Bacterial biofilm in adenoids of children with chronic otitis media. Part I: a case control study of prevalence of biofilms in adenoids, risk factors and middle ear biofilms

Abstract

Background: Biofilms are communities of bacteria embedded in a self-produced glycocalyx matrix. Adenoids have been shown to harbor bacterial biofilms.

Aim/objectives: To compare the prevalence of biofilms in adenoid of children with chronic otitis media (COM) (group1) versus a control group without any COM (group 2) having adenoids removed because of hypertrophy.

Material and methods: One hundred and three children were prospectively enrolled in this case-control study, group 1 (n = 52) and group 2 (n = 51). The main outcome measurement was the prevalence of biofilm in adenoidectomy specimens analyzed using confocal laser scanning microscopy. Children in group 1 who had middle ear (ME) effusion and requiring the insertion of a tympanostomy tube underwent biopsy of the ME mucosa and effusion sampling.

Results: Biofilms were found in adenoids’ specimens of both groups and in the ME biopsy and effusion. The biofilm prevalence in adenoids was 63.5% (33/52) in group 1 and 47.1% (24/51) in group 2. Day nursery and previous antibiotics intake were significantly more frequent in group 1 than in group 2.

Conclusions and significance: This case-control study demonstrates that adenoid tissue in children with COM contains more mucosal biofilms than adenoid tissue removed for hypertrophy. Biofilm was seen in ME biopsies and effusion.

Chinese abstract

背景：生物膜是自产糖萼基质中的细菌群落。腺样体显示含有细菌生物膜。

目的：与因肥大而切除腺样体的对照组（第2组）进行比较, 研究慢性中耳炎（COM）（第1组）儿童腺样体中生物膜的发生率, 。

材料和方法：本病例对照研究前瞻性地招募了103名儿童, 分为第一组（n = 52）和第二组（n = 51）。主要观察指标是用共聚焦激光扫描显微镜分析腺样体切除术标本中生物膜的发生率。第1组中, 有中耳积液需要插入鼓室导管的儿童接受了鼓室粘膜活检和积液取样。

结果：两组的腺样体标本及ME活检和积液中均发现生物膜。第一组中腺样体生物膜的发生率为63.5%（33/52）, 第二组为47.1%（24/51）。日间托儿和以前的抗生素摄入量在第一组中明显高于第2组。

结论与意义：本项病例对照研究表明, COM患儿的腺样体组织中含有的粘膜生物膜多于因肥大而切除的腺样体组织。在ME活检和积液中发现生物膜。

Keywords:

• Biofilms
• adenoids
• otitis media
• microbiota

Acknowledgment

The authors would like to thank Prof. Jan J Gröte, for his counseling in this study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was funded by APHP, Clinical Research Unit.