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Three Part Question

Do [children with OME] have an [increased risk of allergic rhinitis] than [children without OME] ?

Clinical Scenario

Spiro, a 12-year-old boy, was referred to the Allergy Clinic of Department of Pediatrics because of Otitis Media with Effusion (OME) that had been present for the last four years. A pediatrician and an otolaryngologist advised a consultation with an allergist because they believed that Spiro had OME because he suffered from allergic rhinitis (AR). Should we look for AR in every child with OME?

Search Strategy

Cochrane Database of Systematic Reviews and Medline using the Pubmed interface. 1966-Aug 2003.
Cochrane: "otitis media AND allergy"
PubMed: "otitis media with effusion AND allergic rhinitis"

Search Outcome

Cochrane - 13 references - none relevant. Medline 62 references - 4 relevant

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Caffarelli et al, 1998, Italy	172 children with OME referred because of symptoms to the Centre for the Study of OME 200 healthy children as controls	Case-control study (level 2b)	Prevalence of allergic rhinitis	16.3% in children with OME, 5.5% in controls. OR = 3.34(95% CI 1.6 to 6.3) p<0.001	Well-defined and rigorous diagnostic criteria of OME and AR Presence of an adequate random control population Sufficient sample size
Kayhan et al, 2002, Turkey (abstract only)	22 children with OME. 21 children with no symptoms of otolaryngological disease as controls	Case-control study (level 2b)	Prevalence of allergic rhinitis	23% in children with OME.4.8% in controls OR = 5.9 (95%CI 0.6 to 55.4)p>0.05	Good quality of definition of diagnosis of OME and AR Small numbers Article in turkish
Alles et al, 2001, UK	209 children with OME	Case series (level 4)	Prevalence of atopy and allergic disease (rhinitis, asthma, eczema)	Prevalence of AR=89%	Poor quality of definition of diagnosis of OME and AR Lack of a control population
Ogawa, 2002, Japan (abstract only)	185 children with OME	Case series (level 4)	Description of various outcomes (allergic and non-allergic)	Prevalence of AR = 14%	Unknown quality of definition of diagnosis of OME and AR Lack of a control population Article in Japanese

Comment(s)

The full text of two relevant studies (Ogawa and Kayhan et al) was not accessible to us (one published in Japenese, the other in Turkish); however, the abstract furnished sufficient details for a summary evaluation of their validity and utility for our question. The studies that we examined in full text (Caffarelli et al, 1998; Alles et al, 2001) showed marked difference in the prevalence of AR in children with OME: 16.3% vs 89%. Trying to explain this discrepancy, it can be noted that the study of Alles et al (2001) is affected by some methodological imperfections that seriously compromise its validity. It lacks a well-defined control group and the study definition of AR and OME are weak. For AR, neither the appearance of the symptoms after exposure to an allergen nor the demonstration, necessarily, of sensitisation to an allergen through measurement of the specific IgE is required. Even the definition of OME was not strong: an unconfirmed history of OME was sufficient for enrolment. The prevalence of the AR in children with OME in the study of Caffarelli et al (1998) gives the more reliable estimates; because of their study is prospective, and the authors have adopted rigorous diagnostic criteria for both the illness studied (AR and OME), have included an adequate control population and have enrolled a sufficient number of children. The prospective design of the study reduces the recall bias and the possibility of differences in the management of the patients. A rigorous definition of allergic rhinitis allows avoiding its overdiagnosis and the inclusion of patients with non-allergic rhinitis. OME was defined prospectively with tympanometry performed on all the patients (to define cases and controls). The presence of a control group allows us to quantify the parameter we consider the most interesting, i.e. the difference (Absolute Risk Increase) in the prevalence of the allergic rhinitis between the children with OME and the ones without. And finally, the presence of a large sample makes the estimate of the Absolute Risk Increase more accurate, tightening its Confidence Interval. The duration of OME is an important variable in management decisions: studies of children in day care note that many will have brief periods of time (one or several days) with OME that spontaneously clears; in contrast other children will have OME for months. Only for the latter children would any intervention have the potential to be useful. However, the studies on the efficacy of the anti-allergic therapy in the treatment of children with OME are few, methodologically weak and inconclusive. JM Bernstein (1)wrote in 1996: "Irrespective of the theoretical mechanism, the relationship between allergy and otitis media with effusion will remain controversial until well-controlled clinical studies are conducted documenting that in select populations antiallergy therapy is efficacious in preventing or limiting the duration of otitis media with effusion". Today, the situation is unchanged.

Clinical Bottom Line

The prevalence of allergic rhinitis is significantly higher in children with otitis media with effusion (16.3%) than in healthy controls (5.5%). Allergologic screening is not necessary in children with OME as all children with allergic rhinitis present all or some of the characteristic symptoms. Treatment for allergic rhinitis has not been shown to improve otitis media with effusion. If there are signs or symptoms of allergic rhinitis, further evaluation is justified, because of the potential benefit of treatment for the rhinitis.

References

1. Caffarelli C, Savini E, Giordano S, et al. Atopy in children with otitis media with effusion. Clin Exp Allergy 1998;28(5):591-6.
2. Kayhan FT, Ergez E, Hatipoglu A, et al. The incidence of allergic rhinitis in children with otitis media with effusion. Kulak Burun Bogaz Ihtis Derg 2002;9(3):184-7.
3. Alles R, Parikh A, Hawk L, et al. The prevalence of atopic disorders in children with chronic otitis media with effusion. Pediatr Allergy Immunol 2001;12(12):102-6.
4. Ogawa H. Otitis media with effusion: a study of 346 cases in an outpatient clinic. Nippon Jibiinkoka Gakkai Kaiho 2002;105(8):863-72.
5. Bernstein JM. Role of allergy in eustachian tube blockage and otitis media with effusion: a review. Otolaryngol Head Neck Surg 1996;114(4):562-8.