title: Reactions of Buckwheat-Hypersensitive Patients during Oral Food Challenge Are Rare, but Often Anaphylactic.
abstract: BACKGROUND
  Buckwheat (BW) is a common cause of life-threatening allergy in Asia. Few have examined oral food challenges (OFCs) using BW. We here describe the OFC outcomes for the diagnosis or confirmation of tolerance acquisition and clarify risk factors for positive OFCs.
  
  
  METHODS
  Between July 2005 and March 2014, we retrospectively reviewed data from children who underwent OFCs using 3,072 mg of BW protein at Sagamihara National Hospital. Children were suspected of having BW allergy because of positive results for BW-specific IgE or because they had been previously diagnosed with BW allergy owing to immediate reactions to BW.
  
  
  RESULTS
  Of 476 such patients, we analyzed 419 aged 1-17 years (median age 6.7 years). Forty-four (10.5%) reacted to the BW OFC and 24 (54.5%) experienced anaphylaxis. Among patients with suspected BW allergies (n = 369), 30 (8.1%) reacted to OFC. However, among patients with definitive BW allergies (n = 50) who underwent OFCs a median of 7.0 years after their last immediate reaction, 14 (28.0%) reacted to OFC. Among 12 patients with past anaphylactic reactions to BW, 8 exhibited tolerance to BW. A history of immediate reaction to BW and high BW-specific IgE levels were significant risk factors for a positive OFC.
  
  
  CONCLUSIONS
  BW allergies are rare among children suspected of having BW allergies due to positivity for BW-specific IgE. Most children with definitive BW allergies can tolerate BW, even after anaphylactic reactions. Nevertheless, careful observation is needed when performing BW OFCs, considering the high incidence of anaphylactic reactions.
authors.affiliation: Department of Pediatrics, Clinical Research Center for Allergy and Rheumatology, Sagamihara National Hospital, Sagamihara, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Yanagida
authors.forename: Sakura
authors.initials: S
authors.lastname: Sato
authors.forename: Kyohei
authors.initials: K
authors.lastname: Takahashi
authors.forename: Ken-Ichi
authors.initials: KI
authors.lastname: Nagakura
authors.forename: Kiyotake
authors.initials: K
authors.lastname: Ogura
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Asaumi
authors.forename: Motohiro
authors.initials: M
authors.lastname: Ebisawa
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000485:Allergens / Q000009:adverse effects / Q000276:immunology*; D000707:Anaphylaxis / Q000453:epidemiology* / Q000209:etiology; D052179:Antigens, Plant / Q000009:adverse effects / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D019612:Fagopyrum / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D007114:Immunization; D015994:Incidence; D007223:Infant; D007564:Japan; D008297:Male; D012189:Retrospective Studies; D012306:Risk
chemical_list: D000485:Allergens; D052179:Antigens, Plant