Immune complexes from vasculitis patients bind to endothelial Fc receptors independent of the allelic polymorphism of FcgammaRIIa. (1/75)

Cutaneous leukocytoclastic vasculitis is characterized by the deposition of circulating immune complexes, neutrophil extravasation, and vessel destruction, but mechanisms of circulating immune complexes capture within postcapillary venules are unknown. We demonstrate that circulating immune complexes from sera of vasculitis patients bind to cultured endothelium in an Fc gamma receptor IIa-dependent fashion. In lesional skin, endothelial cells bind immunoglobulin G2 > immunoglobulin G3 and immunoglobulin G4, but not immunoglobulin G1, even before obvious neutrophil transmigration and vessel damage. As the human Fc gamma receptor IIa proteins exist in two allotypes (one with a histidine at position 131, which binds immunoglobulin G1, 2, 3 and the other with an arginine at position 131, which binds immunoglobulin G1, and 3, but is unable to bind immunoglobulin G2), we expected an altered prevalence of histidine 131 forms in vasculitis patients. Sequence analysis, however, revealed an equal distribution of allotypes in patients and controls. In conclusion, circulating immune complex binding to endothelial Fc gamma receptor IIa is among the initial steps in the development of vasculitis. Although immunoglobulin G2 is the predominant subtype precipitated at endothelial surfaces, it is not required for fixing circulating immune complexes to endothelium, because patients homozygote for Fc gamma receptor IIa-arginine 131 equally develop leukocytoclastic vasculitis as those bearing the Fc gamma receptor IIa-histidine 131 allele. As immunoglobulin G1 is virtually absent in leukocytoclastic vasculitis lesions and immunoglobulin G4 does not bind to both Fc gamma receptor IIa alleles, these complexes, in addition to immunoglobulin G2, should contain immunoglobulin G3 in order to fix to vascular Fc gamma receptor IIa, at least in persons homozygous for Fc gamma receptor IIa-arginine 131. KEYWORDS: CD32/immunoglobulin G subtypes/leukocytoclastic vasculitis/microvessels.  (+info)

Cholesterol embolism in a patient with inflammatory abdominal aortic aneurysm. (2/75)

A 66-year-old man whose renal function had progressively deteriorated had an elevated blood pressure and also was found to have an inflammatory abdominal aortic aneurysm (AAA). Blood examination revealed that he had eosinophilia. Livedo reticularis of the toes developed, and a skin biopsy specimen showed embolization of atheromatous plaques in the arterioles of the subcutaneous tissue. Progressive enlargement of inflammatory AAA may have dislodged the atheromatous plaques, resulting in cholesterol embolism.  (+info)

Validation of the Sapporo criteria for antiphospholipid syndrome. (3/75)

OBJECTIVE: To test the Sapporo criteria for the classification of the antiphospholipid syndrome (APS). METHODS: We classified 243 consecutive patients who had clinical diagnoses of primary APS (n = 49), secondary APS (n = 26), systemic lupus erythematosus (SLE) without clinical APS (n = 131), and lupus-like disease without clinical APS (n = 37). RESULTS: Sensitivity, specificity, positive predictive value, and negative predictive value were 0.71, 0.98, 0.95, and 0.88, respectively. False-negative findings were the result of patients being classified on the basis of minor criteria that were not included in the Sapporo criteria, such as livedo reticularis, thrombocytopenia, low-titer IgG or IgM anticardiolipin antibody, IgA anticardiolipin antibody, and anti-beta2-glycoprotein I antibody. Some patients with false-negative results were true seronegative cases. CONCLUSION: The Sapporo criteria for APS compare favorably with the American College of Rheumatology criteria for SLE and are usable for clinical studies.  (+info)

Popliteal vein entrapment: a benign venographic feature or a pathologic entity? (4/75)

PURPOSE: Asymptomatic morphologic popliteal vein entrapment is frequently found in the healthy population (27%). In our institution, popliteal vein compression on plantar flexion was observed in 42% of all ascending venograms. Some authorities consider the lesion benign, without pathologic significance. This study examines the pathophysiologic importance in select patients, describes treatment with surgery, and suggests a diagnostic tool. METHOD: Thirty severely symptomatic patients with venographic evidence of popliteal entrapment were selected to have popliteal vein release after a process of elimination (ie, other causes of chronic venous insufficiency [CVI] were ruled out by means of comprehensive hemodynamic and morphologic studies). In the last nine limbs, popliteal vein pressure was also measured by means of the introduction of a 2F transducer tip catheter. Patients were clinically and hemodynamically assessed before and after surgery, and anatomical anomalies encountered during surgery were recorded. RESULTS: Popliteal vein release was performed without mortality or serious morbidity. Anomalies of the medial head of the gastrocnemius muscle caused entrapment in 60% of the patients; anatomic course venous anomalies were infrequent (7% of the patients). Significant relief of pain and swelling occurred in the patients who had surgery. Stasis ulceration/dermatitis resolved in 82% of patients. Popliteal venous pressures had normalized in the six patients who were studied postoperatively. CONCLUSION: Popliteal vein entrapment should be included in the differential diagnosis of CVI in patients in whom other, more common etiologies have been excluded on the basis of comprehensive investigations. Popliteal vein compression can be demonstrated venographically in a large proportion of patients with CVI, but the lesion is likely pathological only in a small fraction of these patients. A technique for popliteal venous pressure measurement is described; it shows promise as a test for functional assessment of entrapment. Immediate results of popliteal vein release surgery are encouraging; long-term follow-up is necessary to judge the efficacy of surgical lysis of entrapment in symptomatic patients who fail to improve with conservative treatment measures.  (+info)

Pneumomediastinum in dermatomyositis: association with cutaneous vasculopathy. (5/75)

OBJECTIVES: To study the pathogenesis of pneumomediastinum in polymyositis/dermatomyositis (PM/DM). PATIENTS AND METHODS: The clinical records of 48 patients with PM/DM were reviewed, focusing mainly on the presence of pneumomediastinum and cutaneous vasculopathy, and the chest radiographic changes. A patient with pneumomediastinum with a characteristic change in his bronchus is described in detail. Case reports of pneumomediastinum in PM/DM in English publications are reviewed. RESULTS: Among the 48 patients with PM/DM, pneumomediastinum was observed as a complication in four patients with DM and none of the patients with PM. Three of the four patients with pneumomediastinum, but only six of the 44 patients without this complication, had associated cutaneous vasculopathy. There was a significant association of pneumomediastinum with cutaneous vasculopathy (p = 0.02) and younger age (p = 0.04), but not with the prevalence of lung disease. A 30 year old man (patient 1) with DM, who had interstitial pneumonitis and skin ulceration due to vasculopathy, developed pneumomediastinum. Fibreoptic bronchoscopy showed white plaques on the bronchial mucosa, which were confirmed by microscopic examination as representing subepithelial necrosis. A literature review showed 13 cases of DM but no patient with PM with pneumomediastinum. CONCLUSIONS: In patient 1, bronchial necrosis due to vasculopathy was strongly suspected as being responsible for the pneumomediastinum. The results suggest that pneumomediastinum was associated not with interstitial pneumonitis but with the complication of vasculopathy appearing as skin lesions in DM.  (+info)

Susac's syndrome: beneficial effects of corticosteroid therapy in a Japanese case. (6/75)

Susac's syndrome is a rare disorder characterized by the triad of microangiopathy of the brain and retina with hearing loss. More than 50 affected individuals have been reported worldwide, all Caucasians. We herein identify the first Japanese patient with Susac's syndrome. A 36-year-old man developed recurrent subacute encephalopathy, bi- a lateral sensorineural hearing loss, and retinal arteriolar occlusions, caused by microangiopathy from a year previously. T2-weighted MRI showed multiple high-signal lesions ti predominantly in the periventricular white matter. During the exacerbated phase both high-dose intravenous methyl-prednisolone and oral prednisone therapy produced beneficial effects. He showed definite remission within 2 years from the disease onset.  (+info)

Newer skin signs of systemic disease. (7/75)

The skin is a well-known reflection of internal disease states. It provides the astute clinician with clues that lead to the diagnosis of systemic illness. While skin disease is rarely life-threatening, serious morbidity and mortality may be avoided by early recognition of subtle cutaneous signs signaling internal problems. The recent literature was reviewed to glean new findings that either added new associations to older syndromes or described completely new diseases. While entire books are written regarding the "Skin Signs of Internal Disease", this article focuses only on the newest of such findings.  (+info)

Improving ischaemic skin revascularisation by nerve growth factor in a child with crush syndrome. (8/75)

Nerve growth factor (NGF) is the first described neurotrophin that stimulates the growth and differentiation of nerve cells and promotes skin and peripheral tissue regeneration. Recent studies suggest that NGF influences endothelial cell proliferation and angiogenic activity. In view of these proposed regenerative effects, we evaluated the efficacy of subcutaneous administration of highly purified murine NGF in a child with severe crush syndrome of the lower left limb. NGF 10 micro g was administered subcutaneously every eight hours for seven days to the extensive ischaemic skin lesion of the calcaneal area. After treatment we observed gradual improvement of the ischaemic area; no side effects were noted. The child was discharged in good clinical condition to await a limited calcaneal escharotomy.  (+info)