Recurrent acute otitis media--prophylactic penicillin treatment: a prospective study. Part I

Natural history of untreated otitis media

OBJECTIVE/HYPOTHESIS

Data from cohort studies and untreated groups in randomized controlled trials can be identified through systematic literature review and synthesized with meta-analysis to estimate natural history of acute otitis media (AOM) and otitis media with effusion (OME).

STUDY DESIGN

Systematic literature review and meta-analysis.

METHOD

Source articles were identified by MEDLINE search through August 2002 plus manual crosschecks of bibliographies and published meta-analyses. Data were abstracted independently by two investigators and combined with random effects meta-analysis to estimate spontaneous resolution, 95% confidence intervals (CI), and heterogeneity. Sensitivity analysis was performed.

RESULTS

Sixty-three articles met inclusion criteria. AOM symptoms improved within 24 hours without antibiotics in 61% of children (95% CI, 50-72%), rising to 80% by 2 to 3 days (95% CI, 69-90%). Suppurative complications were comparable if antibiotics were withheld (0.12%) or provided (0.24%). Children entered recurrent AOM trials with a mean rate of 5.5 or more annual episodes but averaged only 2.8 annual episodes while on placebo (95% CI, 2.2-3.4). No AOM episodes occurred in 41%, and only 17% remained otitis prone (3 or more episodes). OME after untreated AOM had 59% resolution by 1 month (95% CI, 50-68%) and 74% resolution by 3 months (95% CI, 68-80%). OME of unknown duration had 28% spontaneous resolution by 3 months (95%, CI 14-41%), rising to 42% by 6 months (95% CI, 35-49%). In contrast, chronic OME had only 26% resolution by 6 months and 33% resolution by 1 year.

CONCLUSIONS

The natural history of otitis media is very favorable. Combined estimates of spontaneous resolution provide a benchmark against which to judge new or established interventions. The need for surgery in children with recurrent AOM or chronic OME should be balanced against the likelihood of timely spontaneous resolution and the potential risk of learning, language, or other adverse sequelae from persistent middle ear effusion. Further research is needed to identify prognostic factors that can target children unlikely to improve spontaneously for earlier intervention.

Antibiotics for the prevention of acute and chronic suppurative otitis media in children

BACKGROUND

Acute otitis media (AOM) is a common childhood illness. These middle ear infections may be frequent and painful. AOM may be associated with perforation of the tympanic membrane and can progress to chronic suppurative otitis media (CSOM).

OBJECTIVES

To determine the effectiveness of long-term antibiotics (for longer than six weeks) in preventing any AOM, AOM with perforation and CSOM.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (January 1966 to March Week 3 2006), OLD MEDLINE (1950 to 1965), EMBASE (1990 to December 2005) and the references of relevant studies.

SELECTION CRITERIA

All randomised controlled trials of long-term (longer than six weeks) antibiotics versus placebo or no treatment for the prevention of AOM, AOM with perforation, or CSOM were eligible.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data for: any AOM; episodes of AOM; any recurrent AOM; episodes of illness; any side effects; any antibiotic resistance, as well as outcomes at end of intervention (any AOM); and following cessation of intervention (any AOM). For dichotomous outcomes, the summary risk ratio (fixed and random-effects models) was calculated. For rate outcomes, the summary incidence rate ratio was calculated.

MAIN RESULTS

Sixteen studies involving 1483 children met our inclusion criteria. All studies enrolled children at increased risk of AOM, and in seven studies the children were prone to otitis media. The majority of studies were high quality and most (15 studies) reported data for our primary outcomes. None reported AOM with perforation or CSOM. Long-term antibiotics reduced any episode of AOM (13 studies, 1358 children, risk ratio (RR) 0.62, 95% CI 0.52 to 0.75; random-effects model) and number of episodes of AOM (12 studies, 1112 children, incidence rate ratio (IRR) 0.48, 95% CI 0.37 to 0.62; random-effects model). Approximately five children would need to be treated long term to prevent one child experiencing AOM whilst on treatment. Antibiotics prevented 1.5 episodes of AOM for every 12 months of treatment per child. Statistical heterogeneity was explored. Long-term antibiotics were not associated with a significant increase in adverse events (11 studies, 714 children, RR 1.99, 95% CI 0.25 to 15.89; random-effects model).

AUTHORS' CONCLUSIONS

For children at risk, antibiotics given once or twice daily will reduce the probability of AOM while the child is on treatment. Antibiotics will reduce the number of episodes of AOM per year from around three to around 1.5. We believe that larger absolute benefits are likely in high-risk children. These conclusions were not affected by sensitivity analyses.

Short-term penicillin-V prophylaxis did not prevent acute otitis media in infants

OBJECTIVE

To determine whether prophylactic, short-term penicillin V treatment during upper respiratory tract infections can prevent the occurrence of recurrent acute otitis media in young children.

METHODS

Seventy children were studied in a prospective, double-blind, placebo-controlled study. All children had suffered their first episode of acute otitis media before the age of 6 months. After inclusion in the study group, administration of penicillin V or placebo was initiated by the parents at subsequent upper respiratory tract infections. The children were examined by otomicroscopy within 3 days after treatment was initiated. The children were scheduled for a total follow-up period of 12 months, including bimonthly visits for check-up irrespective of treatment periods.

RESULTS

There were 304 treated episodes of upper respiratory tract infection. There was no significant difference in the number of acute otitis episodes between groups.

CONCLUSION

Initiation of penicillin V prophylaxis at upper respiratory tract infection in small children did not prevent recurrent acute otitis media in this study.

Clinical aspects on antibiotic resistance: upper respiratory tract infections

In view of the increased resistance to antibiotics in several upper airway pathogens, the clinical rationale for use of antimicrobial therapy in various upper respiratory tract infections is discussed. The diagnostic skill and the clinical significance of various bacteria are taken into account and strategies for treatment of the different infections, with focus on acute otitis media, are discussed.

Prevention of recurrent acute otitis media in otitis-prone children by intermittent prophylaxis with penicillin

The question whether penicillin V (pcV) given intermittently upon signs of upper respiratory tract infections (URTI) in otitis-prone children might prevent recurrent bouts of acute purulent otitis media (AOM) is addressed. As compared with continuous long-term antibiotic treatment as prophylaxis in otitis-prone children, intermittent administration would reduce the overall consumption of antibiotics. Seventy-six otitis-prone children less than 18 months of age were included in this double-blind, randomized, placebo-controlled multicentre study. Follow-up was from January till June. One hundred and twenty-three episodes of AOM occurred. The number of AOM episodes was reduced by 50% in the children on pcV during URTI episodes as compared with those on placebo. No obvious ecological drawbacks were noted. Thus, the described mode of pcV administration seems to be a rational and safe way to reduce the number of AOM episodes in otitis-prone children.

Penetration of penicillin V to tonsillar surface fluid in healthy individuals and in patients with acute tonsillitis

In the treatment of group A streptococcal tonsillitis, as the bacteria are located on the epithelial surface, an important determinant of outcome is the concentration of penicillin in extracellular tonsillar surface fluid. Accordingly, we investigated the concentration of penicillin in serum, and penetration to tonsillar surface fluid and saliva in nine patients with acute group A streptococcal tonsillitis and in nine healthy controls. Among the healthy subjects, despite high serum penicillin concentrations (mean, 2.04 micrograms/ml), there was no penetration to tonsillar surface fluid or to saliva, whereas erythromycin penetrated to tonsillar surface fluid in 3/6 cases. Of the nine patients with acute tonsillitis, on the first day of treatment eight manifested high concentrations of penicillin in tonsillar surface fluid (mean, 0.34 micrograms/ml--i.e. well above the minimal inhibitory concentration (MIC) for group A streptococci), but penetration to saliva was found in only two patients. On the tenth day of treatment, penicillin was not present in the saliva of any of the patients and was present in the tonsillar surface fluid of only one. The results suggest that measurable concentrations of penicillin in tonsillar surface fluid can only be obtained in the presence of inflammation with fluid exudation through the tonsillar epithelium.

Antimicrobial prophylaxis for recurrent acute otitis media

Antimicrobial prophylaxis for recurrent otitis media was first reported in 1960 in an uncontrolled study using a long-acting sulfonamide in Native American children younger than 11 years of age. In subsequent controlled studies using various antimicrobial drugs (primarily aminopenicillins or sulfonamides) subjects receiving prophylaxis continued to have episodes of acute otitis media, but at rates substantially lower than those of controls. More recently, prophylaxis has appeared effective in reducing the number of acute recurrences, but not the cumulative proportion of time with middle ear effusion that was present independent of such recurrences. Although questions remain about choice of drug, optimal dosage schedules, risk of untoward drug reactions, duration of use, and the risk of encouraging the emergence of resistant strains of pathogenic bacteria, antimicrobial prophylaxis currently appears to be the most logical first approach in the management of the child with recurrent otitis media.

What is an 'otitis-prone' child?

The present report concerns a random sample of 2512 children monitored for acute otitis media up to the age of two years. The criteria given by previous surveys classified from 1.8 to 41.2% of the population as 'otitis-prone', at a mean age varying between 13.4 and 18.8 months. A criterion of at least 4 episodes of acute otitis media during the next 9 months with a 30-day borderline between two distinct episodes yielded 273 children (10.8% of the population) with an acceptable mean age of 15 months. Early onset of acute otitis media was only a weak predictor of susceptibility in either the individual child or the whole population, the sensitivity levels and predictive values being too low for accurate prediction.

Treatment failure in otitis-prone children with prophylactic tympanostomy tubes is correlated with nasopharyngeal Haemophilus influenzae colonization

Tympanostomy tubes are used to prevent recurrent otitis media among otitis-prone children. However, not all children benefit from this treatment. In the present study 28 children (19 boys, 9 girls) were given bilateral tympanostomy tubes at age 9-22 months (mean 14 months). They were observed 6 months before and after tube insertion. The treatment was considered successful for 20 children. Among these, 16 completely lacked or had one episode of middle ear discharge and 4 had otorrhea on two occasions. A total of 8 children suffered from three or more episodes of otorrhea and were considered as treatment failures. In the failure group, the nasopharyngeal average carrier rate of H. influenzae 6 months before and after tube insertion was 64% vs. 29% in the group responding well to the treatment (p less than 0.001). Nonencapsulated forms of H. influenzae were in a great majority. In the failure group 7 out of 8 presented middle ear discharge as soon as within 2 weeks after tube insertion whereas this occurred in only 3 out of 20 in the responding group. IgG, IgG1 and IgG2 antibody response to pneumococcal polysaccharide (6A, 19F) were equally distributed in the two groups. The present data suggest that one reason for an unsatisfactory response to treatment with prophylactic tympanostomy tubes is nasopharyngeal colonization and subsequent middle ear infections caused by H. influenzae.

Prevention of experimental acute otitis media with penicillin V

The preventive effect of penicillin V (pcV) in pneumococcal otitis media in the rat has been studied. The pcV was administered either before bacterial challenge (prevention group) or after challenge but before the establishing of acute purulent otitis media (AOM) (early treatment group). In both cases a fulminant infection was avoided. Thus, in the prevention group no animal developed AOM and in the early treatment group the fulminant AOM was avoided in all cases. These results give further support to the idea of using long-term treatment with an antibiotic with a narrow spectrum to avoid recurrent AOM (rAOM). Furthermore the observation that early treatment might stop the development of fulminant AOM indicates another more restrictive possibility to use antibiotic as a prophylactic measure in otitis-prone children.