On 2014 Dec 18, CREBP Journal Club commented:

Interestingly, recurrent acute otitis media (AOM) occurred more often in children originally treated with amoxicillin. However, the corresponding confidence intervals are wide and the results should be interpreted with caution. It is necessary to conduct similar long term follow-up studies to gain more knowledge about the long term effect and possible harms of antibiotic treatment. The authors identified possible confounders such as sex, allergy, and history of recurrent AOM. It might have been relevant to ask the parents “Has your child had antibiotics since after the trial”, and taken this possible confounder into account as well. The article does not give any information on subsequent antibiotic use after the first six months of the post-trial follow-up period. Sensitivity analysis for the primary outcome measure, comparing only children in each group who did not receive antibiotics in the first 6 months of the post-trial follow-up period, showed a risk difference of 32% (95% confidence intervals 13% to 51%).A sensitivity analysis, comparing those who were treated with antibiotics after the six months with those who did not receive any antibiotics after the six months follow-up period, could also have been performed. A Cochrane review on antibiotic treatment of children with AOM3 did not find any differences in AOM recurrence in children treated with antibiotics versus placebo (risk ratio 0.93 95% confidence intervals 0.78-1.10). The included trials in the review all had shorter follow-up periods – up to one year. An update of this Cochrane review should preferably include this present study by Bezáková et al as a long term outcome of antibiotic treatment. As the authors state, the use of antibiotics early in an episode of AOM may impair the natural immune response and weaken the protection against further episodes or may cause an unfavourable shift towards colonisation with resistant pathogens, which are likely to promote recurrence of infection. However, for the first six months of follow-up, recurrence rates in the amoxicillin and placebo group were similar (51% vs 50%, risk difference 1%, 95% confidence intervals -12% to 15%).We find it hard to believe that previous antibiotic treatment of AOM causes late recurrences of AOM – but not early recurrences. It is worthwhile conducting a similar study of both the long (up to one year) and very long (several years) term effects, as more information is needed both of the possible long term benefits and harms of antibiotic treatment of children with AOM. For more information see CREBP Journal Club

On 2014 Dec 18, CREBP Journal Club commented:

Interestingly, recurrent acute otitis media (AOM) occurred more often in children originally treated with amoxicillin. However, the corresponding confidence intervals are wide and the results should be interpreted with caution. It is necessary to conduct similar long term follow-up studies to gain more knowledge about the long term effect and possible harms of antibiotic treatment. The authors identified possible confounders such as sex, allergy, and history of recurrent AOM. It might have been relevant to ask the parents “Has your child had antibiotics since after the trial”, and taken this possible confounder into account as well. The article does not give any information on subsequent antibiotic use after the first six months of the post-trial follow-up period. Sensitivity analysis for the primary outcome measure, comparing only children in each group who did not receive antibiotics in the first 6 months of the post-trial follow-up period, showed a risk difference of 32% (95% confidence intervals 13% to 51%).A sensitivity analysis, comparing those who were treated with antibiotics after the six months with those who did not receive any antibiotics after the six months follow-up period, could also have been performed. A Cochrane review on antibiotic treatment of children with AOM3 did not find any differences in AOM recurrence in children treated with antibiotics versus placebo (risk ratio 0.93 95% confidence intervals 0.78-1.10). The included trials in the review all had shorter follow-up periods – up to one year. An update of this Cochrane review should preferably include this present study by Bezáková et al as a long term outcome of antibiotic treatment. As the authors state, the use of antibiotics early in an episode of AOM may impair the natural immune response and weaken the protection against further episodes or may cause an unfavourable shift towards colonisation with resistant pathogens, which are likely to promote recurrence of infection. However, for the first six months of follow-up, recurrence rates in the amoxicillin and placebo group were similar (51% vs 50%, risk difference 1%, 95% confidence intervals -12% to 15%).We find it hard to believe that previous antibiotic treatment of AOM causes late recurrences of AOM – but not early recurrences. It is worthwhile conducting a similar study of both the long (up to one year) and very long (several years) term effects, as more information is needed both of the possible long term benefits and harms of antibiotic treatment of children with AOM. For more information see CREBP Journal Club