A 32yo man has been repeatedly admitted to hospital for what was described as anxiety or panic attacks and palpitations. On occasions he is found to be tremulous and hypertensive. A persistent weight loss is noted. What is the most probable dx?

The key is C. Pheochromocytoma. [There is no heat intolerance which goes against hyperthyroidism

and panic attack and hypertension favours the diagnosis of pheochromocytoma. Weight loss is seen in

phaeochromocytoma also. Catecholamine overproduction in pheochromocytoma affects basal

metabolism, resulting in weight loss despite normal food intake].