Circulating immunoglobulin complexes in Wegener's granulomatosis

Complement in ANCA-associated glomerulonephritis

Background

Anti-neutrophil cytoplasmic antibodies (ANCA) are found in pauci-immune necrotizing crescentic glomerulonephritis. In the past, the role of complement in ANCA-associated vasculitis (AAV) was assumed to be minimal. More recently, however, it was found that blocking the complement cascade in a mouse model of AAV reduces glomerular damage. Immune complex deposits have been found in biopsies from AAV patients. In this study, we questioned whether immune complex formation or deposition may result in complement activation in ANCA-associated glomerulonephritis.

Methods

ANCA-positive patients from the Limburg Renal Registry were included between 1979 and 2011. Renal histology was documented together with immunoglobulin and complement immunofluorescence. In addition, C3d, properdin, C4d and mannose-binding lectin (MBL) were stained. Electron microscopy was performed. Circulating immune complexes were determined in a subset of patients, as well as C3 allotypes.

Results

C3c was found in 78 of 187 renal biopsies (41.7%) divided over 32.3% of proteinase-3 (PR3)-AAV patients and 52.3% of myeloperoxidase (MPO)-AAV patients (P = 0.006), whereas C3d was found positive in 51.1% of PR3-AAV patients and 70.4% of MPO-AAV patients (P = 0.105). C4d was found positive in 70.8%, properdin in 38.7% and MBL in 30.4% of patients. Whereas C4d and MBL positivity was similar between the AGN groups, properdin was more common in biopsies classified as crescentic compared with biopsies classified as focal or mixed. Renal biopsies positive for C3d and/or properdin showed more cellular crescents and less normal glomeruli compared with biopsies negative for C3d and/or properdin (P < 0.05). In 3 out of 43 renal biopsies analysed by electron microscopy, small electron dense deposits were found. In 14 of 46 patients analysed, circulating immune complexes were detectable. No association between histological findings and C3 allotypes was found.

Conclusions

In the majority of AAV patients, no immune complex deposits were found in their renal biopsies. C3d, C4d and C5b-9 staining, however, was found to be positive in a majority of analysed renal biopsies. Importantly, C3d and properdin staining was associated with cellular crescents. We hypothesize that local immune complexes are quickly degraded in AAV and therefore not visible by electron microscopy. Our findings are compatible with the hypothesis that complement activation in AAV occurs predominantly via alternative pathway activation.

Vasculitides throughout history and their clinical treatment today

Therapeutic management of the vasculitides is closely linked to modern rheumatologic advances, particularly as it relates to the discovery and first clinical use of glucocorticoids. These compounds were introduced in the late-1940s for the treatment of rheumatoid arthritis, but soon after, clinicians in Europe and the United States realized that they could have a significant positive impact in systemic vasculitides. However, once it was realized that glucocorticoid use was associated with a high degree of morbidity, the search for better immunosuppressive agents with similar efficacy but improved safety profiles was on. During the past several years, several agents have been utilized for the therapeutic management of systemic vasculitides, and the list keeps growing with the development of newer compounds that have retained efficacy but with a better safety profile.

Are antineutrophil cytoplasmic antibody-associated vasculitides pauci-immune?

The role of ICs in ANCA-associated vasculitides remains controversial. The ANCA-associated vasculitides are described as being pauci-immune. We hypothesize that the absence of ICs is a result of an exaggerated inflammatory response caused by the presence of ANCAs. We present evidence indicating that ICs may play a role in the initiation or relapses of the disease. The nature of the involved antigen(s) is not yet known. Possible candidates are reviewed and include ANCA antigens, AECA antigens, and staphylococcal antigens.

Distinctive pathologic findings in proximal diabetic neuropathy (diabetic amyotrophy)

OBJECTIVE

To investigate the pathogenesis of proximal diabetic neuropathy (PDN) with nerve and muscle biopsies.

BACKGROUND

Recent evidence suggests that nerve ischemia secondary to immune-mediated vasculopathy rather than diabetic microangiopathy may be responsible for PDN.

METHOD

- Fifteen patients with PDN and two diabetic controls underwent nerve and muscle biopsy and clinical, electrophysiologic, and laboratory evaluation. There were eight men and seven women between 49 and 79 years of age with type II diabetes. All had progressive, painful, asymmetric, proximal weakness with duration of 5 weeks to 12 months. None had evidence of systemic autoimmune disorder.

RESULTS

Four patients showed the distinctive findings of polymorphonuclear small-vessel vasculitis affecting epineurial vessels with transmural infiltration of postcapillary venules with polymorphonuclear leukocytes. Immunoglobulin M (IgM) deposits were found along the endothelium and intramurally in affected vessels. IgM staining was seen in the subperineurial space and in the endoneurium. Activated complement deposition was seen along endothelium of small vessels. Three of these four patients were evaluated within 6 seeks of onset of PDN, and the fourth patient during acute flare of PDN 6 months after the initial onset. Six patients showed "perivasculitis" with mononuclear cell infiltrates around small epineurial vessels without vasculitis (fibrinoid necrosis or transmural inflammation). One patient showed recanalized vessels with transmural lymphocytes without fibrinoid necrosis, possibly suggesting healed vasculitis.

CONCLUSION

These distinctive pathologic findings support that proximal diabetic neuropathy has an immune-mediated inflammatory basis and suggest that polymorphonuclear vasculitis with immune complex and complement deposition may be the primary event in the acute phase of proximal diabetic neuropathy.

Case report: Wegener's granulomatosis accompanied by communicating hydrocephalus

A case of Wegener's granulomatosis (WG) accompanied by communicating hydrocephalus is described. An elderly woman with rapidly progressive renal failure was referred to the authors' hospital. Renal histologic study showed necrotizing granulomatous glomerulonephritis with some multinucleated giant cells, which suggested a diagnosis of WG. After admission, a gait disturbance, incontinence, and dementia developed in the patient. Diagnostic procedures including lumbar puncture, computed tomography (CT), and scintigraphy showed findings compatible with communicating hydrocephalus with a normal cerebrospinal fluid (CSF) pressure. Removal of 20 mL of CSF led to a marked improvement in symptoms. Because the presence of subarachnoid hemorrhage, meningitis, and brain tumor was excluded, the final diagnosis was communicating hydrocephalus secondary to WG.

Necrotizing scleritis after ocular surgery. A clinicopathologic study

Necrotizing scleritis may appear after trauma to the sclera. The authors studied 10 patients in whom necrotizing scleritis developed after ocular surgery. The interval between surgery and onset of scleritis varied from 2 weeks to 6 months. Nine patients (90%) were found to have an underlying autoimmune vasculitic systemic disease, which was subsequently treated with immunosuppression. One patient was found to have a local infectious process, which was treated with antibiotics. Appropriate studies led to the discovery and subsequent treatment of a systemic disease or an infectious process in 6 of the 10 patients; the other 4 patients had been previously diagnosed. Results of immunohistochemical studies on resected conjunctival and/or sclera suggest local immune complex deposition, increased HLA-DR expression, and increased helper T-cell participation in conjunctiva and/or scleral tissues after trauma in patients with underlying systemic autoimmune vasculitic disease. The results emphasize the need for meticulous diagnostic pursuit of potentially lethal systemic autoimmune vasculitic disease in patients with necrotizing scleritis after intraocular surgery.

Autoantibodies in systemic vasculitis

We have studied 495 sera that were referred to us from patients suspected on clinical and/or histological grounds to have a small vessel vasculitis. These sera were tested for antibodies against neutrophil cytoplasm antigens (anti-neutrophil cytoplasm antibodies, ANCA) using assays based on neutrophil acid extract, myeloperoxidase and elastase. Such antibodies are commonly found in Wegener's granulomatosis (WG) and microscopic polyarteritis (MPA), and sometimes in other small vessel vasculitides. One hundred and twenty-six of these sera (25%) were positive in the acid extract ELISA, 68 (14%) in the assay for anti-myeloperoxidase antibodies and 35 (16%) in the assay for anti-elastase antibodies. A total of 166 sera (34%) were positive for antibodies against neutrophil cytoplasm constituents. No ANCA, anti-myeloperoxidase or anti-elastase antibodies were detected in 26 convalescent sera from patients either with WG or MPA, or who had previously been positive. The mean time between positive and negative sera was eight weeks (range three weeks to six months) and three out of three who relapsed again developed ANCA of the same specificity as the original sera. Of the 228 sera also tested for anti-GBM antibodies, 13 (5.7%) were positive. All these contained antibodies against neutrophil cytoplasm constituents (three against the acid extract, eight against myeloperoxidase and two against elastase). Forty-nine of the 74 sera (66%) tested for ANA were positive. Twenty-nine (39%) had a speckled and 20 (27%) had a homogeneous pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

Diverse target antigens recognized by circulating antibodies in anti-neutrophil cytoplasm antibody-associated renal vasculitides

Antibodies that are directed against cytoplasmic constituents of neutrophils and monocytes (anti-neutrophil cytoplasm antibodies, ANCA) have been described in Wegener's granulomatosis, microscopic polyarteritis (MPA) and some cases of segmental necrotizing glomerulonephritis (SNGN). Other antibodies occasionally described in Wegener's granulomatosis and MPA include anti-nuclear antibodies (ANA) and anti-glomerular basement membrane (GBM) antibodies. We have studied the diversity of the corresponding antigens in ANCA-associated renal diseases. Sera from 46 patients with active histologically proven Wegener's granulomatosis, MPA and SNGN were tested for ANCA by indirect immunofluorescent examination of normal peripheral blood neutrophils. Thirty-four sera (74%) were positive; 16 were associated with diffuse cytoplasmic staining (cANCA) and 18 with perinuclear staining (pANCA). In addition, five demonstrated antineutrophil-specific nuclear staining (ANNA). On Western blotting of the neutrophil extract, five sera recognized a 29-kD molecule recently identified as neutrophil proteinase 3. Two sera with typical cANCA bound to molecules of 36, 38 and 116 kD and another to a molecule of 22 kD. The final serum associated with pANCA bound to a molecule of about 12 kD. Thirteen sera out of 46 (28%) tested in an ELISA contained anti-myeloperoxidase antibodies; 10 of these were associated with pANCA and two others with ANNA. Three sera of 17 (18%) tested contained anti-elastase antibodies; these also contained anti-myeloperoxidase antibodies and were associated with pANCA. However, eight sera with pANCA were negative for anti-myeloperoxidase antibodies and three of these were also negative for anti-elastase antibodies, suggesting further unidentified target antigen or antigens associated with the pANCA. Fifteen of the 34 sera positive for ANCA also demonstrated anti-nuclear staining on Hep-2 cells (53%) in a speckled, homogeneous, or nucleolar pattern. ANA were significantly associated with the presence of pANCA (P less than 0.01), and levels of ANA and ANCA fell in parallel after treatment. One serum with a pANCA was also positive for anti-GBM antibodies. Inhibition studies using ELISAs for anti-GBM antibodies indicated that there was no cross-reactivity between target molecules recognized by these antibodies. The diversity of target molecules recognized by ANCA suggests that cross-reactivity with bacterial structures is less likely as the primary aetiological event in the development of these antibodies than tissue destruction; and that cross-reactivity with vascular endothelium is also unlikely as the pathogenetic basis of vessel disease.

Perianal ulcer: an unusual presentation of Wegener's granulomatosis. Report of a case

A 46-year-old man, without remarkable past medical history, had a perianal ulcer that appeared spontaneously two months before presentation. At admission, the ulcer was painless, measuring 4 to 5 cm in diameter and showing detachment and a slightly papillomatous aspect at the edge but without induration of the base. Microscopic examination revealed cutaneous ulceration with a well-developed inflammatory response, a few small vessels with intraluminal thrombosis or necrotizing walls, and isolated microscopic granulomata. No infectious disease was detected. The diagnosis of Wegener's granulomatosis was made six months later, when the disease was clinically evident in three principal sites: upper airways, lung, and kidney. At that time, serum antineutrophil cytoplasmic autoantibodies were detected with indirect immunofluorescence microscopy. There has been an excellent response to immunosuppressive therapy. Review of the literature revealed no similar reports.

Pulmonary Wegener's granulomatosis. A clinical and imaging study of 77 cases

We studied 77 patients with biopsy-proven WG and pulmonary manifestations, to characterize the nature and frequency of the clinical, imaging and endoscopic features of this condition. Pulmonary symptoms were cough, mild dyspnea, hemoptysis and chest pain. Five patients had no pulmonary symptoms. Imaging features consisted of nodules, infiltrates and pleural opacities. A CT scan proved useful by disclosing cavities in opacities or opacities which were not seen on an x-ray film. Fiberoptic bronchoscopy was performed in 74 patients, and it was macroscopically abnormal in 55 percent (showing bronchial inflammation or stenosis or both or isolated hemorrhage). Six patients presented with alveolar hemorrhagic syndrome. Four patients had a pleural exudate rich in polymorphonuclear leukocytes. The WG was limited to the lung in seven patients. Sixteen patients died because of active disease or iatrogenic complications (two). An improved knowledge of clinical and imaging features of WG could help the clinician reach an earlier diagnosis.

Ear involvement in Wegener's granulomatosis

In 16 of 19 patients with biopsy-proved Wegener's granulomatosis the early manifestations were limited to the ear and nose. The audiological data of 13 patients revealed middle ear involvement in 16 of 26 ears. Twenty-one of 26 ears presented with a low to moderate sensorineural hearing loss. One ear remained deaf after a sudden hearing loss in the early stage of the disease. Serologically, 4 of 6 tested patients with sensorineural hearing loss demonstrated antibodies against sarcolemma. One patient showed antinuclear antibodies. It is remarkable that these antibodies can often be detected in classic inner ear disorders. The course of inner ear function, serum findings and the success of immunosuppressive therapy in Wegener's granulomatosis are comparable with immunologically mediated vasculitis in the inner ear.

Limbal allergic granulomatosis

Four limbal diseases characterised by granuloma formation as part of an allergic response are discussed. A series of histological specimens from patients with Wegener's granulomatosis were re-examined. Genuine granulomatous disease at the limbus is rare, only occurring in two patients, whilst secondary, more non-specific limbal active chronic inflammation was more common. Comparisons between this disease, Churg Strauss allergic angiitis, some varieties of Mooren's ulcer and allergic granulomatous nodules were made. The role of the mast cell in promoting this eosinophilic leucocytic mediated group of disease is discussed briefly.

Necrotizing vasculitis with granulomatosis

Table 1 summarizes some of the differentiating characteristics among these diseases. Clinically, the differentiating features are that classic Wegener's granulomatosis involves both the upper and lower respiratory systems and kidneys. Renal involvement is the major cause of morbidity and mortality. Churg-Strauss syndrome has the distinguishing characteristics of an allergic asthmatic prodrome and a profound eosinophilia. It encompasses and destroy's tissue not only of the lungs but also most of the other organ systems in the body. A major cause of mortality is cardiac disease, which is not a feature of either of the other two diseases. Finally, lymphomatoid granulomatosis is seen predominantly in the lungs, skin, and central nervous system and is the only one of the three that is associated with the development of a lymphoma. Although there are definitive clinical differences of these entities, as mentioned above, it is the histopathologic features that can diagnostically separate the three. Wegener's granulomatosis is predominantly a necrotizing granulomatous infiltrate that has a polymorphous infiltrate of neutrophils, plasma cells, and histiocytes and is very distinct from the eosinophilic granulomas of CSS or the lymphocytic ones of LYG. Finally, all of the diseases respond differently to medications. Patients with Churg-Strauss syndrome for the most part respond well to high dosages of oral steroids and usually do not require therapy with immunosuppressive agents. Therapy with steroids alone is not adequate for the treatment of Wegener's granulomatosis, and the therapy is a combination of steroids with chemotherapeutic agents, cyclophosphamide being the agent of choice. The most difficult disease to treat in this review is LYG.(ABSTRACT TRUNCATED AT 250 WORDS)

Ocular involvement in the respiratory vasculitides

The respiratory vasculitides are idiopathic inflammatory syndromes, characteristically involving the pulmonary vasculature as well as that of several other organ systems. The inflammatory response in these diseases is uniformly granulomatous. There are three distinct, recognized respiratory vasculitides: Wegener's granulomatosis, Churg-Strauss syndrome (allergic granulomatosis and angiitis), and lymphomatoid granulomatosis. Each of these entities may have ophthalmic manifestations, and ocular involvement may, in fact, be the presenting sign. The systemic and ocular manifestations, as well as the differential diagnosis and management of each of these entities are discussed.

Autoantibodies against neutrophils and monocytes: tool for diagnosis and marker of disease activity in Wegener's granulomatosis

Immunoglobulin G (IgG) autoantibodies against extranuclear components of polymorphonuclear granulocytes were detected in 25 of 27 serum samples from patients with active Wegener's granulomatosis and in only 4 of 32 samples from patients without signs of disease activity. In a prospective study of 19 patients these antibodies proved to be better markers of disease activity than several other laboratory measurements used previously. The autoantibodies were disease specific and the titres were related to the results of an in-vitro granulocyte phagocytosis test, in which 7S IgG antibodies were internalised after specific binding to the cell, resulting in gradual formation of ring-like cytoplasmic structures. This autoantibody may have a pathogenetic role in Wegener's granulomatosis. The detection of this antibody is valuable for diagnosis and estimation of disease activity.

Wegener's granulomatosis in childhood: cutaneous manifestations as the presenting signs

Wegener's granulomatosis (WG), characterized by a necrotizing granulomatous vasculitis, is a rare systemic disease particularly infrequent in children. We report an unusual case of WG in a 16-year-old male patient in whom the cutaneous manifestations were the presenting signs that preceded the upper respiratory symptoms by several months. In addition, the finding of a calcified pulmonary lesion has never been reported in association with WG. Accurate diagnosis of early skin lesions is important in view of the available effective therapy. Clinical and pathologic features of WG and treatment are reviewed.

Renal failure in Wegener's granulomatosis: recovering following dialysis and cyclophosphamide-prednisone therapy

Two patients with Wegener's granulomatosis, crescentic glomerulonephritis, and severe renal failure are described. Both patients required hemodialysis for control of uremic symptoms. Cyclophosphamide-prednisone therapy successfully controlled the extra-renal manifestations of their disease and reversed the renal failure so that dialysis could be discontinued.

Granulomatous glomerulonephritis in Wegener's granulomatosis

Review of the kidneys in 24 autopsy cases of Wegener's granulomatosis revealed a significant granulomatous glomerular lesion in eight of the cases. To gain a better understanding of this peculiar lesion, focusing on its pathogenesis, we attempted a thorough investigation on both glomerular and vascular lesions of the kidneys. Semiquantitative analysis of the glomerular lesions indicated that existence of a severe glomerular damage probably constitutes a necessary condition in the development of granulomatous glomerulonephritis, because the granulomatous glomerular lesion was typically seen in company with a widely distributed glomerular lesion represented by thrombotic and necrotic occlusion of capillary tufts and crescent formation. Necrotizing vasculitis in the kidney was always encountered, especially in small branches of renal arteries and vasa recta. A serial section study of the two most typical cases indicated that granulomatous inflammation apparently originated in hilar arteriolitis , which extended along the pericapsular space and developed into diffusely circumferential periglomerular inflammation. We conclude that two factors are jointly at work, one inside and the other outside of the glomerulus in the pathogenesis of granulomatous glomerulonephritis: there is a thrombotic and necrotic lesion of the glomerular tuft, on the one hand and pericapsulitis originating in hilar arteriolitis on the other.

SSA (Ro)-antibodies in Wegener's granulomatosis

In 4 consecutive cases of Wegener's granulomatosis with glomerulonephritis, antibodies against the extractable nuclear antigen SSA (Ro) could be demonstrated with counterimmunoelectrophoresis. Antibodies were demonstrable on admission and paralleled disease activity while patients were under therapy. This potential serological marker may be of value for diagnosis and follow-up of patients with Wegener's granulomatosis.

Pulmonary vasculitis (Wegener's granulomatosis). Immunohistochemical study of T and B cell markers

A case of pulmonary vasculitis (Wegener's granulomatosis) is reported in which immunoperoxidase studies demonstrated that the vascular lymphoid infiltrates were composed predominantly of T cells and monocytes. Occasional T cells, B cells and monocytes were identified in the alveolar septa. IgG, IgA, IgM, and C3 were not identified in pulmonary vessels, septa, or alveoli. These findings suggest that cellular rather than humoral-immune mechanisms predominate in pulmonary vasculitis.

Lymphomatoid granulomatosis: an analysis of clinical and immunologic characteristics

Six patients with lymphomatoid granulomatosis were studied. Two patients had eye involvement, a rare manifestation of this disease. Both had complete disappearance of disease in this area after radiation therapy. One patient presented with an autoimmune hemolytic anemia, which remitted completely with chemotherapy. The use of corticosteroids or chemotherapy was effective in bringing about a decrease in pulmonary infiltrates in all six patients, although the duration of response was limited. One patient did have a prolonged period of clinical remission, and died of an unrelated cause. Evidence of profound immunologic abnormalities was found in these patients by a variety of tests. The extensive immunologic dysfunction present in patients with lymphomatoid granulomatosis has not previously been described. Most strikingly, patients with lymphomatoid granulomatosis have a severe impairment in T-lymphocyte function, confirmed by their inability to react to common skin test antigens or dinitrochlorobenzene, decreased in vitro lymphocyte responsiveness to mitogens and antigens and changes in T-cell subset populations. This may account for the frequent development of malignant lymphomas in patients with this condition.

Pulmonary immune complex deposition in Wegener's granulomatosis

Two male patients with pulmonary manifestations of Wegener's granulomatosis are presented. One had an elevated rheumatoid factor, and both had elevated levels of immunoglobulin E. Both demonstrated characteristic necrotizing granulomatous lesions on light microscopy of lung tissue. Immunohistologic analysis of lung tissue demonstrated a granular deposition of immunoglobulin G and complement. Raji cell assay of sera demonstrated elevated levels of circulating immune complexes in the sera of the one patient tested prior to any therapy. These findings support the hypothesis that immune complex deposition contributes to the pathogenesis of Wegener's granulomatosis.

Wegener's granulomatosis. Electron microscopic and immunofluorescent studies

We report a case of classic Wegener's granulomatosis. Direct immunofluorescent study showed finely granular deposits of IgG and IgM in some of the alveolar walls, and of IgM in the maxillary sinus arteries. Electron-microscopic study of the lung and maxillary sinus showed intravascular fibrin, but failed to demonstrate electron-dense deposits in the blood vessel walls. Our patient also had circulating cryoglobulins, consisting of IgG, IgM, Clq, and C3, and evidence of circulating immune complexes as demonstrated by the Clq-binding test. These findings suggest that circulating immune complexes may play an important role in the pathogenesis of the respiratory lesions of Wegener's granulomatosis.

Wegener's granulomatosis exhibiting the clinical features of Goodpasture's syndrome

A case is reported here, the clinical features of which raised the suspicion of Goodpasture's syndrome which was, however, at variance with the absence of antiglomerular basement membrane antibodies. Renal failure improved on immunosuppressive treatment and peritoneal dialysis, but the patient died of gastric haemorrhage from a peptic ulcer related to steroid treatment. Necropsy and microscopic study revealed abnormalities of liver and spleen, consistent with Wegener's granulomatosis. Immunohistologic studies of the kidney confirmed the presence of granular-type IgG deposits in the glomeruli. There were extensive fibrin deposits in the kidney. The ways and means for the differentiation of Wegener's granulomatosis from Goodpasture's syndrome, the potential pathogenetic role of immunocomplexes and fibrin deposits, and the therapeutic possibilities are discussed.

The protracted superficial phenomenon in pathergic (Wegener's) granulomatosis

Twelve cases of pathergic (Wegener's) granulomatosis are described, with special attention focused on the long duration of mucosal and skin lesions in untreated cases, designated as the protracted superficial phenomenon, and on the histologic features that may be helpful in making the diagnosis. The long duration, often the result of a lack of proper interpretation of histologic details, was associated in some of the cases studied with the development of intractable renal failure or mutilation of the face. Since cytotoxic therapy offers the opportunity to prevent these complications, the desirability of an early diagnosis is obvious. Biopsy is the principal means of diagnosis, and therefore interpretation of histologic details is of paramount importance. Helpful histologic features found in the extravascular and vascular tissues of the specimens studed were focal necrosis, fibrinoid degeneration, palisading granulomas, giant cells, and vasculitis. Nonpalisading foci of granular necrosis or fibrinoid degeneration appeared to precede the development of the typical palisading granuloma. Both focal necrosis and focal fibrinoid degeneration occurred independently of intrinsic vascular involvement and in themselves are distinctive features of pathergic (Wegener's) granulomatosis. There was predominance of the extravascular components in the cases studied with occasional absence of vasculitis. Both the extravascular and vascular components are important in making a definitive diagnosis, but the extravascular component is characteristic, even in the absence of vasculitis. The extravascular tissues and the vessels are parallel contemporaneous target tissues.

Granulomatous vasculitis of Wegener

We report a case of granulomatous vasculitis of Wegener. Systemic involvement occurred in spite of chemotherapy and concomitantly with the development of immunological disturbances. The differential diagnosis with other angiocentric granulomatoses and the estimation of the risk of extension to internal organs are primordial because of their prognostic importance.

Soluble immune complexes in human disease

The great variety in biochemical properties of immune complexes occurring in human and animal disease states has made the detection of such complexes a difficult task. Variability in immune complex size, specificity, and interaction with humoral or cellular receptor systems, such as complement and phagocytes, suggests different pathogenic properties. The introduction of radioimmunoassays and the recently improved knowledge of the immune complex-receptor interactions have lead to the description of a large number of detection procedures, which in turn has widened the catalogue of diseases associated with immune complexes. This widespread occurrence of soluble immune complexes has lead many investigators to think that such complexes may occur either as a transient physiological phenomenon, important for fast clearance of the antigen, or as primary pathogenic factors triggering inflammatory reactions. Among the 50 procedures for immune complex detection known today, the article will select some pertinent tests, which will be discussed with respect to their specificity, sensitivity, and reproducibility. Furthermore, it is well known that when applied to the study of a patient group with one particular immune complex disease, various tests will result in different percentages of patients having complexes. This observation is due to differences in the underlying principle on which the various tests are based. Thus immune complexes must be further characterized with respect to their size, to the antibody class or specificity involved and, most difficult, to the antigenic specificity which participates in the complex. Recent advances in such experimental characterization of immune complexes in vitro and in the clinical evaluation of patients with complement activation associated to the presence of immune complexes will be discussed.

Relapsing polychondritis with crescentic glomerulonephritis

Relapsing polychondritis is rare and its cause is unknown. The tissues affected are those with a high glycosaminoglycan content, such as cartilage, the aorta, the sclera and cornea, and parts of the ear. Symptoms can usually be controlled with oral steroids, but when there is coexistent progressive crescentic glomerulonephritis quadruple chemotherapy may be used. Three cases of the clinical syndrome of relapsing polychondritis were studied in which rapidly progressive cresentic glomerulonephritis developed. In two the patients appeared to respond to aggressive treatment with immunosuppressive agents and anticoagulants. The multisystemic nature of the disease, the renal lesions, and the response to treatment all suggested that the condition might be related to periarteritis nodosa.