Vascular Disease in Scleroderma

Gastric and enteric involvement in progressive systemic sclerosis

Progressive systemic sclerosis (PSS) is a chronic multisystem disease characterized by excess deposition of connective tissue in skin and internal organs, associated with microvasculature changes and immunologic abnormalities. Involvement of the gastrointestinal tract may occur in 2 stages, a neuropathic disorder followed by a myopathy. Gastric emptying is delayed in 10% to 75% of patients and correlates with symptoms of early satiety, bloating, and emesis. Compliance of the fundus is increased although perception of fullness is normal. Myoelectric abnormalities have been found in some studies. Treatments include metoclopramide, cisapride, and erythromycin. Bleeding from telangiectasias and watermelon stomach is treated endoscopically. Small bowel involvement in PSS occurs in 17% to 57% of patients. The migrating motor complexes are reduced or absent, predisposing to bacterial overgrowth. Malabsorption may also be due to pancreatic insufficiency. Barium enemas demonstrate pancolonic involvement in 10% to 50% of patients with PSS. Wide-mouthed diverticuli, involving all layers of the intestinal wall, are characteristic. Pseudoobstruction may respond to octreotide or prucalopride therapy. Complications include pneumatosis cystoides intestinalis, stercoral ulcerations, and perforation. Fecal incontinence may be due to dysfunction of the internal anal sphincter, a smooth muscle responsible for most of the resting anal sphincter pressure. Anal manometry may show a reduction or loss of the rectoanal inhibitory reflex. Treatments include biofeedback, sacral nerve stimulation, and surgery. PSS involves the gastrointestinal tract from the mouth to the anus. Studies are needed to define effective treatments in these diseases, which cause great morbidity.

Interstitial lung disease in systemic sclerosis

We reviewed the literature concerning pathogenesis, clinical features, diagnosis and treatment of interstitial lung disease (ILD) in patients with systemic sclerosis (SSc). ILD is detectable in approximately 70% of patients at autopsy. Nonspecific interstitial pneumonia (NSIP) is the most common pathologic finding. The earliest phase of ILD in SSc is characterized by microvascular injury and alveolitis. Endothelial lesions, activation of coagulation proteases, especially thrombin, fibroblast proliferation, and differentiation of normal lung fibroblasts to a myofibroblasts phenotype are hallmarks of ILD in SSc. Diagnostic procedures used to detect ILD are chest X-ray, high-resolution computed tomography, bronchoalveolar lavage, lung function tests, and sometimes thoracoscopic lung biopsy. Novel and potentially useful methods to diagnose ILD in SSc are induced sputum and technetium-labeled diethylenetriamine pentaacetate (99mTC-DTPA) clearance time. Cyclophosphamide seems to be relatively effective to treat ILD in the earliest phase, but the effects of other immunosuppressive drugs on the lungs are less convincing.

BDNF: a missing link between sympathetic dysfunction and inflammatory disease?

Nerve growth factor (NGF) plays a role in sympathetic neuron integrity and survival. Brain-derived neurotrophic factor (BDNF) also has trophic effects on sympathetic neurons. We report here the serendipitous finding that co-treatment of hippocampus with BDNF and the NGF antagonist TrkA-Fc leads to perivascular inflammation and marked vasoconstriction. This effect is not observed with either reagent alone or in combination with other control proteins. Because NGF supports sympathetic neuron health, we tested the hypothesis that BDNF combined with sympathetic compromise caused this effect. Superior cervical ganglia were removed bilaterally with concurrent BDNF infusion into hippocampus. Perivascular inflammation was observed at 3 days, but not 12 days post treatment, when sympathetic terminals had receded, suggesting that the presence of these terminals was necessary for inflammation. Since sympathetic dysfunction may lead to compensatory overactivity of norepinephrine (NE) signaling, we co-infused BDNF with NE in the hippocampus and observed perivascular inflammation. In humans, sympathetic overactivity has been reported in a variety of vascular diseases. Some of these diseases, e.g. primary Raynaud's, are not accompanied by serious inflammatory disease whereas others, such as scleroderma and systemic lupus, are. We speculate that BDNF may contribute to the transformation of sympathetic dysfunction to inflammatory disease.

Increase in platelet non-integrin type I collagen receptor in patients with systemic sclerosis

Microvascular injury is one of the major pathogenetic processes involved in systemic sclerosis (SSc). Interaction of the platelet types I and III collagen receptors with their respective ligand in the exposed subendothelial stroma as a result of ongoing microvascular injury in SSc patients results in platelet activation and aggregation with the release of mediators, which contribute to vascular damage and inflammation. We have found that there is a twofold increase in radiolabeled type I collagen binding to washed platelets from patients with SSc compared to platelets obtained from normal volunteers. Western blot analyses showed that the non-integrin platelet type I collagen receptor protein (65 kDa) is increased dramatically in lysates of platelet from patients with SSc. However, the integrin (alpha(2)beta(1)) and other non-integrin receptors such as glycoprotein VI, glycoprotein IV, and the platelet receptor for type III collagen remain unchanged. In addition, platelet lysates from rheumatic disease controls (rheumatoid arthritis, osteoarthritis, gout, and systemic lupus erythematosus) do not show any significant increases. There is no nitrotyrosylation on 65 kDa in patients with SSc compared to controls, suggesting this might also contribute to binding of CI to the 65-kDa CIR. These results suggest that there is a specific increase in the number of platelet type I collagen receptors in SSc patient's platelets. In addition, the activity of nitric oxide synthase is decreased in patients' platelet lysates compared to controls. The increase in platelet expression of the 65-kDa non-integrin platelet type I collagen receptor may explain the enhanced aggregation of platelets from patients with SSc to CI in vitro and microvascular thrombosis in the disease in vivo.

Lipoprotein profile in limited systemic sclerosis

The objective of this study was to determine the lipoprotein profile of limited cutaneous systemic sclerosis (LcSSc). Fasting lipids were determined in 24 female patients and 24 healthy age-matched and sex-matched controls. Exclusion criteria were conditions that induce an altered lipid profile. Lipoprotein levels of risk were determined in accordance with the National Cholesterol Education Program (NCEP). Significantly lower levels of high-density lipoprotein (HDL) cholesterol (47.6+/-12.4 mg dL(-1) vs. 58.2+/-12.3 mg dL(-1); P=0.003) and total cholesterol (197.0+/-40.7 mg dL(-1) vs. 222.0+/-34.0 mg dL(-1); P=0.02) were observed in LcSSc patients than in controls. The presence of anti-centromere antibodies (ACA) was also associated with lower HDL levels (45.0+/-12.1 mg dL(-1)) compared to ACA-negative patients and controls (50.2+/-12.6 and 58.2+/-12.3 mg dL(-1), respectively, P=0.01). The only clinical variable associated with low HDL levels was pulmonary hypertension (PH) (33.6+/-2.3 mg dL(-1) vs. 49.6+/-11.9 mg dL(-1), P=0.01). No significant correlation was observed among HDL levels and ESR (r=-0.313; P=0.14), CRP (r=-0.296; P=0.16), or BMI (r=-0.263; P=0.21). Remarkably, a higher percentage of risk HDL levels was identified in LcSSc patients (41.6%) than in healthy controls (8.3%) (P=0.02). Our data suggest that LcSSc patients, particularly those who are ACA positive, have an adverse lipid profile characterized by low HDL levels, a known independent risk for CAD in women. The relevance of this finding for the development of atherosclerosis in this disease must be confirmed by epidemiological studies.

Systemic sclerosis: the susceptible host (genetics and environment)

It is becoming evident that several genetic factors participate in modulating susceptibility to SSc and its clinical manifestations. Some genes that specifically affect ECM metabolism and vascular function may be unique to SSc and scleroderma-related disorders; others, such as those genes involved in regulating immune tolerance, are likely shared with other autoimmune diseases. The effect of genetic variations (or polymorphisms) that are found in most of these genes taken individually will likely have only a small or modest effect on disease risk; only a few genetic variations are expected to be highly penetrant. Moreover, genetic studies in SSc have to deal with the additional issues of heterogeneous phenotypes, low disease prevalence in the general population, and an even greater paucity of multiplex families that makes traditional linkage studies difficult, if not impossible. Alternative approaches include allelic association studies, but conventional case-controls designs may be subject to selection bias and will require large sample sizes if the genes that are under investigation confer only modest (OR = 1.5-2.0) disease risk (Fig. 2). The simultaneous examination of several genes that are biologically relevant to a specific disease process to attain higher aggregate ORs, is one approach that was used in several reports that were cited in this review. The use of family-based controls, such as in the transmission-disequilibrium test (based on assessment of the transmitted or nontransmitted alleles that are associated with disease from heterozygous parents to affected offspring), would provide more robustness to spurious associations from population stratification, but is actually less powerful and efficient than case-control designs. Furthermore, for many late adult-onset diseases the effort required to obtain samples from living parents are for a variety of reasons not trivial. The success of these allelic association-based approaches depends on the identification of likely candidate disease genes (or at least markers in disequilibrium with disease genes), careful definition/ascertainment of disease phenotypes to minimize genetic heterogeneity, and for case-control designs, strategies to account for population stratification or admixture. The identification of candidate genes will be aided by rapid progress in the Human Genome Project and other genome efforts that will eventually identify all human genetic variations. Although this will lead to better understanding of the genes that might be involved in complex diseases, much work is required to understand the basic biology of how disease genotypes become clinical phenotypes. This is especially daunting in complex diseases, such as SSc, where the phenotype (including disease susceptibility and clinical presentation) is influenced by dynamic interactions between genetic variations and environment. Multi-center collaborative efforts with research paradigms that integrate genetic and environmental factors (including sociodemographic variables) will be required to elucidate the contribution of environment and genetics in the pathogenesis of SSc.

Homocysteine and laminin are not prognostic markers in patients with septic inflammatory response syndrome

The aim of this study was to measure plasma homocysteine and laminin concentrations in patients with nonbacteremic systemic inflammatory response syndrome (SIRS) and to compare them with those of a healthy control group. Concerning laminin, significant increased concentrations could be observed in the SIRS group compared to the control group, but for homocysteine, no significance could be observed. In summary, homocysteine and laminin levels are not useful in the prediction of a patient's outcome.

Evidence for the Involvement of CD44 in Endothelial Cell Injury and Induction of Vascular Leak Syndrome by IL-2

At sites of chronic inflammation seen during infections, autoimmunity, graft-vs-host response, and cytokine therapy, endothelial cell injury is known to occur, the exact mechanism of which is unknown. In the current study we used IL-2-induced vascular leak syndrome (VLS) as a model to investigate whether cytotoxic lymphocytes use CD44 in mediating endothelial cell injury. Administration of IL-2 to wild-type mice triggered significant VLS in the lungs and liver. In contrast, in CD44 knockout (KO) mice, IL-2-induced VLS was markedly reduced in the lungs and liver. IL-2-treated wild-type and CD44 KO mice had similar levels of perivascular infiltration with lymphocytes in the lungs and liver. This suggested that the decrease in VLS seen in CD44 KO mice was not due to the inability of lymphocytes to migrate to these organs. Ultrastructural studies demonstrated extensive endothelial cell damage in the lungs and liver of IL-2-treated wild-type, but not CD44 KO, mice. Moreover, CD44-KO mice exhibited a marked decrease in IL-2-induced lymphokine-activated killer cell activity. The induction of VLS was dependent on the expression of CD44 on immune cells rather than endothelial cells because adoptive transfer of CD44+, but not CD44− spleen cells along with IL-2 into CD44 KO mice triggered VLS. The IL-2-induced VLS was blocked by administration of F(ab′)2 of Abs against CD44. The current study demonstrates that CD44 plays a key role in endothelial cell injury. Blocking CD44 in vivo may offer a novel therapeutic approach to prevent endothelial cell injury by cytotoxic lymphocytes in a variety of clinical disease models.

Up-regulation of class II major histocompatibility complex and intercellular adhesion molecule 1 expression on scleroderma fibroblasts and endothelial cells by interferon-gamma and tumor necrosis factor alpha in the early disease stage

OBJECTIVE

To investigate the expression patterns of interferon-gamma (IFN gamma) and tumor necrosis factor alpha (TNF alpha), both of which are potent inducers of class II major histocompatibility complex (MHC) and intercellular adhesion molecule 1 (ICAM-1) expression, and their codistribution with HLA-DR and ICAM-1 in skin lesions, cultured fibroblasts, and peripheral blood mononuclear cells (PBMC) of systemic sclerosis (SSc) patients in different stages of disease.

METHODS

Investigations were carried out using immunohistochemistry studies, reverse transcriptase-polymerase chain reaction, dot-blot hybridization, and cytometric analysis. Serum levels of TNF alpha were determined by enzyme-linked immunosorbent assay.

RESULTS

In the early inflammatory stage of SSc, class II MHC and ICAM-1 expression could be detected on most endothelial cells and on fibroblasts located especially in perivascular areas surrounded by infiltrating lymphocytes, which belong to the T helper 1 phenotype expressing IFN gamma and TNF alpha. In this early disease stage, an enhanced expression of TNF alpha on cultured dermal fibroblasts and PBMC, as well as elevated serum titers of soluble TNF alpha, could be found.

CONCLUSION

These data suggest that class II MHC antigens and ICAM-1 on fibroblasts and endothelial cells are induced by IFN gamma and TNF alpha in an early stage of SSc after the influx of mononuclear-cells, and may be important in the putative autoimmune response and in the perpetuation of fibrotic processes in SSc.

Serum laminin and basic fibroblast growth factor concentrations in patients with complicated Plasmodium falciparum malaria

Serum concentrations of laminin and basic fibroblast growth factor (FGF) were measured in 20 patients suffering from complicated Plasmodium falciparum malaria in Bangkok. Significant higher mean serum concentrations of laminin were determined prior to treatment (1973 ng/ml) and 7 days after starting medication (1025 ng/ml) in comparison to the control (412 ng/ml). The values remained numerically higher for at least 21 days. With regard to serum basic FGF concentrations, a peak was found 7 day after starting treatment (35.61 pg/ml). In addition, a significant correlation was found for parasite clearance time and basic FGF concentration on day 7 (P < 0.01). These increased values of laminin and basic FGF may be the consequence of endothelial and basement membrane damage induced by sequestration of the parasites. Furthermore, basic FGF might play a role in endothelial repair mechanisms after the clearance of the parasites.

Gastric antral vascular ectasia (watermelon stomach) in patients with systemic sclerosis

This report describes 5 patients with systemic sclerosis (SSc) who developed severe, recurrent upper gastrointestinal (GI) bleeding due to gastric antral vascular ectasia (GAVE). The clinical records, the endoscopic findings, and the histologic appearance of biopsy specimens and surgically resected gastric tissue from the patients were reviewed. All 5 patients developed severe and recurrent episodes of upper GI bleeding leading to severe anemia requiring multiple transfusions. The cutaneous involvement was diffuse in 3 patients and limited in 2. All but 1 had cutaneous telangiectasias. The diagnosis of GAVE was established by endoscopy within 3 years of the diagnosis of SSc in all cases. One patient required heater probe cautery, 2 required laser coagulation, and 2 underwent surgical resection of the gastric antrum for control of the GI bleeding. The possibility of GAVE should be considered in SSc patients who have recurrent upper GI bleeding. It is suggested that the antral vascular lesions in these patients may represent a component of the spectrum of vascular alterations of SSc.

Computer based quantitative analysis of capillary abnormalities in systemic sclerosis and its relation to plasma concentration of von Willebrand factor

OBJECTIVES

To evaluate an objective and quantitative method for assessment of capillary abnormalities in systemic sclerosis (SSc).

METHODS

Nailfold capillaries were investigated by capillary microscopy and photographed in 17 consecutive SSc patients (five with diffuse cutaneous systemic sclerosis (dSSc) and 12 with limited cutaneous systemic sclerosis (lSSc)) and in 17 healthy controls. Investigators having no access to clinical data made drawings from magnified projections of coded photographs and analysed them using a computer program. Capillary density (capillary loops/mm in the distal row) and median capillary loop area were calculated. Presence of functional or organic arterial changes was evaluated by measurement of finger pressure with finger cooling. Plasma concentration of von Willebrand factor (VWF) was analysed using an enzyme linked immunosorbent assay (ELISA).

RESULTS

In 16 of 17 SSc patients and 13 of 17 controls the technical quality of the photographs was sufficient for computer analysis. Capillary density was decreased in dSSc (median 6.9 loops/mm) and in lSSc (median 3.8 loops/mm) compared with healthy controls (8.9 loops/mm) and median capillary loop area was increased in dSSc (7.3 x 10(-3) mm2) and in lSSc (8.5 x 10(-3) mm2) compared with healthy controls (5.0 x 10(-3) mm2). An inverse relation was found between capillary density and median capillary loop area in SSc patients. Plasma VWF was increased in patients (median 401 IE/l in dSSc and 409 IE/l in lSSc) compared with controls matched for age and sex (median 276 IE/l). Computer based analysis showed capillary density below the control range and median capillary loop area above the control range in 14 of 16 SSc patients. Measurement of finger pressure with finger cooling showed organic vascular changes in nine of 13 SSc patients.

CONCLUSION

Computer based quantitative analysis has low interobserver variability and is a quantitative and sensitive method of assessing capillary abnormalities in SSc.

Increased susceptibility to oxidation of low-density lipoproteins isolated from patients with systemic sclerosis

OBJECTIVE

To examine the resistance to oxidation of low-density lipoproteins (LDL) from patients with systemic sclerosis (SSc) and primary Raynaud's phenomenon (RP) compared with healthy controls.

METHODS

Plasma LDL were isolated from patients with diffuse cutaneous and limited cutaneous SSc (dcSSc and lcSSc, respectively), patients with primary RP, and healthy control subjects. The lipoproteins were assessed for their resistance to oxidation in the presence of cupric ions, using spectrophotometric assays.

RESULTS

LDL from patients with dcSSc and lcSSc were more susceptible to oxidation than were those from healthy control subjects or patients with RP.

CONCLUSION

Our findings suggest that free radicals may play a role in the pathology of SSc.

Anti-neutrophil cytoplasm antibodies in patients with ACR criteria for polyarteritis nodosa: help for systemic vasculitis classification?

The american college of rheumatology (ACR) proposed in 1990 revised clinical criteria for systemic vasculitis classification to define homogeneous group of patients for clinical trials. However, microscopic polyarteritis (MPA) was not clearly identified from polyarteritis nodosa (PAN). Since anti-neutrophil cytoplasm antibodies (ANCA) are markers of disease activity of small vessel vasculitides including MPA, we tested the clinical significance of ANCA in 24 patients with PAN according to the ACR 1990 criteria. Two of 24 patients had ANCA, as defined by indirect immunofluorescence on normal human neutrophils, antigen-specific ELISA and Western blot analysis. However, they exhibited histologically proven small vessel but not medium vessel vasculitis. Furthermore, they had neither artery microaneurysms nor large organ injury consequent upon large vessel occlusion. Although they satisfied ACR criteria for PAN, they probably were misclassified and should be considered as MPA. We conclude that: (i) ANCA are not found in patients with classical PAN in the absence of MPA features; (ii) caution should be exercised when defining PAN according to the ACR 1990 criteria; (iii) ANCA may help systemic vasculitis classification.

Clinical significance of anticardiolipin antibodies in patients with systemic sclerosis

One hundred and three patients suffering from systemic sclerosis (SSc), with different extent of skin involvement, were retrospectively examined to investigate the correlations between clinical manifestations and anticardiolipin antibodies (aCL). aCL of IgG, IgA, and IgM classes were measured in the patients' sera by enzyme linked immunosorbent assay. aCL were found in 26 patients (25.2%). A significant association was found between aCL and myocardial ischaemia or necrosis (p = 0.011). No patient showed the clinical picture of the antiphospholipid syndrome. On the basis of clinical manifestations, a protocol for disease score was drawn. Patients with IgG-aCL and with IgA-aCL showed a disease score higher than aCL negative patients (p = 0.008 and p = 0.022 respectively). Thus, the finding of aCL can be considered a useful serological index for the most severe forms of SSc.

The vascular basement membrane in systemic sclerosis skin: heterogeneity of type IV collagen

In systemic sclerosis (SS) changes in the dermal microvasculature include endothelial cell damage, a reduction in the number of vessels, and vascular basement membrane thickening. The basement membrane is a critical component of the vessel, and alterations in its structure may lead to changes in the surrounding tissue. In SS the altered basement membrane is associated with the subsequent development of fibrosis. To investigate the relationship between vascular basement membrane changes in affected skin and disease progression, immunohistochemical analyses were performed using both polyclonal and monoclonal antibodies against type IV collagen, the major basement membrane collagen. Using two monoclonal antibodies directed against different conformational epitopes within the (alpha 1)2 (alpha 2) helical domain, type IV collagen was detected in normal skin, and uninvolved SS skin, but not in later grades of disease. Identical results were obtained using a monoclonal antibody against a sequential determinant on the denatured alpha 1 (IV) chain. The use of a polyclonal antibody, however, showed that type IV collagen was present in all grades of disease, suggesting an alteration in the composition of type IV collagen with disease progression.

Extracorporeal photochemotherapy in progressive systemic sclerosis

BACKGROUND

Extracorporeal photochemotherapy, an immune-modulating form of therapy, has been shown to be effective in the treatment of autoimmune diseases. We evaluated the effects of extracorporeal photochemotherapy in the treatment of patients with progressive systemic sclerosis (PSS).

METHODS

Nine patients with active progressive systemic sclerosis were treated with extracorporeal photochemotherapy on 2 successive days monthly. The duration of therapy ranged from 6 to 21 months.

RESULTS

A significant improvement was noted in the skin, musculoskeletal system, functional index, and symptoms including Raynaud's phenomenon, dyspnea, fatigue, dysphagia, and arthralgias, as well as improvement of cutaneous ulcers. Stabilization of the pulmonary function studies was also noted in the majority of patients over the course of therapy. No serious side effects were noted throughout the course of therapy in the 9 patients.

CONCLUSIONS

The results suggest that photopheresis may be beneficial in selected early cases of progressive systemic sclerosis.

A radical proposal for the pathogenesis of scleroderma

Because the etiology and pathogenesis of scleroderma are largely speculative, effective therapy is not available for this debilitating condition and its variants. This article reviews current concepts in the etiology and pathogenesis of scleroderma and suggests a unifying hypothesis involving the generation of free radicals. The role of specific free radical scavengers should be tested both in vitro and in clinical trials of patients with scleroderma.

Cytokine production and serum levels in systemic sclerosis

Serum levels of various cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin 1-beta (IL1-beta), and interleukin 2 (IL2), and of soluble IL2 receptors (sIL2R) were determined in 30 patients with definite systemic sclerosis (SSc). Spontaneous and lipopolysaccharide-or mitogen-induced production of the cytokines, TNF-alpha, IL1-beta, and IFN-gamma, by peripheral blood mononuclear cells (PBMNC) of these SSc patients was measured by immunoassays. The patients were divided into three groups: 12 with limited cutaneous disease (lcSSc), 7 with diffuse cutaneous disease (dcSSc) < 3 years duration, and 11 with dcSSc > 3 years duration. None were treated with cytotoxic drugs or biologic response modifiers. Sera of patients with SSc had elevated sIL2R levels, and only low levels of IL2 (1-2 U/ml) were detected in 10/29 sera tested. Spontaneous production of TNF-alpha and IL1-beta by PBMNC of patients with SSc (829 pg/ml +/- 215 SEM and 728 pg/ml +/- 186, respectively) was significantly higher than that by normal PBMNC obtained from 30 volunteers (25 +/- 10 and 34 +/- 6 pg/ml, respectively) and tested at the same time as patients' PBMNC. The largest increases in spontaneous release of TNF-alpha or IL1-beta were seen in patients with early dcSSc. No significant difference in spontaneous IFN-gamma production by patient or control PBMNC was detected. On the other hand, the mean level of mitogen-induced IFN-gamma production by PBMNC was significantly depressed in patients with SSc (103 U/ml +/- 18 vs 255 +/- 33 U/ml in controls). In vitro-induced production of TNF-alpha or IL1-beta by patients' PBMNC was comparable to that of normal PBMNC. These data indicate that in vivo-activated PBMNC of patients with SSc spontaneously secrete excessive amounts of fibrogenic cytokines, which are involved in modulation of connective tissue synthesis.

New perspectives on basic mechanisms in lung disease. 1. Lung injury, inflammatory mediators, and fibroblast activation in fibrosing alveolitis

It is over 25 years since Scadding first defined the term fibrosing alveolitis. It has since been established that complex mechanisms underlie its pathogenesis, including epithelial and endothelial injury, vascular leakage, production of inflammatory cells and their mediators, and fibroblast activation. Only through a detailed knowledge of how these cellular and molecular events are interlinked will we learn how to combat this disease, which is notoriously resistant to present treatments. So far the only therapeutic advances have been refinements in immunosuppression, and even these treatments are frequently disappointing. We believe that future advances in treatment will come from the development of agents that protect endothelial and epithelial cells from further injury and agents that can inhibit release of inflammatory mediators. A better knowledge of the mechanisms of collagen gene activation and the biochemical pathways of collagen production may also allow the identification of vulnerable sites at which new treatments may be directed. A combined approach to modifying appropriate parts of both the inflammatory component and the fibroblast/collagen component should provide a new stimulus to research. Further epidemiological studies are also needed to identify the environmental causes of lung injury that initiate the cascade of events leading to interstitial fibrosis.

Adhesion of peripheral blood mononuclear cells to vascular endothelium in patients with systemic sclerosis (scleroderma)

OBJECTIVE

Perivascular infiltrates in skin, subcutaneous tissue, and internal organs are a characteristic feature of early systemic sclerosis (SSc). We studied the first step of migration of peripheral blood mononuclear cells (PBMC) through the vessel wall to the extravascular space, i.e., adhesion of PBMC to endothelial cells (EC), in patients with various forms of SSc (limited scleroderma, diffuse scleroderma, and the transitional form).

METHODS

Radioisotope-labeled patient PBMC were coincubated with umbilical cord EC in vitro, and the percentage adhesion was measured.

RESULTS

Adhesion of PBMC to EC was markedly decreased, while adhesion of isolated active rosette-forming cells (ARFC) was significantly increased, in SSc patients compared with healthy controls. Decreased adhesion of PBMC to EC was found to correlate with a diminished percentage of ARFC in the peripheral blood. Preincubation of PBMC from healthy donors with interleukin-2 (IL-2) enhanced their adhesion to EC, while preincubation of PBMC from SSc patients with this cytokine resulted in a decrease in adhesion in 10 of 14 individuals. IL-1, interferon-gamma, and transforming growth factor beta had no significant effect on adhesion of SSc patient PBMC to EC. Differences in adhesion of PBMC to EC among the SSc subgroups were not significant.

CONCLUSION

Our findings suggest that in SSc, activation of subpopulations of PBMC leads to their enhanced adhesion to vascular endothelium in vivo and to migration of these cells to the extravascular space, resulting in the elimination from the peripheral blood of those PBMC with high ability to adhere to EC.

Anticentromere antibody as a predictor of digital ischemic loss in patients with systemic sclerosis

OBJECTIVE

To determine the clinical and serologic risk factors for digital ischemic events in patients with systemic sclerosis (SSc).

METHODS

Retrospective review of clinical and laboratory data and review of current clinical status of 98 patients with SSc, seen between 1985 and 1990.

RESULTS

Amputation of 1 or more digits due to ischemia occurred in 20.4% of the patients; 9.2% had multiple digit loss. Sclerodactyly alone and anticentromere antibody (ACA) were associated with loss of 1 or more digits. Age, smoking status, duration of disease, or duration of Raynaud's phenomenon were not predictive for loss of digits.

CONCLUSION

Patients with limited SSc who are positive for ACA have an increased risk of major peripheral vascular occlusive disease.

The fasciitis-panniculitis syndrome: clinical spectrum and response to cimetidine

The term fasciitis-panniculitis syndrome (FPS) is proposed as a novel compilation encompassing several disorders, common to which is subcutaneous induration caused by cicatrizing fasciitis as well as septal and lobular panniculitis and perimysial fibrosis. Included herein are Shulman's eosinophilic fasciitis, morphea profunda, lupus profundus, venous lipodermatosclerosis, toxic oil syndrome, altered tryptophane-related eosinophilic myositis, graft-versus-host reaction, and fasciitis reactive to subjacent basal cell carcinoma. FPS should be differentiated from scleroderma, which primarily affects the dermal structures and in which arterioles are injured. In contrast, vasculopathy of the subcutaneous medium-sized veins accompanies the hypodermal lesions of FPS. The importance of recognizing and grouping these disorders lies in their different histopathology, characterization as reactive phenomena, enhanced responsiveness to treatment, and better prognosis than scleroderma. In view of the excellent prognosis of FPS, steroid treatment is not warranted. Long-term therapy with cimetidine appears to benefit the majority of patients.

Clinical correlations of plasma angiotensin converting enzyme (ACE) activity in systemic sclerosis: a longitudinal study of plasma ACE level, endothelial injury and lung involvement

Lung involvement was studied by perfusion scan, ventilation scan, pulmonary clearance rate of 99mTc DTPA and pulmonary function tests in 20 patients with systemic sclerosis (SSc). Decreased plasma angiotensin converting enzyme (ACE) activity and increased levels of von Willebrand Factor Antigen (vWF:Ag) were found in all patients with SSc. The relationship between ACE levels and lung involvement was not statistically significant, however levels of vWF:Ag correlated with parameters of lung vascular alterations. An inverse relationship between the reduced ACE levels and ESR was found. It is likely that ACE levels reflect the inflammatory aspect of the disease. Further studies of ACE synthesis, release and inhibition are needed to determine the mechanism of the observed decreased activity in SSc.