Petechiae, Purpura, Vasculitis

1.*You are consulted by general surgery about a new rash on this 16-year old girl with these lesions scattered over her legs. Over the phone your colleague described the rash as “many small dark red macules that don’t go away when I press on them.” What is the most appropriate morphologic term for this finding?
2.*You see the patient, a 16-year old girl with these lesions scattered over her legs and confirm she has petechiae and ecchymoses on her bilateral legs. They stop at her waist. She has mild abdominal pain, fatigue myalgias, and arthralgias. Her vital signs are T99.0 HR 94 RR 12 BP 106/82. WBC are 14.5, platelets are 165,000, and PT/INR is normal. What is the most likely cause of her purpura?

A 28-year-old woman presents with scattered red macules on her legs, ankles, and feet (see photo) that are neither painful nor itchy. What is the next best step in diagnosis?


A 7-year-old boy presents to the urgent care clinic with abdominal pain, joint aches, and a rash on his legs and feet (see photo). He does not have a history of frequent nosebleeds, easy bruising, or other episodes of abnormal bleeding. Based on the image and the patient’s history, what is the most likely diagnosis?

5.*This is a 38 year-old man with a history of Crohn’s disease, recently treated with azathioprine and prednisone. He was well until 3 days ago when he reported worsening abdominal pain. No recent sick contacts or travel. He presented to the ED with somnolence, fever, abdominal pain and a new rash. Vital signs were T102.1 HR 117 RR 14 BP 86/54. What is the most likely cause of his purpuric rash?
6.*This 69 year-old woman has noticed an increase in these marks (figure) on her forearms in the past month or two. She feels otherwise well and her review of systems is negative except for pain in her knees, which has chronic and due to osteoarthritis. She takes hydrochlorothizaode for hypertension, naproxen twice daily for osteoarthritis, a multivitamin, ginseng, garlic, and fish oil. What is the next step in the management of this patient?

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