Distribution of autoantibodies to glutamic acid decarboxylase across the spectrum of diabetes mellitus seen in South Africa

Abstract

Auto-immune beta-cell destruction has an important role in the pathogenesis of Type 1 DM amongst African patients. However, Type 2 African DM patients and other diabetes subtypes are largely GAD-AB-negative.

Islet cell-associated autoantibodies in Ethiopians with diabetes mellitus

“…In Caucasian population, the prevalence of islet cell-associated antibodies in recently diagnosed subjects with T1DM ranged from 80% to 97% (Diabetes Prevention Trial -Type 1 Diabetes Study Group, 2002;Landin-Olsson et al, 1992;Notkins & Lernmark, 2001). The prevalence in our study was comparable to that of Asians (Lee, Ng, Thai, Lui, & Loke, 2001;Todd, Ng, Lui, & Thai, 2004;Zimmet et al, 1993) where it was reported at 5-40% and Africans (Hawa et al, 2005;Lutale et al, 2007;Oli et al, 1981;Panz et al, 2000) which ranged 7-44%, including what was reported in Ethiopia in the 1980s and in 2011 (Gill et al, 2011;Peters et al, 1986). We think that part of the reason why the antibody positivity in our T1DM patients was relatively lower is the fact that most of our T1DM patients were not newly diagnosed as indicated by the mean duration of diabetes.…”

Latent autoimmune diabetes amongst adults with type 2 diabetes in a Nigerian tertiary hospital

“…The UKPDS study, which is one of the largest studies done in patients with type 2 DM, reported a prevalence of 9.4% [9]. Studies conducted amongst Africans have reported the prevalence of GADA in CT2DM as 2.5% amongst South Africans, while in Tanzania the prevalence was 5.3% [10,11]. In a study done in West Africa on the genetics of diabetes, with Ghana and Nigeria as centres, 10% of the patients with CT2DM were found to be positive for GADA [12].…”

Immunological and C-peptide studies of patients with diabetes in northern Ethiopia: existence of an unusual subgroup possibly related to malnutrition

“…In one European study, two-thirds of a type 1 diabetes cohort were still positive for either islet cell antibodies or GADA at 10 years after diagnosis [26]. Also, type 1 diabetic patients elsewhere in Africa, including urban Ethiopia, have been shown to be positive for GADA or islet cell antibodies [27,28]. Accepting these limitations, our revised groupings give a much more expectable proportion of type 1 diabetes patients at 17%, with type 2 diabetes comprising 47% and the 'uncertain' group 36%.…”