A double-blind comparative clinical trial of cephalexin and ampicillin in the treatment of childhood acute otitis media

Acute Otitis Media

A typical case of acute otitis media in a pediatric patient is presented. The pathophysiology of the disorder, as well as its incidence, etiology, complications, and sequelae are discussed. Past treatment methods and current therapeutic recommendations pertaining to antibiotics and other adjuncts are included.

Comparison of study designs for acute otitis media trials

BACKGROUND

A framework for evaluating the efficacy of antibiotics in development as well as those currently approved for acute otitis media (AOM) is needed.

OBJECTIVE

Review strengths and limitations of various antibiotic trial designs and their outcome measures.

METHODS

A review of 157 published trials involving 36,710 subjects for the treatment of AOM.

RESULTS

AOM trials have three designs: (1) clinical, clinical diagnosis and assessment of outcomes; (2) single tympanocentesis, microbiologic diagnosis (by middle ear fluid culture) and clinical assessment of outcomes; and (3) double tympanocentesis, microbiologic diagnosis and microbiologic outcome assessment. Identifiable strengths and limitations of each design are reviewed. Case definitions for entry of children in trials of AOM vary widely. The lack of stringent diagnostic criteria in a clinical design allows for inclusion of a significant proportion of children with a non-bacterial etiology (i.e., viral AOM or otitis media with effusion). Tympanocentesis increases diagnostic accuracy at study entry; however, the procedure is confounding because of its potentially therapeutic benefit and the procedure is not performed in a uniform manner. A second tympanocentesis allows a high sensitivity to detect microbiologic eradication, but it does not correlate with clinical outcomes in half of the cases. The timing of outcome assessment also varies widely among trials.

CONCLUSIONS

Improved clinical diagnosis criteria for AOM are needed to enhance specificity; emphasis on a bulging tympanic membrane has the best evidence base. Tympanocentesis within study designs has merits. At study entry it assures diagnostic accuracy but may alter outcomes and it is useful to document microbiologic outcomes but lacks specificity for clinical outcomes. For all designs, test of cure assessment 2-7 days after completion of therapy seems most appropriate.

Evidence assessment of management of acute otitis media: I. The role of antibiotics in treatment of uncomplicated acute otitis media

CONTEXT

In 1995, >5 million episodes of acute otitis media (AOM) accounted for $3 billion in health care expenditures.

OBJECTIVES

To synthesize the literature on the natural history of AOM, the effectiveness of antibiotic treatment in uncomplicated AOM, and the relative effectiveness of specific antibiotic regimens.

DATA SOURCES

Seven electronic databases for articles published between 1966 and March 1999 and reference lists in proceedings, published articles, reports, and guidelines.

STUDY SELECTION

Two physicians independently assessed each article. Studies addressing AOM in children 4 weeks to 18 years old were included; those addressing children with immunodeficiencies or craniofacial abnormalities were excluded. Randomized, controlled trials (RCTs) were used to assess antibiotic effectiveness, and RCTs and cohort studies were used to assess the natural history of AOM. Among the 3491 citations identified, 80 (2.3%) met our inclusion criteria.

DATA EXTRACTION

Two physicians independently abstracted data and assessed the quality of studies using a validated scale for RCTs and 8 quality components for cohort studies.

DATA SYNTHESIS

Random-effects estimates of pooled absolute rate differences of outcomes were derived, and heterogeneity of both the rates and rate differences was assessed. Children with AOM not treated with antibiotics experienced a 1- to 7-day clinical failure rate of 19% (95% confidence interval: 0.10-0.28) and few suppurative complications. When patients were treated with amoxicillin, the 2- to 7-day clinical failure rate was reduced to 7%, a 12% (95% confidence interval: 0.04-0.20) reduction. Adverse effects, primarily gastrointestinal, were more common among children on cefixime than among those on ampicillin or amoxicillin. They were also more common among children on amoxicillin-clavulanate than among those on azithromycin.

CONCLUSIONS

The majority of uncomplicated cases of AOM resolve spontaneously without apparent suppurative complications. Ampicillin or amoxicillin confers a limited therapeutic benefit. There is no evidence to support any particular antibiotic regimens as more effective at relieving symptoms. Certain antibiotics are more likely than others to cause diarrhea and other adverse events.

A review of clinical trials regarding treatment of acute otitis media

A survey was made of the English language literature on clinical trials of therapy in acute otitis media. The articles were analysed systematically for 24 parameters related to study design. We retrieved 50 studies published between 1965 and 1989. Surprisingly, the combination of a double-blind method, clearly defined inclusion criteria, and criteria for outcome was found in only 13 studies. Most of these 13 compared different antibiotic regimens and only 4 were placebo-controlled. A recommendation based on the conclusions reached can, even in these 13 studies, hardly be obtained due to failure to show an overall difference in favour of a specific treatment regimen. Our study shows that many trials are methodologically flawed which makes it difficult to accept their results. In view of current controversy on management of acute otitis media, well conducted placebo-controlled clinical trials are still needed.

Treatment of respiratory tract infections with cephalosporin antibiotics

Infections of the respiratory tract are among the most common causes for antibiotic prescribing. Their diagnosis within the community is generally limited to clinical criteria, and microbiological information is frequently lacking. Hospitalised patients with respiratory tract infections are more likely to undergo diagnostic sampling, but difficulties remain in reliably defining a microbial aetiology, thereby providing a confident basis for antibiotic selection. In considering the role of the cephalosporins in the treatment of respiratory tract infections, over 500 published articles have been reviewed. The pharmacokinetic considerations are discussed and the limitations of existing methodology are emphasised. Individual agents are reviewed by site of sepsis and conclusions are drawn from both comparative and non-comparative studies and in relation to currently recommended regimens. Although oral cephalosporins are widely used to treat upper respiratory tract infections, none is considered ideal, especially where Haemophilus influenzae is pathogenic. In the case of lower respiratory tract infections the beta-lactamase stable parenteral cephalosporins have become widely used to treat pneumonia in hospitalised patients, especially where Gram-negative enteric bacilli are of aetiological importance. However, the lack of activity of these drugs against Legionella spp., Mycoplasma pneumoniae and Coxiella burnetii must be emphasised. Another area of increasing use is in the treatment of infective exacerbations in patients suffering from cystic fibrosis of the lungs where Pseudomonas aeruginosa is pathogenic; ceftazidime in particular has proved a useful alternative to earlier antipseudomonal penicillin antibiotics.