VITAMIN D SERUM LEVELS IN ARGENTINIAN MYASTHENIA GRAVIS PATIENTS. AN UPDATE OF A LARGER COHORT.

JUSTO, ME; ALDECOA, M; AGUIRRE, F; CELA, EM; VILLA, A; LEONI, J; GONZÁLEZ MAGLIO, DH; PAZ, ML

Congreso; LXVII Reunión Científica Anual de la Sociedad Argentina de Inmunología; 2019

Myasthenia Gravis (MG) is an autoimmune disease mediated by anti-acetylcholine receptor autoantibodies (ACRA) mainly, whose production is T cell dependent and controlled by regulatory T lymphocytes (Tregs), which are impaired in MG patients. Vitamin D (VitD) has immunomodulatory effects, stimulating Tregs and inhibiting effector T cells. A controversial association between VitD deficiency and MG development and severity has been established. We compared 25-OH-VitD serum levels in 66 diagnosed MG patients and 25 healthy volunteers (hv) and related them with the severity of the disease and other biomarkers, in an Argentinian cohort. We collected samples equally distributed through the year and balanced according to sunlight exposure and VitD intake through a validated questionnaire. We measured: 25-OH-VitD (chemiluminescence), C3 and C4 (RID), C5a (ELISA) and ACRA (RIA).There were no statistically significant (ss) differences in 25-OH-VitD mean serum levels between patients and hv, neither between basal and exacerbated patients. Deficient levels of 25-OH-VitD (