts contained in the tonsils increase the surface area for antigenic stimulation. When an antigen contacts the surface of the tonsil, it stimulates B cells, which results in a lymphocytic migration to glandular sites where they differentiate into immunoglobulin (Ig)-producing cells. Most Ig production yields IgA,but IgG and IgM also are detectable in pharyngeal secretions, although in much lower quantities. IgA assists in preventing bacteria and viruses from adhering to pharyngeal mucosa. Children who have IgA deficiency cannot manifest an appropriate immunologic response and, therefore,are susceptible to recurrent infections and allergies. Tonsillectomy and adenoidectomy result in a detectable decrease of serum IgA and IgG, but the levels remain within the ranges of normal.Children who have adenotonsillar abnormalities present variably. Usually,those who have an infection have throat discomfort, odynophagia,tender cervical nodes, halitosis,or fever. The clinical examination may reveal erythematous and swollen tonsils, possibly with an exudate that can be patchy or completely cover the tonsil. A particularly heavy, gray, malodorous exudate is possible from an Epstein-Barr virus infection and should be considered in the differential diagnosis. Petechiae of the soft palate and tonsillar pillars are not uncommon. Dry mucous membranes and thick secretions may result from decreased oral intake. Adenoiditis causes nasal congestion,rhinorrhea, and sore throat with associated halitosis and may disrupt normal nasal breathing patterns. Recurrent or chronic infections lead to hypertrophy and enlargement of the adenotonsillar tissue.Acute streptococcal infections,including tonsillitis, that remain untreated may have consequences that range from mild to severe. Uncomplicated group A streptococcal infections may cause pharyngitis or pyoderma. More severe suppurative complications include otitis media, sinusitis, peritonsillar abscesses, or abscesses within the parapharyngeal and retropharyngeal spaces. Peritonsillar abscesses(“Quinsy tonsil”) may develop that result in significant oropharyngeal compromise, discomfort, and potential necessity for emergent surgical intervention. Cervical adenitis also may be noted. Severe nonsuppurative complications may include acute rheumatic fever with its associated arthritis and carditis or post-streptococcal glomerulonephritis. Toxin-mediated disease such as scarlet fever or toxic shock syndrome also occurs in children as well as immunemediated conditions such as IgA nephropathy, which may progress slowly to end-stage renal disease.Persistent significant adenotonsillar hypertrophy may lead to other pathologic conditions that have much more severe implications. Most commonly, adenotonsillar hypertrophy presents with snoring,mouth breathing, nasal congestion and rhinorrhea, mild dysphasia, or mild inspiratory stridor. Frequently these mild symptoms worsen when the child contracts an upper respiratory tract infection. Upper airway obstruction may cause a variety of breathing and sleep disorders that may lead to obstructive sleep apnea.The diagnosis of obstructive sleep apnea often is delayed in children. Children frequently maintain normal daytime activity in contrast to adults, who commonly present with complaints of fatigue and daytime somnolence. Pediatric manifestations usually are more subtle. Personality changes, irritability, and behavioral problems are common among children younger than 5 years of age.Older children often present with nocturnal changes, including fitful sleep, sleeping in strange positions with their necks extended, night sweats, or enuresis coupled with morning complaints of headache. Among infants, obstructive sleep apnea may be a functional cause of failure to thrive. Failure to thrive may result from decreased caloric intake due to oropharyngeal obstruction and an increased expenditure of energy associated with breathing. The consequences can be poor growth and development. Once the upper airway obstruction is relieved,the child often resumes a normal growth pattern.Severe and longstanding upper airway obstruction also may lead to serious cardiopulmonary abnormalities. Obstruction results in hypercarbia and hypoxemia, which adversely affect the cardiopulmonary system. Prolonged hypoxemia causes episodic pulmonary hypertension through vasoconstriction of the pulmonary circulation. Vasoconstriction occurs in an attempt to maximize ventilation and perfusion, but it leads to increased pulmonary vascular resistance. Hypercarbia worsens the pulmonary vasoconstriction. Prolonged exposure to this physiologic insult causes significant right ventricular strain that may lead to cor pulmonale and heart failure. Children who have bronchopulmonary disease, related to prematurity for example, are predisposed to deleterious effects from upper airway obstruction. Relief of the obstruction will assist in normalizing elevated pulmonary vascular resistance.Less severe in nature but more socially evident are the craniofacial growth effects of adenotonsillar hypertrophy. Nasopharyngeal obstruction results in obligate mouth breathing. Mouth breathing presumably causes changes in facial growth patterns as the tongue is placed in an abnormally low position to expand the oropharyngeal cavity. Over time, due to altered vectors of force on facial development, the child develops a long and narrow face, a narrow upper jaw, steep palate,and open bite deformities. This classically is referred to as “adenoid facies.”The vast majority of adenotonsillar complaints do not require diagnostic studies. Fiberoptic nasopharyngoscopy and laryngoscopy can be performed easily, provide useful information about potential causes of upper airway obstruction, and assist in treatment decision making. Lateral soft tissue radiographs may be useful in assessing the size of the adenoid pad and its relationship to the posterior nasal choanae. Plain radiographs also can demonstrate abscess formation or gas production in the cervical soft tissues. Occasionally,limited computed tomography may help to differentiate between a surgical emergency, such as deep neck space abscess, and a process that may be managed medically.Multichannel polysomnography is a useful modality for the evaluation of obstructive sleep apnea. The diagnostic criteria vary greatly among pediatric pulmonologists for diagnosing sleep apnea with the aid of polysomnography, but despite this variability, the study is proving useful in the preoperative evaluation of children in whom sleep architecture abnormalities are suspected.Laboratory studies are of limited usefulness unless a specific disease process is being investigated. For example, a monospot test for infectious mononucleosis has utility, and many physicians acquire a baseline complete blood count to compare with future studies for assessing medical progress. Preoperatively, a family history of bleeding abnormalities may indicate the need to perform a coagulation screen that includes a bleeding time, partial thromboplastin time, and prothrombin time.Most adenotonsillar infections are managed medically. Penicillin long has been the antibiotic of choice because most infections are caused by group A beta-hemolytic streptococci. Benzathine penicillin G administered intramuscularly has been the “gold standard,” but oral antibiotics are effective.Recurrent or chronic infections may be due to several causes. Errors of antibiotic dosage or duration or poor patient compliance result in frequent treatment failures. Selection of bacterial strains resistant to commonly used antibiotics is becoming more prevalent, and the presence of beta-lactamase-producing bacteria has forced a move to more powerful antibiotics. H influenzae and S aureus are two of the more common beta-lactamase producers. H influenzae has been cited as the most resistant bacterium and, therefore,is likely to be responsible for relapses. The use of cephalosporins,macrolides, and beta-lactamase inhibitors has improved medical treatment of chronic conditions. Prophylactic antibiotic therapy with sulfadimidine or penicillin once was used for recurrent or chronic cases,but this no longer is recommended because of the prevalence of resistant organisms.Attempts at treating symptomatic adenotonsillar hypertrophy with systemic corticosteroids have not yielded impressive results. Corticosteroids provide short-term improvement,but their use usually does not prevent a child from requiring a tonsillectomy and adenoidectomy if it otherwise is indicated.Surgical indications for tonsillectomy and adenoidectomy have been clearly established. They include patients who have three or more infections per year despite adequate medical therapy and hypertrophy causing upper airway obstruction,severe dysphagia, sleep disorders,cardiopulmonary complications, and dental malocclusion or affecting craniofacial growth. The presence of a peritonsillar abscess unresponsive to medical therapy and drainage documented by a surgeon and chronic or recurrent tonsillitis associated with a streptococcal carrier state not responding to beta-lactamase-resistant antibiotics are further indications. An adenoidectomy alone may be indicated for recurrent suppurative or otitis media with effusion.Tonsillectomy and adenoidectomy are among the most common surgical procedures performed in the United States, but they do entail risk. Reported mortality rates range from 1 in 16,000 to 35,000 operations. Deaths most commonly are related to anesthetic complications and hemorrhage. Morbidity in the postoperative period may result from postoperative hemorrhage, which usually is limited and rarely life-threatening unless the source of the bleeding originates with the carotid artery. Poor oral intake due to pain that results in dehydration, sore throat, referred otalgia, fever, and uvular swelling are more common postoperative complaints. Less common and more severe complications include atlantoaxial subluxation,mandible condyle fractures, eustachian tube injury, velopharyngeal incompetence, or nasapharyngeal stenosis.Velopharyngeal insufficiency(VPI) is a condition of abnormal airflow into the nasopharynx during speech caused by a congenital neuromuscular disorder or anatomic abnormality that prevents adequate and effective closure of the nasopharyngeal sphincter. It may occur after adenoidectomy, but usually lasts only for a few weeks to months. It is due primarily to removal of adenoids,but a tonsillectomy contributes by enlarging the nasapharyngeal airway size. Clinically significant VPI occurs in 1 in 1,500 to 3,000 patients, and they present with hypernasal speech (rhinolalia aperta)and nasal regurgitation. Patients at risk for postoperative VPI should be identified preoperatively. Overt or submucus soft palate cleft, bifid uvula, or V-shaped notched hard palate visible on physical examination are risk factors. Orofacial anomalies and children who have syndromes such as Treacher-Collins syndrome or Pierre-Robin sequence also are at increased risk. Those who have neuromuscular disorders such as Arnold-Chiari malformations,myotonic dystrophy, and Down syndrome require careful consideration and parental counseling before surgery. All of these situations place a child at increased risk for significant postoperative VPI and should be evaluated carefully. Those who have Down syndrome require special consideration not only because they are at risk for VPI, but because they are prone to atlantoaxial joint laxity, which places them at risk for subluxation during surgery due to head manipulation during a relaxed, anesthetic state. With careful preoperative preparation and thoughtful intraoperative care, these patients can undergo tonsillectomy and adenoidectomy procedures as safely and with as much benefit as other children.The frequency of tonsillitis and adenotonsillar hypertrophy requires a physician to have a thorough knowledge of these structures and of potential problems. Because adenotonsillar problems are seen so commonly,they have attained the status of a “routine” clinical visit or surgical procedure, which may result in a certain complacency among clinicians. It is important to be aware that there are many potential risks to inadequate evaluation and treatment that may result in potentially life-threatening situations. The vast majority of children are well cared for and receive beneficial medical or surgical treatment, but the potential for complications must be considered when evaluating any child who has an adenotonsillar complaint.