Pediatric Allergy and Immunology
ORIGINAL ARTICLE
Food allergy
Food allergy in South African children with atopic dermatitis Claudia L. Gray1, Michael E. Levin1, Heather J. Zar2, Paul C. Potter3, Nonhlanhla P. Khumalo4, Lucia Volkwyn1, Bartha Fenemore3 & George du Toit5,6 1
Division of Allergology, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa; 2Department of Paediatrics and Child Health, Red Cross War Memorial Children’s Hospital, University of Cape Town, Cape Town, South Africa; 3Allergy Diagnostic and Clinical Research Unit, Department of Medicine, Groote Schuur Hospital and University of Cape Town, Cape Town, South Africa; 4Division of Dermatology, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa; 5MRM & Asthma UK Centre in Allergic Mechanisms of Asthma, King’s College London, King’s Health Partners, London, UK; 6Department of Paediatric Allergy, Guy’s and St Thomas’ NHS Foundation Trust, London, UK
To cite this article: Gray CL, Levin ME, Zar HJ, Potter PC, Khumalo NP, Volkwyn L, Fenemore B, du Toit G. Food allergy in South African children with atopic dermatitis. Pediatr Allergy Immunol 2014: 25: 572–579.
Keywords atopic dermatitis; black Africans; food allergy; food sensitization; IgE-mediated; incremental food challenges; peanut allergy Correspondence Claudia Gray, MBChB, MSc, FRCPCH, DipAllergy, DipPaedNutrition, Department of Allergology, Red Cross War Memorial Children’s Hospital, Klipfontein Road, Cape Town, 7700, South Africa. Tel.: +27 (0) 21 5318013 Fax: +27 21 5319576 E-mail: [email protected] Accepted for publication 22 July 2014 DOI:10.1111/pai.12270
Abstract Background: The prevalence of food allergy in South Africa is unknown, but previously thought to be rare in black South Africans. This study aimed to determine the prevalence of, and risk factors for, IgE-mediated food allergy in South African children with atopic dermatitis (AD). Methodology: This was a prospective, observational study in a paediatric university hospital in Cape Town. Children with AD, aged 6 months to 10 yrs, were randomly recruited from the dermatology clinic. They were assessed for sensitization and allergy by questionnaire, skin prick tests, Immuno Solid Phase Allergen Chip (ISAC) test and incremental food challenges. Results: 100 participants (59 black Africans and 41 of mixed race) were enrolled, median age 42 months. There were high overall rates of food sensitization (66%) and food allergy (40%). Egg (25%) and peanut (24%) were the most common allergies. Black participants had comparable sensitization (69% vs. 61%) but lower allergy rates (34% vs. 46%) than mixed race participants. This was especially evident for peanut allergy (15% Blacks vs. 37% mixed race allergic to peanut, p = 0.01). Early-onset AD (
ORIGINAL ARTICLE
Food allergy
Food allergy in South African children with atopic dermatitis Claudia L. Gray1, Michael E. Levin1, Heather J. Zar2, Paul C. Potter3, Nonhlanhla P. Khumalo4, Lucia Volkwyn1, Bartha Fenemore3 & George du Toit5,6 1
Division of Allergology, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa; 2Department of Paediatrics and Child Health, Red Cross War Memorial Children’s Hospital, University of Cape Town, Cape Town, South Africa; 3Allergy Diagnostic and Clinical Research Unit, Department of Medicine, Groote Schuur Hospital and University of Cape Town, Cape Town, South Africa; 4Division of Dermatology, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa; 5MRM & Asthma UK Centre in Allergic Mechanisms of Asthma, King’s College London, King’s Health Partners, London, UK; 6Department of Paediatric Allergy, Guy’s and St Thomas’ NHS Foundation Trust, London, UK
To cite this article: Gray CL, Levin ME, Zar HJ, Potter PC, Khumalo NP, Volkwyn L, Fenemore B, du Toit G. Food allergy in South African children with atopic dermatitis. Pediatr Allergy Immunol 2014: 25: 572–579.
Keywords atopic dermatitis; black Africans; food allergy; food sensitization; IgE-mediated; incremental food challenges; peanut allergy Correspondence Claudia Gray, MBChB, MSc, FRCPCH, DipAllergy, DipPaedNutrition, Department of Allergology, Red Cross War Memorial Children’s Hospital, Klipfontein Road, Cape Town, 7700, South Africa. Tel.: +27 (0) 21 5318013 Fax: +27 21 5319576 E-mail: [email protected] Accepted for publication 22 July 2014 DOI:10.1111/pai.12270
Abstract Background: The prevalence of food allergy in South Africa is unknown, but previously thought to be rare in black South Africans. This study aimed to determine the prevalence of, and risk factors for, IgE-mediated food allergy in South African children with atopic dermatitis (AD). Methodology: This was a prospective, observational study in a paediatric university hospital in Cape Town. Children with AD, aged 6 months to 10 yrs, were randomly recruited from the dermatology clinic. They were assessed for sensitization and allergy by questionnaire, skin prick tests, Immuno Solid Phase Allergen Chip (ISAC) test and incremental food challenges. Results: 100 participants (59 black Africans and 41 of mixed race) were enrolled, median age 42 months. There were high overall rates of food sensitization (66%) and food allergy (40%). Egg (25%) and peanut (24%) were the most common allergies. Black participants had comparable sensitization (69% vs. 61%) but lower allergy rates (34% vs. 46%) than mixed race participants. This was especially evident for peanut allergy (15% Blacks vs. 37% mixed race allergic to peanut, p = 0.01). Early-onset AD (
