Rapid Changes of Thyroid Function in a Young Woman with Autoimmune Thyroid Disease

Effects of block-replace regimen in patients with autoimmune hypothyroidism converted to Graves' disease

PURPOSE

We present two cases of autoimmune hypothyroidism converted to Graves' disease (GD) and their medical management.

METHODS

We tested thyroid function and thyroid antibodies and performed an ophthalmologic examination and neck ultrasound in two patients with autoimmune hypothyroidism converted to GD during a follow-up of several years.

CASE REPORTS

The first case is a 33 year-old woman with hypothyroidism due to Hashimoto's thyroiditis (HT). She developed signs and symptoms of hyperthyroidism after 7 years of treatment with the same dose of levothyroxine (LT4). Even when LT4 therapy was discontinued, she remained thyrotoxic, with mild Graves' ophthalmopathy (GO) and very high thyroid-stimulating hormone receptor antibodies (TRAb > 40 IU/L, reference range: <1.75 IU/L). Antithyroid medication was started on a titration regimen, without achievement of euthyroidism. She was switched to a block and replace regimen, using 20 mg of methimazole (MMI) and 75 mcg of LT4 daily, with normalization of thyroid hormones and improvement of GO without steroids. The second case is a 57 year-old man with a 2-year positive medical history of HT and 6 months of LT4 treatment. He developed hyperthyroidism and moderate-severe GO. Despite stopping LT4 and initiating antithyroid medication in a titration regimen, he did not achieve euthyroidism and had active GO. Pulse glucocorticoid therapy and switching to a block-replace regimen was required to achieve euthyroidism and reduce ocular proptosis and diplopia.

CONCLUSION

Spontaneous autoimmune conversion of hypothyroidism to hyperthyroidism can occur at any time: it is important to promptly identify these cases so as to manage them effectively.

Minor hyperthyroidism with normal levels of thyroid-stimulating hormone receptor antibodies: a case report

The present report describes for the first time a case of diffuse hyperthyroidism in a 30-year-old female patient who had normal levels of thyroid-stimulating hormone receptor antibodies (TSHR-Ab), slightly elevated plasma levels of thyroid hormones, and slightly increased thyroid blood flow. Seven years before, after severe stress, she had Graves' disease with elevated plasma levels of TSHR-Ab. The patient's recent medical history included mental stress and autonomic dysfunction. This report describes a mild form of hyperthyroidism in terms of elevated plasma levels of thyroid hormones and Doppler ultrasonography data; this condition was first defined as 'minor hyperthyroidism'. The examination data suggest a probable secondary role of the immune system and primary role of the autonomic nervous system in the pathogenesis of Graves' disease.

Case Report: Multisystem Autoimmune and Overlapping GAD65-Antibody-Associated Neurological Disorders With Beneficial Effect of Epilepsy Surgery and Rituximab Treatment

Glutamic acid decarboxylase (GAD) antibodies are associated with disabling conditions such as stiff person syndrome, temporal lobe epilepsy (TLE), limbic encephalitis, cerebellar ataxia (CA), and ocular movement disorders, which are usually chronic and difficult to treat. GAD-related TLE has poor response to anti-seizure medications and immune therapies, and epilepsy surgery is rarely successful. We report on a 47-year-old female with history of migraine, autoimmune thyroid disease, ankylosing spondylitis, and drug-resistant TLE. A video electroencephalography recorded frequent seizures with temporo-insular semiology, correlating to left temporal epileptiform activity and left mesiotemporal hyperintensity on magnetic resonance imaging. GAD autoimmunity was confirmed by very high GAD antibody titers in serum and cerebrospinal fluid. Steroids, immunoglobulins, and cyclophosphamide had no effect, and selective left amygdalectomy was performed based on very restricted hypermetabolism on positron-emission tomography. After transient seizure freedom, significant epilepsy improvement was observed in spite of memory decline. Transient worsening was noted 1 year later during diabetes mellitus manifestation and 5 years later during presentation of progressive CA, which stabilized on rituximab treatment. We believe this case illustrates the diversity and the frequent overlap of GAD-associated disorders, the need of early and aggressive immunotherapy in severe patients, as well as the possible benefit from epilepsy surgery in some GAD-TLE.

Ultra-processed food consumption and risk of subclinical thyroid dysfunction：A prospective cohort study

Background: Prospective cohort studies linking Ultra-processed foods (UPF) and subclinical thyroid dysfunction (SCTD) are limited, especially in Chinese adults. Objective: We designed a large-scale cohort study to examine whether UPF...