Pathology of a new Toxic Syndrome caused by ingestion of adulterated oil in Spain

Summary The Toxic Syndrome (TS) caused by ingestion of adulterated rapeseed oil in Spain is a new disease of multisystemic character whose aetiology and pathogenesis remains unknown. The most prominent pathological feature is a peculiar non-necrotizing vasculitis, that affects mainly the intima and involves vessels of every type and size in practically every organ. The TS begins with an acute clinical picture with pleuropneumopathy, fever, headaches, exanthems and eosinophilia. In these early clinical phases the main pathological findings were observed in the lungs and consisted of intense pulmonary interstitial oedema with scanty inflammatory mononuclear infiltrates. Ultrastructural study revealed hydropic degeneration of pneumocytes types I and II with desquamation of type I. The patients in this phase died of respiratory failure, later deaths were due to thromboembolic complications. Later still the patients developped a neuromuscular syndrome, sclerodermiform skin lesions and severe weight loss and died predominantly of infectious complications and respiratory failure. The anatomopathological picture in the peripheral nerves was that of inflammatory neuropathy with a lymphocytic perineuritis that led to perineural fibrosis with secondary axonal degeneration. The muscle presented an interstitial inflammatory myopathy at first followed by a neurogenic muscular atrophy. The skin lesions in the late phases consisted in dermal or dermal and subdermal fibrosclerosis, with vasculitis of the small arteries in the lower dermis. The salivary glands and pancreas showed vasculitis and interstitial inflammation which progressed to interstitial fibrosis and parenchymal atrophy.     

Inflammatory muscle involvement in systemic vasculitis: A systematic review

Vasculitis are severe systemic autoimmune diseases which may involve different organs and systems. Conversely, muscles do not represent an organ commonly involved by systemic vasculitis and myositis is not include among any classification or diagnostic criterion of vasculitis.In this regard, we aimed to review the literature in order to report all the available evidence concerning the inflammatory involvement of muscle in patients affected by systemic vasculitis.We collected a total of 108 papers, for a sum of 395 patients affected by muscle vasculitis. Most of them suffered from medium and small vessels vasculitis (mainly polyarteritis nodosa and ANCA-associated vasculitis) or from vasculitis secondary to rheumatoid arthritis. Conversely, muscle involvement in case of large vessel vasculitis occurred seldom, while only few papers reported such occurrence in Kawasaki or Behçet's disease.Histological findings may differ, but the most common ones displayed a necrotizing vasculitis of perimysium vessels, while granulomatous vasculitis was assessed only in case of ANCA-associated vasculitis patients.Creatine kinase were usually within normal range, seldom elevated, while imaging findings were generally undistinguishable from the ones found in idiopathic inflammatory myopathies: magnetic resonance imaging displays signal hyperintensity in T2 and STIR scans, while few data exist for positron emission tomography.The presentation of the disease may be fearsome and severe, sometimes life-threatening, but an overall good response to conventional immunosuppressants and/or glucocorticoids has been reported.     

Fc receptors gone wrong: A comprehensive review of their roles in autoimmune and inflammatory diseases

Systemic autoimmune and inflammatory diseases have a complex and only partially known pathophysiology with various abnormalities involving all the components of the immune system. Among these components, antibodies, and especially autoantibodies are key elements contributing to autoimmunity. The interaction of antibody fragment crystallisable (Fc) and several distinct receptors, namely Fc receptors (FcRs), have gained much attention during the recent years, with possible major therapeutic perspectives for the future. The aim of this review is to comprehensively describe the known roles for FcRs (activating and inhibitory FcγRs, neonatal FcR [FcRn], FcαRI, FcεRs, Ro52/tripartite motif containing 21 [Ro52/TRIM21], FcδR, and the novel Fc receptor-like [FcRL] family) in systemic autoimmune and inflammatory disorders, namely rheumatoid arthritis, Sjögren's syndrome, systemic lupus erythematosus, systemic sclerosis, idiopathic inflammatory myopathies, mixed connective tissue disease, Crohn's disease, ulcerative colitis, immunoglobulin (Ig) A vasculitis, Behçet's disease, Kawasaki disease, IgG4-related disease, immune thrombocytopenia, autoimmune hemolytic anemia, antiphospholipid syndrome and heparin-induced thrombocytopenia.     

Association of COL11A2 polymorphism with susceptibility to Kawasaki disease and development of coronary artery lesions

Kawasaki disease (KD) is a pediatric systemic vasculitis of unknown etiology wherein genetic influence is suspected. Gene clusters within the HLA region at chromosome 6p21.3 have been linked to KD and other autoimmune disorders. As collagen is a strong autoantigen inducing chronic inflammation in patients with vasculitis, this study tests a hypothesis that single-nucleotide polymorphism (SNP) of a collagen gene, COL11A2, located in this HLA region may affect susceptibility to Kawasaki disease and its arterial sequels. SNP sites rs2294478 (at promoter) and rs2076311 (at intron 19) were genome-typed on 93 KD patients and 680 healthy subjects. Genotypic and allelic frequencies analyses found A allele at rs2076311 as a risk allele for KD. Clinical association study showed protective potential of C/C genotype at rs2294478 and A/A at rs2076311 for developing coronary artery lesions (CALs) in patients. In addition, C-A haplotype of COL11A2 gene associates with KD development and can serve as a genetic marker to differentiate KD patients lacking CALs from those with such lesions. Our findings suggest the involvement of genetic variations of COL11A2 in Kawasaki disease and CAL formation.     

HMGB1 in vascular diseases: Its role in vascular inflammation and atherosclerosis

The nuclear protein high mobility group box 1 (HMGB1) has been suggested to be involved in the pathogenesis of several vascular diseases such as systemic vasculitis and atherosclerosis. In systemic vasculitides including ANCA-associated vasculitis and Kawasaki disease, serum HMGB1 levels are higher in patients with active disease compared to healthy controls. In atherosclerotic disease, HMGB1 displays increased expression in nuclei and cytoplasm of macrophages and smooth muscle cells in the atherosclerotic lesions, and is implicated in the progression of the atherosclerotic plaque. Experimental models of acute coronary syndromes and cerebrovascular accidents show that HMGB1 is not only involved in the amplification of the inflammatory response during acute ischemic injury, but also in the recovery and remodeling process after ischemia. Patients with acute coronary syndromes or stroke present significantly higher serum levels of HMGB1 than healthy controls and levels are associated with disease severity and mortality. Here we review clinical and experimental studies dealing with the role of HMGB1 in vascular diseases.     

Role of polymorphonucleocyte-produced leukotriene B4 in Kawasaki disease]

It is postulated that inflammatory cells play an important role in the process of developing vasculitis in Kawasaki Disease. LTB4, a 5-lipoxygenase product of arachidonic acid is one of the most potent chemoattractants to inflammatory cells and is produced in large amounts by PMNs. We investigated the role of PMN-derived LTB4 in Kawasaki Disease. Isolated PMNs were obtained from 19 Kawasaki disease patients in three different phases of the illness, (acute phase: 0-12th day, convalescent phase: 13-29th day, restored phase: greater than 30th day). LTB4 synthesis in the convalescent phase was 26.43 +/- 4.2 ng/5 x 10(6) cells, which was significantly higher than those in the acute and restored phases (11.90 +/- 1.91, 13.87 +/- 1.86 ng) and also higher than that in the control subjects (10.65 +/- 1.26 ng: p less than 0.05). No differences were found between two groups with or without coronary lesions. The results imply that activated PMNs during the convalescent phase of illness produce larger amount of LTB4 which may participate in the development of inflammatory process of the disease and that PMN-derived LTB4 plays no significant roles in the development of coronary lesions.     

T cell Vbeta repertoires in childhood vasculitides

Superantigens (SAgs) are potent stimulators of T cells bearing specific Vβ T cell receptors (TCR) and may play a role in the aetiopathogenesis of systemic vasculitis, although this remains contentious. To investigate the possible aetiological role of SAgs, this study examined peripheral blood T cell Vβ repertoires in children with systemic vasculitis. FACS analysis of 17 different peripheral blood T cell Vβ families was performed in 20 healthy control children, 27 disease control children with nonvasculitic inflammatory disease, 25 children with primary systemic vasculitis, six patients with Kawasaki disease (KD) and six patients with Henoch–Schönlein purpura (HSP). There was a significantly increased variance of CD4 Vβ12 and Vβ17, and CD8 Vβ1 in the primary systemic vasculitis group compared to control and disease controls. Moreover, 80% of the primary systemic vasculitis children had one or more CD4 Vβ expansions or deletions, compared with 30% of controls (P < 0·002), and 37% of the disease controls (P < 0·002). In the KD group, the mean percentage of CD4 Vβ2 T cells was higher than in controls or disease controls. In the HSP group, there was no consistent skewing of the T cell Vβ repertoire. We have observed changes in the T cell Vβ repertoire in children with vasculitis over and above those observed in disease controls. While these data provide impetus for further research into this contentious field, they do not resolve unequivocally the question of the role of SAgs in childhood vasculitic syndromes.     

Genetic variants in the HLA-G region are associated with Kawasaki disease

Kawasaki disease is an acute, self-limited vasculitis of infants and children, manifest as fever and signs of mucocutaneous inflammation. Treatment with high-dose immunoglobulin reduces systemic inflammation and prevents coronary artery lesions in Kawasaki disease. In this study, we investigated the possible association of the major histocompatibililty complex (MHC) region for the susceptibility to Kawasaki disease using an MHC panel of 2360 single nucleotide polymorphism (SNP) markers. Analysis of data obtained from screening MHC-specific SNP chips with 48 case and 90 control subjects revealed five candidate loci with significance levels of uncorrected p < 0.01. However, only one candidate locus (HLA-G) was confirmed to have a significant association with Kawasaki disease (rs2523790, odds ratio [OR] = 3.00, 95% confidence interval [95% CI] = 1.14–7.91, uncorrected p = 0.0263) in the replication study using 44 new case subjects and the previous 90 controls. In the fine mapping of the HLA-G locus, in particular, a nonsynonymous SNP (C/A) of the HLA-G gene (rs12722477, Leu134Ile) was significantly associated with Kawasaki disease (OR = 3.23, 95% CI = 1.12–9.32). A subgroup analysis showed that this association was more apparent in patients with coronary artery aneurysms (OR = 4.02, 95% CI = 1.23–13.19). Therefore, our results indicate that HLA-G may play a crucial role for the susceptibility to Kawasaki disease.     

Increased CD11b expression on polymorphonuclear leucocytes and cytokine profiles in patients with Kawasaki disease

Clinical evidence implicates polymorphonuclear leucocytes in the pathogenesis of vasculitis in Kawasaki disease. We examined modulation of expression of adhesion molecules (CD11b and CD62L) on polymorphonuclear leucocytes and how this expression is related to serum cytokine concentrations. In 18 patients with Kawasaki disease and 15 control subjects, adhesion molecule expression was determined by two-colour immunofluorescence staining of blood leucocytes and flow cytometry. Eight cytokines and chemokines were also measured. In patients with Kawasaki disease, mean fluorescence intensity for CD11b before giving intravenous immunoglobulin was significantly higher than in normal subjects (P<0 x 005). After intravenous immunoglobulin, mean fluorescence intensity for CD11b decreased significantly. With coronary artery lesions present, mean CD11b fluorescence intensity was significantly higher than without coronary artery lesions (P=0 x 005 before intravenous immunoglobulin; P=0 x 024 after intravenous immunoglobulin). No differences were seen in CD62L expression on polymorphonuclear leucocytes between patients with Kawasaki disease and normal subjects. CD11b expression on polymorphonuclear leucocytes correlated positively with serum interleukin (IL)-6, IL-10, granulocyte colony-stimulating factor, percentage of neutrophils among white cells and C-reactive protein. Polymorphonuclear leucocytes from patients with Kawasaki disease showed increased CD11b expression, which was associated with increased serum cytokines and appeared to be related to coronary artery lesions.     

Serum autoantibodies profile and increased levels of circulating intercellular adhesion molecule-1: a reflection of the immunologically mediated systemic vasculopathy in rheumatic diseases?

The clinical manifestation of systemic vasculitis may be postulated as a consequence of immune response abnormalities in the course of connective tissue diseases (CTD). The aim of this study was to elucidate the significance of the different autoantibodies and soluble intercellular adhesion molecule 1 (sICAM-1) being shed into the circulation in the diagnosis of vasculitis in rheumatic diseases. Sera of 86 patients with rheumatic diseases (54 with rheumatoid arthritis (RA) and 32 with CTD) were analyzed for the concentrations of sICAM-1 levels by the enzyme-linked immunosorbent assay (ELISA). Control sera were obtained from 30 healthy individuals. Anti-nuclear antibodies (ANA), anti-double-stranded DNA (anti-dsDNA) antibodies and anti-proteinase 3 (PR-3) antibodies (cytoplasmic specific anti-neutrophil cytoplasmic autoantibodies, cANCA) were assessed by the ELISA method. Fifty out of the 86 patients had systemic lesions. A pathological picture of the vascular loop under nailfold capillary microscopy was found in 84 patients. In 19 patients the microvascular changes were advanced, in 35 moderate and in 30 mild. All patients with articular manifestations had pathological changes under capillary microscopy. Patients with advanced changes under capillary microscopy had longer disease durations than patients with a mild intensity of vasculitis. The serum concentrations of sICAM-1 were significantly increased in RA and CTD patients compared with 30 controls (in both cases p<0.001). Moreover, RA and CTD patients with systemic vasculitis showed significantly higher levels of sICAM-1 than those without vascular involvement (p<0.001 and p<0.005 respectively). ANA were observed in significantly elevated concentration among RA and CTD patients with the systemic damage compared with patients without organ injury (p<0.001 and p<0.05 respectively). Also, cANCA levels were two-fold higher, but only among CTD patients with systemic damage (p<0.05). Serum concentrations of sICAM-1 were elevated in the patients showing the presence of ANA antibodies (p<0.05). Significant correlations between ANA level and disease duration and hemoglobin concentration were observed. The concentrations of cANCA correlated with those of rheumatoid factor and of dsDNA with patient age. We conclude that systemic lesions in the course of RA and CTD are accompanied by the microvascular injury observed under nailfold capillary microscopy. Our data suggest that sICAM-1, ANA and cANCA serum levels may reflect the extent of the vascular involvement in RA and CTD patients.     

Combined steroid-cyclosporin treatment of chronic autoimmune diseases

Summary Twenty-one patients suffering from different autoimmune diseases (14 from systemic lupus erythematosus, 4 from rheumatoid arthritis, one from Sjögren's syndrome, one from systemic hypersensitivity vasculitis, and one from diffuse proliferative glomerulonephritis) were treated with a combined immuno-suppressive regimen. Cyclosporin was given at a dose of 5 mg/kg/day together with steroids. In addition, the rheumatoid arthritis patients also received methotrexate. In all patients a kidney biopsy was performed after a treatment period of 17 to 42 months (mean duration 21.7 months). The cumulative cyclosporin dose at the time of biopsy varied from 1.071 to 4.587 mg/kg. Patients suffering from systemic lupus erythematosus and rheumatoid arthritis were assessed according to a scoring system set up for this purpose. The combined therapy proved useful in these patients as reflected in the diminution of the respective activity scores, improvement of kidney function, and diminution of proteinuria. Histological examination of the kidney biopsy specimens showed only minimal activity in patients with systemic lupus erythematosus. No unequivocal signs of renal toxicity could be detected. In the last group, the condition of the patient with Sjögren's syndrome was stabilized and the patient with systemic vasculitis improved clinically. Neither patient had signs of kidney lesions. The patient with diffuse proliferative glomerulonephritis, in whom kidney biopsy was performed before and after treatment, showed improvement of kidney function, diminution of proteinuria, and diminution of inflammatory activity within the kidney, and no signs of cyclosporin toxicity.Abbreviations CyA Cyclosporin - MTX Methotrexate - NSAID Nonsteroidal antiinflammatory drugs - RA Rheumatoid arthritis - SLE Systemic lupus erythematosus - TFA index Index of extent of tubular atrophy, intersitital fibrosis, and arteriolopathy     

CTLA-4, Position 49 A/G Polymorphism Associated with Coronary Artery Lesions in Kawasaki Disease

Objective  

Kawasaki disease (KD) is a systemic vasculitis of unknown etiology and primarily affects children less than 5 years of age. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) has been suggested as a candidate gene for conferring susceptibility to autoimmunity. This study examined the correlation of CTLA-4 gene polymorphisms in KD with and without coronary artery lesions (CAL).     

2020 international consensus on ANCA testing beyond systemic vasculitis

This document follows up on a 2017 revised international consensus on anti-neutrophil cytoplasm antibodies (ANCA) testing in granulomatosis with polyangiitis and microscopic polyangiitis and focuses on the clinical and diagnostic value of ANCA detection in patients with connective tissue diseases, idiopathic interstitial pneumonia, autoimmune liver diseases, inflammatory bowel diseases, anti-glomerular basement membrane (GBM) disease, infections, malignancy, and during drug treatment. Current evidence suggests that in certain settings beyond systemic vasculitis, ANCA may have clinical, pathogenic and/or diagnostic relevance. Antigen-specific ANCA targeting proteinase-3 and myeloperoxidase should be tested by solid phase immunoassays in any patient with clinical features suggesting ANCA-associated vasculitis and in all patients with anti-GBM disease, idiopathic interstitial pneumonia, and infective endocarditis associated with nephritis, whereas in patients with other aforementioned disorders routine ANCA testing is not recommended. Among patients with autoimmune liver diseases or inflammatory bowel diseases, ANCA testing may be justified in patients with suspected autoimmune hepatitis type 1 who do not have conventional autoantibodies or in case of diagnostic uncertainty to discriminate ulcerative colitis from Crohn’s disease. In these cases, ANCA should be tested by indirect immunofluorescence as the target antigens are not yet well characterized. Many questions concerning the optimal use of ANCA testing in patients without ANCA-associated vasculitis remain to be answered.     

Significance of isolated vasculitis in the gynecological tract: what clinicians do with the pathologic diagnosis of vasculitis?

Vasculitides includes a heterogeneous group of disorders with the common histologic findings of vascular wall inflammation. Systemic or localized disease (eg, renal vasculitis) has serious consequences. The incidence of isolated gynecologic vasculitis diagnosed on pathology specimens and its significance is little known. We performed a 20 year retrospective review including 53 cases with vasculitis diagnosis affecting the female genital tract identified in pathology reports. None had prior symptoms or were diagnosed with generalized vasculitis, while one patient had prior diagnosis of fibromyalgia. Most patients presented with abnormal bleeding and were treated for conditions unrelated to vasculitis. The different types of vasculitis were: predominantly lymphocytic (nonspecific) 30 cases, necrotizing 17 cases and granulomatous 6 cases. Only 2 patients had additional serologic tests. None of the patients with isolated gynecologic vasculitis received corticosteroids or additional treatment related to the vasculitis. None of the patients developed systemic vasculitis at follow-up (2 months-19.5 years; mean, 5.5 years). Isolated gynecologic vasculitis diagnosed on pathology slides is rarely associated with systemic vasculitis. Potential isolated gynecologic vasculitis causes include: previous surgical interventions and vascular inflammation secondary to local neoplasm. In almost all cases, clinicians did not perform a thorough laboratory analysis to exclude systemic vasculitis and therapy was not required in any case, suggesting minimal clinical significance.     

Current clinical and therapeutic approach to tumour-like mass lesions in granulomatosis with polyangiitis

Granulomatosis with polyangiitis (GPA) is a systemic autoimmune disorder classified among the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and characterized by a triad of upper and lower respiratory tract disease, systemic vasculitis involving small-to-medium vessels and renal manifestations. Mass lesions, also described as inflammatory lesions, pseudotumor or tumour-like masses, are uncommon manifestations of GPA and are often called granuloma since histology examination shows granulomatous inflammation and rarely vasculitis. Masses could represent a localized manifestation of GPA or develop as part of a systemic disease. Unusual clinical presentation together with nonspecific radiological and histological features may delay the correct diagnosis leading to disease progression and organ damage. Diagnosis of GPA in such cases may be challenging and malignancy or infections must be considered as alternative diagnostic options. Here we reviewed all the different sites where mass lesions were reported in GPA, focusing on atypical localization, and summarized current therapeutic options and their different outcomes. We retrieved and discussed the cases reported since 2010, bearing in mind the advances in the therapeutic management of AAV patients in the last decade, namely biological therapy such as rituximab. Despite treatment regimens with glucocorticoids and immunosuppressive agents, mass lesions have a refractory course in a high proportion of patients. Invasive surgical procedures may be considered only when drug therapy fails.     

Autoimmune/inflammatory syndrome induced by adjuvants—ASIA—related to biomaterials: analysis of 45 cases and comprehensive review of the literature

Systemic autoimmune or granulomatous disorders related to biomaterials of human use have rarely been described. The aim of this study was to report cases of autoimmune/inflammatory syndrome induced by adjuvants (ASIA) related to biomaterial injections and prostheses, mainly silicone, hyaluronic acid, acrylamides and methacrylate compounds in a Spanish patient cohort. This study is a retrospective analysis of clinical, laboratory, histopathological and follow-up data of 45 cases of patients suffering from late-onset, non-infectious inflammatory/autoimmune disorders related to bioimplants. Late onset was defined as 3 months or more post injection. Data were obtained through a further non-systematic but comprehensive review of the literature. Forty-five cases of late-onset adverse reactions related to biomaterial injections or prostheses were reviewed. All cases had systemic complaints that could be categorised as ASIA. In all but four patients, inflammatory features at the implantation site preceded distant or systemic manifestations. Abnormal blood tests were common. Localised inflammatory nodules and panniculitis in 40/45 (88.88%) evolved into a variety of disorders, viz., primary biliary cirrhosis, Sjögren’s syndrome, sarcoidosis, human adjuvant disease, vasculitis, inflammatory bowel syndrome and inflammatory polyradiculopathy. Five (11.11%) cases presented primarily with systemic autoimmune disorders. Biomaterials and prostheses can provoke late-onset systemic autoimmune disorders fulfilling ASIA criteria, or present primarily local/regional inflammatory reactions that may eventually evolve into systemic autoimmune and/or granulomatous disorders which fall under ASIA.     

Glomerular vascular cell adhesion molecule-1 expression in renal vasculitis.

AIMS: To study the expression of cell adhesion molecules in the renal biopsy specimens of patients with systemic vasculitis and Henoch-Schönlein purpura (HSP); to correlate this with the severity of glomerular inflammation. METHODS: Renal biopsy specimens obtained from eight patients with untreated systemic vasculitis (four with Wegener's granulomatosis and four with microscopic polyarteritis), eight with HSP and nine controls (four with normal histopathology and five with thin glomerular basement membrane disease) were stained using the alkaline phosphatase anti-alkaline phosphatase method with monoclonal antibodies directed against intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. RESULTS: Biopsy specimens of normal kidneys expressed ICAM-1 in glomerular endocapillary cells, Bowman's capsule epithelium, interstitial cells and interstitial vascular endothelium, and VCAM-1 in Bowman's capsule epithelium, proximal tubular epithelium and interstitial vascular endothelium. No staining with antibody directed against E-selectin was seen in any of the biopsy specimens. Biopsy specimens of patients with a vasculitic glomerulonephritis (segmental necrotising glomerulonephritis) expressed VCAM-1 in glomerular endocapillary cells (four of eight patients with systemic vasculitis; two of eight patients with HSP). In patients with a systemic vasculitis glomerular VCAM-1 expression was associated with a more severe renal lesoin (44, 50, 60, and 65% of glomeruli involved) than in those not showing glomerular VCAM-1 expression (3, 3, 11, and 39% of glomeruli involved). CONCLUSION: Expression of VCAM-1 by glomerular endocapillary cells in renal biopsy specimens raises the possibility that recruitment of VLA-4 bearing leucocytes may contribute to glomerular injury in Wegener's granulomatosis and microscopic polyarteritis.     

Six cases of microscopic polyarteritis exhibiting acute interstitial pneumonia

Out of 21 autopsy cases of microscopic polyarteritis (MPA), six cases that died of acute respiratory failure are described. All of these six cases exhibited pauci-immune necrotizing glomerulonephritis. Of these six cases, systemic vasculitis and respiratory failure occurred almost simultaneously in two, whereas respiratory failure developed when vasculitis recurred in the other four. Pathologically, pulmonary changes were diffuse and almost uniform in each case. Interstitial inflammatory cells (alveolitis), hyaline membrane, restructuring, and fibrosis were observed. The degrees of these changes differed from case to case; four cases showed predominantly exudative changes and two cases exhibited proliferative or organizing ones. Clinical and pathological features were consistent with acute interstitial pneumonia (Alp). lmmunofluorescent and ultrastructural studies did not suggest deposition of immune complexes at the lesions of alveolitis. An etiologic agent could not be identified in these cases. Some lung lesions inciuding pulmonary hemorrhage have been described in association with MPA; however, cases such as those presented here have rarely been reported. It was considered that AIP could be one of the pulmonary disorders in MPA. Furthermore, the possible pathogenetic role of antineutrophil cytoplasmic antibodies (ANCA) in the evolution of present lung lesion is discussed. Although ANCA were not examined in the present cases, these antibodies should be investigated in future cases.     

Skin involvement in cutaneous and systemic vasculitis

Cutaneous vasculitides are a heterogeneous group of inflammatory disorders affecting skin blood vessels. They may be triggered by several factors, such as infection or drug, or may be related to underlying disease, notably connective tissue or malignancies. However, vasculitis occurs without any demonstrable triggering agents in a relevant number of patients. On the other hand, vasculitic skin lesions may manifest as a component of vasculitis affecting also internal organs; in someone of these patients, skin involvement occurs initially as the sole sign of disease, leading to consider cutaneous vasculitis a diagnosis of exclusion. In this review, we have focused on the most common variants of cutaneous vasculitis, including cutaneous small vessel vasculitis and urticarial vasculitis as well as Henoch–Schönlein purpura, a systemic form in which however skin involvement often predominates. We have also argued on livedoid vasculopathy, a cutaneous entity which, although nonfrankly vasculitic in origin, is frequently associated with connective tissue disease. Finally, we have analyzed the variety of cutaneous manifestations that may develop during the course of the main systemic vasculitides, such as Wegener's granulomatosis, Churg–Strauss syndrome and polyarteritis nodosa.     

Genetic Basis of the Complex Pathological Manifestations of Collagen Disease: Lessons from MRL/lpr and Related Mouse Models

The pathological findings in collagen disease including systemic lupus erythematosus show complex lesions such as glomerulonephritis, systemic vasculitis, polyarthritis, sialoadenitis, etc. Moreover, some cases of collagen disease are categorized into overlapping syndromes. It is still controversial whether such diversity and similarity of pathological manifestations among the collagen disease depends on ambiguity in diagnosis or is an intrinsic quality of the collagen diseases themselves. In this paper, we reviewed this subject focusing on a series of our genetic studies of murine models of collagen disease, MRL strains of mice with a deficit in Fas-mediated apoptosis, which spontaneously develop glomerulonephritis, systemic vasculitis, polyarthritis and sialoadenitis. We observed that each lesion was controlled by a different set of genes and they appeared to act in an additve manner on the development of each lesion. We conclude that various disease categories in collagen disease will be a result of the combination of poly genes.