54M h/o IVDU, HCV untreated who p/w leg pain, worsening ulcers in s/o skin popping, found to have vasculopathy/vasculitis likely levamisole related vs cryoglobulinemic.
Seeing a patient who uses IV drugs? Make sure to ask about these ROS points:
- The last time you injected, was there something different?
- Have you had any complications/past infxns related to use?
- What is your filter type/syringe source?
- What is the route of administration of drugs?
- Have you ever been clean?
- Do you use by yourself or other people?
- Have access to naloxone?
- Do you have any hardware in you?
Leg ulcer ddx:
- bacterial, viral, fungal, spirochete, protozoal
- Common: Venous, arterial, neuropathic
- Physical/Bites: thermal burns, cold injury, radiation, trauma, spiders
- Vasculopathies: livedoid, buerger’s dz (Thromboangiitis obliterans)
- Vasculitis of small/medium vessels…see compliment diagram below!
- Small vessel: idiopathic, infxn, drugs, mixed cryoglobulinemia, SLE, RA, malignancies, GPA, eosinophilic granulmatosis with polyangitis (Churg-Strauss), microscopic polyangiitis, Henoch-Schonlein Purpura, levamisole induced vasculitis
- Medium vessel: GPA, Churg-Strauss, cutaneous and systemic polyarteritis nodosa
- Hypercoagulable states: Factor V Leiden, APLS, Protein C/S deficiency
- Vaso-occlusive disorders: calciphylasix, cholesterol emboli, type I cryoglobulinemia, cryofibrinogenemia, oxalosis
- Pyoderma gangrenosum
- Panniculitis: alpha-1 antitrypsin deficiency, pancreatic fat necrosis, erythema induratum
- Malignancy: SCC, BCC, cutaneous T/B cell lymphoma, KS
- Drugs: Hydroxyurea, warfarin, heparin
- Systemic Sclerosis
- Hematologic dz: hemoglobinopathies, thrombocytosis
Brouet classification of cyroglobulinemia based on immunological analysis:
- Type 1: Presence of isolated monoclonal Ig (typically IgG or IgM), usually Waldenstrom’s macroglobulinemia or multiple myeloma, generally malignancy related
- Type 2: Mixture of polyclonal Ig in association with a monoclonal Ig such as IgM or IgA, w/ RF activity. Usually due to persistent viral infxns, particular HCV and HIV
- Type 3: Mixed version consisting of polyclonal Ig without monoclonal component. These are generally secondary to autoimmune disorders (CTD), but can be associated with infxn’s
How to interpret complement levels in vasculitis? Here is an algorithm from rheumatology based on when biopsies confirm the dx with the finding of Leukocytoclastic Vasculitis on path.