Endocrine Abstracts

A 23-year-old female with severe resistant hypertension was referred to our Hospital. Her BP on arrival was 240/140 mmHg and she was 13 weeks pregnant. Labetalol had been prescribed previously (200 mg,TDS), with little success in controlling her symptoms. The patient reported headaches, migraines and flushing for several years, especially after eating, and worse during pregnancy. The patient had pre-eclampsia in her first pregnancy.

Prior to transfer, urinary normetanephrine was shown to be elevated (53.4 μmol/24 h, reference range <4.4). MRI of the abdomen revealed a 4.2×3.1×3.5 cm lesion on the left adrenal gland suggestive of a pheochromocytoma. The patient was not on any medications known to increase metanephrines.

On arrival at our Hospital, labetalol was stopped and phenoxybenzamine was prescribed (10 mg,TDS). Propranolol (10 mg) was administered when her HR exceeded 100 bpm lying down.

Plasma metanephrine analysis confirmed an increased normetanephrine (15070 pmol/L, reference range <1180) and an increased 3-methoxytyramine (343 pmol/L, reference range <75). Other than mildly raised white cells 15.6×10⁹/L (reference range 3.5–11.0), all other investigations were unremarkable. An USS of the neck showed no abnormalities.

Leading up to the surgery, phenoxybenzamine was increased from 10 mg TDS to 40 mg QDS; propranolol was increased to 30 mg QDS. After adequate α- and β-blockade, a left laparoscopic adrenalectomy was performed (patient was 15 weeks pregnant).

There were no intra-operative or post-operative complications; an abdominal USS performed post-surgery showed no complications to the foetus. The patient’s BP stabilised to 118/65 mmHg and she was discharged four days later.

At discharge plasma metanephrines had normalised. Two weeks post-discharge, blood samples were sent for evaluation of MEN, VHL, SDHB and SDHD genes.

Histological analysis revealed an encapsulated tumor showing infiltration of the capsule and possible minimal infiltration of peri-adrenal fat (PASS score 3). Immunohistochemistry revealed that cells expressed strong diffuse positivity for chromogranin and synaptophysin; thus confirming a PCC.