Endocrine Abstracts

Aim: Analyzing the evolution of thyroid function in thyroiditis and related disease during 1–15 years.

Materials and methods: A) Diagnostic: Hashimoto thyroiditis (HT): i) antithyroperoxydase antibodies (ATPO) cut-off 34. ii) If ATPO=normal (N), was considered thyroiditis with only antithyroglobuline antibodies (T-ATG); iii) idiopathic mixedema (IM): hypothyroidism, no ATPO, no ATG, no TRAB.

B) Patients: i) HT: 1092; T-ATG: 61; IM: 70. Women/men: HT: 1041/51; T-ATG: 58/3; IM: 59/11 (more men: P<0.001).

C) Statistic analysis: test χ².

Results: A) At the diagnostic moment. i) HT: euthyroid (EUT): 490 (~45%), hypothyroid (HOT): 443 (~40.5%), hyperthyroid (HIT): 159 (~14.6%) – from these: 141 (~89%) associated with Graves-Basedow disease (GBD)-(TRAB+; more than in T-ATG).

ii) T-ATG: EUT: 36 (59%, more than in HT), HOT: 19 (31%), HIT: 6 (9.8%) – from these: 3 (50%) associated with GBD-(TRAB+).

iii) IM: (by definition): HOT: 70 (100%).

iv) Significant difference between TH-T-ATG: P=0.09 (NS).

B) Follow-up: i) HT: a. 28 (5.71%) with EUT became HOT after 0.2(!)-8 years (av=2.77, S.D.=2.11). ii) 3 (0.61%) with EUT become HIT (all GBD). iii) 100% HOT remained HOT. iv) 15 (9.43) with HIT become EUT after 1.5–2 years and maintain at least 5 years. v) 4 (2.52%) with HIT become spontaneously HOT (two with GBD).

ii) T-ATG: only two HIT become EUT (33.3%). EUT&HOT remain the same.

iii) IM: all remained HOT, with one exception (man under amiodarone who return spontaneously to EUT after withdrawal amiodarone).

Conclusions: i) Thyroiditis with only hyperATG could be considered different from HT. ii) HT, T-ATG and IM presented differently as hormonal function. iii) H-TAG more than HT (but both) presented more as EUT than HOT. iv) Only 5% EUT-HT become HOT, during first 8 years. v) No EUT-HT after 8 years modified function. vi) Patients with HOT at diagnostic time, either HT, T-ATG or IM, remain HOT.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.