Tiêu đề 6. Leukocytoclastic vasculitis.pdf ✅

Leukocytoclastic vasculitis Causes: 1. Infections: Bacterial- Streptococcus, mycoplasma pneumonia, mycobacterial Viral- HIV, Hep C/B, influenza, CMV 2. Drugs- ASA, penicillin, sulfonamides, PTZs 3. IgA vasculitis- Henoch Schonlein purpura 4. ANCA-associated vasculitis: c-ANCA- Wegener’s granulomatosis p-ANCA- Churg-Strauss syndrome (Allergic granulomatosis with angiitis) & microscopic polyangiitis 5. Cryoglobulinemia (mixed Types II and III) (associated with Hep C/B, CTDs, infections, leukemia/lymphoma) 6. Urticarial vasculitis 7. Connective tissue disease/CTD associated- LE, Rheumatoid arthritis, DErmatomyositis, MCTD, sarcoidosis 8. Paraneoplastic manifestation- Hodgkin’s lymphoma, NHL, carcinoma 9. Special types- Granuloma faciale, Erythema elevatum diutinum Cryoglobulinemia- 1. Type 1- monoclonal Ig (Kappa or lambda): Associated with multiple myeloma, Waldenstrom’s macroglobulinemia, CLL, lymphoplasmacytic lymphoma Type 1 presents only with “thrombotic vasculopathy”- intravascular hyaline casts 2. Types 2 and 3 are “mixed cryoglobulinemias”- Type 2- monoclonal IgM + polyclonal IgG Type 3- polyclonal IgM + polyclonal IgG Both are “immune complex” mediated- present with both LCV+ thrombotic vasculopathy These can be a. Essential mixed- associated with Hep C/B b. Secondary mixed- Associated with- C- CTDs I-Infections (Infective endocarditis/infectious mononucleosis) L- Lymphomas/leukemias Meltzer’s triad in cryoglobulinemia- Purpura + arthralgia + weakness Urticarial Vasculitis Urticaria lasting >24 (48-72 hrs) Schnitzler’s syndrome- Urticarial vasculitis + IgM monoclonal gammopathy ), l(Hepatosplenomegaly, inc ESR, leukocytosis, fever, joint pains) Can be:
a. Normocomplementaemic b. Hypocomplementaemic- Associated with SLE Causes of urticarial vasculitis: 1. CTDs- LE, RA, Sjogren’s syndrome, MCTD 2. Infections- Hepatitis B/C, Infectious mononucleosis 3. Drugs- ACE inhibitors, CCBs (diltiazem), penicillin, thiazides, fluoxetine, sulfonamides 4. Monoclonal IgM gammopathy- Schnitzler’s syndrome 5. Leukemia (polycythemia/malignancies) Causes of thrombotic vasculopathy: 1. Cryoglobulinemia (especially type 1, but also types 2 and 3- associated with hep C/B, CTDS (ANA, anti-Ro/La), leukemia (CBC, Comprehensive metabolic panel) 2. Protein C/S deficiency- a. This is mostly congenital- mostly autosomal dominant- mutation of protein C gene on Chr 2 (PROC gene); mutation of Protein S gene (PROS1) gene on Chr 3. b. Acquired deficiency in- Chronic ulcerative colitis, anticoagulation/warfarin therapy, infections, Vit K deficiency Both protein C & S deficiencies predispose to- Warfarin necrosis & purpura fulminans 3. Prothrombin gene mutation/ Factor V Leiden mutation- causes rombocytope 4. Antiphospholipid antibody syndrome (Abs are- lupus anticoagulant, anticardiolipin abs, anti-B2 glycoprotein-1 Abs) Antiphospholipid Ab syndrome seen in pts with SLE, Rheumatpid arthritis, infections, drug-induced, malignancies, or can be idiopathic 5. Warfarin-induced skin necrosis- occurs in pts with: a. Long-time anticoagulant therapy due to secondary proteinC/S deficiency b. In pts with congenital (homozygous or heterozygous protein C/S deficiency) c. In pts with MTHFR gene mutation (Methylene tetrahydrofolate reductase gene) d. In pts with Factor V Leiden mutation 6. TTP (Thrombotic thrombocytopenic purpura)- clinical features of MAHA/thrombocytopenia/CNS symptoms/renal disease/fever) Antiplatelet drugs can clopidogrel & ticlopidine can cause TTP.
7. Sneddon’s syndrome 8. Bacterial endocarditis Causes of both thrombotic vasculopathy + vasculitis 1. Atrophie blanche/livedoid vasculopathy/livedo vasculitis 2. Septic vasculitis (Gram negative sepsis) 3. Ecthyma gangrenosum 4. DIC- disseminated intravascular coagulation- infections, tumors, snake bite, liver disease, obstetric conditions 5. Purpura fulminans- rare clinical manifestation of DIC- cutaneous hemorrhagic necrosis secondary to thrombosis of cutaneous microvasculature. Purpura fulminans can also occur in pts with protein C/S deficiency/Factor V Leiden mutation 6. Warfarin necrosis 7. Cocaine-levamisole induced skin necrosis- these patients have c-ANCAs 8. Antiphospholipid antibody syndrome Sneddon’s syndrome Neurocutaneous syndrome characterized by: 1. CNS ischemic events- cerebrovascular strokes 2. Ischemic ulcers with livedo reticularis- MC on legs MC in females- 3rd-4th decades This is an endothelialitis- “anti-endothelial Abs”- endothelial swelling- hence, thrombotic vasculopathy (ultimately neo- vascularization- new vessel proliferation around pre-existing hyalinized/occluded vessels) Sneddon’s syndrome can occur in patients with SLE & in anti- phospholipid Ab syndrome