Thrombo-embolic disease is an increasingly recognised complication of several vasculitides. A common observation is that thrombo-embolic complications coincide with periods of increased vasculitis disease activity, but the mechanism through which this happens is still unknown. Thrombo-embolic disease has been recognised for decades as a significant contributor to the morbidity and mortality of Behçet's disease, and the role of anticoagulation in its management is being minimised in favour of immunosuppression, although evidence from randomised controlled trials is lacking. Ancillary data from a randomised clinical trial and retrospective observational studies have confirmed an association between venous thrombo-embolic disease and vasculitides associated with anti-neutrophil cytoplasmic antibodies (ANCAs). An increased cardiovascular risk is now also recognised for vasculitides associated with ANCAs. Thrombosis plays a prominent role in the pathogenesis of thromboangiitis obliterans (Buerger's disease). The association of thrombosis with other vasculitides such as giant-cell arteritis and levamisole-induced vasculopathy is under investigation.

Idiopathic systemic vasculitis represents a group of clinical entities having non-specific etiology with the common characteristic of acute or chronic inflammatory compromise of the small and large vessels walls, associated with fibrinoid necrosis.To describe the most common inflammatory vascular diseases in a long historical cohort of patients from San Juan de Dios Hospital located in Bogota, Colombia using two different systems and a clinical histopathological correlation format, and to make a comparison between them.We reviewed all previously ascertained cases of vasculitis confirmed by biopsy processed between 1953 and 1990, and systematically collected data on all new cases of vasculitis from 1991 to 1997 at the Hospital San Juan de Dios (Bogota-Colombia). The cases were classified in accordance with the Chapel Hill Consensus criteria, and the system proposed by J.T. Lie.Of 165,556 biopsy tissue specimens obtained during this period from our hospital, 0.18% had vasculitis, perivasculitis or vasculopathy. These included 304 histopathological biopsies from 292 patients. Cutaneous leukocytoclastic vasculitis (64 histological specimens) was the most frequently encountered type of "primary" vasculitis followed by thromboangiitis obliterans (38 specimens), and polyarteritis nodosa (24 specimens). Vasculitis associated with connective tissue diseases (33 specimens) and infection (20 specimens) were the main forms of secondary vasculitis, a category that was omitted from the Chapel Hill consensus report. We found that 65.8% of our histopathological diagnoses could not be classified according to the Chapel Hill classification, and 35.2% could not be classified according to the classification of Lie. Only 8.9% of cases remained unclassified by our system after clinical and histological correlation.Current vasculitis classification schemes are designed for classification, rather that diagnosis of disease and do not adequately address some common forms of inflammatory vascular diseases, including those of infectious etiology and unusual etiology seen in clinical practice. Based on our clinical experience, we suggest a classification outline which practitioners can use which emphasizes correlation of the clinical picture to the histopathology findings for diagnosis and therapy, which may promote better clinical practice and standardization for clinical trials.

Modern ultrasound (US) equipment allows rheumatologists to directly visualize hand and finger arteries. How does US aid in diagnosis of Raynaud's phenomenon (RP)?Color Doppler US of the proper and common palmar digital, radial, and ulnar arteries and the superficial palmar arch of both hands was performed in 135 consecutive patients who presented with suspected RP.US was pathologic in 63% of patients with secondary RP, in 6% with primary RP, and in none with pseudo-RP (p < 0.0001). We found 3 types of vascular pathology: Type 1 showed narrowing or chronic occlusion of some proper digital arteries; Type 2 was characterized by the same finding in all proper digital arteries; and Type 3 involved acute occlusions. Type 1 was found in 3 of 53 patients with primary RP and in 19 patients with secondary RP including 5 of 9 patients with anti-centromere positive systemic sclerosis (SSc); Type 2 occurred in 16 patients with SSc, MCTD, and dermatomyositis; and Type 3 was found in 8 patients with antiphospholipid antibody syndrome, thromboangiitis obliterans, vibration trauma, or vasculitis. The ulnar arteries were more commonly affected than the radial arteries. The 2nd radial, 3rd radial, 4th ulnar, and 5th ulnar proper palmar digital arteries were most commonly involved.Aiding in differentiating primary versus secondary RP, severe versus less severe disease, and acute versus chronic vascular occlusion, digital artery US depicts the same anatomical structures as angiography, but it is cheaper, faster, and noninvasive.

Vasculitides, including Wegener's granulomatosis, Takayasu's arteritis, giant cell arteritis, Kawasaki disease, Behçet disease, thromboangiitis obliterans and erythema elevatum diutinum, are inflammatory diseases of blood vessel wall characterized by myointimal proliferation, fibrosis and thrombus formation leading to stenosis or occlusion of the vascular lumen, and finally to tissue ischemia. In these diseases the hypoxic environment subsequent to stenosis or occlusion of the vascular lumen is a potent signal for the generation of new blood vessels. Angiogenesis may be a compensatory response to ischemia and to the increased metabolic activity and may be also a further inflammatory stimulus because endothelial cells of newly-formed vessels express adhesion molecules and produce colony-stimulating factors and chemokines for leukocytes.

Since Kussmaul and Maier described the index case of vasculitis in 1866, the field has seen many changes. What was considered for decades to be only a single disorder is now known to consist of at least 15 to 20 distinct conditions. Important strides have been made in unraveling the pathophysiology of some individual forms of vasculitis, but many mysteries remain. Over time, numerous myths and occasional pearls have arisen from the care of patients with these disorders. This collection of pearls and myths gathers lessons about the status of clinical care of vasculitis patients in the year 2008.

Vasculitides are defined by inflammation of blood vessel walls leading to vascular stenosis or occlusion, with various degrees of fibrinoid necrosis of the media and inflammatory infiltration, mainly neutrophilic and sometimes granulomatous. Various classifications of the vasculitides have been proposed. The classifications used most today are the 1990 American College of Rheumatology classification and the Chapel Hill nomenclature, published in 1994 . Only the latter distinguished between polyarteritis nodosa and microscopic polyangiitis and stressed the importance of antineutrophil cytoplasm autoantibodies (ANCA). In practice, primary systemic vasculitides are classified according to their clinical presentations, their precise histological features, and the size of the predominantly affected vessels. Some small-vessel vasculitides are associated with the presence of ANCA: 90% of patients with systemic Wegener's granulomatosis (mainly ANCA with cytoplasm labeling on indirect immunofluorescence and proteinase 3 specificity), 80% of the subjects with microscopic polyangiitis (mostly pANCA with myeloperoxidase specificity), and more than one third of those with Churg-Strauss syndrome (mostly pANCA).

Thromboangiitis obliterans (Buerger's disease)--a type of vasculitis in young, mostly male subjects--remains strangely linked to smoking, which determines its occurrence, progression and prognosis by currently unknown mechanisms. It affects the small and medium-sized arteries and veins of the limbs. Despite the usual absence of systemic signs and symptoms, initially intermittent arthritis, even if not observed in all cases, confer on this disease the status of a systemic vasculitis. Diagnosis requires the elimination of many other diseases. The severity of the disease lies in the need for amputation in more than a quarter of all patients. Complete cessation of smoking remains the cornerstone of therapy. Local care is the second essential element of treatment. Prostacycline analogues can be used to help the patient through critical ischaemia. Blockade with antagonists of cannabinoid or endothelin receptors and the use of gene- or cell-based therapy to induce therapeutic angiogenesis have opened up new possibilities for treatment.

Thromboangiitis obliterans (TAO) is an inflammatory, nonocclusive, and nonatherosclerotic vascular disease. It commonly affects arteries, veins, and surrounding neural elements and is directly related to smoking. Although distal vessels of lower and upper extremities are the most commonly involved, other vessels such as intestinal arteries can be rarely affected. The authors describe a 41-year-old white male smoker who presented with abdominal pain for 3 months and developed an acute bowel ischemia. He underwent urgent surgery, and segmental enterectomy was performed. Histopathologic findings were suggestive of TAO, showing typical involvement of small-sized veins and arteries with intact internal elastic lamina, preserved media, a local nonspecific inflammatory reaction, with new and older arterial and venous thromboses associated. Although mesenteric arteries are seldom injured by TAO, this diagnosis must be considered when the usual causes of intestinal ischemia are ruled out. In this case, even without any other clinical symptoms of TAO, this rare diagnosis could be made.