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Published on: January 17, 2018
[Pituitary resistance to thyroid hormone--a case report]
W Zieleniewski1, J Jurczyńska, J Kunert-Radek
1Department of Clinical Endocrinology, Medical University of Lodz, Poland. wz1964@wp.pl
Endokrynologia Polska
|July 4, 2006
Summary
This study details a rare case of pituitary resistance to thyroid hormone, a condition causing hyperthyroidism with elevated thyroid hormones and normal/high TSH. Bromocriptine treatment successfully restored thyroid hormone balance and reduced goiter size.
Area of Science:
- Endocrinology
- Molecular Endocrinology
Background:
- Pituitary resistance to thyroid hormone (PRTH) is a rare endocrine disorder.
- Characterized by elevated thyroid hormones (T3, T4) with inappropriately normal or elevated thyroid-stimulating hormone (TSH).
Observation:
- A 24-year-old woman presented with mild thyrotoxicosis and diffuse goiter.
- Laboratory results showed elevated free T3 (fT3) and free T4 (fT4) with a slightly elevated TSH.
- Imaging and hormonal tests excluded pituitary adenoma and confirmed normal TSH response to TRH administration.
Findings:
- Diagnosis of pituitary resistance to thyroid hormone syndrome was established.
- Treatment with bromocriptine (10 mg/day) led to euthyroidism within 2 months.
- Thyroid volume significantly diminished over the subsequent months.
Implications:
- Bromocriptine is an effective therapeutic option for managing pituitary resistance to thyroid hormone.
- This case highlights the importance of considering PRTH in patients with apparent hyperthyroidism and normal/elevated TSH.
- Successful treatment can lead to normalization of thyroid function and reduction of goiter.
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