title: Relationship between increased relative birthweight and infections during pregnancy in children with a high-risk diabetes HLA genotype.
abstract: OBJECTIVE
  Children with high-risk type 1 diabetes HLA genotype have increased risk of high relative birthweight (HrBW), while cord blood islet autoantibodies decrease the risk. As gestational infections may affect offspring type 1 diabetes risk, the aims were to test whether: (1) children of mothers reporting gestational infections have increased HrBW; (2) gestational infections explain islet autoantibody reduction of HrBW; and (3) gestational infections affect the association between HLA and HrBW.
  
  
  METHODS
  HLA genotypes and autoantibodies to glutamic acid decarboxylase, insulinoma-associated protein 2 and insulin were determined in cord blood of children born to non-diabetic mothers in the Diabetes Prediction in Skåne (DiPiS) study. Mothers reported gestational infections when the child was 2 months old.
  
  
  RESULTS
  Fever or gastroenteritis during pregnancy was reported by 2,848/19,756 mothers (14%); 339 in more than one trimester. Children whose mothers reported infections had increased risk of HrBW (p = 0.0003), particularly in the absence of cord blood islet autoantibodies (interaction between HrBW, islet autoantibodies and infections, p = 0.0005). The effect on HrBW by high-risk HLA-DQ2/8 was aggravated by infections in more than one trimester (odds ratio [OR] = 5.24; p = 0.003) (interaction; p = 0.022). When infections were reported, cord blood islet autoantibodies decreased HrBW (OR = 0.34; p = 0.0002).
  
  
  CONCLUSIONS
  This study revealed that: (1) gestational fever, gastroenteritis, or both, increased the risk of HrBW; (2) cord blood islet autoantibodies decreased the risk of HrBW only in combination with infections; and (3) infections aggravated the association between HLA-DQ2/8 and HrBW. These data suggest an interaction between HLA, gestational infections, islet autoantibodies and fetal growth.
authors.affiliation: Department of Clinical Sciences, University Hospital MAS, Lund University, 205-02 Malmö, Sweden. helena.larsson@med.lu.se
authors.forename: H E
authors.initials: HE
authors.lastname: Larsson
authors.forename: K
authors.initials: K
authors.lastname: Lynch
authors.forename: B
authors.initials: B
authors.lastname: Lernmark
authors.forename: G
authors.initials: G
authors.lastname: Hansson
authors.forename: A
authors.initials: A
authors.lastname: Lernmark
authors.forename: S-A
authors.initials: SA
authors.lastname: Ivarsson
mesh_terms: D001323:Autoantibodies / Q000097:blood; D001724:Birth Weight; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D047109:Fetal Development; D005759:Gastroenteritis / Q000453:epidemiology; D005838:Genotype; D005968:Glutamate Decarboxylase / Q000276:immunology; D006680:HLA Antigens / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D007239:Infections / Q000196:embryology* / Q000453:epidemiology*; D007527:Isoenzymes / Q000276:immunology; D011247:Pregnancy; D011248:Pregnancy Complications
chemical_list: D001323:Autoantibodies; D006680:HLA Antigens; D007527:Isoenzymes; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2