title: Onset of type 1 diabetes mellitus in two patients with maturity onset diabetes of the young.
abstract: The association between maturity onset diabetes of the young (MODY) and type 1 diabetes mellitus (T1DM) has been rarely described. We report two patients affected by MODY who developed T1DM. Case 1: a 4-yr-old girl referred for glycosuria presented hemoglobin A1c (HbA1c) of 6.6%. Islet cell antibodies (ICA) and anti-glutamic acid decarboxylase (GADA) were initially negative. As her father, uncle and grandmother showed mild hyperglycemia, they were screened for MODY 2. A novel mutation in glucokinase gene was found in the family. Few months later, her glycemic control worsened consistently and she required insulin treatment. A high titer of GADA and ICA was then detected. Six years afterwards insulin requirement is 0.8 U/kg and HbA1c 6.7%. Case 2: a 15-yr-old boy treated for growth hormone deficiency was found with a blood glucose level of 106 mg/dL. HbA1c was 7.2%, ICA and GADA were negative. Family history was positive for autoimmune diseases and type 2 diabetes mellitus. The patient was investigated for MODY 2 and MODY 3, and a mutation of hepatocyte nuclear factor-1 alpha gene was found. The same mutation was found in the mother who had never been referred for hyperglycemia. After 1 yr, due to an unjustified worsening of the metabolic control, autoimmunity was again investigated and a mild positivity was found. He then required insulin therapy and after 5 yr current HbA1c was 8.2%. The diagnosis of MODY does not exclude the risk of developing T1DM. Therefore autoimmunity should be investigated when ordinary treatments fail and metabolic control unexpectedly worsens.
authors.affiliation: Department of Pediatrics, S. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Maltoni
authors.forename: Stefano
authors.initials: S
authors.lastname: Zucchini
authors.forename: Mirella
authors.initials: M
authors.lastname: Scipione
authors.forename: Vilma
authors.initials: V
authors.lastname: Mantovani
authors.forename: Silvana
authors.initials: S
authors.lastname: Salardi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cicognani
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D001323:Autoantibodies / Q000097:blood / Q000276:immunology; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics*; D005260:Female; D005941:Glucokinase / Q000235:genetics*; D005968:Glutamate Decarboxylase / Q000276:immunology; D006442:Glycated Hemoglobin / Q000032:analysis; D051538:Hepatocyte Nuclear Factor 1-alpha / Q000235:genetics*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D009154:Mutation
chemical_list: D001323:Autoantibodies; D005941:Glucokinase; D005968:Glutamate Decarboxylase; D006442:Glycated Hemoglobin; D051538:Hepatocyte Nuclear Factor 1-alpha; D007004:Hypoglycemic Agents; D007328:Insulin; C496487:HNF1A protein, human; C517652:hemoglobin A1c protein, human; C024211:islet cell antibody