Accuracy of specific IgE in the prediction of asthma: development of a scoring formula for general practice.
BACKGROUND
For the diagnosis of asthma in young children, GPs have to rely on history taking and physical examination, as spirometry is not possible. The additional diagnostic value of specific immunoglobulin E (IgE) to inhalent allergens remains unclear.


OBJECTIVE
To assess the predictive accuracy of specific IgE to cat, dog, and/or house dust mites in young children for the subsequent development of asthma at the age of 6 years.


METHODS
Prospective follow-up study.


METHODS
Seventy-two general practices.


METHODS
A total of 654 children, aged 1-4 years, visiting their GPs for persistent coughing (>/= 5 days), were tested for IgE antibodies by radio allergosorbent testing (RAST). Parents completed a questionnaire on potential risk indicators. Those children who showed an IgE-positive status (12.7%) and a random sample of those with an IgE-negative status (<0.5 U/ml) were followed up to the age of 6 years when the asthma status was established. The main outcome measure was asthma at the age of 6 years (combination of both symptoms and/or use of asthma medication, and impaired lung function).


RESULTS
Addition of RAST results to a prediction model based on age, wheeze, and family history of pollen allergy increased the area under the receiver operating characteristic (ROC) curve from 0.76 to 0.87. Furthermore, RAST improved patient differentiation as indicated by a change in the range of asthma probabilities from 6-75% before the IgE test, to 1-95% after the IgE-test.


CONCLUSIONS
Sensitisation to inhalant allergens in 1-4-year-olds, as shown by RAST, is a useful diagnostic indicator for the presence of asthma at the age of 6 years, even after a clinical history has been obtained. This model should preferably be validated in a new population before it can be applied in practice.
Eysink
Petra E D
PE
Department of General Practice, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
ter Riet
Gerben
G
Aalberse
Rob C
RC
van Aalderen
Wim M C
WM
Roos
Carel M
CM
van der Zee
Jaring S
JS
Bindels
Patrick J E
PJ
D000485:Allergens / Q000009:adverse effects*; D000818:Animals; D001249:Asthma / Q000175:diagnosis / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D002415:Cats / Q000276:immunology; D002675:Child, Preschool; D015331:Cohort Studies; D004285:Dogs / Q000276:immunology; D004391:Dust / Q000276:immunology; D005194:Family Practice; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007223:Infant; D008297:Male; D008925:Mites / Q000276:immunology; D011237:Predictive Value of Tests; D011446:Prospective Studies
D000485:Allergens; D015415:Biomarkers; D004391:Dust; D007073:Immunoglobulin E
Pediatr Allergy Immunol. 2004 Jun;15(3):230-3
15209955
Lancet. 2003 Mar 29;361(9363):1071-6
12672309
Clin Allergy. 1977 May;7(3):235-43
908121
Br Med J (Clin Res Ed). 1983 Apr 16;286(6373):1256-8
6404414
Allergy. 1992 Aug;47(4 Pt 2):431-5
1456415
Respir Med. 1994 May;88(5):373-81
8036306
N Engl J Med. 1995 Jan 19;332(3):133-8
7800004
Allergy. 1994 Dec;49(10):843-7
7709993
Eur Respir J. 1995 Mar;8(3):483-91
7789502
Am J Respir Crit Care Med. 1996 Apr;153(4 Pt 1):1259-65
8616551
Stat Med. 1996 Feb 28;15(4):361-87
8668867
JAMA. 1997 Feb 12;277(6):488-94
9020274
Eur Respir J. 1998 Jul;12(1):1-2
9701404
Acta Paediatr. 1999 Aug;88(8):827-34
10503680
Allergy. 2002;57 Suppl 74:32-41
12371911
Allergy. 2002;57 Suppl 74:42-7
12371912
Pediatrics. 2003 Mar;111(3):e255-61
12612281
J Allergy Clin Immunol. 1972 Mar;49(3):189-91
4622102