Endocrine Abstracts

A 35-year-old woman was seen at the medical obstetric antenatal clinic with gestational diabetes (GDM) and new-onset hypertension during the second trimester of her first pregnancy. She was well, with no prior medical history. Blood pressure of 120/80 had been recorded at her first antenatal visit. Throughout the pregnancy, GDM was managed successfully with diet alone: HbA1c always <5.8%. Methyldopa was initiated for persistent hypertension at 18 weeks gestation, and labetolol added at 28 weeks. Symptomatic postural hypotension required substitution of labetolol with nifedipine. Home BP monitoring revealed labile hypertension; she was admitted for further evaluation. Urinary catecholamine excess was found: noradrenaline 2850 nmol/24 hrs (NR 71–505), and normetadrenaline 8.8 micromol/24 hrs (NR<4.3). Urinary adrenaline and metadrenaline levels were within the normal limits. A phaeochromocytoma was suspected, therefore alpha-blockade with phenoxybenzamine commenced. On MRI, a 3×3×4 cm pelvic lesion was identified. Plans were made for elective caesarean delivery at 34 weeks, with simultaneous phaeochromocytoma removal. However, the development of proteinuria, rising AST levels and ongoing diastolic hypertension, led to an urgent caesarean section at 32 weeks. A live female infant was delivered, initially requiring NICU care. Pelvic exploration at the time of delivery did not identify a pelvic phaeochromocytoma. Hypertension persisted post-delivery, requiring intravenous nitrate and esmolol whilst on Critical Care, followed by oral alpha and beta-blockade. There was on-going catecholamine excess: urine noradrenaline 3681 nmol/24 hrs. MIBG scanning identified a focal area of increased uptake within the pelvis. Resection was scheduled for 12 weeks post delivery. At laparotomy, the pelvic tumour was successfully identified and removed. Despite prolonged alpha and beta blockade pre-operatively, during peri-operative tumour handling, systolic BP rose by 50 mmHg. Surgical resection was otherwise uneventful. Subsequent histology confirmed the complete excision of a benign phaeochromocytoma. The patient is now normotensive, off medication, with a healthy infant.