Endocrine Abstracts

We present a 45-year-old lady who initially presented with neurological symptoms and MRI was noted to show asymmetry of the pituitary gland. There were no endocrine symptoms. In 2011 she developed some visual symptoms (not typical of pituitary disease) and was referred to the ophthalmic department. MRI scan showed an 11 mm right-sided pituitary lesion and she was referred to the endocrine department. She gave a 2-year history of feeling increasingly unwell with back pain, sensory disturbance in her limbs, nausea and left-sided frontal headache. There were no symptoms or signs of pituitary dysfunction. Initial tests showed an elevated IGF1 38.9 nmol/l (13.0–35.0) but subsequent GH suppression test was normal (nadir GH 0.12 μg/l). Repeat IGF1 was normal (29.3 nmol/l). An insulin stress test (IST) with nadir glucose of 1.1 mmol/l revealed peak cortisol of 477 (NR >550) and peak GH of 1.28 μg/l (>6.6, 3.3-6.6 equivocal) demonstrating partial hypopituitarism. The patient began hydrocortisone replacement therapy. The patient underwent hypophysectomy May 2011. Histology showed a plurihormonal secreting tumour. Operation was difficult due to the tough nature of the adenoma and later MRI revealed residual adenoma. She subsequently had pituitary irradiation early 2012. The patient continued to feel unwell complaining of lack of concentration and tiredness. Adult GH deficiency assessment (AGHDA) was 23/25. Repeat IST in September 2012 demonstrated cortisol and GH deficiency (peak cortisol 396 nmol/l and peak GH 0.97 μg/l). She was therefore started on hydrocortisone and 0.1 mg GH treatment. However IGF1 level taken at time of IST was noted to be above the normal range (35.1 nmol/l). In conclusion we present a patient with conflicting results on GH status with repeatedly elevated IGF1 levels with GH deficiency on IST.