Acute otitis media in children: Clinical manifestations and diagnosis

INTRODUCTION — Acute otitis media (AOM) is a common problem in children and accounts for a large proportion of pediatric antibiotic prescriptions.

The clinical manifestations and diagnosis of AOM in children will be reviewed here. The epidemiology, pathogenesis, treatment, and prevention of AOM in children and AOM in adults are discussed separately.

●(See "Acute otitis media in children: Epidemiology, microbiology, and complications".)

●(See "Acute otitis media in children: Treatment".)

●(See "Acute otitis media in children: Prevention of recurrence".)

●(See "Acute otitis media in adults".)

TERMINOLOGY

●Middle ear effusion (MEE) – Fluid in the middle ear cavity; MEE occurs in both AOM and otitis media with effusion (OME).

●Acute otitis media – Acute bacterial infection of middle ear fluid; also called suppurative otitis media.

●Otitis media with effusion (OME) – Middle ear fluid that is not infected; also called serous, secretory, or nonsuppurative otitis media.

AOM and OME are part of a continuous spectrum; OME frequently precedes the development of AOM or follows its resolution. (See "Otitis media with effusion (serous otitis media) in children: Clinical features and diagnosis", section on 'Clinical features'.)

MIDDLE EAR ANATOMY — The middle ear is a cavity between the external ear canal and the inner ear that contains the ossicular chain (figure 1). The facial nerve traverses the medial wall of the middle ear. The middle ear is contiguous with the Eustachian tube, attic (epitympanum), and mastoid air cells.

The tympanic membrane is divided into four quadrants: a line drawn along the manubrium of the malleus divides the anterior and posterior quadrants, and a line through the umbo divides the superior and inferior quadrants (figure 2). The pars flaccida is the small portion of the tympanic membrane above the lateral process of the malleus; it is thicker and less taut than the rest of the tympanic membrane. The remainder of the tympanic membrane (the pars tensa) is thinner than the pars flaccida and is suspended from the fibrous tympanic annulus.

The normal middle ear is aerated, and the normal tympanic membrane is intact, slightly convex, translucent, and mobile (picture 1).

CLINICAL PRESENTATION

Acute otitis media — Symptoms of AOM in children include ear pain, ear rubbing, hearing loss, and ear drainage. Fever occurs in one- to two-thirds of children with AOM, though temperature >40°C (104°F) is unusual without bacteremia or another focus of infection [1].

Ear pain is the most common complaint and the best predictor of AOM [2-4]. However, ear pain and other ear-related symptoms are not always present [2,3,5]. In a prospective study of 335 consecutive episodes of AOM, ear pain was absent in 17 percent [5]. AOM without complaints of ear pain occurred more frequently in children younger than two years (who may not be able to complain of ear pain) than in older children (25 versus 7 percent). Other causes of ear pain, hearing loss, and otorrhea in children are discussed separately. (See "Evaluation of earache in children" and "Hearing loss in children: Etiology" and "Evaluation of otorrhea (ear discharge) in children".)

Young children with AOM, particularly infants, may present with nonspecific symptoms and signs (eg, fever, fussiness, disturbed or restless sleep, poor feeding/anorexia, vomiting, diarrhea) [3,6,7]. Symptoms of AOM may overlap with those of upper respiratory tract infection without AOM or may be subtle or absent [2,6,8-10]. The lack of specificity of symptoms in young children makes the diagnosis challenging and underscores the importance of otoscopy, which is also challenging in young children.

Complications of AOM — Children with complications of AOM may present with findings related to the complication, including (see "Acute otitis media in children: Epidemiology, microbiology, and complications", section on 'Complications and sequelae') [4,11]:

●Postauricular swelling and protrusion of the auricle (picture 2A-B) are characteristic of mastoiditis. (See "Acute mastoiditis in children: Clinical features and diagnosis", section on 'Clinical features'.)

●Vestibular symptoms (eg, dizziness, vertigo, balance and motor problems) with or without tinnitus or nystagmus may be related to labyrinthitis, mastoiditis, or cholesteatoma. (See "Causes of dizziness and vertigo in children and adolescents", section on 'Otitis media' and "Evaluation of dizziness and vertigo in children and adolescents" and "Cholesteatoma in children", section on 'Clinical features'.)

●Cranial nerve palsies (eg, facial nerve, abducens nerve) may be related to acute mastoiditis, petrositis, cholesteatoma, or intracranial complications. (See "Facial nerve palsy in children", section on 'Otitis media' and "Third cranial nerve (oculomotor nerve) palsy in children" and "Fourth cranial nerve (trochlear nerve) palsy" and "Sixth cranial nerve (abducens nerve) palsy".)

●Meningeal signs, cranial nerve deficits, and/or focal neurologic findings may be related to intracranial complications (eg, meningitis, brain abscess, epidural or subdural abscess, lateral or cavernous sinus thrombosis). These complications are discussed in individual topic reviews. (See "Bacterial meningitis in children older than one month: Clinical features and diagnosis", section on 'Clinical features' and "Pathogenesis, clinical manifestations, and diagnosis of brain abscess" and "Intracranial epidural abscess" and "Septic dural sinus thrombosis".)

OTOSCOPIC EVALUATION — Otoscopic evaluation is necessary for the diagnosis of AOM.

Procedure

●Cerumen removal – Obstructing cerumen must be removed from the external canal to ensure a clear view of the tympanic membrane. Cerumen is most practically and conveniently removed under direct vision. (See "Cerumen", section on 'Cerumen removal'.)

●Equipment

•An otoscope with an adequate light source (eg, a halogen bulb with brightness ≥100 foot-candles [1000 lux]) and fully charged battery [12-14]; a pneumatic otoscope with a round head is preferred because it provides the best seal for pneumatic otoscopy (picture 3).

•Ear specula of various sizes; the largest size that fits comfortably into the cartilaginous portion of the external auditory canal should be used (a 4 mm speculum will work for most children) [13]; the outer diameter of the speculum may be increased by putting a small piece of rubber tubing around the tip [14,15].

•Insufflator bulb and tubing; the pneumatic system should be checked for leaks periodically by occluding the tip of the speculum with a finger and squeezing the rubber bulb to see if resistance is felt [13].

●Assessment of tympanic membrane – Each quadrant of the tympanic membrane (figure 2) should be assessed systematically to evaluate position, mobility, translucency, color, and other findings (eg, air-fluid levels, perforation, retraction pockets, cholesteatoma) [13,16]. Mobility of the tympanic membrane can be assessed with pneumatic otoscopy.

Systematic evaluation of the tympanic membrane and pneumatic otoscopy are challenging, particularly in young children who may not cooperate with the examination.

●Pneumatic otoscopy – Pneumatic otoscopy can be painful in children with AOM. It is not necessary in children with bulging tympanic membranes because all bulging tympanic membranes have decreased or absent mobility. (See 'Tympanic membrane findings' below.)

Pneumatic otoscopy creates positive and negative pressures within the external auditory canal by using the insufflator bulb of the otoscope. Positive pressure is created when the insufflator bulb is compressed and negative pressure when it is released. An airtight seal between the speculum and the external auditory canal is essential.

Mobility of the tympanic membrane is best visualized in the posterosuperior quadrant or pars flaccida, where the tympanic membrane is most compliant (figure 2) [14]. The tympanic membrane moves away from the observer with positive pressure and toward the observer with negative pressure. Mobility is described as normal (movie 1), absent (movie 2), decreased, or increased.

When there is high negative pressure in the middle ear cavity, the tympanic membrane may be maximally retracted and unable to move away from the observer with positive pressure (movie 2). Mobility of a retracted tympanic membrane can be assessed by creating negative pressure in the external auditory canal. The otoscope should be removed from the external canal and the bulb compressed. After the bulb is compressed, the otoscope is reinserted into the external canal. When the seal is secured, the bulb is released, creating negative pressure, which allows the retracted tympanic membrane to move toward the observer into a neutral position.

●Digital otoscopy – Digital otoscopy, which is in more frequent use since 2015, incorporates a high-resolution camera into the otoscope or endoscope to permit photography or videography. Several brands of digital otoscopes are available. None of the devices permits pneumatic otoscopy.

One type of device connects to a smartphone to create a digital otoscope that provides images similar to those viewed through a conventional otoscope; these devices typically use large specula, require cerumen removal, and may be awkward to use as the smartphone functions as the handle of the otoscope.

Another digital otoscope uses a thin speculum to bypass or push through cerumen to provide a view of the tympanic membrane. The recorded images can be viewed on the enlarged otoscope touchscreen or uploaded to a computer for magnification and reviewed by single or multiple observers (including the caregivers). This is one of the main advantages of these devices which allows concurrent observation for instructional and diagnostic purposes of a "still" image to "study."

Digital otoscopic devices address one of the main challenges of the ear examination in young children, which is documentation. One study has shown improved interrater agreement between trainees and supervisors when using the digital otoscope compared with the traditional otoscope [17]. Whether the use of digital otoscopy will improve diagnosis of AOM and reduce unnecessary antibiotics requires additional study [18].

Otoscopy skills, including accurate interpretation of findings, can be improved through training [19,20].

Tympanic membrane findings — In children with AOM, the classic examination findings include a fluid-filled middle ear and tympanic membrane that is bulging, opaque, yellow, or white (picture 4 and picture 5) and has decreased or absent mobility with pneumatic otoscopy, if pneumatic otoscopy is performed [21-23]. However, this constellation of findings is not always present.

●Bulging tympanic membrane – A bulging tympanic membrane is the hallmark of AOM and differentiates AOM from otitis media with effusion (OME) (picture 4) [10,21,23-26]. A bulging tympanic membrane indicates both acute inflammation and middle ear effusion (MEE, and thus decreased or absent mobility).

Bulging is first apparent in the posterosuperior area, where the tympanic membrane is most compliant (figure 2). When the tympanic membrane is bulging, the handle of the malleus is obscured (picture 4) [14]. The tympanic membrane may appear full rather than bulging when there are smaller amounts of infected middle ear fluid.

In a large study correlating examination findings from otoscopy with results from myringotomy (as a diagnostic tool for AOM), the predictive value of a bulging tympanic membrane ranged from 83 to 99 percent [21]. In another study correlating examination findings with diagnosis of AOM by experienced otoscopists, 92 percent of children with AOM had a bulging tympanic membrane compared with none of the children with OME or no effusion [24].

In these studies, AOM was unlikely when the tympanic membrane was in a neutral position (picture 1) or retracted (picture 6) [10,24]. When the tympanic membrane is retracted, the handle of the malleus appears to be shortened, and the lateral process becomes more prominent and seems closer to the otoscope [13,14]. Retraction of the tympanic membrane indicates negative pressure in the middle ear cavity (eg, Eustachian tube dysfunction).

●Acute perforation with purulent otorrhea – Acute perforation with purulent otorrhea establishes the diagnosis of AOM provided that otitis externa is excluded [27]. (See 'Clinical diagnosis' below and "External otitis: Pathogenesis, clinical features, and diagnosis".)

●Decreased or absent mobility – Decreased or absent (movie 2) tympanic membrane mobility is a sign of MEE, provided that the seal is airtight during pneumatic otoscopy [13,28]. Decreased mobility also may occur with myringosclerosis of the tympanic membrane (picture 7).

Decreased or absent mobility cannot be used in isolation to make a diagnosis of AOM because it does not distinguish infected from uninfected middle ear fluid. In a study correlating examination findings with a diagnosis of AOM by experienced otoscopists, decreased mobility of the tympanic membrane was present in all 50 cases of AOM and 23 of 34 cases of OME [24].

Increased mobility of the tympanic membrane is not helpful in the diagnosis of AOM. Increased mobility of an area of the tympanic membrane may occur at the site of a previous perforation or tympanostomy tube or may be caused by atrophy of the tympanic membrane.

●Cloudy or opaque tympanic membrane – The tympanic membrane, or a portion of the tympanic membrane (with an air-fluid level (picture 8)), may appear cloudy or opaque when there is fluid in the middle ear, but this finding does not help differentiate AOM from OME. In a study correlating examination findings with a diagnosis of AOM by experienced otoscopists, the tympanic membrane was opaque in 50 of 50 cases of AOM and 33 of 34 cases of OME [24]. In children with opacification of the tympanic membrane without bulging, experienced otoscopists generally diagnose OME [23,24].

●Color of the tympanic membrane

•A white or pale yellow tympanic membrane usually indicates pus in the middle ear cavity, a sign of AOM (picture 4). Middle ear fluid that is not infected (ie, OME) usually appears amber, gray, or blue (picture 9A-B).

•A red or hemorrhagic tympanic membrane may indicate acute inflammation, but it is nonspecific. Erythema of the tympanic membrane may be caused by vasodilation related to manipulation of the canal (as occurs during removal of cerumen), crying, or high fever. In the crying child, vascular engorgement is limited to the periphery and handle of the malleus (picture 10) [29]. Vessels crossing the tympanic membrane suggest inflammation (picture 4).

Erythema is less important than the position and mobility of the tympanic membrane in the diagnosis of AOM [10,21,24]. In a large study correlating otoscopic findings and AOM, a distinctly red tympanic membrane (defined as hemorrhagic, strongly, or moderately red) in the absence of bulging or impaired mobility predicted a diagnosis of AOM in only 15 percent of cases [21]. In a systematic review, the adjusted likelihood ratio for a distinctly red tympanic membrane was 8.4 (95% CI 6.7-11) and for a slightly red tympanic membrane was 1.4 (95% CI 1.1-1.8) [10].

●Other findings – Other findings may indicate inflammation (acute or chronic), MEE (infected or uninfected), and complications or sequelae of AOM:

•Bullae are caused by inflammation of the tympanic membrane that occurs in association with AOM (picture 11).

•Bubbles or air-fluid levels (picture 8) indicate MEE and are more suggestive of OME than AOM [24]. Air-fluid levels fluctuate with pneumatic otoscopy.

•Myringosclerosis (asymptomatic whitish plaques of calcium and phosphate crystals in the tympanic membrane (picture 7)) may result from chronic middle ear inflammation, perforation, myringotomy with or without tympanostomy tube placement, or trauma. Myringosclerosis moves with the tympanic membrane during pneumatic otoscopy. (See "Otitis media with effusion (serous otitis media) in children: Clinical features and diagnosis", section on 'Complications and sequelae'.)

•Perforation of the tympanic membrane may result from increased middle ear pressure that leads to central ischemia and necrosis.

•Atrophic areas may result from AOM; atrophic areas may have increased mobility.

•Retraction pockets (picture 12) may be sequelae of otitis media and can predispose to the development of cholesteatoma.

•Cholesteatomas are benign growths of desquamated, stratified, squamous epithelium. They may appear as a cyst within the tympanic membrane, greasy white debris, or as a mass (picture 13). Children with cholesteatoma or suspected cholesteatoma should be referred to an otolaryngologist. (See "Cholesteatoma in children".)

TYMPANOMETRY AND ACOUSTIC REFLECTOMETRY — Tympanometry and acoustic reflectometry may be used to confirm middle ear fluid.

●Tympanometry measures the compliance of the tympanic membrane, Eustachian tube function, and middle ear function [30].

●Acoustic reflectometry measures the reflection of sound from the tympanic membrane. A smartphone application that uses acoustic reflectometry to detect middle ear fluid has been developed [31]. In a small study, its accuracy was comparable to that of pneumatic otoscopy and tympanometry, but additional validation is necessary before it can be recommended [32].

Neither tympanometry nor acoustic reflectometry differentiates infected from uninfected middle ear fluid [33,34]. However, if tympanometry and/or acoustic reflectometry are normal, both AOM and OME are unlikely. Tympanometry and acoustic reflectometry are discussed separately. (See "Otitis media with effusion (serous otitis media) in children: Clinical features and diagnosis", section on 'Diagnosis'.)

DIAGNOSIS — Stringent diagnostic criteria are necessary to distinguish AOM from otitis media with effusion (OME). The importance of accurate diagnosis of AOM cannot be overstated. Accurate diagnosis prevents overuse of antibiotics, which leads to the development of resistant organisms [35-37].

Acute otitis media

Clinical diagnosis — The diagnosis of AOM requires middle ear effusion (MEE) and acute signs of middle ear inflammation. Children who have MEE without evidence of acute inflammation have OME. (See 'Otitis media with effusion' below.)

A clinical diagnosis of AOM can be made in children with either [24,27]:

●Bulging of the tympanic membrane (picture 4); distinct fullness or bulging of the tympanic membrane is the most specific and reproducible sign of acute inflammation (picture 4) [10,21,23,24]. Pneumatic otoscopy is not necessary in children with bulging of the tympanic membrane.

●Perforation of the tympanic membrane with acute purulent otorrhea if acute otitis externa has been excluded. (See "External otitis: Pathogenesis, clinical features, and diagnosis".)

Very infrequently, a clinical diagnosis of AOM can be made in children without bulging of the tympanic membrane or acute purulent otorrhea if they have MEE and other signs of acute inflammation (eg, panel A of (picture 5)), although experienced otoscopists rarely make the diagnosis of AOM in the absence of tympanic membrane bulging [23,24].

MEE can be confirmed by otoscopy in children with bubbles or an air-fluid level (picture 8), or two or more of the following: abnormal color (white, yellow, amber, gray, or blue), opacity involving all or part of the tympanic membrane that is not due to myringosclerosis, and impaired mobility (movie 2) [38]. MEE can also be confirmed by tympanometry, acoustic reflectometry, myringotomy, or tympanocentesis; myringotomy and tympanocentesis are rarely performed in the primary care setting [10,36]. (See 'Tympanometry and acoustic reflectometry' above.)

In children with MEE, signs of acute inflammation are necessary to differentiate AOM from OME. Although marked redness of the tympanic membrane is a sign of acute inflammation [38], marked redness of the tympanic membrane without bulging is unusual in AOM [24]. In a large study correlating otoscopic findings with observations made at the time of myringotomy, a distinctly red tympanic membrane in the absence of bulging or impaired mobility had a positive predictive value of only 15 percent for AOM [21]. Nonotoscopic signs and symptoms of inflammation (eg, fever, ear tugging, otalgia) must be accompanied by abnormal otoscopic findings to make a diagnosis of AOM.

Etiologic diagnosis — Tympanocentesis (aspiration of the middle ear fluid) for culture or other microbiologic studies is required for etiologic diagnosis. Etiologic diagnosis is not necessary in most cases of AOM because antimicrobial therapy is chosen empirically. Tympanocentesis for etiologic diagnosis is warranted if the child appears toxic, is immunocompromised, or has failed previous courses of antibiotic therapy. (See "Acute otitis media in children: Treatment", section on 'Treatment failure'.)

Otitis-conjunctivitis — When AOM occurs with purulent conjunctivitis, it is called otitis-conjunctivitis (or conjunctivitis-otitis) syndrome [39-42]. Otitis-conjunctivitis syndrome is usually caused by nontypeable Haemophilus influenzae, although it can be caused by other organisms [42-44].

In a series of 124 patients with otitis-conjunctivitis syndrome, 50 percent were younger than two years [41]. The ear pain typically began on the same day as, or within three days following, onset of the ophthalmologic symptoms.

Bullous myringitis — Bullous myringitis (inflammation and bullae of the tympanic membrane (picture 11)) occurs in association with AOM. The viral and bacterial pathogens that cause bullous myringitis are similar to those that cause AOM without bullae [45-50].

Bullous myringitis occurs in approximately 5 percent of cases of AOM in children younger than two years [51]. Children with bullous myringitis usually have more pain at the time of diagnosis than children without bullous myringitis [52].

The treatment and prognosis for bullous myringitis are the same as for AOM without bullae. (See "Acute otitis media in children: Treatment".)

DIFFERENTIAL DIAGNOSIS — The main consideration in the differential diagnosis of AOM is otitis media with effusion (OME).

Otitis media with effusion — Middle ear effusion with decreased mobility and opacification or cloudiness of the tympanic membrane occurs in both AOM and OME. Although the distinction between AOM and OME may be difficult because they are part of a continuous spectrum, other otoscopic findings can be helpful [13]. (See 'Otoscopic evaluation' above.)

●In AOM, the tympanic membrane is usually bulging and is typically white or pale yellow; pus may be seen behind it (picture 4). Other findings associated with AOM include a perforation with purulent otorrhea or bullae (picture 11).

●In OME, the tympanic membrane may be retracted (picture 6) or in the neutral position and is typically amber, gray, or blue (picture 9A-B); bubbles or an air-fluid level (with clear/serous fluid) may be seen behind it (picture 8).

Other conditions — Other conditions share some of the otoscopic and nonotoscopic features of AOM, but the history and physical examination should readily distinguish these conditions from AOM. (See "External otitis: Pathogenesis, clinical features, and diagnosis".)

●Redness of tympanic membrane – Redness of the tympanic membrane may be caused by vascular engorgement (picture 10) due to crying, high fever, upper respiratory infection with congestion and inflammation of the mucosa lining the entire respiratory tract, trauma, and/or cerumen removal.

●Decreased or absent mobility of the tympanic membrane – Conditions other than AOM and OME that cause decreased or absent mobility of the tympanic membrane include myringosclerosis (picture 6) and high negative pressure within the middle ear cavity.

●Ear pain – Ear pain may be caused by otitis externa, ear trauma, throat infections, foreign body, or temporomandibular joint syndrome. (See "Evaluation of earache in children".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Acute otitis media, otitis media with effusion, and external otitis".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient education" and the keyword[s] of interest.)

●Basics topic (see "Patient education: Ear infections in children (The Basics)")

●Beyond the Basics topic (see "Patient education: Ear infections (otitis media) in children (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Terminology – Acute otitis media (AOM) is defined by acute bacterial infection of middle ear fluid; it must be distinguished from otitis media with effusion (OME), which is defined by middle ear fluid that is not infected. (See 'Terminology' above.)

●Clinical presentation – Symptoms of AOM in children include ear pain, ear rubbing, hearing loss, ear drainage, and low-grade fever. Ear pain is the most common complaint, but it is not always present. Young children with AOM may present with nonspecific symptoms (eg, fever, fussiness, disturbed or restless sleep, poor feeding, vomiting, diarrhea). (See 'Clinical presentation' above.)

Children with complications of AOM may present with findings related to the complication (eg, postauricular swelling and protrusion of the auricle, vestibular symptoms, cranial nerve deficits, meningeal signs, focal neurologic findings). (See 'Complications of AOM' above.)

●Examination – Otoscopic evaluation is necessary for the diagnosis of AOM. Each quadrant of the tympanic membrane (figure 2) should be assessed to evaluate position, mobility, translucency, color, and other findings. A bulging tympanic membrane (picture 4) is the hallmark of AOM, and differentiates AOM from OME (table 1). (See 'Otoscopic evaluation' above.)

●Diagnosis – A clinical diagnosis of AOM can be made in children with either a bulging tympanic membrane (picture 4) or perforated tympanic membrane and acute purulent otorrhea if otitis externa has been excluded. (See 'Clinical diagnosis' above.)

Very infrequently, a clinical diagnosis of AOM can be made in children without bulging of the tympanic membrane or acute purulent otorrhea if they have middle ear effusion and other definitive signs of acute inflammation (eg, panel A of (picture 5)). (See 'Clinical diagnosis' above.)

Etiologic diagnosis is not necessary in most cases of AOM because antimicrobial therapy is chosen empirically. Tympanocentesis for etiologic diagnosis is warranted if the child appears toxic, is immunocompromised, or has failed previous courses of antibiotic therapy. (See 'Etiologic diagnosis' above.)

●Differential diagnosis – The main consideration in the differential diagnosis of AOM is OME. In AOM, the tympanic membrane is usually bulging and is typically white or pale yellow; pus may be seen behind it (picture 4). In OME the tympanic membrane may be retracted (picture 6) or in the neutral position and is typically amber, gray, or blue (picture 9A-B); bubbles or an air-fluid level may be seen behind it (picture 8). (See 'Differential diagnosis' above.)