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Letter
Dr. Donald Low reported that the use of high-dose amoxicillin is
recommended for the treatment of otitis media;1 however, an overview of randomised controlled trials of antimicrobials
for otitis media has found little evidence that these drugs decrease the duration and severity of symptoms.2 Furthermore,
it suggested that restricting the routine use of antibiotics as first line treatment for otitis media may reduce
the prevalence of resistant pneumococci. In the Netherlands, where the first line treatment is simply symptomatic,
the prevalence of pneumococcal resistance is much lower than in other countries. In Iceland, prevalence of resistant
pneumococci declined after a campaign to decrease antibiotic use, especially for otitis media.
Changes in prescription policy for otitis media may substantially
reduce the quantity of amoxicillin prescribed.3 In order to preserve antibiotics for those patients who really
need them, it may be a wiser policy to avoid their use as the first-line therapy for otitis media, rather than
to increase the dose.
References
- Low DE. 1999. APUA Newsletter 17(1):5.
- Froom J, Culpepper L, Jacobs M et al. 1997. Br Med
J 315: 98-102.
- Cates C. 1999. Br Med J 318: 715-716.
Merlin Willcox, MD
Doctors’ Residence
Birmingham Heartlands Hospital
Birmingham, England, UK
Author's Reply
Dr. Wilcox raises two important issues: the questionable value of
antibiotics for the treatment of acute otitis media (AOM) and the appropriate dosage of amoxicillin. Currently
antimicrobial treatment of AOM accounts for a large proportion of all antimicrobials used (i.e., >90% of all
antimicrobial use during the first 2 years of life), yet there is probably no other syndrome that has generated
so much controversy regarding the value of antibiotic treatment.1 Arguments for the early institution of antimicrobial
treatment include reducing the duration of clinical symptoms and preventing suppurative complications.2 Yet, the
benefits of antibiotic treatment on short-term and long-term outcomes remain unproven. In addition, the majority
of children will have spontaneous resolution of infection, but there are currently no clinical or laboratory measures
to accurately predict which children will spontaneously improve.
However, most would agree that some patients with AOM due to bacteria
will benefit from effective antibiotic therapy. Dagan et al. used tympanocentesis to culture middle ear fluid (MEF)
before and after initiation of treatment.3 They found that clinical failures were associated with inability to
eradicate the causative organism of AOM from the MEF within 3 to 4 days after initiation of antibiotic treatment.
The Centers for Disease Control and Prevention and the American Academy of Pediatrics have sponsored recommendations
for the judicious use of antibiotics. They recommend that attempts be made to increase otoscopic skills so as to
be able to differentiate otitis media with effusion (OME), for which antibiotics are not recommended, from AOM.4
Doing this could reduce inappropriate prescriptions use by 30%. In the Netherlands the Dutch College of Family
Doctors has recommended treating patients symptomatically for three days in those >2 years of age and up to
two days for those between the ages of six months and two years before antibiotic treatment is considered. Unfortunately,
this approach may not be feasible or cost-effective in many countries because of how healthcare is delivered.
If we believe that there is a subset of patients that benefit from
antimicrobial therapy, then it behooves us to use the most effective agent. The most common bacterial pathogens
in AOM are Streptococcus pneumoniae
(30 to 35%), Haemophilus influenzae
(20 to 25%) and Moraxella catarrhalis
(10 to 15%). Of these S. pneumoniae
is clearly the most important. Howie et al. provided clinical details in 858 episodes of AOM in relation to the
initial bacteriologic findings.5 They found that episodes due to S. pneumoniae were significantly more often associated
with severe pain and with high fever than were the cases attributable to H.
influenzae. When a second tap was done in those not treated
with an antimicrobial, 84% of the S. pneumoniae persisted, as compared to 52% of the H.
influenzae.
There is general agreement that the drug of choice for the treatment
of AOM is amoxicillin. However, as the prevalence and degree of resistance increase, what is the optimal dose?
Gehanno et al. found in a study of AOM clinical failures carried out in Paris during 1996 that penicillin-resistant
pneumococci were the most common bacterial isolates from the MEF.6 This has been the rationale for the increased
dosage of amoxicillin for the treatment of AOM in areas where penicillin-resistant pneumococci are endemic.4
The benefits of antibiotics for AOM are modest but consistently
measurable. Making the correct diagnosis by excluding OME can dramatically reduce inappropriate antibiotic use.
References
- Del Mar C, Glasziou P, Hayem M. 1997. BMJ 314: 1526-1529;
van Buchem FL, Peeters MF, van ‘t Hof MA. 1985. BMJ (Clin Res Ed) 290: 1033-1037; Froom J, Culpepper L, Jacobs
M, et al (comments). 1997. BMJ 315: 98-102.
- Berman S. 1995. N Engl J Med 332: 1560-1565.
- Dagan R, Leibovitz E, Greenberg D, Yagupsky P, Fliss
DM, Leiberman A. 1998. Pediatr Infect Dis J 17: 776-782.
- Dowell SF, Butler JC, Giebink GS, et al. 1999. Pediatr
Infect Dis J 18: 1-9.
- Howie VM, Ploussard JH, Lester RLJ. 1970. Pediatrics
45: 29-35.
- Gehanno P, N’Guyen L, Derriennic M, Pichon F, Goehrs
JM, Berche P. 1998. Pediatr Infect Dis J 17: 885-890.
Donald E. Low, MD
Dept of Microbiology
Mount Sinai Hospital
Toronto, Ontario, Canada
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