Introduction 40 49 35 35 1 54 Fig. 1 a b c  This overview summarizes the main new findings about AOM and OME which are in accordance with some basic well-known but sometimes forgotten data and facts, with particular emphasis on the vulnerability of young children below the age of 2 years. Aetiopathogenesis Role of the eustachian tube 2 5 35 P 2 Fig. 2 NP ET TVP ME MAST TM EC  5 3 4 16 Fig. 3 5  Fig. 4 The tympanic membrane forms the lateral wall of the box-shaped middle ear. The function of the eustachian tube is to equilibrate middle ear pressure with that in the nasopharynx. Bacteria and viruses resident in the nasopharynx may reach the middle ear during pressure equilibration. One-third of the middle ear mucosa and the entire eustachian tube are lined with mucociliary epithelium to transport bacteria from the middle ear back to the nasopharynx. Air from the middle ear enters the mastoid air cells by way of the aditus  In other words, the first episode of AOM determines the evolution and the recurrences because of the associated acute inflammation involving also the ET. Role of viruses and bacteria Viruses 2 50 21 18 32 33 41 50 53 64 Bacteria 35 Haemophilus influenzae Streptococcus pneumoniae 27 28 51 55 58 Haemophilus influenzae 4 Streptococcus pneumoniae Haemophilus influenzae Moraxella catarrhalis 21 23 28 Streptococcus pneumoniae 58 27 11 14 Bacteria and viruses 8 12 Other risk factors The immaturity of the immune system of young children makes them incapable of killing encapsulated bacteria. This, along with the ET dysfunction, explains the long-lasting course of AOM as well as the high recurrence rate. 37 38 37 60 Complications: mastoiditis 65 22 4 Treatment General considerations 13 45 15 35 27 39 Treatment of AOM 1 26 31 10 52 Table 1 Guidelines for treatment of AOM Episode Signs or symptoms Treatment or approach Children <2 years of age First episode  Amoxicillin 90 mg/kg per day for at least 10 days according to the bacterial resistance   Weekly follow-up by tympanometry and pneumo-otoscopy Recurrent episode With redness and bulging tympanum Amoxicillin or amoxicillin 90 mg/kg per day + clavulanic acid 6.4 mg/kg per day according to bacterial resistance  Without bulging “Wait and see” approach Children >2 years of age  With redness and bulging tympanum or otorrhoea Same treatment as “recurrent episode”  Without evident bulging tympanum “Wait and see” approach Streptococcus pneumoniae 57 61 3 Haemophilus influenzae 9 Moraxella catarrhalis 42 The duration of the antibiotic treatment is a matter of discussion. For children less than 2 years of age, a 10-day course is reasonable. Pneumo-otoscopy and tympanometry can help to appreciate the permeability of the ET. Careful follow-up is necessary. 28 51 22 36 Treatment of OME: tympanostomy tubes? 1 2 43 Table 2 SMZ TMP Indication Approach Treatment Without deafness “Watchful waiting” approach  With deafness After 6 weeks-2 months in children ≥2 years Amoxicillin 90 mg/kg per day or amoxicillin 90 mg/kg per day + clavulanic acid 6.4 mg/kg per day for 10 days according to the results of the bacterial resistance   No swimming Recurrent OME or OME of long duration  Azithromycin 10 mg/kg per day, 3 days/week for 4 weeks   Cotrimoxazole 30 mg SMZ + 6 mg TMP/kg per day according to the results of the bacterial resistance   Adenoidectomy in children ≥3 years of age with nasopharyngeal obstruction and recurrent adenoiditis   No swimming 38 34 37 63 24 25 46 48 30 1 Watchful waiting for 3–6 months in the winter period seems advisable in children with mild hearing deficit. 45 Vaccination 6 62 56 Streptococcus pneumoniae Haemophilus influenzae 20 59 7 Infants and prematures 17 19 29