Presence or absence of bacteria in otitis media with effusion?

EDITORIAL

Presence or absence of bacteria in otitis media with effusion?

Luc L. M. Weckx

Professor. Chief of the Department of Otorhinolaryngology and Head and Neck Surgery - Universidade Federal de São Paulo, São Paulo, SP, Brazil

^{Correspondence}

Otitis media with effusion (OME) is an inflammation of the middle ear containing serous or mucoid secretion, an intact tympanic membrane, and no clinical signs of acute infection, which results in mild to moderate hearing loss. Consequently, a child with OME may have a poor school performance, being regarded as inattentive, in addition to asking others to repeat what they have just said and listening to television at a loud volume.

There is some controversy over whether the release of inflammatory mediators, which maintain middle ear infection, is caused by bacterial or viral antigens.¹

In the Brazilian literature, positive culture findings for middle ear effusion vary between 0 and 33%, and the most commonly detected bacteria are Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrlhalis.^2-5 When collecting material from the middle ear, it is important that contamination of the external auditory canal be ruled out.

The clinical treatment of OME is one of the most controversial and most widely discussed issues related to middle ear infections. Even though 67% of Brazilian otolaryngologists choose antibiotic therapy as first-line treatment for OME, according to a survey described by Bogar in 1998, the 1999 Brazilian Consensus on Otitis Media does not recommend the routine use of antimicrobials, reserving them for some special situations, such as recent OME cases, never-treated patients, or signs of acute infectious and/or inflammatory process.⁶

Moreover, some doubts have been raised as to the use of pneumococcal conjugate vaccine and AOM.⁷

In the study "Prevalence of bacteria in children with otitis media with effusion", written by Pereira et al.,⁸ the rate of positive culture findings was 25.1%, whereas PCR was positive in 57% of the analyzed samples. Although the use of PCR for the investigation of OME is a pioneering technique in Brazil and the results are consistent with the international literature,^9-11 the authors show that there is some discrepancy as to the positive PCR findings obtained: were viable bacteria detected or are they just fossilized remnants of bacteria (DNA fragments)?

This occurs due to the fact that in PCR the primer amplifies small bacterial DNA fragments; therefore, it is possible to have an intact fragment, but dead bacteria.

Finally, the data obtained in the referred article, showing penicillin-resistant pneumococci and Moraxella, as observed in other countries, serve as a warning to us. Also, we should recognize the restrictions imposed by the small number of isolates, as pointed out by the authors, despite the methodologically correct approach used and the careful analysis of the results.

References

1. Saffer M, Piltcher OB. Otite Média Secretora. In: Campos CAH, Costa HOO, editores. Tratado de Otorrinolaringologia. vol. 2. São Paulo: Rocca; 2002. p. 65-71.

2. Filizzola VC, Weckx LL, Carlini D, Martino MD, Mimica IM. Estudo bacteriológico da secreção da orelha média em crianças com otites média secretora crônica. Rev Bras Otorrinolaringol. 1998;64:604-8.

3. Saffer M, Lubianca Neto JF, Piltcher OB, Petrillo VF. Chronic secretory otitis media: negative bacteriology. Acta Otolaryngol. 1998;116:836-9.

4. Rezende VA, Almeida ER, Bento RF, Durigon EL, Botosso VF, Queiroz D. Estudo da flora bacteriana e viral na otite média secretora e rinofaringe na infância. Rev Bras Otorrinolaringol. 1999;65:10-7.

5. Piltcher OB. Um novo modelo experimental de OME em ratos para estudo do perfil das citocinas no continuum dessa doença [tese]. São Paulo: Faculdade de Ciências Médicas da Santa Casa de São Paulo; 2000.

6. Campos CA, JA Oliveira, Endo L, Bento R, Pignatari S, Weckx LLM. Consenso sobre Otite Média. Rev Bras Otorrinolaringol. 1999;65 Supl 8:14-17.

7. Straetemans M, Palmu A, Auranen Y, Zielhuis GA, Kilpi T. The effect of a pneumococcal conjugate vaccine on the risk of otitis media with effusion out 7 and 24 months of age. Int J Ped Otorhynolaryngol. 2003;67:1235-42.

8. Pereira MBR, Pereira MR, Cantarelli V, Costa SS. Determinação da prevalência de bactérias em crianças com otite média com efusão. J Pediatr (Rio J). 2004;80:XXXXX.

9. Hotomi M, Tabata T, Kakiuchi H, Kunimoto M. Detection of Haemophilus influenzae in middle ear of otitis media with effusion by polymerase chain reaction. Int J Ped Otol. 1993;27:119-26.

10. Post JC, Preston R, Aul J, Larkins-Pettigrew M, Rydquist-White J, Anderson K, et al. Molecular analysis of bacterial pathogens in otitis media with effusion. JAMA. 1995;273:1598-1604.

11. Hendolin P, Markkanen A, Ylikoski J, Wahlfors J. Use of multiplex PCR for simultaneous detection of four bacterial species in middle ear effusion. J Clin Microbiol. 1997;35:2854-8.

2. Filizzola VC, Weckx LL, Carlini D, Martino MD, Mimica IM. Estudo bacteriológico da secreção da orelha média em crianças com otites média secretora crônica. Rev Bras Otorrinolaringol. 1998;64:604-8.

Publication Dates

• Publication in this collection
  22 June 2004
• Date of issue
  Feb 2004