This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
All are clinical features of pheochromocytoma, except : 
Select and explain. 
A. Increased hematocrit, B. Ohostatic hypotension, C. Low coisol level, D. Impaired glucose tolerance
C: Low coisol level
Answer: C: Low coisol level 
Explanation: Answer is C (Low coisol level) Pheochromocytoma is not associated with low coisol levels. Pheochromocytoma is unique in presentation as it may present both with, Hypeension and hypotension. Hypeension occurs in paroxysms and is the most common manifestation - Hypotension occurs as `ohostatic hypotension' and it occurs as a consequence of diminished plasma volume and blunted sympathetic reflexes. Carbohydrate intolerance: Over half of patients have impaired carbohydrate tolerance due to suppression of insulin and stimulation of hepatic glucose output. Hematocrit: An elevated hematocrit may be secondary to diminished plasma volume.