ImmunoCAP Phadiatop Infant--a new blood test for detecting IgE sensitisation in children at 2 years of age.
BACKGROUND
Correct diagnosis of immunoglobulin E (IgE)-mediated disease is the prerequisite for secondary allergy prevention during early childhood.


OBJECTIVE
To evaluate the diagnostic efficacy of a new blood test, Phadiatop Infant, in detecting IgE sensitisation to food and inhalant allergens among children at 2 years of age.


METHODS
Children (n = 239) were followed prospectively from birth to 2 years of age for the presence of IgE sensitisation and the development of atopic manifestations. Immunoglobulin E sensitisation was evaluated by skin prick test (SPT) and analysis of allergen-specific IgE antibodies in plasma to food and inhalant allergens. The children were classified into three groups: IgE-sensitised, non-IgE sensitised and inconclusive, depending on SPT and allergen-specific IgE results.


RESULTS
Twenty-six (11%) of the children were classified as IgE-sensitised, 182 (76%) as non-IgE sensitised and 31 (13%) as inconclusive. Phadiatop Infant was positive in 50 (21%) of the children. Ten children (4%) with identified IgE antibodies against the selected food and inhalant allergens showed negative Phadiatop Infant. Three children showed positive Phadiatop Infant but were negative in the other tests performed. These results correspond to positive and negative predictive values for Phadiatop Infant of 89 and 99%, respectively. Children with clinical symptoms of atopic diseases had significantly increased levels for Phadiatop Infant (P < 0.01).


CONCLUSIONS
Phadiatop Infant appears to be a reliable alternative to SPT and the measurement of allergen-specific IgE antibodies in plasma for detecting clinically important IgE sensitisation among children at 2 years of age.
Ballardini
N
N
Sachs' Children's Hospital, South Hospital, Karolinska Institutet, Stockholm, Sweden.
Nilsson
C
C
Nilsson
M
M
Lilja
G
G
D000367:Age Factors; D000485:Allergens / Q000009:adverse effects / Q000276:immunology; D000888:Antibodies, Anti-Idiotypic / Q000097:blood*; D002675:Child, Preschool; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D007114:Immunization; D007073:Immunoglobulin E / Q000276:immunology*; D007159:Immunologic Tests / Q000379:methods; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016017:Odds Ratio; D011446:Prospective Studies; D012372:ROC Curve; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012882:Skin Tests / Q000379:methods*; D018709:Statistics, Nonparametric
D000485:Allergens; D000888:Antibodies, Anti-Idiotypic; D007073:Immunoglobulin E