Acute Otitis Media and Group A Streptococcal Pharyngitis: A Review for the General Pediatric Practitioner

Background

AOM is cited as the most common reason for physician office visits for children and is a leading diagnosis in pediatric emergency departments.³ Almost one-half of all children experience AOM by their first birthday and up to 83% will have one or more episodes by age 3 years.^5,6 Most infections occur between age 6 and 24 months with a peak age between 9 and 15 months. Cost estimates range from $2 to $5 billion per year related to health care charges, antibiotic prescriptions, and lost wages for parents/caregivers.⁷

Pathogenesis

A viral upper respiratory infection (URI) precedes almost all episodes of AOM, and this diagnosis can be considered a secondary infection. The general pathogenesis involves mucous production leading to eustachian tube inflammation and dysfunction in the setting of a viral URI, the more horizontal orientation of the eustachian tube of the young child, and insufficient drainage of fluid resulting in development of a middle ear effusion (MEE). This accumulation of sterile fluid in the middle ear space is commonly referred to as otitis media with effusion (OME), which is a confusing term because there is not necessarily any inflammation (“otitis”). If microbes from the nasopharynx infect this fluid, the inflammatory condition of AOM develops. The three most common bacterial pathogens—Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis—have not changed over the past several decades, although the relative proportions have changed (decrease in S. pneumoniae, increase in nontypeable H. influenzae) with the routine administration of the conjugated pneumococcal vaccine.^8,9

Diagnosis

The diagnosis of AOM seems like it should be relatively straightforward, but unfortunately that is not the case in general practice. Parents/caregivers use symptoms to decide if they should call or come in for a visit, whereas the medical provider relies on direct visualization of the tympanic membrane (TM). There are many overlapping symptoms such as a preceding URI, complaints of ear pain (otalgia), or perceived ear pain (excessive crying, poor sleep, poking/tugging at an ear). These reported symptoms do not reliably differentiate the presence or absence of AOM in the setting of a viral URI. Clinical history alone is poorly predictive in younger children, reinforcing the idea that this is a visual diagnosis and not one that can be made on history alone.

The 2004 AAP guidelines included diagnostic criteria of an abrupt onset of illness with the presence of MEE, and signs and symptoms of middle ear inflammation.¹⁰ These were updated (and simplified) in the 2013 AAP guidelines emphasizing “stringent otoscopic diagnostic criteria as the basis for management decisions.¹” (Figure 1).

Figure 1. Diagnostic criteria for acute otitis media (AOM). TM, tympanic membrane.

The pneumatic otoscope is the “standard tool used in diagnosis otitis media” and the AAP guidelines stress the “utmost importance for clinicians to become proficient in distinguishing normal middle ear status from OME or AOM.”¹ The TM can be described in terms of color (hemorrhagic, significantly red, slightly red, normal), position (bulging, retracted, normal), translucency, presence or absence of landmarks (cone of light, auditory ossicles), and mobility (distinctly impaired/immobile, slightly impaired, normal mobility). All of these can be helpful in increasing the diagnostic accuracy, but the best predictor for AOM (ie, recovery of a bacterial pathogen from the middle ear space) is moderate to severe bulging of the TM.¹¹

There are many challenges related to direct visualization of the TM. Cerumen commonly blocks some or all of the TM, so pediatric practitioners need to become proficient in removal techniques. Patients can be difficult to examine due to age-appropriate fears or inability to hold still. The idealized photographs appearing in textbooks and journals often seem a far cry from the moving target in the crying, wiggling child. Enlisting the aid of a parent/caregiver or other member of the care team in proper holding techniques for both comfort (of the child) and safety (especially during removal of cerumen) is key. Additionally, many providers neglect to assess mobility of the TM, which can limit accuracy of diagnosis.¹² Getting a sufficient seal can be accomplished through use of commercially available soft rubber or latex sleeves/gaskets applied over the midportion of the speculum. Restraint of the child long enough for insufflation is also important. Pneumatic otoscopy is a learned skill and should be incorporated into training as practice improves proficiency.¹³ Other examination aids include tympanometry and acoustic reflectometry. Both can increase diagnostic accuracy, but neither is a replacement for otoscopy.

Management

Historical features, including the age of the child, severity of symptoms (including presence or absence of fevers), recent (within 30 days) use of antibiotics, associated symptoms (eg, purulent conjunctivitis), and allergies are all important considerations when determining appropriate management of AOM if diagnosed on otoscopy. In essence, asking the right questions before the physical examination will help determine management.

Appropriate management (treatment) of AOM includes analgesia, education, antibiotics, and the option (for some) for observation. The 2004 and 2013 AAP guidelines^1,10 emphasize the importance of appropriate analgesia. Weight-appropriate dosages of acetaminophen (15 mg/kg per dose) and ibuprofen (10 mg/kg per dose) are the only things proven to reliably provide relief of symptoms in the first 24 to 48 hours after diagnosis (antibiotics do not typically work that fast to reduce the inflammation or pressure). Benzocaine-containing products, the most commonly prescribed topical analgesic, were removed from the market due to the potential to cause methemoglobinemia. Other agents such as topical lidocaine may be helpful, but more studies are needed to validate safe and effective topical agents. Neglecting to address the pain can lead to unnecessary suffering for the child and worry for the caregiver.

Education is an important tool for pediatric providers. Informing families about strategies to prevent AOM (eg, avoidance of environmental smoke exposure and bottle propping, the protective effects of breast-feeding and immunizations), recognition of the signs and symptoms, when to seek care, and appropriate home care measures can all increase satisfaction and decrease heath care utilization.¹⁴ There are increasing roles for shared decision-making with caregivers in determining the appropriate management strategies.^15,16

Antibiotics have been the mainstay of therapy for AOM for decades. Changes in the microbiology, as described previously, and research on duration of therapy in different age groups and clinical situations have shaped current guidelines. First-line therapy, according to the 2013 AAP guideline,¹ remains amoxicillin at the higher dosage (80–90 mg/kg/day divided twice daily for resistant strains of pneumococcus), although declining rates of these resistant strains (due to vaccination) may ultimately see a return to lower effective dosages. There is some evidence for using amoxicillin/clavulanic acid (90 mg/kg/day divided twice daily) as first-line therapy but this has not led yet to changes in the AAP guideline, which does outline circumstances in which amoxicillin would not be recommended as first-line therapy (concurrent purulent conjunctivitis/otitis-conjunctivitis, use of amoxicillin within the past 30 days, or a history of recurrent AOM unresponsive to amoxicillin).^1,17–20 Other special considerations for choice of antibiotics (if indicated) include allergies (most will tolerate third-generation cephalosporin if nonanaphylaxis penicillin or amoxicillin allergy, consideration of clindamycin or azithromycin but neither is ideal due to poor coverage of H. influenzae for clindamycin and S. pneumoniae for azithromycin), treatment failures, vomiting (ceftriaxone intramuscularly [IM]), and what not to use (eg, fluoroquinolones, penicillin, trimethoprim/sulfa). Duration of therapy depends on age, severity of symptoms, and recent antibiotic use. Traditionally a 10-day course (other than with azithromycin) has been recommended but the 2013 guidelines¹⁰ suggest 10 days for children younger than age 2 years, 7 days for children age 2 to 5 years, and 5 to 7 days for children older than age 6 years.

Observation without antibiotics has become a viable option for many children diagnosed with AOM to limit antimicrobials to those most likely to benefit. The guidelines¹ cite “in systematic reviews of studies that compare antibiotic therapy for AOM with placebo, a consistent finding has been the overall favorable natural history in control groups” and concluded that “observation as initial management for AOM in properly selected children does not increase the suppurative complications, provided that follow-up is ensured and a rescue antibiotic prescription is given for persistent or worsening symptoms.” Provision of a wait-and-see prescription (WASP) or safety-net-antibiotic-prescription (SNAP) is a successful strategy to prevent unnecessary antibiotic use when coupled with appropriate education around home-care measures and instructions to fill the prescription if the child fails to improve or worsens within 48 to 72 hours of diagnosis. Fill rates for WASP/SNAP prescriptions are reported at approximately only one-third.^21,22Figure 2 summarizes management decisions including when observation is appropriate.

Figure 2. Flow diagram of a management decision based on the American Academy of Pediatrics guidelines. Abx, antibiotics; SNAP, safety-net-antibiotic-prescription; Temp, temperature; WASP, wait-and-see prescription.

Prophylactic antibiotics are ineffective and not recommended. Persistence of MEE is common (60%–70% at 2 weeks, 40% at 1 month, and 10%–25% at 3 months). Surgical intervention could be considered for a child with 3 or more separate AOM episodes in the past 6 months or 4 or more episodes in the past year with at least 1 in the past 6 months.¹

In summary of the AAP guidelines,¹ key practice-altering points are (1) appropriate diagnosis of AOM (pneumatic otoscopy helps); (2) relieve pain; (3) options for observation are expanded (WASP/SNAP) (this can make a difference in antibiotic overuse and resistance); (4) antibiotics duration is based on age; and (5) amoxicillin is still first-line choice for most children needing an antibiotic for AOM.

Background

Sore throat (pharyngitis) is one of the most common complaints in pediatric patients and is responsible for over 7 million outpatient visits per year.²³ The most common bacterial cause, GAS, accounts for 15% to 36% of cases with an estimated societal cost in the United States of $224 to $539 million per year (inclusive of medical and nonmedical costs).²³ Pharyngitis is also cited as one of the more common indications for antibiotics and is a target for efforts at reducing unnecessary prescribing.^3,4 Although the presenting symptoms including sore throat, fevers, and difficulty swallowing are bothersome, potential complications, both suppurative (eg, peritonsillar abscess, cervical lymphadenitis) and nonsuppurative (acute rheumatic fever and poststreptococcal glomerulonephritis) are the major concerns of health care providers.²⁴ In recent decades, the rates of acute rheumatic fever in the US have been low and the emphasis of guidelines has focused on accurate diagnosis and on limiting antibiotics to narrow-spectrum coverage and only when absolutely indicated.²

Other bacteria, including Neisseria gonorrheae, Mycoplasma pneumoniae, Fusobacterium necrophorum, and Group C streptococcus, may be identified in certain patient populations and in some situations require antimicrobial treatment, but GAS is the only common cause of pharyngitis warranting antibiotic therapy.²⁵

Viruses account for many cases of sore throat in children and adolescents. Common viruses including influenza, rhinovirus, adenovirus, respiratory syncytial virus, enterovirus, and Epstein-Barr virus frequently cause sore throat. Differentiating between viral and nonviral causes requires awareness of key differentiating features on history and physical examination because signs and symptoms overlap broadly.

Diagnosis

GAS primarily affects children age 5 to 15 years with peak incidence during winter and early spring. Most present with a sudden onset of sore throat, pain with swallowing, and fever. In children, there are also variable presentations of headache, nausea, vomiting, and abdominal pain. There are certain signs and symptoms that increase the probability of GAS, including scarlatiniform rash, palatal petechiae, pharyngeal exudate, vomiting, and tender cervical lymph nodes.²⁶ The presence of signs or symptoms more commonly associated with viruses (conjunctivitis, cough, hoarseness, rhinorrhea, anterior stomatitis, viral exanthem, or diarrhea) are negatively associated (particularly cough) with the finding of GAS. Incorporating epidemiologic and clinical data into scoring systems may decrease inappropriate testing, increase accuracy of diagnosis, and ultimately lead to improved outcomes.^27,28 The greatest utility of these scoring systems in children is determination of which patients to test and not to test for treatment decisions. Despite clear guidelines, there is still considerable variability in the diagnostic approach and treatment decisions of primary care physicians.²⁹ Simply, only those patients that have symptoms consistent with GAS pharyngitis should be tested. This is important because 15% to 20% of children may be asymptomatic carriers and indiscriminate testing will lead to treatment with unnecessary antibiotics.²

The gold standard for detection of GAS pharyngitis has been culture of a throat swab on a blood agar plate monitored for 24 to 48 hours. Rapid antigen detection tests (RADT) have been developed as well as polymerase chain reaction (PCR) based testing, which can cut down on the time to diagnosis. The RADT have high specificity (positive test = true positive) but many have low enough sensitivity to warrant recommendations for back-up culture testing in the pediatric population.³⁰ PCR-based testing has demonstrated sufficient sensitivity and specificity to obviate the need for back-up culture.³¹ Serology testing (eg, anti-streptolysin or anti-DNase B) does not have a role in the initial diagnosis as positive results during an acute illness are typically representative of a past infection.

Management

GAS pharyngitis has been described as a self-limited illness in many patients, but treatment does have benefits beyond prevention of the rare complication of acute rheumatic fever. Patients treated with an appropriate antibiotic for GAS have symptomatic improvement sooner than those who are untreated.³² The duration of contagiousness is shortened significantly by treatment with antibiotics, which can permit return to daycare, school, or work sooner and limit spread throughout homes and communities.³³ The IDSA guidelines recommend, in the patient who is not allergic, penicillin (oral of IM) or amoxicillin (oral) as the treatments of choice due to the narrow spectrum of activity and 100% susceptibility in vitro of GAS to beta-lactams. Apparent treatment failures in the clinical setting are typically attributed to insufficient compliance, chronic carrier status, co-infection with other organisms, or reinfection. There are strategies, including once daily amoxicillin (50 mg/kg, maximum 1,000 mg) and timing of administration of antibiotics (before 5pm), that may improve compliance and speed safe return to school for children.^34,35 Alternative treatments are available for children with antibiotic allergy (eg, cephalexin, clindamycin, azithromycin). Dosing charts can be found in the IDSA guidelines.²

Chronic (asymptomatic) GAS carriage can persist for months but the risk for transmission to others is minimal and there is no risk of developing long-term sequela. Asymptomatic children carrying GAS do not generally require antimicrobial therapy, but treatment recommendations exist for eradication of carriage in special circumstances.² For children with repeated and frequent episodes of sore throat with positive testing, practitioners should evaluate the clinical findings, exposures, and response to treatment to determine if the patient is a carrier presenting with frequent viral illnesses. For these children, testing can be done when asymptomatic and, if positive, carrier status is confirmed. If a child tests positive, is treated (and compliant), and has improved symptoms, but returns to care relatively soon with new symptoms consistent with GAS pharyngitis, the child should be evaluated for a possible new infection. Tonsillectomy is not routinely recommended solely to decrease the frequency of GAS pharyngitis. In those with a history of rheumatic fever there is a high risk for recurrence, and prevention of recurrent episodes involves continuous prophylaxis (penicillin) twice daily (oral) or monthly (IM).²⁴