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: Dental
Pinch purpura is diagnostic of – 
Select and explain. 
A. Systemic primary amyloidosis, B. Secondary systemic amyloidosis, C. Idiopathic thrombocytopenic purpura, D. Drug induced purpura
A: Systemic primary amyloidosis
Answer: A: Systemic primary amyloidosis 
Explanation: In primary systemic amyloidosis amyloid deposition occurs in the wall of the blood vessels, this leads to an increase in skin fragility. As a result, petechiae and purpura develop in clinically normal skin as well as in lesional skin following minor trauma. Therefore the skin lesions in case of primary systemic amyloidosis are called pinch purpura. These lesions are pink in colour and translucent.
Common locations are


Face (especially the periorbital and perioral regions)
Flexural areas.