Organ-specific antibodies in LADA patients for the prediction of insulin dependence

ABSTRACT

Aim of the study: The aim of the present study was to define the frequency of organ-specific and non-organ-specific autoantibodies in a cohort of Latent Autoimmune Diabetes in Adults (LADA) patients and to test whether multiple antibodies positivity could be a predictor of early insulin dependence. Materials and methods: We enrolled 210 LADA and 210 type 2 diabetes mellitus (T2D) patients. In all subjects anti-islet antigen-2 (IA-2Ab), anti-thyroperoxidase (TPOAb), anti-zinc transporter 8 (ZnT8Ab), anti-nuclear (ANA), anti-parietal cell (APCA), anti-smooth muscle (ASMA), anti-mitochondrial (AMA), anti-liver kidney microsomes (LKM), and anti-reticulin (ARA) circulating antibodies were assessed. Results: The frequency of TPOAb, ZnT8Ab, APCA, and IA-2Ab positivity was, respectively, detected in 40.0%, 32.4%, 24.7%, and 9.5% of LADA patients, whereas their frequency was significantly lower in T2D patients (11.4%, 1.9%, 9.5%, and 0.0%, respectively, p < 0.001). The frequency of ANA was the same in both groups whereas the frequency of ASMA, ARA, AMA, and LKM was very low (range 0.0–3.3%). The presence of TPOAb associated with ZnT8Ab, IA-2Ab, or APCA allows one to predict the progression of disease with a high specificity but low sensibility. Conclusions: LADA patients show an increased frequency of organ- and non-organ-specific antibodies. Consequently, a screening is worthwhile in these patients. The simultaneous presence of TPOAb with ZnT8, IA-2Ab, or APCA may help differentiate clinical phenotypes and predict faster insulin dependence in LADA patients.

KEYWORDS:

• APCA
• LADA
• organ specific autoantibodies
• TPOAb
• ZnT8Ab

Acknowledgments

A.P. Delitala and G.M. Pes contributed equally to this work.

Declaration of interest

The authors reported no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Funding

This work was funded by a grant from Fondazione Banco di Sardegna (“Visceral obesity, type 2 diabetes mellitus, and LADA. The role of adipocytokines” to Giuseppe Delitala, and in part from Regione Autonoma della Sardegna, Fundamental Research Programme, L.R. 7/2007 “Promotion of the scientific research and technological innovation in Sardinia” under grant agreement CRP- 59886 AMBROSIA Project, and by Fondazione Banco di Sardegna (Prot. U267.2013/AI.197.MGB Prat. 2013.0030).

Additional information

Funding

This work was funded by a grant from Fondazione Banco di Sardegna (“Visceral obesity, type 2 diabetes mellitus, and LADA. The role of adipocytokines” to Giuseppe Delitala, and in part from Regione Autonoma della Sardegna, Fundamental Research Programme, L.R. 7/2007 “Promotion of the scientific research and technological innovation in Sardinia” under grant agreement CRP- 59886 AMBROSIA Project, and by Fondazione Banco di Sardegna (Prot. U267.2013/AI.197.MGB Prat. 2013.0030).