IgE-mediated allergy to an elemental amino acid formula.
Unusual soy oil allergy
Article first published online: 21 MAR 2002
Volume 57, Issue 3, pages 266–267, March 2002
How to Cite
Moneret-Vautrin, D. A., Morisset, M., Flabbee, J., Kanny, G., Kirch, F. and Parisot, L. (2002), Unusual soy oil allergy. Allergy, 57: 266–267. doi: 10.1034/j.1398-9995.2002.1n3528.x
- Issue published online: 21 MAR 2002
- Article first published online: 21 MAR 2002
- elemental amino acid formula;
- non IgE-mediated allergy;
- soy oil
Thomas was born uneventfully from a normal pregnancy and fed with milk formula. At one month of age the first signs of the IgE-associated subgroup (AD) of the atopic eczema/dermatitis syndrome (AEDS) (1) led to a prick test, which was positive to milk: 12 mm (codeine: 3 m). The pediatrician substituted soya milk but the AD worsened, and at five months of age the atopic dermatitis severity score (SCORAD) was 45 (2). Prick tests to cow's milk and soya milk were negative, so diet was not modified till he reached 10 months of age. At this time AD was generalized and patch tests were carried out (3). Positivity to soya milk led to its withdrawal. Despite feeding with a casein extensive hydrolysate, the infant failed to improve: daily rashes were accompanied by vomiting and diarrhoea. An amino acid formula (AAF) was prescribed. The digestive symptoms resolved but SCORAD remained at 34.
This AAF contains a soy lipidic emulsion. Skin tests with separate components of AAF were carried out. Patch tests were positive to the soy oil emulsion only. An oral challenge to the soy oil emulsion (30 ml in 240 ml of water) induced a rash four hours later.
The AAF was stopped for three days. A partial regression of the inflammatory state was observed. Conversely, the reintroduction of 240 ml of AAF on the fourth and fifth days provoked a rash in the afternoon of day four, and exacerbation of the eczema on day five. SCORAD rose from 27 to 45.
Neocate Advance® that does not contain soy lipidic emulsion was substituted. A complete recovery was observed six weeks later.
Following IgE-dependent allergy to cow's milk, the child developed T cell mediated allergy to soy (1). In such cases, replacing cow's milk with extensive hydrolysates (EH) is advised (4). However, allergy to casein EH occurs in 8% of cases (5). Substitution with AAF is usually effective, and safety is excellent (6). A case of allergy to AAF was attributed to contamination (7).
The role of soy oil was suspected on the basis of the T cell-mediated allergy to soy. Indeed, allergens in soy lecithins and soy oil have been evidenced (8,9) and allergic reactions to soy lecithin have been observed (10).
AAFs are used specifically for infants presenting with severe CMA, often associated with multiple food intolerance or with allergy to hydrolysates. These infants can be considered to be the most atopic subjects, reacting to traces of allergens. It would seem advisable to replace the soy oil by other vegetable lipids in AAFs.
- 9et al. Soy allergens are detected in some edible soy oils. J Allergy Clin Immunol 2001; 107:S188., , , , , ,
Accepted for publication 6 November 2001