Fibrosing vasculitis in Wegener's granulomatosis: ultrastructural and immunohistochemical analysis of the vascular lesions

Interstital lung disease in ANCA vasculitis

Anti-neutrophil cytoplasmic antibodies (ANCA) vasculitides are immune-mediated disorders that primarily affect small blood vessels of the airway and kidneys. Lung involvement, one of the hallmarks of microscopic polyangiitis and granulomatosis with polyangiitis, is associated with increased mortality and morbidity. In recent years, several retrospective series and case reports have described the association of interstitial lung disease (ILD) and ANCA vasculitis, particularly those positive for ANCA specific for myeloperoxidase. In the majority of these patients pulmonary fibrosis occurs concurrently or predates the diagnosis of ANCA vasculitis. More importantly, these studies have shown that ILD has an adverse impact on the long-term prognosis of ANCA vasculitis. This review focuses on the main clinical and radiologic features of pulmonary fibrosis associated with anti-neutrophil cytoplasmic antibodies. Major histopathology features, prognosis and therapeutic options are summarized.

Pulmonary involvements of anti-neutrophil cytoplasmic autoantibody-associated renal vasculitis in Japan

BACKGROUND

Pulmonary involvement is one of the hallmark lesions of anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) as well as rapidly progressive glomerulonephritis (RPGN). However, the pulmonary involvement of AAV patients seems to differ between Europe and Japan, as does the ANCA serotype.

METHODS

This retrospective and prospective multicenter cohort study collected the clinical data of the features and outcomes of 1772 RPGN patients treated from 1989 to 2007 in Japan. Based on this nationwide RPGN survey, we analyzed the cases of 1147 AAV patients.

RESULTS

We found that 52.3% of the AAV patients had pulmonary involvements: 15.4% of the AAV patients had alveolar hemorrhage (AH), 26.2% had interstitial lung disease (ILD), 2.8% had bronchial asthma, 2.4% had pulmonary granuloma and 12.8% had a chest X-ray abnormality without AH, ILD or pulmonary granuloma. Patient survival was significantly different among the following six groups: the 5-year survival rate was 41.5% in the patients with AH, 50.2% in those with ILD, 67.9% in those with bronchial asthma, 62.5% in those with pulmonary granuloma, 55.8% in those with chest X-ray abnormality and 73.3% in those without pulmonary involvement. AH was one of the predictors of 1- and 5-year mortality for patient survival in AAV, and ILD was added as one of the predictors of 5-year mortality.

CONCLUSION

In these AAV patients, not only AH but also ILD was frequently observed. AH was associated with the prognosis, but ILD was associated with the long-term prognosis of AAV.

Conidiobolomycosis in a young Malaysian woman showing chronic localized fibrosing leukocytoclastic vasculitis: a case report and meta-analysis focusing on clinicopathologic and therapeutic correlations with outcome

BACKGROUND

Conidiobolomycosis (also known as rhinoentomophthoramycosis) is a rare cutaneous/mucosal fungal infection seen mainly in the tropical rain forest regions of the world that can be associated with disfiguring facial elephantiasis, and rarely, death.

OBJECTIVE

To present an exemplary case report and perform a systematic review of the world's literature to more accurately describe the natural history and the effect of therapy on outcome in conidiobolomycosis.

METHODS

Case report and meta-analysis of published case reports and series of conidiobolomycosis to determine which clinical, pathologic, mycologic, and treatment factors impact on prognosis.

RESULTS

We document delay in diagnosis of conidiobolomycosis in a young Malaysian woman, whose biopsy showed pathognomonic features-massive tissue eosinophilia and Splendore-Hoeppli phenomenon surrounding broad hyphae. These findings coexisted with granuloma faciale-like changes (fibrosing leukocytoclastic vasculitis) and lymphedema. Treatment with multiple antifungals was followed by complete resolution. For the meta-analysis, pooled data from 199 cases (162 with full outcome data) from 120 reports revealed a similar course for most cases: a disease affecting healthy young adults who present with progressive nasal symptoms (eg, nasal obstruction) and central facial swelling and show improvement or cure after surgical excision and/or treatment with one or more antifungal agents in 83%. Persistent-progressive facial disease occurred in 11%, and 6% died rapidly of fungal infection. Presentation with facial elephantiasis correlated with persistent-progressive rhinoentomophthoramycosis and a longer duration of disease before diagnosis (P = 0.02). Lethal infections were significantly associated with nonstereotypical presentation (eg, orbital cellulitis), visceral infection, absence of the Splendore-Hoeppli phenomenon, presence of comorbidities (eg, immunosuppression, hematolymphoid malignancy), infection with Conidiobolus incongruus or Conidiobolus lamprauges (not Conidiobolus coronatus), lack of response to amphotericin B, and female sex (all P ≤ 0.002). The few sensitivity studies performed demonstrated in vitro multidrug resistance of Conidiobolus species to most available antifungal agents.

LIMITATIONS

Publication bias, reporting heterogeneity, and data deficits may affect results.

CONCLUSIONS

Conidiobolomycosis should be included in the differential diagnosis of patients who present with nasal symptoms and painless centrofacial swelling. Massive tissue eosinophilia and Splendore-Hoeppli material coating thin-walled hyphae confirms the clinical diagnosis. The granuloma faciale-like histology found in this case can explain the onset of facial lymphedema by fibroinflammatory destruction of lymphatic vessels; the duration of disease and severity of inflammation likely predicts whether the lymphedema is reversible or not. Although rhinoentomophthoramycosis ostensibly responds in vivo to most available antifungal agents, routine culture and susceptibility testing is recommended to better define the efficacy of these therapeutic agents.

Interstitial lung disease and ANCA-associated vasculitis: a retrospective observational cohort study

OBJECTIVES

ANCA-associated vasculitis and interstitial lung disease (ILD) are uncommon conditions. The occurrence of both diseases in the same patient is increasingly recognized. Our aim was to ascertain the characteristics and outcomes of patients with ILD and ANCA-associated vasculitis.

METHODS

A retrospective observational cohort study was performed. Patients who presented to the Hammersmith Hospital, London, with ANCA-associated vasculitis [granulomatosis with polyangiitis (Wegener's), microscopic polyangiitis (MPA) or Churg-Strauss syndrome] who also had ILD were included. Following hospital discharge, all patients were followed up in a multi-disciplinary vasculitis clinic. We recorded patient demographics, diagnostic tests, treatment, complications and mortality.

RESULTS

ILD was observed in 2.7% (n = 14) of our patients with ANCA-associated vasculitis (n = 510); all had MPO-ANCA and a clinical diagnosis of MPA, giving a prevalence of 7.2% in patients with MPA (n = 194). There was no significant difference in survival between patients with MPA and ILD and those with MPA alone.

CONCLUSION

It is important that physicians are aware of this clinical association and the presence of ILD should be considered in all patients with ANCA-associated vasculitis, especially those with MPO-ANCA. The possibility that patients with ILD may subsequently develop features of systemic vasculitis should also be remembered.

The histological assessment of cutaneous vasculitis

Vasculitis is defined as inflammation directed at vessels, which compromises or destroys the vessel wall leading to haemorrhagic and/or ischaemic events. Skin biopsy is the gold standard for the diagnosis of cutaneous vasculitis, whose manifestations include urticaria, infiltrative erythema, petechiae, purpura, purpuric papules, haemorrhagic vesicles and bullae, nodules, livedo racemosa, deep (punched out) ulcers and digital gangrene. These varied morphologies are a direct reflection of size of the vessels and extent of the vascular bed affected, ranging from a vasculitis affecting few superficial, small vessels in petechial eruptions to extensive pan-dermal small vessel vasculitis in haemorrhagic bullae to muscular vessel vasculitis in lower extremity nodules with livedo racemosa. Skin biopsy, extending to subcutis and taken from the earliest, most symptomatic, reddish or purpuric lesion is crucial for obtaining a high-yielding diagnostic sample. Based on histology, vasculitis can be classified on the size of vessels affected and the dominant immune cell mediating the inflammation (e.g. neutrophilic, granulomatous, lymphocytic, or eosinophilic). Disruption of small vessels by inflammatory cells, deposition of fibrin within the lumen and/or vessel wall coupled with nuclear debris allows for the confident recognition of small vessel, mostly neutrophilic vasculitis (also known as leukocytoclastic vasculitis). In contrast, muscular vessel vasculitis can be identified solely by infiltration of its wall by inflammatory cells. Extravasation of red blood cells (purpura) and necrosis are supportive, but not diagnostic of vasculitis as they are also seen in haemorrhagic and/or vaso-occlusive disorders (pseudovasculitis). Vasculitic foci associated with extravascular granulomas (palisaded neutrophilic and granulomatous dermatitis), tissue eosinophilia, or tissue neutrophilia signal the risk for, or co-existence of systemic disease. This essential histological information coupled with direct immunofluorescence and anti-neutrophil cytoplasmic data and clinical findings enables more precise and accurate diagnosis of localized and systemic vasculitis syndromes.

The role of tenascin-C in tissue injury and tumorigenesis

The extracellular matrix molecule tenascin-C is highly expressed during embryonic development, tissue repair and in pathological situations such as chronic inflammation and cancer. Tenascin-C interacts with several other extracellular matrix molecules and cell-surface receptors, thus affecting tissue architecture, tissue resilience and cell responses. Tenascin-C modulates cell migration, proliferation and cellular signaling through induction of pro-inflammatory cytokines and oncogenic signaling molecules amongst other mechanisms. Given the causal role of inflammation in cancer progression, common mechanisms might be controlled by tenascin-C during both events. Drugs targeting the expression or function of tenascin-C or the tenascin-C protein itself are currently being developed and some drugs have already reached advanced clinical trials. This generates hope that increased knowledge about tenascin-C will further improve management of diseases with high tenascin-C expression such as chronic inflammation, heart failure, artheriosclerosis and cancer.

The role of tenascin-C in tissue injury and tumorigenesis

The extracellular matrix molecule tenascin-C is highly expressed during embryonic development, tissue repair and in pathological situations such as chronic inflammation and cancer. Tenascin-C interacts with several other extracellular matrix molecules and cell-surface receptors, thus affecting tissue architecture, tissue resilience and cell responses. Tenascin-C modulates cell migration, proliferation and cellular signaling through induction of pro-inflammatory cytokines and oncogenic signaling molecules amongst other mechanisms. Given the causal role of inflammation in cancer progression, common mechanisms might be controlled by tenascin-C during both events. Drugs targeting the expression or function of tenascin-C or the tenascin-C protein itself are currently being developed and some drugs have already reached advanced clinical trials. This generates hope that increased knowledge about tenascin-C will further improve management of diseases with high tenascin-C expression such as chronic inflammation, heart failure, artheriosclerosis and cancer.

Massive coats disease-like tumor after retinal detachment

PURPOSE

To describe two patients with peripheral Coats disease-like tumor reaction years after surgical repair for rhegmatogenous retinal detachment.

METHODS

Retrospective review of two clinical cases.

RESULTS

Patient 1 presented with visual deterioration caused by a retinal angiomatous tumor and lipid exudates originating from telangiectatic vessels on the scleral buckle 8 years after vitrectomy and encircling band surgery for a giant retinal tear. In Patient 2, a vascularized retinal mass was detected during vitrectomy for a vitreous hemorrhage 24 years after scleral buckling procedures. Both patients were highly myopic and had no history of scleral perforation or angiomatous proliferation before surgery. They underwent vitrectomy and removal of the vascularized tumor. Histologic examination revealed wide lacunae filled with erythrocytes, connective tissue strands with inflammatory cells, and capillaries that showed thickened multilamellar basement membranes.

CONCLUSION

Secondary Coats disease-like tumor reaction may occur as a late complication years after successful retinal detachment surgery and may be caused by a chronic ischemic and inflammatory stimulus induced by prominent buckling elements in highly myopic eyes.

Sclerosing Wegener's granulomatosis in the orbit

PURPOSE

To report three cases of sclerosing Wegener's granulomatosis in the orbit and to compare the histopathological morphology with those of other types of sclerosing orbital inflammation.

METHODS

We analysed the clinical data along with histopathological specimens from orbital biopsies and from two enucleated eyes.

RESULTS

All three patients had longstanding inflammation in the orbit and involvement of the paranasal sinuses. Proptosis, impaired ocular motility and reduced visual acuity dominated the clinical picture. All histopathological specimens featured granulomatous inflammation, tissue necrosis, vasculitis and widespread dense fibrosis. In certain areas of all specimens the fibrous tissue was arranged in characteristic concentric, onionskin-like whorls of collagen around obliterated small blood vessels.

CONCLUSIONS

Wegener's granulomatosis may lead to orbital fibrosis and sclerosis. The stromal changes and cellular infiltrate resemble the non-specific orbital inflammation previously termed orbital pseudotumour. We present the first 'onionskin' lesions in association with Wegener's granulomatosis in the orbit. This latter morphology may represent an abnormal fibrotic reaction in inflammatory tissue.

Specificity of intertubular capillary changes: comparative ultrastructural studies in renal allografts and native kidneys

The pathophysiology of chronic rejection of renal allografts is poorly understood and specific morphologic markers are being sought for its diagnosis. Ultrastructural splitting and reduplication of the basal lamina of the intertubular capillaries (ITCs) have been shown to be consistently associated with transplant glomerulopathy (TG) in renal allografts and have been used as a marker of chronic allograft rejection. Although the presence of ITC abnormalities is extremely helpful diagnostically and has been considered a surrogate for the diagnosis of TG when glomeruli are not available for examination, their specificity has not been tested. This study examined 135 biopsy specimens from renal allografts and native kidneys and categorized the ITC basal lamina alterations into 5 patterns. The results showed that although marked ITC basal lamina abnormalities are characteristically seen in association with TG, lesser degrees of these changes may also be found in native kidneys and in transplants with other types of glomerulopathies. In native kidneys, splitting and reduplication of the ITC basal lamina were observed in cases of active lupus nephritis, membranoproliferative glomerulonephritis type I, crescentic glomerulonephritis, cryoglobulinemia, and hypertension. In allografts, ITC changes were seen in postinfectious proliferative glomerulonephritis, acute cyclosporin toxicity, and hemolytic uremic syndrome, in addition to cases with TG. The histopathologic diagnosis in renal diseases relies heavily on clinical, immunofluorescence, and ultrastructural findings. Therefore, in the transplantation setting, with other less common pathological processes ruled out, the presence of abnormalities of the ITC basal lamina is highly indicative of TG. This association is particularly true for cases with severe ITC abnormalities.