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Published on: August 13, 2019
Endogenous estradiol may influence IGF-I levels in acromegalic women treated with pegvisomant
J Roemmler1, M Bidlingmaier, J Schopohl
1Endocrinology, Medizinische Klinik-Innenstadt, University of Munich, Ziemssenstr. 1, 80336, München, Germany. josefine.roemmler@med.uni-muenchen.de
Abstract:
We present the case of a 46-year-old woman with acromegaly currently being treated with the growth hormone (GH) receptor antagonist pegvisomant showing strongly fluctuating IGF-I levels. We prospectively measured estradiol, IGF-I, IGF-I binding protein, acid labile subunit, basal endogenous GH, binding protein and pegvisomant levels for 6 months every week. Estradiol levels showed a strongly negative correlation with IGF-I (r = -0.733, P < 0.001), and less so with ALS (r = -0.433, P < 0.05) and IGFBP3 (r = -0.590, P < 0.01). Estradiol was not significantly correlated with endogenous GH or pegvisomant levels. Likewise, IGF-I did not correlate with endogenous GH or pegvisomant levels. In our patient, endogenous estradiol levels have a significant influence on IGF-I levels. When female acromegalic patients on permanent pegvisomant treatment show fluctuating IGF-I levels, estradiol levels should be taken into consideration.
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