P-115: A rare triad in autoimmune polyendocrine syndrome type 2: early-onset type 1 diabetes, prepubertal oophoritis and biphasic thyroid disease
V R d A Borges, M M R do Valle, J A O C Machado, G Panuci, R S Berardo, C T da Fonseca, L A Cordeiro, C M Borschvier, S Esch, B S Pugliese, H M B L BerbaraAbstract
Introduction
Polyglandular autoimmune syndrome (PAS) occurs in approximately 4–8.5% of children with type 1 diabetes (T1D). The most frequent associated conditions include autoimmune thyroid disease, celiac disease, and primary adrenal insufficiency. Primary ovarian insufficiency (POI) due to autoimmune oophoritis is uncommon in pediatric T1D but may significantly affect metabolic control and pubertal development.
Objectives
To report a case of early-onset POI in an adolescent with T1D and PAS, highlighting its impact on glycemic stability
Methods
Retrospective chart review.
Results
A 14-year-old female was diagnosed with T1D at 11 months and managed with continuous subcutaneous insulin infusion (CSII). At 11 years, she developed Graves’ disease (suppressed TSH, elevated FT4, positive TRAb), with worsening glycemic variability during methimazole therapy. At 12 years, growth deceleration prompted evaluation, revealing hypergonadotropic hypogonadism (FSH 122 IU/L, LH 46 IU/L, undetectable estradiol) and 46, XX karyotype, consistent with POI. Although anti-ovarian and 21-hydroxylase autoantibodies were negative, autoimmune oophoritis was considered the most likely etiology. Menarche occurred at 13 years following hormonal induction. Subsequently, she developed autoimmune hypothyroidism (TPOAb >600 IU/mL), requiring levothyroxine. Evaluation for adrenal insufficiency showed low peak cortisol during hypoglycemia (5 µg/dL) but normal basal levels (15.8 µg/dL), allowing expectant management. Tissue antitransglutaminase antibody was negative. Currently, HbA1c is 9.4% on non-closed-loop CSII.
Conclusions
This case illustrates how PAS-related endocrinopathies, including POI and fluctuating thyroid dysfunction, can exacerbate glycemic instability in pediatric T1D. Severe glycemic variability, delayed puberty, or impaired growth should prompt systematic screening for associated autoimmune diseases. Prompt recognition optimizes glycemic management and multidisciplinary care.