Endocrine Abstracts

A 16-year-old male, previously well, presented with 3 days history of non-specific body ache and headache. His blood pressure was 194/127mmHg, heart rate 115 beats/minute but had normal examination findings otherwise. His BP was high throughout his admission and his BMI was 20 kg/m2. Drug history was unremarkable. We noted he had transaminitis with predominantly elevated alkaline phosphatase (ALP). His ALP was 397U/l(40-105 U/l), Alanine transaminase (ALT) 124U/l(0-50 U/l), Aspartate transaminase (AST) 140U/l(1-50 U/l) and total bilirubin 21umol/l (<20 umol/l) Hepatitis screening was normal and abdominal ultrasound revealed right suprarenal mass with normal liver and biliary findings. CT Neck, Thorax and Abdomen showed a suprarenal mass with peripheral enhancement and central hypodense cystic component, measuring 5.5 x 4.6 x 5.7 cm with a plain attenuation of +22 HU, absolute washout of 23% and relative washout of 9%. Low dose dexamethasone suppression test showed suppressed cortisol and 24 Hour urine metanephrines revealed elevated levels of Normetanephrine: 56.50 umol/day (0.50 - 2.49 umol/day) and 3-Methoxytyramine: 4.20 umol/day (0.10 - 1.79 umol/day. The diagnosis of pheochromocytoma was made and he was started on alpha then subsequently beta blockade with high salt diet. Interestingly we noted his cholestasis resolved in 4 weeks after starting on antihypertensives. Surgery was delayed for 2 months due to socioeconomic constraints. Post surgery, histopathological examination revealed findings consistent with pheochromocytoma with no evidence of necrosis. It is reported this is likely due to effects of excessive interleukin-6 (IL-6). Catecholamines can increase IL-6 production which is shown to cause intrahepatic cholestasis. Besides, it is also shown alpha adrenergic receptors have significant influence in the increased expression and secretion of IL-6. Hence alpha blockade may reduce IL6 secretion. However, reports vary on when IL-6 reduces in patients with pheochromocytoma. Some case reports have shown that it reduces with alpha and beta adrenergic blockade and hence the improvement in liver injury. Others have shown IL-6 level normalised only after adrenalectomy. This difference could be due to severity of adrenal tumour necrosis as it is postulated the bigger the necrosis, the higher the IL-6 production. This may possibly explain why our patient’s liver function test normalised after commencing antihypertensives as there was no evidence of tumour necrosis on either CT scan or HPE examination. Hence early pharmacological treatment and definitive surgery should be instituted as soon as possible once the diagnosis is confirmed.