Prevalence and characteristics of celiac disease in South African patients with type 1 diabetes mellitus: Results from the Durban Diabetes and Celiac Disease Study.

BACKGROUND AND AIM: The aim of this study was to assess the prevalence and characteristics of celiac disease (CD) in all patients with type 1 diabetes mellitus attending a tertiary adult diabetes clinic in Durban, South Africa. METHODS: This was a cross-sectional observational study that screened 202 patients; of these, 56.4% were African (Black), 31.7% Asian Indian, 4.5% White, and 7.4% mixed race. Demographic data, symptoms, and anthropometry were documented. Blood tests included anti-tissue transglutaminase antibody (tTG), anti-endomysial antibody (EMA), and anti-gliadin antibody (AGA). Endoscopy and duodenal biopsy were performed in patients with celiac antibodies. Diagnosis of CD was based on the modified Marsh classification. RESULTS: Mean age and mean duration of diabetes were 26.4 ± 11.4 and 10.7 ± 9.1 years, respectively. Celiac antibodies were found in 65 (32.2%) patients: EMA 7.4%, tTG immunoglobulin A (IgA) 8.4%, tTG immunoglobulin G 1.9%, AGA IgA 18.3%, and AGA immunoglobulin G 21.8%. Histological evidence of CD was found in 5.9% (n = 12/202): 2.5% were classed as definite CD (Marsh 3) and 3.4% as potential CD (Marsh 1). None of the patients with CD were symptomatic. The sensitivity of AGA IgA, EMA, and tTG IgA antibodies for detecting histologically proven CD was 66.7%, 50.0%, and 41.7%, respectively. CONCLUSION: The prevalence of CD was similar to reports from western countries. No ethnic specific differences were noted. CD was silent in all patients in this study. The sensitivity of EMA and tTG antibodies was poor and merits further evaluation as screening tools for CD in South African patients with type 1 diabetes mellitus.

High prevalence of antithyroid peroxidase and antiparietal cell antibodies among patients with type 1 diabetes mellitus attending a tertiary diabetes centre in South Africa.

OBJECTIVE: Data on the prevalence of autoimmune thyroid disease (AITD) and gastric autoimmunity in type 1 diabetes mellitus (T1DM) in Africa are limited. The aim of this study was to assess the prevalence of antithyroid peroxidase (TPO-A) and antiparietal cell antibody (PCA) in patients with T1DM at a tertiary diabetes clinic in Durban, South Africa. RESEARCH DESIGN AND METHODS: This was a cross-sectional observational study among subjects attending the adult T1DM clinic at Inkosi Albert Luthuli Hospital. Information about history and clinical examination was collected. Blood tests included glutamic acid decarboxylase antibody (GADA), TPO-A, PCA, vitamin B12, folate, ferritin, thyroid stimulating hormone (TSH), free thyroxine, lipids and HbA1c. RESULTS: A total of 202 (M:F, 90:112) patients were recruited. The ethnic composition was African (black) (56.4%; n=114), Indian (31.7%; n=64), white (4.5%; n=9) and coloured (mixed race) (7.4%; n=15). Mean age and mean duration of diabetes were 26.4±11.4 and 10.7±9.1 years, respectively. Mean body mass index was 21.6±6.3 kg/m2. GADA was positive in 63.37% (n=128). The prevalence of TPO-A was 18.9% (n=39) and PCA 8.9% (n=17). The prevalence of overt hypothyroidism, subclinical hypothyroidism and Graves' disease was 10.9%, 2.5% and 1.5%, respectively; vitamin B12 deficiency was noted in 3.5% (n=7) and iron deficiency in 19.3% (n=39). CONCLUSIONS: Among patients with T1DM in this study, there was a high prevalence of coexistent AITD and gastric autoimmunity. Screening for hypothyroidism and thyroid autoimmunity should be undertaken in all patients at initial presentation. However, to assess the feasibility and optimal timing of subsequent testing in the African setting with limited resources, more collaborative research with longitudinal studies is required.