What causes acute otitis media?

The most common pathogens of acute otitis media are Streptococcus pneumoniae (pneumococcus) and Haemophilus influenzae (hemophilus influenzae). Viruses, primarily respiratory syncytial virus and Chlamydia pneumoniae, also play a role.

Pneumococcus and Haemophilus influenzae are characterized by high sensitivity to beta-lactams and cephalosporins, but 35% of all pneumococci and 18% of Haemophilus influenzae are resistant to co-trimoxazole.

Pathogens of acute otitis media in children

Exciter	%
H. influenzae	37.8
S. pneumoniae	30.0
S.pyogenes	5.6
S. aureus	3.3
Other	2,2
M. calarrhalis	1,1
H. influenzae + S. pneumoniae	7.8

Sensitivity of S. pneumoniae and H. influenzae to antibacterial drugs

Antibiotic	Sensitivity of S. pneumoniae	Sensitivity of H. influenzae
Penicillin	97.1	-
Ampicillin	97.1	97.6
Amoxicillin/clavunate	100	100
Cefaclor	100	97.6
Cefuroxime	100	100
Ceftriaxone	100	100
Erythromycin	97.1	-
Azithromycin	97.1	100
Co-trimoxazole	64.6	82.3

Boys are more susceptible to acute otitis media. The highest incidence

S.pyogenes	5.6
S. aureus	3.3
Other	2,2
M. calarrhalis	1,1

It has been proven that inflammation of the middle ear is more common in children sleeping on their stomachs than in those sleeping on their backs. Children attending children's groups have a higher incidence of acute otitis media.

Local prerequisites that contribute to the development of acute otitis media include the characteristics of the auditory tube: in children it is short, wider than in adults, straighter, located horizontally, the epithelium (cylindrical) is not yet sufficiently developed, this contributes to stagnation in the tympanic cavity. After birth, loose, vascular-rich connective tissue (the so-called myxoid) is still preserved in the tympanic cavity for some time - a good nutrient medium for the growth of microorganisms. In the nasopharynx of infants, microcirculation disorders are often observed. In combination with the excessive proliferation of lymphoid tissue typical for childhood, the significantly higher frequency of acute otitis media in children (compared to adults) becomes understandable.

The main cause of acute catarrhal otitis media is dysfunction of the auditory (Eustachian) tube, most often associated with acute edema of its mucous membrane.

Among the causes of latent otitis media, it should be noted first of all that it is more common in infancy and is associated with general diseases (viral infection, sepsis, diseases of the bronchopulmonary system and digestive tract), general developmental disorders (prematurity, rickets, artificial feeding, hypotrophy), and allergies.

The causes of recurrent otitis media, sometimes they develop up to 5-8 times a year, can be local and general. The latter include frequent pneumonia, digestive and nutritional disorders, allergies, etc. Local causes are enlarged adenoid vegetations, nasal polyps, sinusitis, hypertrophy of the nasal conchae and palatine tonsils.

Recently, pediatricians' interest in this disease has grown significantly. This is explained by advances in clinical microbiology, new data on the pharmacodynamics of antibiotics in children with otitis media.

Pathogenesis of acute otitis media

There is a classic pattern of acute otitis media. It includes three stages: the first is the initial development of the process, the second is after perforation, and the third is recovery. Each of them lasts about a week. At the first stage, pain, high temperature, hearing loss, hyperemia of the eardrum, general intoxication, and a reaction from the periosteum of the mastoid process appear. At the second stage, after perforation, the symptoms change: pain spontaneously decreases, temperature and intoxication decrease, discharge from the ear appears, perforation of the eardrum is detected during otoscopy, and hearing loss remains at the same level. At the third stage, the temperature normalizes, intoxication disappears, pain is absent, discharge stops, perforation heals, and hearing is restored.

Acute inflammation of the middle ear can occur in two forms: catarrhal and purulent. The first disease is known as "catarrhal otitis media".

Acute catarrhal inflammation of the middle ear can be prolonged and become chronic. This is due to the delay in the evacuation of secretion from the tympanic cavity. The main reason for the transition to a chronic process in childhood is pathology of the nasopharynx, primarily hypertrophy of the nasopharyngeal tonsil (adenoids). Thus, if it is not possible to restore hearing with simple procedures, adenotomy is performed, and sometimes shunting of the tympanic cavity.