Somatotropin adenoma and resistance to thyroid hormone.
Resistance to thyroid hormone (RTH) is a rare disease characterized by non-suppressed TSH in spite of high free thyroid hormone levels. Up to date, in the literature, there are more than 600 RTH cases, but co-incidental hypophyseal adenoma was reported in only 1 case. In the literature, despite reported cases with thyrotropinoma accompanying RTH, we could not find a case with somatotropinoma accompanying RTH. Here, we report a 34-yr-old male patient, who was admitted to the hospital with complaints of dyspnea, chest pain, and palpitation in 2003. His alpha- subunit value was normal and the alpha-subunit/TSH molar ratio was <1. His response to TRH stimulation test was normal. His TSH level was suppressed in the T3 suppression test. Hypophyseal magnetic resonance imaging showed a 6-mm hypophyseal microadenoma. Levels of all anterior hypophyseal hormones, including GH and IGF-I, were normal. Oral glucose tolerance test (OGTT)-GH suppression test was normal. The patient was followed with the diagnosis of RTH and incidental hypophyseal adenoma. After 3 yr, because of high levels of IGF-I: 901 ng/ml (68-324), the OGTT-GH suppression test was reported and no suppression was detected. Thus, the patient was referred to surgery with the pre-diagnosis of RTH and acromegaly. Immunohistochemistry was showed as strong GH staining with low Ki 67 index while TSH and other anterior hypophyseal hormones stainings were negative. Post-operative thyroid hormones were still high.
Berker
D
D
Endocrinology and Metabolism Department, Ankara Numune Education and Research Hospital, Ankara, Turkey. dberker6@yahoo.com
Aydin
Y
Y
Tutuncu
Y A
YA
Isik
S
S
Delibasi
T
T
Berker
M
M
Guler
S
S
Kamel
N
N
D000328:Adult; D003940:Diagnostic Techniques, Endocrine; D049912:Growth Hormone-Secreting Pituitary Adenoma / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D033162:Incidental Findings; D008297:Male; D010911:Pituitary Neoplasms / Q000150:complications* / Q000175:diagnosis; D018382:Thyroid Hormone Resistance Syndrome / Q000150:complications*