Petechiae/Purpura - Diagnostic Algorithm. Pathophysiology: 1) Represent the passage of erythrocytes from the intravascular to extravascular compartment 2) May be the result of disruption of vascular integrity (trauma, infection, vasculitis) or disorders of primary or secondary hemostasis. Palpable: 1) If lesions are palpable, this may suggest a more prominent underlying inflammatory process such as vasculiitis. 2) When cutaneous manifestations are identified, other small vessels may be affected (commonly renal and pulmonary #Diagnosis #Dermatology #Rash #Petechiae #Purpura #Palpable #Algorithm #Differential #Ddxof
