Endocrine Abstracts

A 51F domestic worker presented with classic clinical and biochemical features of acromegaly. This included a long history of arthralgia, increase in hand and foot size, paraesthesia requiring bilateral carpal tunnel release and coarsening of facial features. She was also newly diagnosed with hypertension and diabetes. On examination she demonstrated central adiposity, a prominent supra orbital ridge and nasal bridge, prognathism, interdental spacing, skin tags, and broad hands and feet. Pituitary MRI revealed a 16 mm X 23 mm lesion and visual fields were normal. Biochemistry showed IGF1 - 114.4 nmol/l(NR 6.5-35.5) GH 21.2 mg/l(with nadir of 18 on OGTT), decreasing to 4.2 on octreotide test dose and an otherwise normal pituitary profile. A diagnosis of acromegaly was made. On MDT consensus, pre-treatment with the somatostatin analogue Lanreotide 120 mg, 4weekly was given for 3 months to gain biochemical control and arrest tumour progression whilst the patient awaited trans-sphenoidal surgery (TSS). Surgery went well with no immediate postoperative concerns. On day 3, the patient developed transient DI followed by a protracted period of SIADH which proved challenging to manage. In this instance, there was limited response to multiple challenges with HTS (1.8% Hypertonic Saline) and the patient was successfully managed with repeat trials of Tolvaptan (See: Table 1). By day 16, SIADH had subsided with sodium levels returning to baseline. These findings are consistent with a biphasic response following pituitary surgery which is often challenging to manage. Histology was found consistent with a mixed somatotroph/lactotroph tumour with Ki67 1% and relevant outpatient follow-up was arranged.