Systemic sclerosis

The aryl hydrocarbon receptor: a review of its role in the physiology and pathology of the integument and its relationship to the tryptophan metabolism

The aryl hydrocarbon receptor (AHR) is a cytosolic receptor for low molecular weight molecules, of which the most widely recognized ligand is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and the most widely recognized effect, chloracne. Adverse effects of manipulation were most recently and graphically demonstrated by the poisoning of Viktor Yushchenko during the Ukrainian presidential elections of 2004. However, recent research has revealed a receptor with wide-ranging, and at times, paradoxical actions. It was arguably among the first biological receptors to be utilized by dermatologists, dating from the time of topical tar preparations as a therapeutic agent. I provide a review outlining the role AHR plays in the development, cellular oxidation/antioxidation, responses to ultraviolet light, melanogenesis, epidermal barrier function, and immune regulation and its relationship to tryptophan metabolism. Finally, I will review the role of AHR in diseases of the integument.

Clinical Results of Extracorporeal Photopheresis

Extracorporeal photopheresis (ECP) is a combination of leukapheresis and photodynamic therapy in which blood is treated with photoactivable drugs which are then activated with ultraviolet light and re-infused to the patient. It has been used successfully for more than 30 years in the treatment of erythrodermic cutaneous T-cell lymphoma (CTCL) and over 20 years for chronic graft-versus-host disease (GVHD). ECP has also shown promising results in the treatment of acute GVHD and other T-cell-mediated diseases, including systemic sclerosis, treatment and prevention of solid organ rejection, and more recently Crohn's disease. The use of ECP may allow a significant reduction or even discontinuation of corticosteroids and/or other immunosuppressants, thus leading to reduced long-term morbidity and mortality and improved overall survival. ECP is a well-tolerated therapy. No significant side effects have been reported during the last 30 years. It has been shown that ECP is not associated with an increased incidence of infections, malignancies, or recurrence of underlying malignant disease, neither during short-term nor during long-term therapy.

In vivo study of skin mechanical properties in Raynaud's phenomenon

BACKGROUND/AIM

Raynaud's phenomenon (RP) is usually the first symptom in patients with systemic sclerosis (SS) and may precede skin changes by several months or years. Non-invasive measurements of skin elasticity are very sensitive and appropriate for objective and quantitative evaluation of sclerodermatous skin. The aim of this study was to investigate and compare the mechanical properties of the skin in patients with primary, secondary, and suspected secondary RP.

MATERIALS/METHODS

A total of 63 patients were studied. They were classified as having scleroderma-type nailfold capillary abnormalities--17 with indurative phase of scleroderma (group 1), nine with edematous phase of scleroderma (group 2), 18 with suspected secondary RP (group 3) and as having RP-type nailfold capillary abnormalities, 19 with primary RP (group 4). Thirty-nine sex- and age-matched healthy individuals with normal nailfold capillaroscopy pattern were also studied as controls. Mechanical properties of the skin were evaluated using a non-invasive suction device (Cutometer) equipped with a 2 mm probe. Measurements were performed over five anatomic regions: cheeks, volar forearms, wrists, hands, and proximal phalanx of the fingers. The skin mechanical parameters analyzed were distensibility (Uf), elasticity (Ua/Uf) and viscoelasticity (Uv/Ue).

RESULTS

Most demonstrative changes were observed over volar forearms. Patients included in groups 1-3 were characterized by significantly lower Uf and higher Uv/Ue compared with patient group 4 and controls. Patient groups 1 and 2 showed significantly lower Ua/Uf, as well. There were no significant differences in skin mechanical parameters between patient group 4 and control group.

CONCLUSION

Mechanical properties of the skin in patients with suspected secondary RP significantly differ from these in patients with primary RP and resemble those in patients with edematous phase of scleroderma. Our findings suggest that the non-invasive measurements of skin elasticity could be helpful in identifying patients with RP at risk of developing SS.

A randomized, double-blind, placebo-controlled trial of photopheresis in systemic sclerosis

BACKGROUND

Systemic sclerosis is a multisystemic connective tissue disease with marked involvement of the skin and joints for which few effective evidence based therapies are available. To further investigate the efficacy of extracorporeal photochemotherapy on early aggressive cutaneous disease, a randomized, double-blind, placebo-controlled trial was performed.

OBJECTIVE

Our aim was to evaluate the efficacy of photopheresis in the treatment of patients with systemic sclerosis (scleroderma).

METHODS

This randomized, double-blind, placebo-controlled clinical trial was conducted at 16 investigational sites in the United States, Canada, and Europe. Sixty-four patients with typical clinical and histologic findings of scleroderma, of less than 2 years' duration, were studied. Patients did not receive any other concomitant treatment for scleroderma. Patients were randomized to receive either active or sham photopheresis treatment on two consecutive days monthly for 12 months. Severity of skin (skin scores assessed in 22 body regions) and joint involvement (60 joints examined for contractures) were assessed on a monthly basis.

RESULTS

A statistically significant improvement in skin scores as compared with baseline was observed at 6 months (P = .0024) and 12 months (P = .008) among those who received active photopheresis, but not among those who received sham photopheresis. Comparison of skin scores between the two study arms did not achieve statistical significance because of the small sample size of the study arms. Joint involvement was also significantly improved after 6 months (P = .002) and 12 months (P = .001) of active photopheresis when compared with baseline.

LIMITATIONS

The study lacks sufficient statistical power to reveal a significant difference in skin and joint manifestations between the active and sham photopheresis arms.

CONCLUSION

Photopheresis induced significant improvement of skin and joint involvement in patients with scleroderma of recent onset; however, any effect when compared with sham treatment and a possible placebo effect may be modest.

Collagen turnover is diminished by different clones of skin fibroblasts from early- but not late-stage systemic sclerosis

To investigate collagen turnover and proliferation in dermal fibroblasts from patients with systemic sclerosis (SSc) and their relationship with disease duration and cellular subpopulations, SSc patients were grouped by disease duration (less than 2.5 years or more than 7 years). Control and SSc fibroblasts were obtained from skin biopsies. Collagen biosynthesis was determined by [14C]-proline uptake. Type I/III collagens, gelatinolytic activity, and tissue inhibitors of metalloproteinases (TIMP)-1 and -2 were evaluated by electrophoresis, zymography, and enzyme-linked immunosorbent assay, respectively. Total collagen synthesis and the levels of alpha1(I), alpha2(I), and alpha1(III) chains, as well as TIMP-1 and proliferation were increased in fibroblasts only from patients with early-stage SSc. Gelatinolytic activity did not vary among the groups. This metabolic condition favors a higher local fibroblast population and is characterized by a heterogeneous clonal response in which the majority exhibited higher levels of collagen and TIMP-1 synthesis as well as an increase in their proliferation patterns involving hyper-reactive fibroblast subsets.

T cell clonality and the effect of photopheresis in systemic sclerosis and graft versus host disease

Photopheresis, a leukapheresis-based therapy that combines 8-methoxypsoralen (8-MOP) and ultraviolet-A irradiation, has been shown to be an effective treatment for advanced cutaneous T cell lymphoma (CTCL), but also appears to be effective in certain patients with systemic sclerosis (SSc) and chronic graft versus host disease (cGVHD). In CTCL, clinical responsiveness to photopheresis has been shown to be dependent on the presence of detectable circulating clonal T cells in peripheral blood. Herein we review recent work from our group demonstrating that circulating clonal populations of T cells are detectable in a subgroup of patients with SSc and cGVHD. Furthermore, we provide initial evidence that the presence of a T cell clone in such patients may be associated with responsiveness to photopheresis.

Chronic idiopathic intestinal pseudo-obstruction in an English bulldog

A case of chronic idiopathic intestinal pseudo-obstruction in an English bulldog is described. The dog was presented with chronic weight loss and vomiting. An intestinal obstruction was suspected based on clinical and radiological findings. A diagnosis of chronic idiopathic intestinal pseudo-obstruction was made on the basis of full thickness intestinal biopsies. The dog was refractory to any antiemetic therapy. Necropsy revealed marked atrophy and fibrosis of the tunica muscularis, together with a mononuclear cell infiltrate extending from the duodenum to the colon. This case was presented with clinical findings consistent with visceral myopathy in humans--namely, atony and dilatation of the whole gut--but the histological findings resembled sclerosis limited to the gastrointestinal tract.

Limited cutaneous systemic sclerosis associated with MPO-ANCA positive renal small vessel vasculitis of the microscopic polyangiitis type

Renal disease in systemic sclerosis may present in various patterns. A 66-year-old woman with a history of longstanding limited cutaneous systemic sclerosis of the CREST syndrome variant presented with a sudden left foot drop and rapidly progressive renal insufficiency associated with mild proteinuria, a nephritic urine sediment, and a urinary output of 900 mL/d. There was no history of intake of D-penicillamine, and there were no signs of malignant arterial hypertension or microangiopathic hemolytic anemia. Renal histology showed a small vessel vasculitis of the microscopic polyangiitis type. Serologic tests showed a marked increase of antineutrophil cytoplasmic antibodies with a perinuclear pattern and an elevated titer of antimyeloperoxidase antibodies. No clinical or laboratory signs of Sjögren's syndrome were present. This clinical report adds new information to the spectrum of renal disease in systemic sclerosis. It discusses the association between systemic sclerosis and small vessel vasculitis of the microscopic polyangiitis type as well as the possible meaning of serologic markers.

Treatment of patients with systemic sclerosis with extracorporeal photochemotherapy (photopheresis)

BACKGROUND

Effective treatment modalities for systemic sclerosis, a life-threatening and disabling disease, are still lacking. Possible efficacy of photopheresis has been reported in several studies. Because of the complexity of the treatment, placebo-controlled trials are difficult to perform.

OBJECTIVE

We investigated the effect of photopheresis on clinical parameters (skin score and internal organ functions), immunologic parameters, and quality of life.

METHODS

Nineteen patients with progressive systemic sclerosis of less than 5 years' duration were randomized into 2 groups. One group (group A) received photopheresis for 1 year, the other group (group B) received no treatment at all. After 1 year the groups switched (crossover design). Photopheresis was performed on 2 consecutive days every 4 weeks; the psoralens were administered parenterally. The main outcome parameter was the skin score after 1 year of treatment compared with that of the control group.

RESULTS

The average skin score improved with 5.4% (standard error [SE], 20. 8%) in group A and deteriorated with 4.5% (SE, 13.8%) in group B (not significant; P =.71). Before crossover, the average increase in skin score was 5.3% (means of entire group). No change was observed in other clinical parameters. Approximately 1 year after crossover, the skin score reversed to what would have been expected with an average increase of 5.3% per year. There was also no effect on immunologic parameters. Quality of life did not change during treatment.

CONCLUSION

We were not able to show that photopheresis, performed as described above, is an effective treatment in systemic sclerosis. The difference in average skin score was statistically and clinically insignificant. Despite the small sample size, we concluded that the magnitude of the observed changes is too small to justify photopheresis as a regular treatment.

Serum xylosyltransferase: a new biochemical marker of the sclerotic process in systemic sclerosis

UDP-D-xylose:proteoglycan core protein beta-D-xylosyltransferase (EC2.4.2.26) is the initial enzyme in the biosynthesis of chondroitin sulfate and dermatan sulfate proteoglycans in fibroblasts and chondrocytes. Secretion of xylosyltransferase into the extracellular space was determined in cultured human dermal fibroblasts. A more than 6-fold accumulation of xylosyltransferase activity in cell culture supernatant was observed (day 1, 0.6 microU per 106 cells; day 9, 4.1 microU per 106 cells); however, intracellular xylosyltransferase activity remained at a constant level (0.4 microU per 106 cells). Exposure of human chondrocytes to colchicine led to a 3-fold decreased level of xylosyltransferase and chondroitin-6-sulfate concentration in cell culture. Specific xylosyltransferase activity and chondroitin-6-sulfate concentration decreased in a concentration-dependent manner and in parallel in culture medium and accumulated 5-fold in cell lysates indicating that xylosyltransferase is secreted simultaneously into the extracellular space with chondroitin sulfate proteoglycans. Xylosyltransferase activities were determined in serum samples of 30 patients with systemic sclerosis. Xylosyltransferase activities in female (mean value 1.28 mU per liter, 90% range 1.10-1.55 mU per liter) and male patients (mean 1.39 mU per liter, 90% range 1.16-1. 57 mU per liter) with systemic sclerosis were significantly increased in comparison with blood donors of a corresponding age. Furthermore, xylosyltransferase activity was correlated with the clinical classification of systemic sclerosis. Female patients with diffuse cutaneous systemic sclerosis showed higher serum xylosyltransferase activities than patients with limited systemic sclerosis. These results confirm that the increase of proteoglycan biosynthesis in sclerotic processes of scleroderma is closely related to an elevated xylosyltransferase activity in blood and demonstrate the validity of xylosyltransferase as an additional diagnostic marker for determination of sclerotic activity in systemic sclerosis.

Coexisting morphoea and granuloma annulare-are the conditions related?

Granuloma annulare and localized morphoea are both well described in the dermatological literature. We now present two patients with both of these diseases, a comorbidity rarely described. A possible pathogenic relationship is discussed.

In vivo study of skin mechanical properties in patients with systemic sclerosis

BACKGROUND

Measurements of skin elasticity are more sensitive than the skin severity score and appropriate for evaluation of sclerodermatous skin.

OBJECTIVE

Our purpose was to investigate the mechanical properties of the skin in patients with systemic sclerosis depending on the stage of the disease.

METHODS

Seventeen patients, 8 with edematous phase and 9 with indurative phase of skin involvement, and 16 healthy subjects were studied. Clinical scoring of skin thickness and measurements of skin elasticity with a noninvasive suction device (Cutometer) were performed over 11 anatomic regions.

RESULTS

Edematous phase was characterized by significantly lower immediate distention (Ue) and final distention (Uf), and higher viscoelastic to elastic ratio (Uv/Ue) of the skin compared with indurative phase, except for the forehead (8 mm probe). The changes in skin mechanical parameters for fingers were identical in both phases. Low values of skin distensibility correlated with severe skin thickness or hidebound skin. Results were influenced by body site and by the diameter of measuring probe used.

CONCLUSION

The noninvasive method applied is suitable for objective and quantitative monitoring of skin involvement in patients with systemic sclerosis.

Psychological adjustment to systemic sclerosis

OBJECTIVE

To examine the role of demographic, disability, appraisal, and coping variables in predicting psychological adjustment in individuals with systemic sclerosis.

METHODS

Two hundred forty-two individuals with systemic sclerosis (SSc; diffuse and limited) were surveyed by mail. Demographics, functional disability, pain, control appraisals, 8 types of coping, and individual psychosocial adjustment were assessed by self-report questionnaires with established reliability and validity.

RESULTS

In regression analysis, 3 coping strategies emerged as significant predictors of adjustment: Wishful Thinking, Blaming Self, and Problem-Focused Coping. Self-reports of disability and control appraisals were also significant predictors. Collectively, 46% of the variance in adjustment was explained by these 5 predictor variables. The strongest predictor of overall adjustment was wishful thinking, explaining 22% of the variance in adjustment.

CONCLUSIONS

Potentially modifiable appraisal and coping variables, along with disease-related disability, appear to play an important role in predicting adjustment to SSc, while demographic variables explained little of the variability in patient adjustment.

Docetaxel (Taxotere) associated scleroderma-like changes of the lower extremities. A report of three cases

BACKGROUND

Docetaxel (Taxotere) is a microtubule-stabilizing agent that is potentially important in chemotherapy for a variety of malignancies.

METHODS

A clinical study of the cutaneous reactions experienced by a group of patients receiving docetaxel chemotherapy was undertaken. Patients were examined before initiation of therapy, before and after each cycle of therapy, and were followed subsequent to the completion of docetaxel chemotherapy.

RESULTS

Three patients developed diffuse lower extremity edema (3-18 kg) and subsequent scleroderma-like changes after receiving multiple cycles of docetaxel therapy. These patients had different underlying malignancies and dissimilar prior therapy. Rheumatoid factor, antinuclear antibodies, anticentromere, and topoisomerase antibodies were not present in any patient. The diffuse lower extremity edema did not resolve with diuretic therapy. Cutaneous biopsies in two patients revealed diffuse sclerosis. One patient had a normal lymphangiogram during the edematous phase. Discontinuation of docetaxel correlated with resolution of edema and softening of the skin.

CONCLUSION

The etiology of the scleroderma-like skin changes is unclear but appears to be either a toxic effect of docetaxel or an effect of polysorbate 80 (Tween 80), the vehicle for docetaxel.

Excess matrix accumulation in scleroderma is caused partly by differential regulation of stromelysin and TIMP-1 synthesis

Scleroderma (systemic sclerosis: SSc) is an autoimmune disorder in which excessive extracellular matrix is deposited in skin and internal organs. Because of the importance of metalloproteinases in the turnover of connective tissue, in this study we have developed a novel procedure which utilises flow cytometry (FACS) to measure the production of stromelysin (MMP-3), gelatinase A (MMP-2), and the proteinase inhibitor TIMP-1, by SSc skin fibroblasts. In the presence of monensin, which prevents the secretion of these matrix proteins, there was a similar intracellular accumulation of gelatinase A in normal and SSc cells. However, whereas stromelysin levels also increased in the normal cells, no net synthesis could be detected in the SSc fibroblasts. In marked contrast, the synthesis of TIMP-1 was 50% greater in the SSc cells than in the normal fibroblasts. Our results thus show unequivocally, for the first time, that cells from SSc patients simultaneously produce less stromelysin but substantially higher amounts of TIMP-1 than do normal dermal fibroblasts, suggesting that abnormalities in the regulation of the matrix enzymes and their inhibitors play an important part in the molecular pathology of SSc.