You are in: eMedicine Specialties > Dermatology > DISEASES OF THE VESSELS Wegener GranulomatosisArticle Last Updated: May 26, 2006AUTHOR AND EDITOR INFORMATIONAuthor: Christen M Mowad, MD, Assistant Professor, Department of Dermatology, Geisinger Medical Center Christen M Mowad is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, and Phi Beta Kappa Coauthor(s): David Hensley, MD, Mullanax Dermatology Associates, Arlington Memorial Hospital Editors: Abby S Van Voorhees, MD, Assistant Professor, Director of Psoriasis Services and Phototherapy Units, Department of Dermatology, University of Pennsylvania School of Medicine, Hospital of the University of Pennsylvania; David F Butler, MD, Professor of Dermatology, Texas A&M University College of Medicine; Director, Division of Dermatology, Scott and White Clinic; Director Dermatology Residency Training Program, Scott and White Clinic; Jeffrey P Callen, MD, Professor of Medicine, Chief, Division of Dermatology, University of Louisville School of Medicine; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; William D James, MD, Paul R Gross Professor of Dermatology, University of Pennsylvania School of Medicine; Vice-Chair, Program Director, Department of Dermatology, University of Pennsylvania Health System Author and Editor Disclosure Synonyms and related keywords: Wegener's granulomatosis, WG INTRODUCTIONBackgroundWegener granulomatosis (WG) is a rare multisystem disease characterized by necrotizing granulomatous inflammation of the upper and lower respiratory tract and kidneys and by necrotizing vasculitis affecting small- and medium-sized vessels. In 1931, Klinger first classified WG as a variant of polyarteritis nodosa. In 1936, Wegener described the disease as a distinct entity with specific clinical and histopathologic criteria. PathophysiologyThe etiology of WG remains unknown. Current research has focused on the relevant mechanisms of inflammation, particularly the effect of inflammatory mediators and immune effector cells on the endothelium. Evidence suggests that WG is an autoimmune inflammatory process, with antineutrophil cytoplasmic antibodies (c-ANCA) directed at neutrophil proteinase 3 (PR-3) involved in the pathophysiology of the disease. Neutrophils and endothelial cells are involved in early lesions as both targets and promotors of inflammation. c-ANCA may be responsible for events that lead to the activation of neutrophils, which, in turn, selectively target the endothelium. Endothelial cell damage and activation of neutrophils produce inflammatory mediators, leading to recruitment of monocytes and T cells and increased endothelial damage. FrequencyUnited StatesWG is a rare disease with an as yet undetermined incidence. InternationalThe incidence in the United Kingdom is estimated at 8.5 cases per million persons per year. Mortality/Morbidity
RaceWG is mostly reported in whites; it rarely occurs in blacks. Black race may be a predictor of treatment resistance in ANCA-positive vasculitides. Sex
AgeOnset may occur at any age; patients typically present at age 35-55 years. CLINICALHistoryNecrotizing granulomas may be found in any organ system. The upper respiratory tract (especially the nose and sinuses) is the most commonly affected site. The typical presentation includes upper airway symptoms, such as sinusitis or nasal discharge. The lungs are affected in 85% of patients. Disease severity is usually related to renal involvement, which occurs in 75% of patients. Cutaneous manifestations occur in 35-50% of patients, and they may be the presenting sign of disease in 13% of patients. Patients exhibiting cutaneous manifestations more commonly have renal and articular disease. Ulcers and vesicles are associated with more severe and extensive disease.
PhysicalPhysical findings are described below.
CausesThe etiology is unknown. More recent studies suggest that c-ANCA may be directly related to the pathogenesis. Other studies favor a delayed-type hypersensitivity reaction to unknown antigens.
DIFFERENTIALSAcute Febrile Neutrophilic Dermatosis Churg-Strauss Syndrome (Allergic Granulomatosis) Henoch-Schönlein Purpura (Anaphylactoid Purpura) Leishmaniasis Pyoderma Gangrenosum Relapsing Polychondritis Rhinoscleroma Syphilis Temporal (Giant Cell) Arteritis Yaws
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Drug Name | Cyclophosphamide (Cytoxan, Neosar) |
|---|---|
| Description | Chemically related to nitrogen mustards. As an alkylating agent, the mechanism of action of the active metabolites may involve cross-linking of DNA, which may interfere with growth of normal and neoplastic cells. |
| Adult Dose | Daily oral dose: 2 mg/kg/d PO qd IV pulse therapy: 0.5 g/m2 IV every month for 6 mo; adjust subsequent doses to maintain WBC of 3-5 X 103/µL |
| Pediatric Dose | Administer as in adults |
| Contraindications | Documented hypersensitivity; severely depressed bone marrow function |
| Interactions | Allopurinol may increase risk of bleeding or infection and enhance myelosuppressive effects; may potentiate doxorubicin-induced cardiotoxicity; may reduce digoxin serum levels and antimicrobial effects of quinolones; chloramphenicol may increase half-life, while decreasing metabolite concentrations; may increase effect of anticoagulants; coadministration with high doses of phenobarbital may increase rate of metabolism and leukopenic activity; thiazide diuretics may prolong CYC-induced leukopenia and neuromuscular blockade by inhibiting cholinesterase activity |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Caution in leukopenia, thrombocytopenia, previous therapy with other cytotoxic agents or radiation, or impaired renal or hepatic function; associated with numerous potentially serious adverse events, including risk of malignancy, sterility, hemorrhagic cystitis, cardiac toxicity, and serious infection secondary to immune suppression; other common adverse events include nausea, vomiting, and alopecia (anagen effluvium); monitor closely for neutropenia and microscopic hematuria; patients should maintain a substantial water intake and void frequently during treatment |
| Drug Name | Methotrexate (Folex, Rheumatrex) |
|---|---|
| Description | Unknown mechanism of action in treatment of inflammatory reactions; may affect immune function. Ameliorates symptoms of inflammation (eg, pain, swelling, stiffness). Antimetabolite that inhibits DNA synthesis and cell reproduction in malignant cells; may suppress immune system. Satisfactory response seen 3-6 wk following administration. Adjust dose gradually to attain satisfactory response. |
| Adult Dose | 0.3 mg/kg/wk PO/IM; not to exceed 20 mg |
| Pediatric Dose | 5-15 mg/m2/wk PO/IM single dose or 3 divided doses given 12 h apart |
| Contraindications | Documented hypersensitivity; alcoholism; hepatic insufficiency; documented immunodeficiency syndromes; preexisting blood dyscrasias (eg, bone marrow hypoplasia, leukopenia, thrombocytopenia, significant anemia) |
| Interactions | Oral aminoglycosides may decrease absorption and blood levels of concurrent oral MTX; charcoal lowers levels; coadministration with etretinate may increase hepatotoxicity; folic acid or its derivatives contained in some vitamins may decrease response to MTX; coadministration with NSAIDs may be fatal; indomethacin and phenylbutazone can increase plasma levels; may decrease phenytoin serum levels; probenecid, salicylates, procarbazine, and sulfonamides, including TMP-SMZ, may increase effects and toxicity; may increase plasma levels of thiopurines |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Monitor CBC counts monthly and liver and renal function q1-3mo during therapy (monitor more frequently during initial dosing, dose adjustments, or when risk of elevated levels, eg, dehydration); has toxic effects on hematologic, renal, GI, pulmonary, and neurologic systems; discontinue if significant drop in blood counts; aspirin, NSAIDs, or low-dose steroids may be concomitantly administered (possibility of increased toxicity with NSAIDs, including salicylates, has not been tested) |
Have anti-inflammatory properties and cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli.
| Drug Name | Prednisone (Orasone, Meticorten, Deltasone, Sterapred) |
|---|---|
| Description | This widely used synthetic glucocorticoid exerts metabolic effects on multiple organ systems and is commonly used in inflammatory diseases for its potent anti-inflammatory properties. High-dose glucocorticoids may induce more rapid control at the beginning of treatment; however, steroid-sparing drugs (eg, CYC) are needed to control more aggressive cases. |
| Adult Dose | 1 mg/kg/d PO |
| Pediatric Dose | Administer as in adults |
| Contraindications | Documented hypersensitivity; systemic fungal infection |
| Interactions | Phenytoin, phenobarbital, ephedrine, and rifampin enhance metabolic clearance of corticosteroids; hypokalemia may develop in patients concomitantly treated with potassium-wasting diuretics; corticosteroids may affect anticoagulant effects of coumarin |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Adrenal insufficiency may develop after prolonged therapy with corticosteroids; symptoms of corticosteroid withdrawal include fever, malaise, myalgia, and arthralgia; corticosteroid therapy should be slowly tapered; corticosteroids may induce or exacerbate psychiatric derangements, ranging from insomnia and euphoria to frank psychosis; impairs wound healing; caution in patients with uncontrolled systemic infections, ocular herpes simplex, renal insufficiency, hypertension, peptic ulcer disease, or myasthenia gravis |
Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in this clinical setting.
| Drug Name | Trimethoprim and sulfamethoxazole (Bactrim, Bactrim DS, Septra, Septra DS) |
|---|---|
| Description | Inhibits bacterial growth by inhibiting synthesis of dihydrofolic acid. |
| Adult Dose | 160 mg TMP/800 mg SMZ PO q12h for 10-14 d |
| Pediatric Dose | <2 months: Do not administer > 2 months: 15-20 mg/kg/d, based on TMP, PO tid/qid for 14 d |
| Contraindications | Documented hypersensitivity; megaloblastic anemia due to folate deficiency |
| Interactions | May increase PT when used with warfarin (perform coagulation tests and adjust dose accordingly); coadministration with dapsone may increase blood levels of both drugs; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly patients; phenytoin levels may increase with coadministration; may potentiate effects of MTX in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase zidovudine levels |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Discontinue at first appearance of skin rash or sign of adverse reaction; obtain CBC counts frequently; discontinue therapy if significant hematologic changes occur; goiter, diuresis, and hypoglycemia may occur with sulfonamides; prolonged IV infusions or high doses may cause bone marrow depression (if signs occur, give 5-15 mg/d leucovorin); caution in folate deficiency (eg, persons with long-term alcoholism, elderly persons, those receiving anticonvulsant therapy, or those with malabsorption syndrome); hemolysis may occur in persons with G-6-PD deficiency; AIDS patients may not tolerate or respond to TMP-SMZ; caution in renal or hepatic impairment (perform urinalyses and renal function tests during therapy); give fluids to prevent crystalluria and stone formation |
Most commonly used therapy for this condition is oral potassium iodide.
| Drug Name | Potassium iodide (SSKI, Pima) |
|---|---|
| Description | Works via potassium concentration in granulomas, which releases heparin and inhibits delayed-type hypersensitivity response. |
| Adult Dose | 300-500 mg PO (6-10 gtt) tid |
| Pediatric Dose | Infants: 150-250 mg (3-6 gtt) PO tid Children: Administer as in adults |
| Contraindications | Documented hypersensitivity; pulmonary edema; bronchitis; tuberculosis; hyperkalemia |
| Interactions | Increases lithium toxicity by producing additive hypothyroid effects |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Prolonged use may result in hypothyroidism; caution in renal failure and GI obstruction |
TNF-alpha may play a role in ANCA-associated activation of neutrophils and monocytes and/or in neutrophil adherence to endothelial cells. Of note, results of the Wegener's Granulomatosis Etanercept Trial (WGET) have shown no effectiveness of etanercept (Enbrel) in the maintenance of disease remission. A high rate of complications was noted in the etanercept group, including a higher rate of solid cancer development.
| Drug Name | Infliximab (Remicade) |
|---|---|
| Description | Infusable chimeric IgG1 monoclonal anti-TNF-alpha antibody approved for the treatment of Crohn disease, rheumatoid arthritis, and psoriatic arthritis. Limited data have shown remission induction in cases refractory to standard CYC and corticosteroid combination therapy with the addition of infliximab. May allow reduction in corticosteroid dosages once remission occurs. |
| Adult Dose | 3-5 mg/kg IV at weeks 0, 2, and 6, with maintenance infusions given q4-6wk after induction; may be increased up to 10 mg/kg Used at dosages of 3-5 mg/kg for adjunctive treatment of WG, with infusions q4wk following induction; anecdotal evidence indicates dose-response phenomena, with higher dosages leading to more remissions |
| Pediatric Dose | Administer as in adults |
| Contraindications | Patients with moderate-to-severe heart failure may have worsening of heart failure; relatively contraindicated in uncontrolled infections; tuberculosis or PPD-positive patients should be treated for tuberculosis prior to infliximab initiation |
| Interactions | None reported |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Black box warning for serious infections, including tuberculosis, histoplasmosis, listeriosis, pneumocystosis, and coccidioidomycosis Antibody production against infliximab may lead to rare cases of lupuslike syndrome; incidence of lymphoma and other malignancies is 3-5 times higher rheumatoid arthritis patients treated; rare cases of hepatotoxicity may occur |
| Drug Name | Azathioprine (Imuran, Azasan) |
|---|---|
| Description | Has been shown in trials to be an effective substitution for CYC after induction of remission with standard CYC/corticosteroid therapy in systemic vasculitides, including WG. Relapse rates, however, are higher in WG compared with microscopic polyangiitis. |
| Adult Dose | 2 mg/kg/d with corticosteroid therapy |
| Pediatric Dose | Administer as in adults |
| Contraindications | Documented hypersensitivity; low thiopurine methyltransferase activity; relatively contraindicated in patients who have received high-dose CYC therapy due to risk of malignancy |
| Interactions | Use with TMP/SMX or ACE inhibitors may induce severe leukopenia |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | May cause GI hypersensitivity; thioguanine methyltransferase levels should be determined prior to therapy initiation; potential mutagen, with increased risk of neoplasia |
| Media file 1: Large ulceration of the pharynx covered with a dense necrotic membrane. | |
![]() | View Full Size Image | Media type: Photo |
| Media file 2: Necrotic, purpuric, and blistering plaque on the wrist. | |
![]() | View Full Size Image | Media type: Photo |
| Media file 3: Several necrotic, purpuric, and blistering papules and plaques on the hands. | |
![]() | View Full Size Image | Media type: Photo |
Wegener Granulomatosis excerpt
Article Last Updated: May 26, 2006