Diagnosing and managing common food allergies: a systematic review.
BACKGROUND
There is heightened interest in food allergies but no clear consensus exists regarding the prevalence or most effective diagnostic and management approaches to food allergies.


OBJECTIVE
To perform a systematic review of the available evidence on the prevalence, diagnosis, management, and prevention of food allergies.


METHODS
Electronic searches of PubMed, Cochrane Database of Systematic Reviews, Cochrane Database of Abstracts of Reviews of Effects, and Cochrane Central Register of Controlled Trials. Searches were limited to English-language articles indexed between January 1988 and September 2009.


METHODS
Diagnostic tests were included if they had a prospective, defined study population, used food challenge as a criterion standard, and reported sufficient data to calculate sensitivity and specificity. Systematic reviews and randomized controlled trials (RCTs) for management and prevention outcomes were also used. For foods where anaphylaxis is common, cohort studies with a sample size of more than 100 participants were included.


METHODS
Two investigators independently reviewed all titles and abstracts to identify potentially relevant articles and resolved discrepancies by repeated review and discussion. Quality of systematic reviews and meta-analyses was assessed using the AMSTAR criteria, the quality of diagnostic studies using the QUADAS criteria most relevant to food allergy, and the quality of RCTs using the Jadad criteria.


RESULTS
A total of 12,378 citations were identified and 72 citations were included. Food allergy affects more than 1% to 2% but less than 10% of the population. It is unclear if the prevalence of food allergies is increasing. Summary receiver operating characteristic curves comparing skin prick tests (area under the curve [AUC], 0.87; 95% confidence interval [CI], 0.81-0.93) and serum food-specific IgE (AUC, 0.84; 95% CI, 0.78-0.91) to food challenge showed no statistical superiority for either test. Elimination diets are the mainstay of therapy but have been rarely studied. Immunotherapy is promising but data are insufficient to recommend use. In high-risk infants, hydrolyzed formulas may prevent cow's milk allergy but standardized definitions of high risk and hydrolyzed formula do not exist.


CONCLUSIONS
The evidence for the prevalence and management of food allergy is greatly limited by a lack of uniformity for criteria for making a diagnosis.
Chafen
Jennifer J Schneider
JJ
VA Palo Alto Healthcare System, Palo Alto, California, USA. jjschnei@stanford.edu
Newberry
Sydne J
SJ
Riedl
Marc A
MA
Bravata
Dena M
DM
Maglione
Margaret
M
Suttorp
Marika J
MJ
Sundaram
Vandana
V
Paige
Neil M
NM
Towfigh
Ali
A
Hulley
Benjamin J
BJ
Shekelle
Paul G
PG
D002648:Child; D004035:Diet Therapy / Q000379:methods; D005512:Food Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control / Q000628:therapy; D006801:Humans; D007167:Immunotherapy; D007223:Infant; D041943:Infant Formula; D015995:Prevalence