Reference: Cochrane Database Syst Rev. 2019 Jun 18;6(6):CD012941 Level 2 [mid-level] evidence
Acute otitis media (AOM), infection of the middle ear, is a cause of fever, irritability, and earache in children. Otitis Media remains the most common cause of antibiotic therapy in children (JAMA. 2009 Aug 19). Increasing use of antibiotics also leads to increased likelihood of antibiotic resistance (Ann Intern Med. 2003). Some children are so prone to AOM that they require surgery for placement of tympanostomy tubes, which is the most common surgery performed on children in the United States (Otolaryngol Head Neck Surg. 2013). In 2010 in the United States, 13.6 million pediatric Otitis Media diagnoses were made in the ambulatory setting and 413,000 myringotomy with tympanostomy tube procedures were performed in the ambulatory setting (Laryngoscope. 2018). Probiotics are already being utilized in hospitals in combination with antibiotics to help prevent infections such as Clostridium Difficile Colitis (Ann Intern Med. 2012). In the systematic review to be discussed, the authors attempt to assess efficacy in using probiotics for the prevention or treatment of AOM.
A recent Cochrane review of 17 randomized trials with 3,488 children (mean age 2.4 years old) evaluated the use of probiotics for the prevention of AOM (Cochrane Database Syst Rev. 2019 Jun 18). In all of the trials, probiotics were compared to either placebo, usual care, or no probiotic (control). Clinical heterogeneity among trials included variability in type of probiotic used (11 trials evaluated Lactobacillus-containing probiotics and 6 trials evaluated Streptococcus-containing probiotics), duration of use (range 20 days to 2 years), and age at administration (mean age range 1 month to 17.5 years). Most of the trials (12) included children not prone to AOM. 16 trials were included in the meta-analysis.
Compared to control, use of probiotics was associated with reduced AOM in children in the overall analysis of 16 trials with 2,691 children (risk ratio [RR] 0.77, 95% CI 0.63-0.93, number needed to treat [NNT] 7-37 with AOM in 39% of control group), reduced AOM in children not prone to AOM in analysis of 11 trials with 2,227 children (RR 0.64, 95% CI 0.49-0.84, NNT 7-22 with AOM in 29% of control group), reduced risk of any other infection in analysis of 11 trials with 3,610 children (RR 0.75, 95% CI 0.65-0.87, NNT 8-22 with other infections in 36% of control group), and reduced use of antibiotics for any infection in analysis of 8 trials with 1,768 children (RR 0.66, 95% CI 0.51-0.86, NNT 6-18 with antibiotic use in 40% of control group). All results were limited by significant heterogeneity. There were no significant differences in AOM in children prone to AOM in analysis of 5 trials with 734 children, adverse events. or school days lost in analysis of 4-5 trials (results limited by significant heterogeneity).
Overall, probiotics appear to have a beneficial impact on the incidence of AOM without adverse outcomes. The meta-analysis assessed a large number of trials and children, 16 and 2,691 respectively, with a wide variety of ages included in these studies. The NNT for reducing risk of any infection (NNT 8-22) and reducing use of antibiotics for any infection (NNT 6-18) was also promising and may indicate applicability of probiotics for prophylaxis against multiple infections in the future.
However, there were multiple limitations of the meta-analysis as type of probiotic used varied, with additional differences in duration of administration. Probiotics have already been suggested to be helpful in a variety of infections, especially those related to the colon, with rare adverse effects (Ann Intern Med 2012). While various studies have assessed multiple different probiotic strains, this meta-analysis was the first to compare these strains and durations in the setting of AOM. Further studies will need to be performed to evaluate the true impact of each specific probiotic and those infections that may be affected by them. Additionally, studies will need to assess appropriate duration of probiotic therapy. Perhaps we can someday decrease the proportion of children acquiring AOM and thus decrease the need for antibiotic treatment or surgical intervention.
For more information, see the topic Acute Otitis Media (AOM) in Children in DynaMed.
Sophia Elias is a second-year resident at the Memorial Health University Medical Center Family Medicine Residency. She has remained in Georgia for the entirety of her training, beginning with the University of Georgia for her undergraduate degree and Mercer University in Savannah for her medical degree. She has enjoyed living in Savannah for the last several years and especially enjoys living on the coast. She plans to stay in Savannah after she finishes her training.
Faculty contributions by Dr. Marvin Sineath