Endocrine Abstracts

Background: The association of antiphospholipid syndrome (APS) with various endocrine disorders is already known. However, data on the influence of thyroid autoantibodies and/or disorders of thyroid function on the expression of classical APS manifestations are rather limited.

Objectives: The aim of this investigation was to evaluate the impact of thyroid autoimmunity and dysfunction on frequency of recurrent miscarriages in patients with primary antiphospholipid syndrome (pAPS).

Methods: The study included 62 female patients with pAPS (mean age 43.32±11.10 years), classified according to the category of antiphospholipid antibodies (aPL) into four groups: I (with more than one aPL) – 41 patients (66%); IIa (isolated presence of lupus anticoagulant) – five patients (8%); IIb (isolated presence of anticardiolipin antibodies) – 12 patients (19.5%) and IIc (isolated presence of anti-beta two GPI antibodies) – four patients (6.5%). All patients were screened for the presence of thyroid autoimmunity (anti-thyroglobulin antibody (TgAb), anti-thyroid peroxidase antibody (TPOAb) and thyroid receptor antibody (TRAb)) and thyroid dysfunction (thyroid stimulating hormone (TSH) and free thyroxine (fT4)). Data on recurrent miscarriages were obtained from the patients’ medical records.

Results: Recurrent miscarriages were documented in 68% of the category I patients, all patients in the category IIa, 67% of the category IIb patients and 50% of those from the category IIc. Thyroid autoimmunity was significantly more prevalent among patients with documented recurrent miscarriages (16/44, 36%), compared with patients with no such data (4/18, 22%) (P<0.01). Among patients with history of recurrent miscarriages, ten patients (23%) had overt hypothyroidism, requiring levo-thyroxine replacement, while none of patients without previous miscarriages had any disorder of thyroid function.

Conclusion: Well-known association between autoimmune disorders, in the case of APS and thyroid autoimmunity, opens controversial issue of possibility of their synergistic, additive or potentiating effects on pregnancy complications as one of the classic manifestations of these relatively common syndromes.