Clinical approach to the differential diagnosis between immune-mediated diabetes and type 2 diabetes in adult patients

Background. iDM/laDa is late-manifesting immune-mediated diabetes diagnosed in patients over 30 years of age. it is estimated to account for 5-10% of diabetes cases in adults. Objectives. the aim of the study was to identify the parameters implying the diagnosis of immune-mediated diabetes among adults with new-onset diabetes. Material and methods. study included patients 30-50 years of age with new-onset diabetes, hospitalised between 2014 and 2019 in the Diabetology Department. Medical history, hyperglycaemia symptoms, comorbidities, anthropometric measurements and laboratory tests were analysed. the exclusion criterion was a history of pancreatitis. Results. we analysed a group of 182 patients (mean age 38.1 5.1). iDM/laDa was diagnosed in 78 (43%) patients. in the subgroup of subjects 30-35 years of age, iDM/laDa patients constituted 50.08%, whereas in the 36-50 years of age group, this constituted 38.65% of all the patients. the iDM/laDa patients were younger, had a lower body mass and BMi, noticed symptoms of diabetes before hospitalisation and more often had other autoimmune disorders. thier c-peptide concentrations were nearly three times lower, while t2DM patients had a higher concentration of total cholesterol and triglycerides and more frequently had arterial hypertension (all p < 0.05). testing for one antibody (GaDa) allows one to diagnose 83% of iDM/laDa cases. Furthermore, determination of both GaDa and ica resulted in diagnosing autoimmune diabetes in 97% of all the patients. Conclusions. with a measurement of c-peptide concentration and GaDa detection, we could diagnose iDM/laDa with 89% sensitivity. Moreover, the inclusion of clinical features increased the sensitivity up to 93.5%. considering the age criterion, there was no significant difference between the groups of patients with iDM/laDa.