Endocrine Abstracts

Introduction: We report a patient who presented with presumed intestinal obstruction, and was subsequently diagnosed with an adrenal phaeochromocytoma associated with venous thromboembolism. We review the literature and discuss underlying mechanisms for these uncommon manifestations.

Case presentation: A 56-year-old man with background untreated hypertension presented with abdominal distension, vomiting, breathlessness and haemoptysis. Heart rate (HR) was 126/min and blood pressure (BP) 159/95 mmHg at presentation. CT scan of the abdomen revealed dilatation of a long segment of small bowel, with a transition point at the distal jejunum. A heterogeneous 4.6×4.5×4.9 cm left adrenal mass with associated renal vein thrombosis and left lower lobe segmental pulmonary embolism was noted. Emergent exploratory laparotomy and bowel decompression followed. Intra-operatively, no mechanical cause for intestinal obstruction was identified. Post-operatively, he had uncontrolled hypertension and tachycardia, with BP up to 200/120 mmHg, and HR up to 120–140/min. Urinary catecholamines were ten times above the normal range, confirming the diagnosis of left adrenal phaeochromocytoma. Ga-68 DOTA-TATE PET-CT did not reveal any evidence of metastatic disease. Anticoagulation was started and patient was optimised medically before laparoscopic left adrenalectomy was performed.

Discussion: These uncommon initial manifestations can be explained by a state of catecholamine excess. Ileus occurs due to suppression of gastrointestinal peristalsis. Catecholamines exert a direct effect on primary and secondary haemostasis, and adrenergic infusions have been shown in vivo to increase fVIII activity, vWF antigen, tPA activity, and platelet activation and aggregation. Both arterial and venous thromboses have been reported in the literature. Overall, these are relatively uncommon and also likely under-reported phenomena in patients with phaeochromocytoma. A greater awareness of these associations will enable clinicians to avoid missing a potentially catastrophic diagnosis.