EUROPEAN ACADEMY OF DERMATOLOGY AND VENEREOLOGY Information Leaflet for Patients

CUTANEOUS IMMUNE COMPLEX VASCULITIS, SKIN-LIMITED CUTANEOUS IGA OR IGG/IGM VASCULITIS (Formerly called: Allergic/Hypersensitivity Vasculitis)

The aim of this leaflet This leaflet is designed to help you understand more about cutaneous immune complex vasculitis or skin -limited IgA or IgG/IgM vasculitis (formerly called allergic/hypersensitivity vasculitis). It tells you what this condition is, what causes it, and what can be done for treatment. CUTANEOUS What are immunoglobulins (IgA, IgG and IgM)? Immunoglobulins or antibodies are proteins made by the immune system to fight antigens, IMMUNE COMPLEX such as bacteria, viruses, and toxins. The body makes 5 different types of immunoglobulins VASCULITIS, to combat different antigens. Immunoglobulin A (IgA): is found in high concentrations in the mucous membranes, SKIN-LIMITED particularly those lining the respiratory passages and gastrointestinal tract, as well as in CUTANEOUS saliva and tears. Immunoglobulin G (IgG): the most abundant type of antibody, is found in all body fluids and IGA OR IGG/IGM protects against bacterial and viral infections. VASCULITIS Immunoglobulin M (IgM), which is found mainly in the blood and lymph fluid, is the first antibody to be made by the body to fight a new infection.

What is allergic vasculitis? In half of cases, a trigger of cutaneous immune complex vasculitis can be identified, Cutaneous immune complex vasculitis, the most common of which include recent usually manifesting as skin -limited IgA or acute infections (eg. upper respiratory tract IgG/IgM vasculitis (formerly called:¨Allergic/ infections, viral hepatitis and HIV infection) hypersensitivity vasculitis) belongs to the or certain medications: antibiotics are cutaneous small-vessel vasculitides, and is a the most common drugs to cause disorder characterized by the inflammation cutaneous immune complex vasculitis, of some small blood vessels located mainly particularly beta-lactams. nonsteroidal anti- in the skin, called post-capillary venules. inflammatory drugs and diuretics. However, Other small vessels located in the internal almost all drugs and drug additives are organs (like the kidneys (most frequently), potential causes. bowels, or joints) may be affected as well. The disease is then referred to as systemic Other causes or forms (variants) of cutaneous IgA vasculitits or Hennoch Schönlein purpura, immune complex vasculitis vasculitis are: which on the skin has exactly the same • connective tissue vascular diseases symptoms as the skin-limited forms. (such as small vessel immune complex vasculitis in systemic lupus erythematosus What causes allergic vasculitis? or Sjogren’s syndrome, whereas vasculitis Cutaneous immune complex vasculitis in rheumatoid arthritis often also affects is thought to be mediated by immune medium vessels) complex deposition. In this form of • malignancies /cancer (mostly hematologic vasculitis, circulating antigens in the ones, and in rare cases, solid organ body induce antibody formation. These neoplasms) antibodies bind to the circulating antigen • inflammatory bowel diseases and create immune complexes, which then deposit within vessels, activating • chronic active hepatitis complement and inducing inflammatory • foods or food additives may also cause mediators. Inflammatory mediators, cutaneous immune complex vasculitis adhesion molecules, and local factors may affect the endothelial cells and play a role in In the other half of cases, no cause can the manifestations of this disease. be identified, so the cutaneous immune complex vasculitis could then be called “idiopathic.”

EADV INFORMATION LEAFLET FOR PATIENTS I VASCULITIS Who is affected and what are How is it diagnosed? the characteristics of allergic The diagnosis of cutaneous immune complex vasculitis? or IgA vasculitis is made by a clinician by Cutaneous immune complex vasculitis (as recognizing the characteristic skin lesion, by well as systemic IgA vasculitis or Hennoch obtaining a physical examination, a careful Schönlein purpura) may occur at any age medical history from the patient (as well as (both children and adults), and in both an extensive screening for possible triggers men and women of all races, but it is such as infections, inflammatory disorders, slightly more common in women. It is medication, etc.). It is very important to characterised by three types of skin lesions: perform repeated urine anaylsis in order to palpable purpura (violet-coloured, elevated detect or exclude renal involvement (as in skin lesions [papules] that do not change systemic IgA vasculitis). colour when pressed [“non-blanching”]), The diagnosis is confirmed by a skin biopsy, retiform purpura (violet-coloured, net-like or which involves the removal of a small skin stellate erythemas that also do not change sample under local anaesthesia, which will colour when pressed [“non-blanching”]), be further examined under a microscope by located primarily on the lower legs (due to a pathologist. inflammation of small vessels), hemorrhagic blisters sometimes developing into necrotic How does it evolve? ulcers. These lesions are mainly located on areas that are prone to stasis like the ankles Almost 90% of patients experience a and shins, due to destruction of vessels with spontaneous resolution of the skin lesions ensuing leakage of blood into the tissue within only a few weeks, while 10% will have (explaining the purpuric lesions). a chronic or recurrent disease at variable intervals (months to years). What are the signs and Therefore, in patients with identified triggers symptoms of allergic vasculitis? (like drugs or treatable infections), the disease will disappear after eliminating the The skin lesions are asymptomatic in most trigger, and it may not recur. Still, there are cases, but sometimes they can be associated other cases with triggers like inflammatory with an itching/burning sensation or diseases, chronic infections, malignancies, local pain. Apart from the palpable and or “idiopathic cases,” in which the evolution retiform purpura, and ulcers, signs and and prognosis depends on the underlying symptoms affecting beyond the skin can condition and with an increased risk of also occur, depending on the extent of the recurrence. Additionally, when internal inflammatory reaction and involvement of organs are also affected, the prognosis is internal organs, such as flu-like symptoms, worse. abdominal pain, diarrhoea, bloody stool, joint and muscle pain.

EADV INFORMATION LEAFLET FOR PATIENTS I VASCULITIS CUTANEOUS How is it treated? How can I prevent the IMMUNE COMPLEX First of all, your clinician needs to check development of cutaneous any possible trigger and treat it (e.g. immune complex vasculitis VASCULITIS, treatment of a certain infectious cause or (skin-limited or systemic IgA SKIN-LIMITED discontinuing a certain medication). Aside vasculitis (Hennoch Schönlein from this, the treatment approach varies, purpura)? taking into account the severity and extent CUTANEOUS You should seek medical advice by seeing of the disease. IGA OR IGG/IGM your general physician at the first cutaneous In most patients, the lesions heal signs which may look like the ones described VASCULITIS spontaneously after withdrawal of the above with cutaneous immune complex trigger, but in some cases supportive vasculitis, in order to minimize, if possible, or pharmacological treatment can be the evolution and extent of a possible used. In the latter case, non-steroidal systemic disease. anti-inflammatory and antihistamine medications are used first. If there are What can I do if I am diagnosed hemorrhagic blisters, oral glucokorticoids with it? are recommended to prevent formation of ulcers (steroids rather provide symptomatic There are not many significant things you relief, but do not treat the cause), The second can do to influence the natural course choice includes colchicine or dapsone. Only of cutaneous immune complex vasculitis rarely, if at all immunosuppressive agents (as part of skin-limited or systemic IgA (like methotrexate) and biological drugs vasculitis). Avoidance of certain drugs (like infliximab or rituximab) are required. that in the past were involved in the All treatments should be performed under development of vasculitis may help to avoid the guidance of experienced, specialised another episode. n clinicians.

While every effort has been made to ensure that the information given in this leaflet is accurate, not every treatment will be suitable or effective for every person. Your own clinician will be able to advise in greater detail.

PRODUCED BY THE EADV VASCULITIS AND VASCULOPATHY TASK FORCE

EUROPEAN ACADEMY OF DERMATOLOGY AND VENEREOLOGY Publication date: 2019 Copyright © EADV