Endocrine Abstracts

Introduction: One of the autoimmunenon-diabetic hypoglycemia (NDH) causes isthe antibodies to insulinreceptor (AB-rIRI) formation and/orinsulin resistance type B (TBIR).

Objectives: To determine the prevalence of increased AB-rIRI level in patients with suspected NDH of different genesis and in healthy individuals; to determine significance of AB-rIRI investigation in NDH diagnosis.

Methods: In a prospective study we determined AB-rIRI (reference 0–3,65 ng/ml) and IRI at the beginning of fasting test in 104 patients aged 18–80 with suspected NDH. According to results, patients were divided into 4 groups: with insulinoma (group 1; n = 49), hyperinsulinemic hypoglycemia of other genesis(group 2; n = 12), hypoinsulinemic hypoglycemia (group 3; n = 13), withouthypoglycemia (group 4). 10 healthyindividualswereincludedingroup 4 (n = 40). Each group was divided into subgroups with (A) and without (B) high level of AB-rIRI. In subgroup A we selected subgroup C, in which AB-rIRI level in dynamics (in3,5 months)was determined.

Results: TBIR was not revealed.

High AB-rIRI was revealed in 15.8% (n = 18) of participants. In group 1 high level of AB-rIRI (Me 4.78 ng/ml [min 3.92; max 10.59]) was confirmed in 39% of cases (n = 7), in group 2 in 17% (n = 3; Me 4.16 ng/ml [min 3.77; max 12.3]), in group 3 in 11% (n = 2; Me 14.84 ng/ml [min 6.46; max 23.21]), in group 4 in 33% (n = 6; Me 7.97 ng/ml [min 3.68; max 17.26]). Frequency of AB-rIRI carriage in patients with NDH consisted 16% (n = 12), in group 4–15% (n = 6). When comparing AB-rIRI levels in subgroups A there were no significant differences (P = 0.52). AB-rIRI level in all patients of subgroup 1C (n = 4) was normal after surgery. Insubgroups 2C (n = 1) and 3C (n = 1) AB-rIRI levels were high, in subgroup 4C (n = 2) AB-rIRI levels were significantly higher (P = 0.028): Me 16.84 ng/ml [min 15.018; max 18.661]. Wecontinuethepatients’ observation.

Comparative analysis ingroups 2–4 revealed that in subgroups Aclinical and laboratory signs of insulinresistance occurred significantly more often (P = 0.02).

Conclusion: The AB-rIRI carriage is not so rare and probably has multi factorial etiology. It is not excluded that patients-carriers are in latent phase of TBIR, so they need careful observation, AB-rIRI’smechanism of action and pathogenesis of formationrequires data accumulation and further study. Given the equivalent increase of AB-rIRI in patients as in healthy individuals, analysis of this parameter in NDH primary diagnosisis inexpedient.

Funding: The grant of Russian Science Foundation (project 17-75-30035).