Vasculitis Involving the Skin - Differential Diagnosis Framework Primary: 50% Cutaneous Vasculitis: Leukocytoclastic Vasculitis Secondary: CTD: SLE, RA related vasculitis, infections, drug eruptions, paraneoplastic Vasculitis Skin Findings: • Small Vessel: Petechiae, Palpable purpura, Hemorrhagic bullae, Ulceration, Urticaria • Medium Vessel: Subcutaneous nodules, Deep ulcers, Livedo reticularis, Livedo racemosa, Digital ulceration Small Vessel Vasculitis: • Immune Complex Vasculitis: - Ig A (HSP) - Anti-C1q (Urticarial/LCV) - Cryoglobulinemic Vasculitis • ANCA Associated: - Microscopic polyangiitis - EGPA - GPA Cutaneous Single Organ Vasculitis: • Leukocytoclastic vasculitis with IgG/IgM deposits • Nodular cutaneous vasculitis • Erythema elevatum diutinum Medium Vessel Vasculitis: • Cutaneous polyarteritis nodosa • Polyarteritis nodosa Large Vessel Vasculitis: • Temporal arteritis • Takayasu's arteritis Variable Vessel Vasculitis: • Behcet Disease • Cogan syndrome #Cutaneous #Vasculitis #skin #dermatology #rheumatology #differential #diagnosis
