A parent brings her two year old son to your office because of a chief complaint of fussiness and tugging at his right ear for the past two days. He has had coughing and runny nose for about 5 days that has been treated with an over-the-counter cold medicine. He also has a low-grade fever of about 101 degrees axillary for the past two days. Both parents smoke cigarettes. He attends daycare. His past medical history is significant for ear infections in the past, with his last otitis media being 5 months ago treated with amoxicillin. His immunizations are up to date, including heptavalent pneumococcal vaccine.

Exam: VS T 38.4, P 100, RR 28, BP 100/65. He is active, alert to his surroundings and otherwise in no distress. HEENT: Right tympanic membrane is erythematous and bulging with poor mobility on pneumatic otoscopy. Left TM is clear with good mobility. Throat is non-erythematous. There are shotty cervical lymph nodes. Lungs are clear to auscultation. The rest of the examination is normal.

He is diagnosed with acute right otitis media. He is prescribed amoxicillin and acetaminophen. A follow-up visit is scheduled in 10 days.

Otitis media (OM) is one of the most common diagnoses that pediatricians encounter. It is estimated that otitis media comprises 23% of all office visits in the first year of life, and 40% at four to five years when these children start Kindergarten. In the United States, OM was the most frequent diagnosis in office settings, and accounted for 24.5 million visits in 1990 according to a report published by the Centers for Disease Control and Prevention (CDC) (1).

The middle ear is a gas filled cavity in the petrous part of the temporal bone between the external auditory canal and the inner ear. It contains three ossicles called the malleus, incus, and stapes. These ossicles conduct sound from the external auditory meatus to the inner ear. Therefore, factors hindering the movement of these ossicles, such as pus or fluid in the middle ear, will adversely affect hearing. The middle ear is connected to the nasopharynx by the eustachian tube. The eustachian tube allows for ventilation and clearance of fluid from the middle ear. Compared to the adult, the infant's eustachian tube is shorter, has a more acute angle, and has a smaller luminal area. Also, the angle of the tensor veli palatini muscle to the cartilage around the tube is variable, compared to being stable in the adult. The significance of these characteristics is that there is a greater likelihood that nasopharyngeal secretions can reflux or insufflate into the middle ear, and that clearance of the middle ear cavity of these secretions is decreased (2). These differences are the reason why there are more middle ear infections in the infant compared to the adult and older child.

Otitis media is common in infants and young children with the peak age being between 6 to 18 months of age. This is due not only to anatomical factors, but immunologic as well since these children still lack many protective antibodies against viral and bacterial organisms. The incidence of OM decreases after the first year of life and then increases again when the child enters school. It becomes less common after 7 years of age. Factors that increase the risk for OM are attendance in day care, second hand cigarette smoke exposure, craniofacial abnormalities such as cleft palate, and immunologic deficiencies. A protective factor is breastfeeding, which may be due to immune factors (e.g., secretory IgA and IgG), non-immune factors (e.g., interferon, glycoproteins, lactadherin), and anti-inflammatory factors (e.g., antioxidants, TNF-alpha, lactoferrin). Also, babies are breast-fed while in a vertical or semi-reclining position, compared to some babies who may be bottle fed while in a horizontal position. The practice of bottle feeding in the supine position is thought to increase OM by reflux of fluids from the nasopharynx into the middle ear (1).

The diagnosis of otitis media is a challenging one for pediatricians because of difficulty obtaining an adequate examination of the tympanic membrane (TM). The presence of cerumen and uncooperative and frightened patients complicate this. Common symptoms of OM are otalgia, otorrhea, and hearing loss. However, infants may only manifest otalgia by fussiness in the presence of fever. Other less common symptoms of OM and its complications are vertigo, nystagmus (unidirectional, horizontal, jerk type), tinnitus, swelling in the posterior auricular area (associated with mastoiditis), facial paralysis (due to disease within the temporal bone), and purulent conjunctivitis (which is associated with non-typable Haemophilus influenzae) (3). The best tool for the diagnosis of OM is the pneumatic otoscope. Inspection of the TM should include four characteristics: position, color, degree of translucency, and mobility. Also by visualizing the TM, one notices several landmarks such as the malleus which is divided into the short process, manubrium, and umbo; the long process of the incus; and the pars flaccida on the superior aspect and the pars tensa on the inferior aspect (3). It should be noted, although controversial, that a tympanic membrane may become red in a crying child (4). Other methods of diagnosing OM include tympanometry and tympanocentesis (3). This chapter will focus on two types of otitis media, namely acute otitis media and otitis media with effusion.

Acute otitis media (AOM) typically presents as a sudden onset of otalgia, fever, and hearing loss, which are preceded by an upper respiratory tract infection lasting for several days. Fever occurs in about 30-50% of patients of AOM, and is usually less than 40øC. Fever over 40øC suggests bacteremia or another complication (4). Pneumatic otoscopy reveals the TM that is opaque and bulging with poor mobility. Erythema, is a characteristic finding, but it may be absent. There may be perforation. Otitis media with effusion (OME), on the other hand, is asymptomatic in most children. Some may complain of hearing loss and less commonly tinnitus and vertigo. Older children may complain of a "plugged" feeling or "popping" in their ears, which is usually bilateral. The TM commonly appears opaque, but may be retracted or full. An air fluid level or bubbles may be seen. Mobility is also decreased. It is important to distinguish between the two diseases because the management of each is different, however, it is not easily done. Some key points would be that fever, irritability, definite redness and otalgia, and a bulging and opaque eardrum are associated with AOM, whereas absence of symptoms except for hearing loss, and a retracted eardrum are associated with OME. Both can present with middle ear effusion and decreased mobility of the TM (6,7).

If severe otalgia is present, then analgesia becomes a major therapeutic consideration. Minor pain can be treated with acetaminophen or ibuprofen in most instances. For more severe pain, topical anesthesia with benzocaine containing ear drops (e.g., Auralgan otic) can be administered in the office to see if satisfactory analgesia is achieved. If not, a stronger analgesic such as acetaminophen with codeine may be necessary. Although Auralgan otic is used for pain relief, one should be aware of allergic reactions and to make sure there is no perforation.

The management of otitis media is one of many controversial subjects in pediatrics. Most treat AOM with antibiotics as soon as it is diagnosed, whereas in OME, antibiotics may be deferred, unless it becomes chronic (3). The three most common organisms are Streptococcus pneumoniae, non-typable Haemophilus influenzae, and Moraxella catarrhalis. Other less common organisms are Streptococcus pyogenes, Staphylococcus aureus, gram negative enteric bacteria, and anaerobes (5). The choice of antibiotic is dependent on efficacy, palatability, side effects, convenience of dosing, and cost. The drug of choice against AOM remains amoxicillin, although bacterial resistance continues to be a problem. For this reason, it is recommended that the dose of amoxicillin be increased from 40-50 mg/kg/day to 80-90 mg/kg/day in two to three divided doses. However, children who are at low risk for resistant organisms may be treated with the lower dose of amoxicillin, being 40-50 mg/kg/day. Risk factors include young age (less than 2 years), recent antibiotic use (within the last month), and day care attendance (4). The consensus is less clear on second-line therapy if amoxicillin fails. The CDC suggests three drugs, amoxicillin-clavulanate (with the amoxicillin component of 80-90 mg/kg/day), cefuroxime axetil, and intramuscular ceftriaxone. In patients who are allergic to beta-lactam antibiotics, macrolides, like erythromycin plus sulfisoxazole, azithromycin, or clarithromycin, and trimethoprim-sulfamethoxazole may be used. The duration for treatment is 10 days, although azithromycin, cefpodoxime, and cefdinir are now approved for 5 days, and a single dose of intramuscular ceftriaxone is as effective as a 10-day course of amoxicillin. Also recently, azithromycin has been approved for a 30 mg/kg one time dose, or 10 mg/kg dose for three days. If the 30 mg/kg dose is used however, there is a 4.9% risk for emesis occurring, necessitating a repeat dose of medication. Other drugs that are recommended are cefprozil, ceftibuten, loracarbef, and clindamycin (6). The expected clinical course is improvement within 48-72 hours. Persistent otalgia, fever, and other systemic symptoms past 72 hours should be reevaluated. At times, tympanocentesis or myringotomy is necessary for resistant cases, at which time a culture can also be obtained. Follow-up visits are recommended 10-14 days later to determine the need for further antimicrobial treatment. Although a middle ear effusion may be present, an inflamed eardrum or persistent systemic symptoms at this follow-up visit may warrant changing the antibiotic therapy or performing a myringotomy/tympanocentesis. It is estimated that 30-70% of children will have a middle ear effusion 10-14 days later, and that without treatment, 6-26% will have a persistent middle ear effusion after 3 months, with the mean of resolution being about 23 days. Because middle ear effusions usually resolve spontaneously, the CDC and the American Academy of Pediatrics have recommended against re-treatment of infants and children who have persistent middle ear effusions and are asymptomatic. However, there is debate about what to do for children having OME for 2-3 months. An option is to treat non-surgically. Medications that have been studied are decongestants, antihistamines, oral corticosteroids, and antibiotics. The only drugs proved efficacious are oral corticosteroids and antibiotics; however, it is felt that the side effects from oral corticosteroids outweigh its benefits. Therefore, a ten-day course of amoxicillin remains as a reasonable treatment for chronic OME. Other antibiotics that have been recommended are cefaclor, erythromycin-sulfisoxazole, and ceftibuten, although these are either just as efficacious or less so than amoxicillin. Some of the decisions to treat chronic OME are significant conductive hearing loss; young infant since they cannot communicate their symptoms; associated suppurative upper respiratory tract infection; concurrent permanent conductive and sensorineural hearing loss; speech-language delay because of effusion and hearing loss; alterations in the tympanic membrane such as a retraction pocket; middle ear changes such as adhesive otitis media or involvement with the ossicles; previous surgery for otitis media; frequent recurrent episodes; and persistence of the effusion for 3 months or longer in both ears or 6 months or longer in one ear. If antibiotic therapy fails, then myringotomy with tympanostomy tube placement or myringotomy and adenoidectomy are recommended as the next step. Only ofloxacin otic solution is approved in children with acute otitis media with tympanostomy tubes or chronic suppurative otitis media with perforation (8).

Not only do we treat otitis media for symptomatic relief, but also to prevent its complications. The complications of OM include conductive and sensorineural hearing loss, mastoiditis, cholesteatoma, labyrinthitis, facial paralysis, meningitis, brain abscess, and lateral sinus thrombosis (9,10). Fortunately, because we live in the antibiotic era, these complications are rarely seen.

The prognosis for otitis media is excellent. In most children, otitis media resolves after antibiotic therapy. Only in a few children does medical therapy fail, and more aggressive measures are needed, such as myringotomy and tympanostomy tubes. Recently, a heptavalent pneumococcal conjugate vaccine (Prevnar) has been FDA approved and is a recommended childhood immunization by the AAP and CDC. This vaccine has been shown to reduce otitis media caused by pneumococcus; however, its greatest efficacy is in those patients with recurrent OM.

Otitis externa is another condition that is often seen in pediatrics. Four factors can lead to the development of otitis externa. They are excessive wetness (e.g., swimming), dryness (e.g., lack of cerumen and dry ear skin), other skin diseases (e.g., dermatitis, previous infection), and trauma (e.g., using cotton tipped applicators). It is also called swimmer's ear, although it can occur without swimming (4). The pathophysiology of otitis externa is the following. As the humidity in the outer ear increases, the stratum corneum in the cartilaginous portion of the ear absorbs water, which results in edema. Edema blocks the pilosebaceous units in the ear, thereby decreasing the excretion of cerumen. A decrease in cerumen causes an increase in the pH of the external ear, in addition to decreasing its water repelling covering. The exposed skin becomes susceptible to maceration and the higher pH becomes a favorable environment for bacteria such as Pseudomonas. Bacteria can then penetrate through the dermis after superficial breakdown or through minor trauma such as with cotton applicators. Inflammation and infection thus results. The most common organisms cultured in otitis externa are Pseudomonas and Staphylococcus aureus. Other organisms that can be cultured are Enterobacter aerogenes, Proteus mirabilis, Klebsiella pneumoniae, streptococci, coagulase-negative staphylococci, diphtheroids, and fungi such as Aspergillus and Candida. Symptoms initially include pruritus and aural fullness, which then progresses to ear pain that may be severe and out of proportion to its appearance. Purulent otorrhea and hearing loss from edema of the canal may be present as well. Examination shows an inflamed and erythematous cartilaginous canal, with variable involvement of the bony canal. Manipulation of the pinna and pressure on the tragus elicits pain. Although the tympanic membrane is not affected, it and the medial portion of the canal can become involved and often look granular. When this happens, pneumatic otoscopy is needed to rule out concomitant otitis media. Tender and palpable lymph nodes may be present in the periauricular and preauricular areas. Treatment includes the use of ototopical drops, such as a combination of polymyxin B, neomycin, and hydrocortisone (Cortisporin otic). Polymyxin B is active against gram negative bacilli such as Pseudomonas, neomycin is active against gram positive organisms and some gram negatives especially Proteus, and the corticosteroid reduces inflammation and edema. Fluoroquinolones are a new class of antibiotics for otitis externa; ofloxacin and ciprofloxacin are both currently available. If there is a lot of fluid drainage, it may be preferable to wick out most of the fluid prior to instilling the drops. If there is severe edema preventing effective instillation of drops, a wick can be placed in the membranous canal with otic drops applied several times a day, the wick can be replaced every 48 to 72 hours until the edema resolves (11). After 2-3 days, the edema of the ear canal is usually markedly improved. Analgesics such as ibuprofen and codeine can be used to treat severe pain. Cleaning the ear canal such as irrigating with 2% acetic acid to remove debris can be a useful adjunct to therapy. Prevention may be necessary for those patients who suffer from recurrences. Dilute alcohol or acetic acid (2%) can be instilled immediately after swimming or bathing, and is the best prophylaxis. Patients should protect their ears from water when bathing and should avoid swimming until their otitis externa resolves (4).

Questions

1. When is the peak age of otitis media?

2. What are some risk factors for otitis media?

3. What is the BEST tool for diagnosing otitis media (not gold standard)?

4. What is the difference between acute otitis media and otitis media with effusion?

5. What are the three most common organisms that cause otitis media?

6. What antibiotic is the drug of choice against otitis media?

7. What are the three second-line antibiotics recommended by the CDC if amoxicillin fails?

8. What are some reasons to treat chronic otitis media with effusion with either antibiotics or tympanostomy tubes?

9. What are some complications of otitis media?

10. What is the most common organism cultured in otitis externa?

11. What are four factors that can predispose a patient to develop otitis externa?

12. What can be instilled in the ear to prevent otitis externa in an otitis externa prone child?

References

1. Bluestone CD, Klein JO. Chapter 4 - Epidemiology. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 58-78.

2. Bluestone CD, Klein JO. Chapter 2 - Anatomy. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 16-33.

3. Bluestone CD, Klein JO. Chapter 7-Diagnosis. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 120-179.

4. Kenna M. Part 29-The Ear. In: Behrman RE, et al (eds). Nelson Textbook of Pediatrics, 16th edition. 2000, Philadelphia: W.B. Saunders Company, pp. 1938-1964.

5. Berman S. Otitis Media in Children. New Engl J Med 1995;332(23):1560-1565.

6. Rosenfeld RM. An Evidence-Based Approach to Treating Otitis Media. Pediatr Otolaryngol 1996;43(6):1165-1181.

7. Bluestone CD, Klein JO. Chapter 1-Definitions, Terminology, and Classification. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 1-15.

8. Bluestone CD, Klein JO. Chapter 8-Management. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 180-298.

9. Bluestone CD, Klein JO. Chapter 9-Complications and Sequelae: Infratemporal. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 299-381.

10. Bluestone CD, Klein JO. Chapter 10-Complications and Sequelae: Intracranial. In: Bluestone CD, Klein JO. Otitis Media in Infants and Children, 3rd edition. 2001, Philadelphia: W.B. Saunders Company, pp. 382-396.

11. Kryzer TC, Lambert PR. Chapter 20-Diseases of the External Auditory Canal. In: Canalis RF, Lambert PR. The Ear. 2000, Philadelphia: Lippincott Williams & Wilkins, pp. 341-357.

Answers to questions

1. 6 to 18 months of age.

2. Attendance in day-care, second-hand cigarette smoke exposure, craniofacial abnormalities, bottle-feeding in the horizontal position.

3. Pneumatic otoscopy (myringotomy/tympanocentesis is the gold standard, but not the best diagnostic tool because of its invasiveness).

4. AOM: otalgia, fever, hearing loss, associated with upper respiratory tract infection; TM that is opaque or erythematous and bulging with poor mobility, perforation. OME: commonly asymptomatic but may have hearing loss; retracted TM.

5. Streptococcus pneumoniae, non-typable Haemophilus influenzae, Moraxella catarrhalis.

6. Amoxicillin

7. Amoxicillin-clavulanic acid, cefuroxime axetil, intramuscular ceftriaxone

8. Significant conductive hearing loss; young infant since they cannot communicate their symptoms; associated suppurative upper respiratory tract infection; concurrent permanent conductive and sensorineural hearing loss; speech-language delay because of effusion and hearing loss; alterations in the tympanic membrane such as a retraction pocket; middle ear changes such as adhesive otitis media or involvement with the ossicles; previous surgery for otitis media; frequent recurrent episodes; and persistence of the effusion for 3 months or longer in both ears or 6 months or longer in one ear.

9. Conductive and sensorineural hearing loss, mastoiditis, cholesteatoma, labyrinthitis, facial paralysis, meningitis, brain abscess, and lateral sinus thrombosis.

10. Pseudomonas aeruginosa.

11. Excessive wetness, lack of cerumen, preexisting skin problems, and trauma.

12. 2% acetic acid or dilute alcohol.

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