Adenoid hypertrophy is an obstructive condition related to an increased size of the adenoids. The condition can occur with or without an acute or chronic infection of the adenoids. The adenoids, also known as the pharyngeal tonsils, are a collection of lymphoepithelial tissue in the superior aspect of the nasopharynx medial to the Eustachian tube orifices. In conjunction with the palatine tonsils, lingual tonsils, and tubal tonsils, the adenoids make up the structure known as Waldeyer's Ring, a collection of mucosal-associated lymphoid tissue situated at the entrance of the upper aerodigestive tract. Blood supply to the adenoids includes the ascending pharyngeal artery, with some contributions from the internal maxillary and facial arteries. The glossopharyngeal and vagus nerves provide sensory innervation to the adenoids. Adenoid size tends to increase during childhood, usually reaching maximal size by age 6 or 7 before regressing by adolescence.
Adenoid hypertrophy can occur because of infectious and non-infectious etiologies. Infectious causes of adenoid hypertrophy include both viral and bacterial pathogens. Viral pathogens associated with adenoid hypertrophy include adenovirus, coronavirus, coxsackievirus, cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus, human bocavirus parainfluenza virus, and rhinovirus. Many aerobic bacterial species have been implicated in contributing to infectious adenoid hypertrophy including alpha-, beta-, and gamma-hemolytic Streptococcus species, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, Neisseria gonorrhoeae, Corynebacterium diphtheriae, Chlamydophila pneumoniae, and Mycoplasma pneumoniae. Fusobacterium, Peptostreptococcus, and Prevotella species have also been identified as anaerobic organisms involved in causing infectious adenoid hypertrophy. Multiple non-infectious causes of adenoid hypertrophy have also been suggested including gastroesophageal reflux, allergies, and exposure to cigarette smoke. In adults, adenoid hypertrophy can also be a sign of a more serious condition such as HIV infection, lymphoma, or sino-nasal malignancy.
Adenoid hypertrophy is an obstructive condition, with its symptomatology depending on the obstructed structure. Nasal obstruction by hypertrophic adenoid tissue can cause the patient to complain of rhinorrhea, difficulty breathing through the nose, chronic cough, post-nasal drip, snoring, and/or sleep disordered breathing in children. If nasal obstruction is significant, the patient can suffer from sinusitis as a result and may complain of facial pain or pressure. Obstruction of the Eustachian tube can lead to symptoms consistent with Eustachian tube dysfunction such as muffled hearing, otalgia, crackling or popping sounds in the ear, and/or recurrent middle ear infections.
On physical exam, the patient with adenoid hypertrophy will often breathe through the mouth, have a hypo nasal character to their voice, and may have the facial characteristics known as adenoid facies which include a high arched hard palate, increased facial height, and retrognathia. A complete physical exam should aim to rule out other potential causes of nasal obstruction such as nasal foreign bodies, rhinosinusitis, nasal polyposis, and congenital abnormalities such as choanal atresia or pyriform aperture stenosis.
A thorough history and physical exam are often sufficient to diagnosed adenoid hypertrophy. Lateral head and neck radiography have been used for assessment of the adenoids, especially in fussy or non-cooperative children. Videofluoroscopy has also been described as a method for determining the degree of adenoid hypertrophy. Both of these radiographic methods have shown some reliability in diagnosing adenoid hypertrophy. However, both also come with the risk of potentially unnecessary exposure to radiation. Direct visualization of the adenoids by fiberoptic nasopharyngoscopy is another option for assessing the adenoids in the clinical setting with good reliability and without unnecessary exposure to radiation.
In acute and chronic infectious adenoid hypertrophy, medical management with antibiotics is an appropriate first step. Amoxicillin can be used for uncomplicated acute adenoiditis, however, a beta-lactamase inhibitor such as clavulanic acid should be included for chronic or recurrent infections. Clindamycin or azithromycin are considered as alternatives in patients with penicillin allergies. Nasal steroids have been suggested as an additional option for medical treatment with some short-term success noted, overall the evidence is mixed as to the efficacy of these medications.
Adenoidectomy is the surgical treatment option of choice for adenoid hypertrophy. Adenoidectomy is considered for patients with recurrent or persistent obstructive or infectious symptoms related to adenoid hypertrophy. Adenoidectomy is performed under general anesthesia with the patient in the supine position with the neck extended slightly and the surgeon seated at the head of the operating table. Adequate exposure of the posterior pharynx is achieved by use of a self-retaining oral retractor, such as a Crowe-Davis mouth gag, and the adenoids are visualized using an angled mirror. Many techniques have been described for performing an adenoidectomy. Sharp instruments such as the adenoid curette or adenotome can be used to sharply dissect the adenoid tissue from the posterior pharyngeal wall, followed by packing of the pharynx or use of suction electrocautery for hemostasis. Suction electrocautery, co-ablation, plasma, laser, and microdebrider instruments have all been described in the literature as tools used for the removal of excessive adenoid tissue during adenoidectomy. Regardless of the tools employed, the goal of adenoidectomy is the surgical reduction of adenoid tissue mass and/or to eliminate bacterial biofilm from the surface of the adenoid tissue.
Symptoms of adenoid hypertrophy are primarily related to nasal obstruction and Eustachian tube dysfunction. Thus the differential diagnosis should include other causes for these non-specific symptoms, such as:
Adenoid hypertrophy is generally a self-limiting condition which resolves as the adenoids atrophy and regress by adolescence. However, given the potentially serious complications and impact on patient quality of life, surgical management of adenoid hypertrophy is employed for many patients annually. Illustrating this fact, in 2006 there were approximately 506,778 adenotonsillectomies and 129,540 adenoidectomies performed in the United States.
Complications of adenoid hypertrophy are often seen as complications of persistent middle ear effusion and/or sleep disordered breathing which can occur as a result of untreated adenoid hypertrophy. Children with adenoid hypertrophy are at risk for developing speech, language, and/or learning difficulties as a result of conductive hearing loss which can occur with persistent middle ear effusion. Adenoid hypertrophy also places patients at risk for sleep-disordered breathing and sleep apnea which in children can lead to behavioral problems, bedwetting, pulmonary hypertension and psychiatric disorders such as depression and ADHD.
Referral for evaluation by an otolaryngologist should be considered in any child with symptoms suggestive of sleep-disordered breathing, persistent middle ear effusion, and/or recurrent throat infections despite adequate treatment with antibiotics.
Educating patients, physicians, and allied health professionals is a key component of providing the best evidence-based care possible to achieve improved patient outcomes.
Multidisciplinary team-based clinics have shown promise in improving health outcomes. Pediatric multidisciplinary aerodigestive clinics are a common example of this model of patient care. In a recent longitudinal case series of patients with persistent symptoms after evaluation and treatment by a single specialist, 73% of patients showed significant improvement in their presenting symptoms after treatment at a multidisciplinary aerodigestive clinic. (Level V)
While each medical professional certainly has his or her role to play in providing excellent patient care, it is important to consider the collective benefit of a more collaborative team-based approach to providing comprehensive medical care.