Management of a phaeochromocytoma in pregnancy
Barbara McGowan1, Catherine Williamson1,2, Karim Meeran1, Anita Banerjee1,2, Lee Min1,3, Bill Fleming1,3, Duncan Bassett1 & Tricia Tan1
A 30-year-old lady was transferred to our hospital at 37 weeks of pregnancy. Hypertension was noted at 24 weeks of gestation and managed with methyldopa and labetalol. Despite treatment, BP was labile with a systolic of 90220 and diastolic of 50129 mmHg. She reported occasional palpitations but not chest pain or shortness of breath. The patient had a history of migrainous headaches but not hypertension prior to pregnancy. Her brother had previously had an operation for a benign abdominal lesion. Abdominal ultrasound demonstrated a 5.2×5.7 cm mass superio-posteriorly to the right kidney. Twenty-four hour urine noradrenaline excretion was grossly elevated at 4470 nmol/24 h (non-pregnant normal range 0560 nmol/24 h). Adrenaline and dopamine levels were normal. A diagnosis of a right-sided phaeochromocytoma was made. On admission, labetalol and methyldopa were stopped. She was hydrated with IV fluids and treated with phenoxybenzamine 0.5 mg/kg over 24 h for 3 consecutive days. She developed a tachycardia and was commenced on propranolol 40 mg tds. An elective Caesarean section at 37½ weeks performed under continued IV alpha and beta blockade resulted in the delivery of a healthy and normotensive baby girl. Intravenous phenoxybenzamine was discontinued 2 days after delivery and oral phenoxybenzamine commenced. She was discharged home 5 days later on phenoxybenzamine 10 mg tds and propanolol 40 mg tds. Post-operatively she remained asymptomatic with lying and standing BPs of 130/70 and 115/80 respectively. An MIBG scan 3 weeks later showed avid uptake consistent with a right-sided phaechromocytoma. Calcium and calcitonin were normal. Adrenalectomy was performed 5 weeks post-partum. She remains normotensive after withdrawal of antihypertensive medication, and catecholamine excretion levels remained normal. Genetic testing revealed that both she and her brother carry a germline mutation in SDH-B.