Z005

 

Inpatient phaeo crisis in neurofibromatosis type1 (NF 1) "Triggers and management", role of magnesium sulphate in management of phaeo crisis

 

R Eltayeb, S Bitat, B Khoo, E Karra, S Ali, Royal Free Hospital

 

Background: Phaeochromocytomas are catecholamine-secreting tumours arising from chromaffin cells in the adrenal medulla. Phaeochromocytoma crisis (PCC) is an endocrine emergency associated with significant mortality estimated at ~15%. We describe herein a case where multidisciplinary team management was crucial in safely carrying the patient through a phaeo crisis and highlight precipitating factors and the role of magnesium in the treatment of phaeo crisis.

 

Case Presentation: A 63-year-old female with neurofibromatosis type 1 (NF-1), and previous renal artery stenosis bypass surgery, was admitted via A&E with increasingly frequent episodes of sweating, headache, dyspnoea and palpitations. Troponin was raised at 72 ng/l, progressively rising to 364 ng/l. CT pulmonary angiogram revealed a 6 cm left sided adrenal mass with cystic features. The possibility of phaeochromocytoma was raised and later confirmed by elevated metadrenaline at 5834pmol/L and normetadrenaline at 4198pmol/L). Doxazosin was commenced for alpha blockade with a view to introducing beta blockade at a later point. Subsequently she developed a narrow complex tachycardia treated with amiodarone, and chest pain treated with morphine and metoclopramide. She had a coronary angiogram which revealed unobstructed coronary arteries. Post angiogram she developed a broad complex tachycardia (recurrent VT) and uncontrolled hypertension at 254/112mmHg. She was admitted to ITU, and treated with magnesium sulphate infusion, phenoxybenzamine and verapamil. With magnesium sulphate, her condition stabilized, and BP controlled. She was discharged on phenoxybenzamine and verapamil. She underwent elective left adrenalectomy, nephrectomy, distal pancreatectomy and splenectomy. Histopathology revealed appearances of an adrenal medullary haemorrhagic pseudocyst, arising within a phaeochromocytoma. The lesion was completely excised with no involvement of the kidney or spleen and 0/3 lymph nodes, PASS score1.

 

Discussion: Phaeochromocytoma was considered early and blockade commenced.

 

1)     Nevertheless, patient had a crisis. Likely precipitants were:

a)     CTPA- IV, albeit non-iodinated contrast is considered safe.

b)     Possibly contributed by intra-arterial contrast during the

coronary angiogram.

c)     Metoclopramide use may have had a contributory role, which can worsen the crisis.

 

2)     Magnesium is useful in the management of severe refractory hypertensive emergencies. It acts by:

       Direct vasodilating action on arterioles.

       Inhibition of catecholamine release.

       Reduction of Alpha receptor sensitivity.