Rosie Vincent1,2, Stephanie J MacNeill3, Tom Marrs4,5, Joanna Craven6, Kirsty Logan7, Carsten Flohr8, Gideon Lack9,10,11, Suzana Radulovic4,5, Michael R Perkin12, Matthew J Ridd1,13. 1. Population Health Sciences, University of Bristol, Bristol, UK. 2. Dermatology, Bristol Royal Infirmary, University Hospital Bristol and Weston NHS Foundation Trust, Bristol, UK. 3. Department of Medical Statistics, Bristol Trials Centre, University of Bristol, Bristol, UK. 4. Department of Paediatric Allergy, Children's Allergies, Evelina London, Guy's and St Thomas' Hospital NHS Foundation Trust, London, UK. 5. Department of Paediatric Allergy, Faculty of Life Sciences and Medicine, King's College London, London, UK. 6. King's College London, London, UK. 7. Paediatric Allergy Research Group, Department of Women and Children's Health, School of Life Course Sciences, Kings College London, London, UK. 8. Unit for Population-Based Dermatology Research, St John's Institute of Dermatology, St Thomas' Hospital, London, UK. 9. Department of Paediatric Allergy, King's College London, London, UK. 10. Children's Allergy Clinical Academic Group, KHP Institute of Women and Children's Health at Evelina London, Guy's & St. Thomas' NHS Foundation Trust, London, UK. 11. Paediatric Allergy Group, Department of Women and Children's Health, Peter Gorer Department of Immunobiology, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, St Thomas' Hospital, London, UK. 12. Population Health Research Institute, St George's, University of London, London, UK. 13. Department of Primary Health Care, Population Health Sciences, University of Bristol, Bristol, UK.
Abstract
BACKGROUND: Non-IgE-mediated Cow's Milk Allergy (CMA) has a prevalence of less than 1% in children. Guidelines developed to help non-specialists diagnose CMA may lead to misattribution of normal symptoms and contribute to overdiagnosis of CMA. We sought to establish the frequency of symptoms during infancy associated with non-IgE-mediated CMA, using the international Milk Allergy in Primary Care (iMAP) guideline as representative of CMA guidelines more generally. METHOD: Secondary analysis of the Enquiring About Tolerance (EAT) randomized controlled trial (ISRCTN 14254740; 1303 exclusively breastfed 3-month-old healthy infants). Key outcomes were ≥2 iMAP symptoms associated with 'mild-moderate' and 'severe' non-IgE-mediated CMA. RESULTS: Whilst breastfeeding and parental atopy rates were higher than the general population, participants were otherwise similar to the population of England and Wales. Two or more non-IgE CMA symptoms were reported by 25% families for mild-moderate and 1.4% for severe symptoms each month between ages 3 and 12 months, peaking at 38% with ≥2 mild-moderate and 4.3% ≥2 severe symptoms at three months, when participants were not directly consuming cow's milk. 74% of participants reported ≥2 mild-moderate symptoms and 9% ≥2 severe symptoms in at least one month during this period. At six months there was no evidence of difference in the proportion of children with ≥2 symptoms between those consuming (29.5% mild-moderate, 1.8% severe) and not consuming cow's milk (35.3% mild-moderate, 2.2% severe). Mean monthly reporting of ≥2 symptoms was also no different between those with (15.8% mild-moderate, 1.1% severe) or without eczema at baseline (16.7% mild-moderate, 1.3% severe). CONCLUSIONS: Guideline-defined symptoms of non-IgE-mediated CMA are very common in infants. Guidelines may promote milk allergy overdiagnosis by labelling normal infant symptoms as possible milk allergy.
BACKGROUND: Non-IgE-mediated Cow's Milk Allergy (CMA) has a prevalence of less than 1% in children. Guidelines developed to help non-specialists diagnose CMA may lead to misattribution of normal symptoms and contribute to overdiagnosis of CMA. We sought to establish the frequency of symptoms during infancy associated with non-IgE-mediated CMA, using the international Milk Allergy in Primary Care (iMAP) guideline as representative of CMA guidelines more generally. METHOD: Secondary analysis of the Enquiring About Tolerance (EAT) randomized controlled trial (ISRCTN 14254740; 1303 exclusively breastfed 3-month-old healthy infants). Key outcomes were ≥2 iMAP symptoms associated with 'mild-moderate' and 'severe' non-IgE-mediated CMA. RESULTS: Whilst breastfeeding and parental atopy rates were higher than the general population, participants were otherwise similar to the population of England and Wales. Two or more non-IgE CMA symptoms were reported by 25% families for mild-moderate and 1.4% for severe symptoms each month between ages 3 and 12 months, peaking at 38% with ≥2 mild-moderate and 4.3% ≥2 severe symptoms at three months, when participants were not directly consuming cow's milk. 74% of participants reported ≥2 mild-moderate symptoms and 9% ≥2 severe symptoms in at least one month during this period. At six months there was no evidence of difference in the proportion of children with ≥2 symptoms between those consuming (29.5% mild-moderate, 1.8% severe) and not consuming cow's milk (35.3% mild-moderate, 2.2% severe). Mean monthly reporting of ≥2 symptoms was also no different between those with (15.8% mild-moderate, 1.1% severe) or without eczema at baseline (16.7% mild-moderate, 1.3% severe). CONCLUSIONS: Guideline-defined symptoms of non-IgE-mediated CMA are very common in infants. Guidelines may promote milk allergy overdiagnosis by labelling normal infant symptoms as possible milk allergy.