What is Acute otitis media? What are causes,risk Factors, symptoms, diagnosis, treatment and prevention

 

Acute otitis media

Acute otitis media is a bacterial or viral infection of the middle ear, usually accompanying an upper respiratory infection. Symptoms include otalgia (ear pain), often with systemic symptoms (eg, fever, nausea, vomiting, diarrhea), especially in the very young children. Diagnosis is based on otoscopy. Treatment is with analgesics and sometimes antibiotics.

Although acute otitis media can occur at any age, it is most common between ages 3 months and 3 years. At this age, the eustachian tube is structurally and functionally immature—the angle of the eustachian tube is more horizontal, and the angle of the tensor veli palatini muscle and the cartilaginous eustachian tube renders the opening mechanism less efficient. Anything that causes the eustachian tubes to become swollen or blocked makes more fluid build up in the middle ear behind the eardrum.

The cause of acute otitis media may be viral or bacterial. Viral infections are often complicated by secondary bacterial infection. In neonates, Gram-negative enteric bacilli, particularly Escherichia coli, and Staphylococcus aureus cause acute otitis media. In older infants and children < 14 years, the most common organisms are Streptococcus pneumoniae, Moraxella (Branhamella) catarrhalis, and nontypeable Haemophilus influenzae; less common causes are group A β-hemolytic streptococci and Staphylococcus aureus. In patients > 14 years, Streptococcus pneumoniae, group A β-hemolytic streptococci, and Staphylococcus aureus are most common, followed by Haemophilus influenzae.

Acute otitis media:

Acute otitis media causes

Acute otitis media usually starts with a cold or a sore throat caused by bacteria or a virus. The infection spreads through the back of the throat to the middle ear, to which it is connected by the eustachian tube (also called auditory tube). The infection in the middle ear causes swelling and fluid build-up, which puts pressure on the eardrum.

Acute otitis media are common in infants and children because the eustachian tubes are easily clogged. Acute otitis media can also occur in adults, although they are less common than in children.

The eustachian tube runs from the middle of each ear to the back of the throat (see Figures 1 and 2). Normally, the eustachian tube drains fluid that is made in the middle ear. If the eustachian tube gets blocked, fluid can build up. This can lead to infection.

Anything that causes the eustachian tubes to become swollen or blocked makes more fluid build up in the middle ear behind the eardrum. Some causes are:

• Allergies
• Colds and sinus infections
• Excess mucus and saliva produced during teething
• Infected or overgrown adenoids (lymph tissue in the upper part of the throat)
• Tobacco smoke

Acute otitis media are also more likely in children who spend a lot of time drinking from a sippy cup or bottle while lying on their back. Getting water in the ears will not cause an acute ear infection, unless the eardrum has a hole in it.

Usually, acute otitis media is a complication of eustachian tube dysfunction that occurred during an acute viral upper respiratory tract infection. Bacteria can be isolated from middle ear fluid cultures in 50% to 90% of cases of acute otitis media and serous otitis media 1). Streptococcus pneumoniae, Haemophilus influenzae (nontypable), and Moraxella catarrhalis are the most common organisms 2). Haemophilus influenzae has become the most prevalent organism among children with severe or refractory acute otitis media following the introduction of the pneumococcal conjugate vaccine.

Acute otitis media most often occur in the winter. You cannot catch an ear infection from someone else. But a cold that spreads among children may cause some of them to get ear infections.

Adults

There is little published information to guide the management of otitis media in adults. Adults with new-onset unilateral, recurrent acute otitis media (greater than two episodes per year) or persistent otitis media with effusion (greater than six weeks) should receive additional evaluation to rule out a serious underlying condition, such as mechanical obstruction, which in rare cases is caused by nasopharyngeal carcinoma. Isolated acute otitis media or transient otitis media with effusion may be caused by eustachian tube dysfunction from a viral upper respiratory tract infection; however, adults with recurrent acute otitis media or persistent otitis media with effusion should be referred to an otolaryngologist.

Risk factors for acute otitis media

The presence of smoking in the household is a significant risk factor for acute otitis media. Other risk factors include a strong family history of otitis media, bottle feeding (ie, instead of breastfeeding), and attending a day care center.

Risk factors for acute otitis media 4):

• Age (younger)
• Allergies
• Craniofacial abnormalities
• Exposure to environmental smoke or other respiratory irritants
• Attending day care (especially centers with more than 6 children)
• Family history of recurrent acute otitis media
• Gastroesophageal reflux
• Immunodeficiency
• No breastfeeding
• Pacifier use
• Upper respiratory tract infections (URTI)
• Changes in altitude or climate
• Cold climate
• Not being breastfed
• Recent ear infection
• Recent illness of any type (because illness lowers the body’s resistance to infection)

Acute otitis media prevention

Routine childhood vaccination against pneumococci (with pneumococcal conjugate vaccine), Haemophilus influenzae type B, and influenza decreases the incidence of acute otitis media. Infants should not sleep with a bottle, and elimination of household smoking may decrease incidence. Prophylactic antibiotics are not recommended for children who have recurrent episodes of acute otitis media.

Recurrent acute otitis media and recurrent secretory otitis media may be prevented by the insertion of tympanostomy tubes.

Acute otitis media

Acute otitis media is a bacterial or viral infection of the middle ear, usually accompanying an upper respiratory infection. Symptoms include otalgia (ear pain), often with systemic symptoms (eg, fever, nausea, vomiting, diarrhea), especially in the very young children. Diagnosis is based on otoscopy. Treatment is with analgesics and sometimes antibiotics.

Although acute otitis media can occur at any age, it is most common between ages 3 months and 3 years. At this age, the eustachian tube is structurally and functionally immature—the angle of the eustachian tube is more horizontal, and the angle of the tensor veli palatini muscle and the cartilaginous eustachian tube renders the opening mechanism less efficient. Anything that causes the eustachian tubes to become swollen or blocked makes more fluid build up in the middle ear behind the eardrum.

The cause of acute otitis media may be viral or bacterial. Viral infections are often complicated by secondary bacterial infection. In neonates, Gram-negative enteric bacilli, particularly Escherichia coli, and Staphylococcus aureus cause acute otitis media. In older infants and children < 14 years, the most common organisms are Streptococcus pneumoniae, Moraxella (Branhamella) catarrhalis, and nontypeable Haemophilus influenzae; less common causes are group A β-hemolytic streptococci and Staphylococcus aureus. In patients > 14 years, Streptococcus pneumoniae, group A β-hemolytic streptococci, and Staphylococcus aureus are most common, followed by Haemophilus influenzae.

Figure 1. Ear anatomy

Figure 2. Middle ear and auditory ossicles

Figure 3. Acute otitis media

Footnote: Otoscopic view of acute otitis media. Erythema and bulging of the tympanic membrane with loss of normal landmarks are noted.

Acute otitis media causes

Acute otitis media usually starts with a cold or a sore throat caused by bacteria or a virus. The infection spreads through the back of the throat to the middle ear, to which it is connected by the eustachian tube (also called auditory tube). The infection in the middle ear causes swelling and fluid build-up, which puts pressure on the eardrum.

Acute otitis media are common in infants and children because the eustachian tubes are easily clogged. Acute otitis media can also occur in adults, although they are less common than in children.

The eustachian tube runs from the middle of each ear to the back of the throat (see Figures 1 and 2). Normally, the eustachian tube drains fluid that is made in the middle ear. If the eustachian tube gets blocked, fluid can build up. This can lead to infection.

Anything that causes the eustachian tubes to become swollen or blocked makes more fluid build up in the middle ear behind the eardrum. Some causes are:

• Allergies
• Colds and sinus infections
• Excess mucus and saliva produced during teething
• Infected or overgrown adenoids (lymph tissue in the upper part of the throat)
• Tobacco smoke

Acute otitis media are also more likely in children who spend a lot of time drinking from a sippy cup or bottle while lying on their back. Getting water in the ears will not cause an acute ear infection, unless the eardrum has a hole in it.

Usually, acute otitis media is a complication of eustachian tube dysfunction that occurred during an acute viral upper respiratory tract infection. Bacteria can be isolated from middle ear fluid cultures in 50% to 90% of cases of acute otitis media and serous otitis media 1). Streptococcus pneumoniae, Haemophilus influenzae (nontypable), and Moraxella catarrhalis are the most common organisms 2). Haemophilus influenzae has become the most prevalent organism among children with severe or refractory acute otitis media following the introduction of the pneumococcal conjugate vaccine 3).

Acute otitis media most often occur in the winter. You cannot catch an ear infection from someone else. But a cold that spreads among children may cause some of them to get ear infections.

Adults

There is little published information to guide the management of otitis media in adults. Adults with new-onset unilateral, recurrent acute otitis media (greater than two episodes per year) or persistent otitis media with effusion (greater than six weeks) should receive additional evaluation to rule out a serious underlying condition, such as mechanical obstruction, which in rare cases is caused by nasopharyngeal carcinoma. Isolated acute otitis media or transient otitis media with effusion may be caused by eustachian tube dysfunction from a viral upper respiratory tract infection; however, adults with recurrent acute otitis media or persistent otitis media with effusion should be referred to an otolaryngologist.

Risk factors for acute otitis media

The presence of smoking in the household is a significant risk factor for acute otitis media. Other risk factors include a strong family history of otitis media, bottle feeding (ie, instead of breastfeeding), and attending a day care center.

Risk factors for acute otitis media 4):

• Age (younger)
• Allergies
• Craniofacial abnormalities
• Exposure to environmental smoke or other respiratory irritants
• Attending day care (especially centers with more than 6 children)
• Family history of recurrent acute otitis media
• Gastroesophageal reflux
• Immunodeficiency
• No breastfeeding
• Pacifier use
• Upper respiratory tract infections (URTI)
• Changes in altitude or climate
• Cold climate
• Not being breastfed
• Recent ear infection
• Recent illness of any type (because illness lowers the body’s resistance to infection)

Acute otitis media prevention

Routine childhood vaccination against pneumococci (with pneumococcal conjugate vaccine), Haemophilus influenzae type B, and influenza decreases the incidence of acute otitis media. Infants should not sleep with a bottle, and elimination of household smoking may decrease incidence. Prophylactic antibiotics are not recommended for children who have recurrent episodes of acute otitis media.

Recurrent acute otitis media and recurrent secretory otitis media may be prevented by the insertion of tympanostomy tubes.

• Wash hands and toys often.
• If possible, choose a day care that has 6 or fewer children. This can reduce your child’s chances of getting a cold or other infection, and lead to fewer ear infections.
• DO NOT use pacifiers.
• Breastfeed — This makes a child much less prone to ear infections. If you are bottle feeding, hold your infant in an upright, seated position.
• DO NOT expose your child to secondhand smoke.
• Make sure your child’s immunizations are up to date. The pneumococcal vaccine prevents infections from the bacteria that most commonly cause acute ear infections and many respiratory infections.
• DO NOT overuse antibiotics. Doing so can lead to antibiotic resistance.

Acute otitis media symptoms

The usual initial symptom is earache, often with hearing loss.

In infants, often the main sign of an acute otitis media is acting irritable, cranky or crying that cannot be soothed. Many infants and children with an acute ear infection have a fever or trouble sleeping. Fever, nausea, vomiting, and diarrhea often occur in young children. Tugging on the ear is not always a sign that the child has an ear infection.

Symptoms of an acute otitis media in older children or adults include:

• Ear pain or earache
• Fullness in the ear
• Feeling of general illness
• Vomiting
• Diarrhea
• Hearing loss in the affected ear

Sudden drainage of yellow or green fluid from the ear may mean the eardrum has ruptured.

All acute ear infections involve fluid behind the eardrum. At home, you can use an electronic ear monitor to check for this fluid. You can buy this device at a drugstore. You still need to see a health care provider to confirm an ear infection.

Otoscopic examination can show a bulging, erythematous tympanic membrane (eardrum) with indistinct landmarks and displacement of the light reflex. Air insufflation (pneumatic otoscopy) shows poor mobility of the eardrum. Spontaneous perforation of the eardrum (tympanic membrane) causes serosanguineous or purulent ear discharge (otorrhea).

Severe headache, confusion, or focal neurologic signs may occur with intracranial spread of infection. Facial paralysis or vertigo suggests local extension to the fallopian canal or labyrinth.

Acute otitis media complications

Complications of acute otitis media are uncommon. In rare cases, bacterial middle ear infection spreads locally, resulting in acute mastoiditis (an infection of the bones around the skull), petrositis, or labyrinthitis. Intracranial spread is extremely rare and usually causes meningitis, but brain abscess, subdural empyema, epidural abscess, lateral sinus thrombosis, or otitic hydrocephalus may occur. Even with antibiotic treatment, intracranial complications are slow to resolve, especially in immunocompromised patients.

Acute otitis media diagnosis

Diagnosis of acute otitis media usually is clinical, based on the presence of acute (within 48 hours) onset of pain, bulging of the tympanic membrane and, particularly in children, the presence of signs of middle ear effusion on pneumatic otoscopy. Except for fluid obtained during myringotomy, cultures are not generally done.

Previous diagnostic criteria for acute otitis media were based on symptomatology without otoscopic findings of inflammation. The updated American Academy of Pediatrics guideline endorses more stringent otoscopic criteria for diagnosis 5). An acute otitis media diagnosis requires moderate to severe bulging of the tympanic membrane (see Figure 3), new onset of ear discharge (otorrhea) not caused by otitis externa, or mild bulging of the tympanic membrane associated with recent onset of ear pain (less than 48 hours) or erythema. acute otitis media should not be diagnosed in children who do not have objective evidence of middle ear effusion  6). An inaccurate diagnosis can lead to unnecessary treatment with antibiotics and contribute to the development of antibiotic resistance.

Otitis media with effusion (serous otitis media) is defined as middle ear effusion in the absence of acute symptoms 7). If otitis media with effusion is suspected and the presence of effusion on otoscopy is not evident by loss of landmarks, pneumatic otoscopy, tympanometry, or both should be used 8). Pneumatic otoscopy is a useful technique for the diagnosis of acute otitis media and otitis media with effusion 9) and is 70% to 90% sensitive and specific for determining the presence of middle ear effusion. By comparison, simple otoscopy is 60% to 70% accurate 10). Inflammation with bulging of the tympanic membrane on otoscopy is highly predictive of acute otitis media 11). Pneumatic otoscopy is most helpful when ear wax (cerumen) is removed from the external auditory canal.

Tympanometry and acoustic reflectometry are valuable adjuncts to otoscopy or pneumatic otoscopy 12). Tympanometry has a sensitivity and specificity of 70% to 90% for the detection of middle ear fluid, but is dependent on patient cooperation 13). Combined with normal otoscopy findings, a normal tympanometry result may be helpful to predict absence of middle ear effusion. Acoustic reflectometry has lower sensitivity and specificity in detecting middle ear effusion and must be correlated with the clinical examination 14). Tympanocentesis is the preferred method for detecting the presence of middle ear effusion and documenting bacterial cause 15), but is rarely performed in the primary care setting.

Acute otitis media treatment

Painkillers or pain relievers should be provided when necessary, including to pre-verbal children with behavioral manifestations of pain (eg, tugging or rubbing the ear, excessive crying or fussiness). Painkillers are recommended for symptoms of ear pain, fever, and irritability 16). Painkillers are particularly important at bedtime because disrupted sleep is one of the most common symptoms motivating parents to seek care 17). Oral analgesics, such as acetaminophen or ibuprofen have been shown to be effective; weight-based doses are used for children 18). Ibuprofen is preferred, given its longer duration of action and its lower toxicity in the event of overdose 19). Topical analgesics, such as benzocaine, can also be helpful 20). A variety of topical agents are available by prescription and over the counter. Although not well studied, some topical agents may provide transient relief but probably not for more than 20 to 30 minutes. Topical agents should not be used when there is a tympanic membrane perforation.

Although 80% of cases resolve spontaneously, in the US, antibiotics are often given. Antibiotics relieve symptoms quicker (although results after 1 to 2 weeks are similar) and may reduce the chance of residual hearing loss and labyrinthine or intracranial complications. However, with the recent emergence of resistant organisms, pediatric organizations have strongly recommended initial antibiotics only for certain children (eg, those who are younger or more severely ill or for those with recurrent acute otitis media (eg, ≥ 4 episodes in 6 months). Antibiotics should be routinely prescribed for children with acute otitis media who are six months or older with severe signs or symptoms (i.e., moderate or severe otalgia, otalgia for at least 48 hours, or temperature of 102.2°F [39°C] or higher), and for children younger than two years with bilateral acute otitis media regardless of additional signs or symptoms 21).

Others, provided there is good follow-up, can safely be observed for 48 to 72 hours and given antibiotics only if no improvement is seen; if follow-up by phone is planned, a prescription can be given at the initial visit to save time and expense. Decision to observe should be discussed with the caregiver.

Among children with mild symptoms, observation may be an option in those six to 23 months of age with unilateral acute otitis media, or in those two years or older with bilateral or unilateral acute otitis media 22). A large prospective study of this strategy found that two out of three children will recover without antibiotics 23). Recently, the American Academy of Family Physicians recommended not prescribing antibiotics for otitis media in children two to 12 years of age with nonsevere symptoms if observation is a reasonable option 24). If observation is chosen, a mechanism must be in place to ensure appropriate treatment if symptoms persist for more than 48 to 72 hours. Strategies include a scheduled follow-up visit or providing patients with a backup antibiotic prescription to be filled only if symptoms persist 25).

In adults, topical intranasal vasoconstrictors, such as phenylephrine 0.25% 3 drops every 3 hours, improve eustachian tube function. To avoid rebound congestion, these preparations should not be used > 4 days. Systemic decongestants (eg, pseudoephedrine 30 to 60 mg orally every 6 hours as needed) may be helpful. Antihistamines (eg, chlorpheniramine 4 mg orally every 4 to 6 hours for 7 to 10 days) may improve eustachian tube function in people with allergies but should be reserved for the truly allergic.

For children, neither vasoconstrictors nor antihistamines are of benefit.

Myringotomy may be done for a bulging tympanic membrane, particularly if severe or persistent pain, fever, vomiting, or diarrhea is present. The patient’s hearing, tympanometry, and tympanic membrane appearance and movement are monitored until normal.

Acute otitis media antibiotics

A virus or bacteria can cause acute otitis media. Antibiotics will not help an infection that is caused by a virus. Most health care providers don’t prescribe antibiotics for every ear infection. However, all children younger than 6 months with acute otitis media are treated with antibiotics.

Your child’s doctor is more likely to prescribe antibiotics if your child:

• Is under age 2
• Has a fever
• Appears sick
• Does not improve in 24 to 48 hours

If antibiotics are prescribed, it is important to take them every day and to take all of the medicine. DO NOT stop the medicine when symptoms go away. If the antibiotics do not seem to be working within 48 to 72 hours, contact your provider. You may need to switch to a different antibiotic.

Side effects of antibiotics may include nausea, vomiting, and diarrhea. Although rare, serious allergic reactions may also occur.

Some children have repeat ear infections that seem to go away between episodes. They may receive a smaller, daily dose of antibiotics to prevent new infections.

Tables 1 and 2 summarize the antibiotic options for children with acute otitis media. High-dose amoxicillin should be the initial treatment in the absence of a known allergy 26) The advantages of amoxicillin include low cost, acceptable taste, safety, effectiveness, and a narrow microbiologic spectrum. Children who have taken amoxicillin in the past 30 days, who have conjunctivitis, or who need coverage for β-lactamase–positive organisms should be treated with high-dose amoxicillin/clavulanate (Augmentin) 27).

Oral cephalosporins, such as cefuroxime (Ceftin), may be used in children who are allergic to penicillin. Recent research indicates that the degree of cross reactivity between penicillin and second- and third-generation cephalosporins is low (less than 10% to 15%), and avoidance is no longer recommended 28). Because of their broad-spectrum coverage, third-generation cephalosporins in particular may have an increased risk of selection of resistant bacteria in the community 29). High-dose azithromycin (Zithromax; 30 mg per kg, single dose) appears to be more effective than the commonly used five-day course, and has a similar cure rate as high-dose amoxicillin/clavulanate 30). However, excessive use of azithromycin is associated with increased resistance, and routine use is not recommended 31). Trimethoprim/sulfamethoxazole is no longer effective for the treatment of acute otitis media due to evidence of Streptococcus pneumoniae resistance 32).

Intramuscular or intravenous ceftriaxone (Rocephin) should be reserved for episodes of treatment failure or when a serious comorbid bacterial infection is suspected 33). One dose of ceftriaxone may be used in children who cannot tolerate oral antibiotics because it has been shown to have similar effectiveness as high-dose amoxicillin 34). A three-day course of ceftriaxone is superior to a one-day course in the treatment of nonresponsive acute otitis media caused by penicillin-resistant Streptococcus pneumoniae 35). Although some children will likely benefit from intramuscular ceftriaxone, overuse of this agent may significantly increase high-level penicillin resistance in the community 36). High-level penicillin-resistant pneumococci are also resistant to first- and third-generation cephalosporins.

Antibiotic therapy for acute otitis media is often associated with diarrhea 37). Probiotics and yogurts containing active cultures reduce the incidence of diarrhea and should be suggested for children receiving antibiotics for acute otitis media 38). There is no compelling evidence to support the use of complementary and alternative treatments in acute otitis media 39).

Table 1. Antibiotics for Otitis Media

Drug	Dose* (by Age)	Comments
Initial treatment
Amoxicillin	< 14 years: 40–45 mg/kg every 12 hours > 14 years: 500 mg every 8 hours	Preferred unless the child has one of the following: Received amoxicillin in the past 30 days Purulent conjunctivitis Recurrent acute otitis media unresponsive to amoxicillin High-dose regimen for possible resistant organisms
Penicillin-allergic†
Cefdinir	14 mg/kg once a day or 7 mg/kg every 12 hours	—
Cefuroxime	< 14 years: 15 mg/kg every 12 hours > 14 years: 500 mg every 12 hours	Maximum 1000 mg/day
Cefpodoxime	5 mg/kg every 12 hours	—
Ceftriaxone	50 mg/kg IM or IV once May repeat at 72 hours	Consider particularly for children with severe vomiting or who will not swallow antibiotic liquids
Resistant cases‡
Amoxicillin/clavulanate	< 14 years: 40–45 mg/kg every 12 hours ≥ 14 years: 500 mg every 12 hours	Preferred; dose based on amoxicillin component Use new formulation to limit clavulanate to maximum of 10 mg/kg/day
Ceftriaxone	50 mg/kg IM or IV once a day for 3 days	Can use even if failed on oral cephalosporin Considered if adherence is likely to be poor
Clindamycin	10 to 13 mg/kg every 8 hours	2nd-line alternative, consider using along with a cephalosporin
*Treatment duration is typically 10 days for children < 2 years and 7 days for older children unless otherwise specified. Drugs are given orally unless otherwise specified.
†Cross reactivity of 2nd- and 3rd-generation cephalosporins with penicillin is very low.
‡No improvement after 48 to 72 hours of treatment, or previous resistant infection; amoxicillin used in the previous 30 days; or concurrent purulent conjunctivitis