This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune skin disorders, Subject name: Dental
[{'content': '"Pinch" purpura is diagnostic of - \nSelect and explain. \nA. Systemic primary amyloidosis, B. Secondary systemic amyloidosis, C. Idiopathic thrombocytopenic purpura, D. Drug induced purpura', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Pinch Purpura: A Cutaneous. Manifestation of Systemic. Amyloidosis Amyloid purpura is a condition marked by bleeding under the skin (purpura) in some individuals with amyloidosis. Its cause is unknown, but coagulation defects caused by amyloid are thought to contribute presentation: Amyloid purpura usually occurs above the nipple-line and is found in the webbing of the neck and in the face and eyelids Ref Harrison20th edition pg 1245', 'role': 'assistant'}]