Acute otitis media in children: Epidemiology, pathogenesis, clinical manifestations, and complications

INTRODUCTION

Acute otitis media (AOM) is the most frequent diagnosis in sick children visiting physicians' offices. In 2000, it was estimated that annual expenditures for the diagnosis of otitis media totaled approximately $5 billion in the United States; 40 percent of these costs were for care of children between the ages of one and three years [1]. Analysis of data from a 1992 national survey indicated that 30 percent of all antibiotic prescriptions for children were for the treatment of otitis media [2].

Although AOM occurs at all ages, the disease, defined by the presence of fluid in the middle ear accompanied by acute signs of illness and signs or symptoms of middle ear inflammation, is most prevalent in infancy. Fluid may persist for weeks to months after the onset of signs of AOM despite treatment with appropriate antimicrobial agents. Whenever fluid fills the middle ear space, there is some loss of hearing that may lead to problems of development of speech, language, and cognitive abilities in the child. In developing countries, suppurative infections, including mastoiditis and meningitis, remain important complications of AOM [3]. (See "Etiology of hearing impairment in children".)

The epidemiology, pathogenesis, and complications of AOM will be reviewed here. The diagnosis, treatment, and prevention of AOM, otitis media with effusion, external otitis, and malignant external otitis are discussed separately. (See "Acute otitis media in children: Diagnosis" and "Acute otitis media in children: Treatment" and "Acute otitis media in children: Prevention of recurrence" and "Otitis media with effusion (serous otitis media) in children".)

EPIDEMIOLOGY

Incidence — Between 60 and 80 percent of infants have at least one episode of AOM by one year of age, and 80 to 90 percent by two to three years [4,5]. The highest incidence of AOM occurs between 6 and 24 months of age in the United States. Subsequently, the incidence declines with age except for a limited reversal of the downward trend between five and six years of age, the time of school entry. AOM is infrequent in school-age children, adolescents, and adults, but the bacteriology and therapy are similar to those in infants and children. It is slightly more common in boys than girls [4,5]. The following data indicate the importance of otitis media in infancy and childhood:

• Boston children had an average of 1.2 and 1.1 episodes of AOM in the first and second years of life, respectively [4].
• The number of office visits with a principal diagnosis of otitis media in the United States increased from 9.5 to 24.5 million visits between 1975 and 1990 [6].
• Middle ear disease was responsible for approximately one-third of office visits for illness in each of the first five years of life [7].
• In a study of Pittsburgh-area infants, the mean number of days of antimicrobial therapy for otitis media was 41.9 and 48.6 for the first and second years of life, respectively; infants received antimicrobial therapy for other reasons for a mean of only 1.9 and 4.1 days during these same years [5].
• Placement of tympanostomy tubes is second only to circumcision as the most frequent surgical procedure in infants. The procedure is performed for children with persistent middle ear effusion or severe and recurrent episodes of AOM. The percentage of infants undergoing the procedure was 1.8 and 4.2 percent in the first and second years of life in Pittsburgh [5]. A similar proportion of Boston children also had tympanostomy tube placement, 1.5 and 5.7 percent among children with at least one episode of AOM in the first and second years of life, respectively [8].