John: Hello, I'm John Hilton, editor of the Cochrane Editorial unit. June 2016 saw the updating of the Cochrane review on the effects of antibiotics for children with otitis media with effusion. We asked lead author, Roderick Venekamp, University Medical Center in Utrecht, The Netherlands, to tell us what they found.

Roderick: Otitis media with effusion, also called “glue ear” is one of the most common diseases of early childhood. It is characterised by an accumulation of fluid in the middle ear behind an intact tympanic membrane without the symptoms or signs of an acute infection. Its consequences vary enormously. In most cases, otitis media with effusion causes mild hearing impairment of short duration. However, when experienced in early life and when episodes of bilateral otitis media with effusion persist or recur, the associated hearing loss may be significant and can have a negative impact on speech development and behaviour.
Since most cases of otitis media with effusion will resolve spontaneously, only children with persistent middle ear effusion and associated hearing loss potentially require treatment. The rationale for using antibiotics in otitis media with effusion is the potential bacterial origin of the disease; a bacterial pathogen is identified in the middle ear fluid of approximately one in three children with otitis media with effusion. Successful eradication of bacteria may promote faster resolution of middle ear fluid and prevention of secondary complications. However, not all cases are of bacterial origin and therefore the potential benefits of antibiotics need to be balanced both against the well-recognised adverse effects and the emergence of antimicrobial resistance.
We assessed the benefits and harms of oral antibiotics in children with otitis media with effusion and identified 25 trials. However, 2 trials did not report on any of the outcomes of interest, leaving 23 trials, involving over 3000 children, covering a range of antibiotics, participants, outcome measures and time points for evaluation.
We found moderate quality evidence from six trials, involving 484 children, that children treated with oral antibiotics are more likely to have complete resolution of otitis media with effusion at 2 to 3 months after randomisation than those allocated to control treatment. The number needed to treat to benefit was 5. However, we also found low-quality evidence that children treated with antibiotics are more likely to experience adverse events. The number needed to treat to harm was 20.
Regarding secondary outcomes, we found low to moderate quality evidence from five meta-analyses, including between 2 and 14 trials, that children treated with oral antibiotics are more likely to have complete resolution of otitis media with effusion at any time point than those allocated to control treatment. The time periods ranged from 10 to 14 days to six months and numbers needed to treat ranged from 3 to 7.
The evidence on other relevant secondary outcomes was limited. Only two trials, involving 849 children, reported on hearing levels at 2 to 4 weeks and found conflicting results. None of the trials reported data on speech, language and cognitive development or quality of life. Low quality evidence indicated that oral antibiotics were not associated with a decrease in the rate of ventilation tube insertion or in tympanic membrane perforations.
In summary, our review presents evidence of both benefits and harms associated with the use of oral antibiotics to treat children with otitis media with effusion. Importantly, the impact of oral antibiotics on short-term hearing is uncertain and low quality evidence did not show that oral antibiotics were associated with fewer ventilation tube insertions. Furthermore, we found no data on the impact of antibiotics on other important outcomes such as speech, language and cognitive development or quality of life. Even in situations where clear and relevant benefits of oral antibiotics have been demonstrated, these must always be carefully balanced against adverse effects and the emergence of antimicrobial resistance.

John: If you’d like to read more about the available trials and the findings of Roderick’s review, you can find it online at Cochrane Library dot com, with a simple search for ‘antibiotics for glue ear’.