title: Islet immunity and beta cell reserve of indigenous Black South Africans with ketoacidosis at initial diagnosis of diabetes.
abstract: OBJECTIVE
  Islet immunity and beta cell reserve status were utilized to classify persons with ketoacidosis as the initial manifestation of diabetes. The clinical features of the various diabetes classes were also characterized.
  
  
  METHODS
  Prospective cross sectional study.
  
  
  METHODS
  Nelson Mandela Academic Hospital, Mthatha, Eastern Cape Province, South Africa.
  
  
  METHODS
  Indigenous Black South Africans with ketoacidosis as the initial manifestation of diabetes.
  
  
  METHODS
  Islet immunity and beta cell reserve were respectively assessed using serum anti-glutamic acid decarboxylase 65 (GAD) antibody and serum C-peptide after 1 mg of intravenous glucagon.
  
  
  METHODS
  Serum anti-GAD 65 antibody > or = 5 units/L and < 5 units/L, respectively defined anti-GAD 65 positive (A+) and negative (A-). Replete (beta+) and deplete (beta-) beta cell reserve were serum C-peptide after glucagon injection of > or = 0.5 ng/mL and < 0.5 ng/mL, respectively. The proportions of patients with A+beta-, A+beta+, A-beta- and A-beta+ and their clinical characteristics were determined.
  
  
  RESULTS
  Of the 38 males and 33 females who participated in the study, patients were categorized in various classes: A-beta+, 46.5% (n=33/ 71); A-beta-, 26.8% (n=19/71); A+beta-, 22.5% (n=16/71); and A+beta+, 4.2% (n=3/71). The ages of the various classes were: 41.8 +/- 13.8 years for A-beta+ (n=33); 36.5 +/- 14.6 years for A-beta- (n=19); and 20.6 +/- 7.1 years for the combination of A+beta- with A+beta+ (n=19) (P<.0001, P<.0001 for the combination of A+beta- and A+beta+ vs A-beta+, P=.001 for the combination of A+beta- and A+beta+ vs A-beta-and P=.2 for A-beta- vs A-beta+. The clinical features of type 2 diabetes were most prevalent in A-beta+ class while the A+beta- and A+beta+ groups had the clinical profile of type 1A diabetes.
  
  
  CONCLUSIONS
  Most of the indigenous Black South African patients with ketoacidosis as the initial manifestation of diabetes had islet immunity, beta cell reserve status and clinical profiles of type 2 diabetes.
authors.affiliation: Department of Internal Medicine, Faculty of Health Sciences, Walter Sisulu University, Mthatha, Eastern Cape Province, South Africa. chuksekpebegh@yahoo.com
authors.forename: Chukwuma
authors.initials: C
authors.lastname: Ekpebegh
authors.forename: Benjamin
authors.initials: B
authors.lastname: Longo-Mbenza
authors.forename: Ernesto
authors.initials: E
authors.lastname: Blanco-Blanco
mesh_terms: D000052:Acanthosis Nigricans / Q000276:immunology; D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood; D044383:Black People; D002096:C-Peptide / Q000097:blood; D003430:Cross-Sectional Studies; D016883:Diabetic Ketoacidosis / Q000208:ethnology / Q000276:immunology*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology; D006801:Humans; D050417:Insulin-Secreting Cells / Q000276:immunology*; D007515:Islets of Langerhans / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016036:Seroepidemiologic Studies; D013019:South Africa; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D002096:C-Peptide; D005968:Glutamate Decarboxylase