title: ATP4A autoimmunity in pediatric patients with type 1 diabetes and its relationship to blood count, iron metabolism, and vitamin B12.
abstract: We aimed to assess the prevalence of autoantibodies against the 4A subunit of the gastric proton pump (ATP4A) in pediatric type 1 diabetes (T1D) patients and explore the relationship between ATP4A positivity and blood cell count, iron turnover, and vitamin B12 concentration.
  
  
  
  The study included 94 (59% female) T1D children (aged 12.5 ± 4.1 years, T1D duration 4.2 ± 3.6 years, HbA1c 7.3 ± 1.5% (57 ± 12.6 mmol/mol) with no other autoimmune diseases.
  
  
  
  ATP4A antibodies were measured in T1D patients using a radioimmunoprecipitation assay. Blood cell count, iron concentration, total iron binding capacity, ferritin, transferrin, hepcidin, and vitamin B12 concentration were measured in all the study participants.
  
  
  
  A total of 16 (17%) children were ATP4A positive. Serum concentrations of ferritin were significantly lower in ATP4A positive than in antibody negative subjects (P = .034). Overall the levels of ATP4A antibodies (ATP4A Index) correlated positively with the age at T1D diagnosis (r = 0.228, P = .026) and negatively with ferritin levels (r = -0.215, P = .037). In ATP4A positive patients, the ATP4A Index correlated positively with age at diagnosis (r = 0.544, P = .032) and negatively with vitamin B12 levels (r = -0.685, P = .004).
  
  
  
  ATP4A antibodies were present in a significant proportion of children with T1D. Higher ATP4A levels in T1D children are associated with lower, yet still fitting within the normal range, levels of vitamin B12, and ferritin. Routine screening of T1D children for gastric autoimmunity (ATP4A) should be considered with follow-up of those positive for vitamin B12 and iron deficiency.
authors.affiliation: Public Clinical Hospital No. 1 in Zabrze, Zabrze, Poland.
authors.forename: Agata
authors.identifier: 0000-0002-9622-4433
authors.initials: A
authors.lastname: Chobot
authors.affiliation: The Upper Silesian Center for Child Health, Katowice, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Rusak
authors.affiliation: University of Colorado Denver, Barbara Davis Center for Diabetes, Aurora, Colorado.
authors.forename: Janet
authors.initials: J
authors.lastname: Wenzlau
authors.affiliation: University of Colorado Denver, Barbara Davis Center for Diabetes, Aurora, Colorado.
authors.forename: Howard
authors.initials: H
authors.lastname: Davidson
authors.affiliation: School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Katowice, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Adamczyk
authors.affiliation: Public Clinical Hospital No. 1 in Zabrze, Zabrze, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Krzywicka
authors.affiliation: School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Katowice, Poland.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Mazur
authors.affiliation: The Silesian University of Technology, Gliwice, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Polańska
authors.affiliation: University of Colorado Denver, Barbara Davis Center for Diabetes, Aurora, Colorado.
authors.forename: Marian
authors.initials: M
authors.lastname: Rewers
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood; D001772:Blood Cell Count; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000276:immunology*; D005260:Female; D017506:H(+)-K(+)-Exchanging ATPase / Q000276:immunology*; D006801:Humans; D007501:Iron / Q000378:metabolism; D008297:Male; D014805:Vitamin B 12 / Q000097:blood; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D007501:Iron; C000591756:ATP4A protein, human; D017506:H(+)-K(+)-Exchanging ATPase; D014805:Vitamin B 12
keywords: 
  ATP4A antibodies; ferritin; gastric autoimmunity; type 1 diabetes; vitamin B12
  