Unexpected conversion from hypothyroidism to an euthyroid state due to Graves' disease in a patient with an ectopic thyroid

Pendulum swings from hypo- to hyperthyroidism: thyrotoxicosis after severe hypothyroidism following neck irradiation in a patient with a history of Hodgkin's lymphoma

Background

A change in a thyrometabolic state from severe hypothyroidism to thyrotoxicosis is very uncommon, but possible in some circumstances.

Case presentation

A 27-year old female presented with clinical and biochemical thyrotoxicosis with a previous history chemo- and radiotherapy (including the neck region) for a Hodgkin’s lymphoma (at the age of 18). At the age of 20 this was followed by severe hypothyrodism [TSH > 100 μIU/mL (reference range: 0.27–4.2)]. She was stated on L-thyroxine, but the dose was later reduced and subsequently discontinued. She had significantly elevated titres of both anti-thyroid peroxidase antibodies and anti-TSH-receptor antibodies throughout the course of disease. Thyroid scintigraphy revealed a normal and homogenous iodine uptake.

Conclusions

We suspect that a gradual switch from thyroid-blocking to thyroid-stimulating antibodies resulted in development of an overt thyrotoxicosis, possibly with a contributory effect of neck irradiation on her autoimmune status.

MiR-346 regulates CD4⁺CXCR5⁺ T cells in the pathogenesis of Graves' disease

Follicular helper T (Tfh) cells are increasingly recognized as participants in various autoimmune diseases, including Graves' disease. Although many transcription factors and cytokines are known to regulate Tfh cells, the role of noncoding RNA in Tfh cells development and function is poorly understood. Twenty-three patients with GD, eleven patients with remitting GD, and twenty-four healthy controls were enrolled in the current study. The interaction of miRNA and target gene was predicted through software analysis and then validated by luciferase assay and Western blot. The levels of miR-346 in circulating CD4(+) T cells and plasma were measured by qRT-PCR. The correlation of miR-346 levels with the percentages of CD4(+)CXCR5(+)T cells and autoantibody levels were also analyzed. Up-regulation of Bcl-6 and down-regulation of miR-346 in GD patients were observed, and miR-346 could inhibit Bcl-6 at both transcriptional and translational levels. Overexpression of miR-346 led to attenuating CD4(+)CXCR5(+) T cells. The abnormal expression of miR-346 restored in GD patients after treatment. A negative correlation between levels of miR-346 and percentages of CD4(+)CXCR5(+) T cells was confirmed in GD patients. Additionally, negative correlations between the levels of miR-346 in circulating CD4(+) T cells and serum concentrations of TR-Ab, TG-Ab, and TPO-Ab were also revealed in GD patients. MiR-346 regulates CD4(+)CXCR5(+) T cells by targeting Bcl-6, a positive regulator of Tfh cells, and might play an important role in the pathogenesis of Graves' disease.

Prevalence, Phenotype, and Psychosocial Well-Being in Euthyroid/Hypothyroid Thyroid-Associated Orbitopathy

BACKGROUND

At the onset of thyroid-associated orbitopathy (TAO), most patients are hyperthyroid, while scarce data are available on euthyroid/hypothyroid TAO. The aim of this study was to assess the prevalence, phenotype, and psychosocial burden of patients with initially euthyroid/hypothyroid TAO.

METHODS

The medical records of 461 consecutive and unselected patients with TAO followed at a specialized joint thyroid-eye clinic were analyzed within this retrospective cross-sectional study. Main outcome measures were the prevalence of initially eu- or hypothyroid TAO as well as ophthalmic signs and symptoms, disease-specific quality of life (QoL), work impairment, and rate of psychotherapy in initially eu-/hypothyroid versus hyperthyroid TAO.

RESULTS

The prevalences of eu-/hypothyroid and hyperthyroid TAO were 4.3% (n=20; [confidence interval, CI, 2.6-6.3]) and 95.7% (n=441; [9.37-9.74]), respectively. In 12 patients (2.6% [CI 1.3-4.3]), Hashimoto's thyroiditis was present and in 8 (1.7% [CI 0.7-3.0]) no thyroid disease was noted at the time of inclusion. One (0.05%) patient with eu-/hypothyroid TAO and 172 (39%) with hyperthyroid TAO had clinically active TAO (p=0.001). In eu-/hypothyroid versus hyperthyroid patients, 14 (70%) versus 135 (30.6%) had a mild TAO, 6 (30%) versus 183 (64.2%) a moderate-to-severe TAO, and 0 versus 23 (5.4%) had a sight-threatening TAO (p<0.001). TAO was asymmetric in 4 (20%) eu-/hypothyroid and in 27 (6.1%) hyperthyroid patients (p=0.038). Only 5.3% versus 30.2% and 10.5% versus 44.1% of patients with eu-/hypothyroid and hyperthyroid TAO, respectively, were on sick leave (p=0.003) or work disabled (p=0.018). QoL was less impaired in eu-/hypothyroid versus hyperthyroid TAO (median visual functioning and appearance scores: 100 versus 75; p<0.001 and 81.25 versus 75; p=0.315). Of patients with eu-/hypothyroid and hyperthyroid TAO, 15% and 20.2% had psychotherapy respectively (p=0.409). Eu-/hypothyroid TAO was positively (odds ratio 7.05, p=0.060) and negatively (odds ratio: 0.09, p=0.026) associated with a unilateral involvement and thyrotropin-receptor autoantibodies respectively.

CONCLUSIONS

Compared with hyperthyroid TAO, QoL and working ability are less impaired in eu-/hypothyroid TAO with an often asymmetric and less severe clinical phenotype.