Hypersomatotropism induced secondary polycythaemia leading to spontaneous pituitary apoplexy resulting in cure of acromegaly and remission of polycythaemia: 'The virtuous circle'.

A young man with subtle clinical features suggestive of hypersomatotropism presented with acute-onset severe headache. Relevant investigations confirmed polycythaemia and growth hormone (GH)-secreting pituitary macroadenoma with apoplexy. Secondary polycythaemia and myeloproliferative disorders were ruled out. At follow-up after 3 months, resolution of polycythaemia and acromegaly was observed, evident on normal haemoglobin levels, a normocellular marrow, and normal insulin-like growth factor-1 (IGF-1) with glucose-suppressed GH levels. Direct mitogenic properties of GH-IGF-1 axis on bone marrow progenitor cells may very rarely lead to erythroid hyperplasia and subsequent polycythaemia, reversible with successful therapy of acromegaly. In this case, polycythaemia secondary to hypersomatotropism likely resulted in pituitary apoplexy with subsequent remission of both acromegaly and resultant polycythaemia. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.