Pediatric Primary Care Case Studies (87 page)

Your symptom analysis reveals the following information: Sam started with a slight cough and runny nose 4 days ago. The rhinorrhea started with a small amount of clear discharge but has increased over the past 48 hours. Sam had been active and playful despite his symptoms until last night when his fever spiked to 102.2°F (39°C). His mother reports he was up most of the night crying and wanting to be held. He had one ear infection at 8 months of age and his mother is concerned that he may have another one because he is intermittently tugging at his right ear, acting as if it hurts. Ibuprofen has
helped some with the fever and pain. Today Sam has been drinking well and has had several wet diapers, but he is not interested in eating. He has had no vomiting but his stools have been loose for the last 2 days.

What other questions do you need to ask Sam’s mother?

Before answering this question, here is some more information about acute otitis media that you need to consider.

Epidemiology

Acute otitis media (AOM) is the most common bacterial infection in children, accounting for nearly 30 million clinic visits per year and costing over $5 billion in the United States yearly. It is the most frequent reason for childhood antibiotic consumption and outpatient surgery in developed countries (Rovers, Schidler, Zielhuis, & Rosenfeld, 2004). Fifty percent of U.S. infants have had at least one episode of AOM before 6 months of age, and 90% experience at least one episode by age 2 years (Siegel & Bien, 2004). There is an increased incidence in those younger than 2 years, with the peak age of incidence between 6 and 20 months. Males account for just over 50% of all cases.

Otitis media is especially prevalent and more severe among Native American, Inuit, and indigenous Australian children (Kerschner, 2007). Studies in the United States comparing otitis media rates among white and African American children have given conflicting results, but overall findings suggest that race-based difference rates seem most likely attributable to socioeconomic status, access to care, accuracy of diagnosis, and intensity of surveillance rather than race itself (Paradise et al., 1997).

Risk Factors

Age

The highest incidence for AOM is between 6 months and 2 years. Younger children are at increased risk for otitis media due to the relative immaturity of their immune systems. The developing immune systems of young children have less experience with common viruses than do those of adults. Viral infections likely are the direct or indirect cause of most middle ear infections (Kerschner, 2007).

More importantly, in infants and toddlers, the eustachian tube, responsible for draining middle ear secretions to the nasopharynx, is shorter, straighter, and floppier than an adult eustachian tube (Rovers et al., 2004). This straight, more easily closed design does not ventilate the middle ear as effectively, making it more susceptible to swelling, inflammation, and bacterial colonization (Maxson & Yamauchi, 1996).

Socioeconomic Status

Poverty has long been recognized as a major contributing factor in the development and the severity of OM. Recent studies strongly suggest that low
socioeconomic status is one of the most important identifiable risk factors for the development of acute otitis media (Paradise et al., 2007). Crowded conditions, limited hygiene, suboptimal nutrition, limited access to health care, and limited resources for compliance with provider recommendations have all been suggested as playing a role in the relationship between poverty and the development of acute otitis media (Kerschner, 2007).

Secondhand Smoke Exposure

Passive smoke exposure increases the incidence of AOM and otitis media with effusion (OME), and the duration of the middle ear effusion. The precise mechanism remains unknown, but there is sufficient evidence to support a causal relationship between parental smoking and otitis media (U.S. Department of Health and Human Services, 2006). Recent studies suggest that nicotine and other toxins in secondhand smoke may enhance the invasion of bacteria into the middle ear and depress local immune function. Environmental tobacco smoke may cause toxic injury to the epithelium of the nasopharynx resulting in prolonged inflammation and congestion of the upper airways. It may also impair the mucociliary function of the eustachian tube and lead to impaired clearance of the nasopharyngeal airways (Kum-Nji, Meloy, & Herrod, 2006).

Etiology

Streptococcus pneumoniae
, nontypeable
Haemophilus influenzae
, and
Moraxella catarrhalis
remain the leading bacterial pathogens responsible for acute otitis media (American Academy of Pediatrics [AAP], 2004). Viral infections, most commonly respiratory syncytial virus (RSV), influenza, and parainfluenza, are also common pathogens involved in AOM. It is uncertain whether viral infections alone can cause AOM, or whether their role is limited to setting the stage for secondary bacterial infection (Kerschner, 2007). It is suspected that viral co-infection amplifies the inflammatory process and contributes to delayed bacterial clearance (Rovers et al., 2004).

S. pneumoniae
accounts for 25–50% of AOM,
H. influenzae
accounts for approximately 40% of cases, and
M. catarrhalis
is responsible for one eighth of the recognized bacterial otitis media. There is some evidence to suggest that the microbiology of acute otitis media is changing due to the routine use of the heptavalent pneumococcal vaccine, with more cases now attributable to gram-negative and beta lactamase–producing organisms (Block et al., 2004).

Pathophysiology

Dysfunction of the eustachian tube and inflammation are the most important factors in the development of AOM. Commonly, viral upper respiratory infections precede or coincide with AOM. The viral infections induce inflammation and edema in the nasopharynx and eustachian tube, narrowing the eustachian tube lumen. Obstruction of the lumen causes negative pressure to build up, creating a
relative vacuum within the middle ear space. This phenomenon reverses the flow of secretions, pulling fluid from the nasopharynx into the middle ear (Siegel & Bien, 2004). The resulting mucoid medium is ideal for bacterial colonization and overgrowth, stimulating an even greater inflammatory response.

Data for the Diagnosis

Often the diagnosis of acute otitis media is evident by the history and physical examination findings, but, as in all realms of medicine, it is important to generate a differential diagnosis to ensure proper management and counseling for the patients. Viral myringitis and otitis media with effusion (OME) may be mistaken for acute otitis media. In myringitis, characterized by otalgia and an erythematous ear drum, the tympanic membrane is inflamed; however, it is nonbulging and freely mobile on pneumatic otoscopy (Siegel & Bien, 2004). On the other hand, OME is characterized by a poorly mobile, nonbulging TM, indicating the presence of middle ear fluid. In OME, the tympanic membrane lacks the characteristic inflammation that is seen in AOM.

The differential diagnoses also include otitis externa, or swimmer’s ear, which is an inflammation of the external auditory canal or auricle. Presence of a foreign body in the ear canal or impacted cerumen can also present as otalgia, but will typically lack the preceding upper respiratory infection (URI) symptoms and fever that accompany AOM, and will be evident on physical examination. Other diagnoses to consider when patients present with otalgia include local trauma, varicella zoster, herpes simplex, cellulitis or furunculosis of the ear canal, mastoiditis, and perichondritis. Referred pain from dental infections, stomatitis, pharyngitis, tonsillitis, and retropharyngeal abscesses must also be considered but are typically ruled out by physical examination (Sinai & Biggs, 2003).

From the above review, some other information you should obtain includes the following:

•   Is there smoke exposure in the home? (Increased risk for development of AOM)

•   Is the child breastfed? (Protective effect of breastmilk and breastfeeding if continued for at least 4 months)

•   Does the child attend daycare? (Increased risk for development of AOM)

•   Is there a family history of otitis media? (Increased risk for development of AOM with positive family history)

•   Does the child have any speech delays or other developmental concerns? (Concern for conductive hearing loss due to AOM)

•   Has the child been on antibiotics within the last month? (Increased risk for resistant organisms)

•   Does the child have AOM and purulent conjunctivitis? (Nontypeable
H. influenzae)

•   Is there history of otorrhea? (TM perforation or myringotomy tubes)

•   Is there increased pain with traction on pinna? (Otitis externa)

•   Is the external auditory canal erythematous and/or edematous? (Otitis externa)

•   Is there a vesicular exanthem involving the auricle or ear canal? (Varicella zoster, herpes simplex)

Physical Examination

Upon physical examination, Sam is ill appearing and quiet in his mother’s lap. He has thick nasal discharge in both nares. Examination of the left tympanic membrane (TM) reveals a pearly gray tympanic membrane in neutral position. The light reflex and bony structures are clearly visible. Pneumatic otoscopy reveals movement of the left TM. The right tympanic membrane is cloudy, erythematous, and bulging. There are no visible landmarks. On pneumatic otoscopy of the right ear, there is no movement of the tympanic membrane. His oropharynx is moist and without erythema, ulceration, or exudates. Sam’s neck is supple and without lymphadenopathy. His eye, heart, lung, and abdominal examinations are unremarkable.

Making the Diagnosis

The history and physical examination are consistent with the diagnosis of acute otitis media, right ear. Diagnostic criteria for AOM include 1) rapid onset of symptoms, 2) presence of middle ear effusion, and 3) signs and symptoms of middle ear inflammation (AAP, 2004). Fever, irritability, rhinitis, cough, decreased oral intake, trouble sleeping, and tugging at the ears are often associated with AOM but are nonspecific symptoms that can be seen in many childhood illnesses (Rothman, Owens, & Siemel, 2003). It is important to remember that acute otitis media cannot be differentiated from a common viral upper respiratory infection based on symptoms alone.

A bulging, cloudy, immobile tympanic membrane is the most helpful physical finding to clinch the diagnosis (Rothman et al., 2003). Color is not a defining feature of acute otitis media because the infected middle ear may appear red or yellow (Siegel & Bien, 2004). However, a tympanic membrane that is distinctly red, or “hemorrhagic, strongly red or moderately red,” suggests AOM (Rothman et al.).

Detection of middle ear effusion by pneumatic otoscopy is a key element in the diagnosis of acute otitis media (AAP, 2004). Normally, the tympanic membrane is a convex, freely mobile, translucent barrier between the external ear canal and the inner ear. With insufflation, the healthy tympanic membrane moves easily in response to positive or negative pressure (Siegel & Bien, 2004). Normal mobility is evident when positive pressure is applied to the insufflator bulb and the eardrum moves rapidly inward; when the bulb is released, creating negative pressure, the TM moves out. The presence of a middle ear fluid, infectious or otherwise, significantly reduces the mobility of the TM. Evidence of middle ear effusion may also be demonstrated by the presence of purulent fluid in the external auditory canal, indicating a perforated tympanic membrane.

Management

How do you plan to treat Sam’s acute otitis media?