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 true about the features of erythromelalgia , EXCEPT: 
Select and explain. 
A. Unknown aetiology, B. Thrombocytosis is seen, C. Digital infarction is seen, D. Treatment is steroids
D: Treatment is steroids
Answer: D: Treatment is steroids 
Explanation: Erythromelalgia Syndrome of unknown etiology It is associated with thrombocytosis Manifested by erythema, warmth, and pain of the affected appendage and occasionally digital infarction. It usually respond to salicylates. Ref: Harrison, E-18,P-903