Histopathologic differentiation between localized and systemic scleroderma

Clinical and Histological Characteristics of Localized Morphea, Generalized Morphea and Systemic Sclerosis: A Comparative Study Aided by Machine Learning

Abstract is missing (Short communication)

Systemic therapy in juvenile localized scleroderma

INTRODUCTION

Juvenile localized scleroderma (JLS) is a rare sclerosing disorder of childhood which can result in permanent morbidity and functional disability, if not effectively treated. Treatment should be started in the inflammatory phase before the development of any complication and/or damage.

AREAS COVERED

In this review, we will discuss how to assess disease activity and damage in JLS, and propose an escalation plan for systemic treatment, according to a treat-to-target concept. We will discuss the definition of inactive disease and how and when to discontinue medications.

EXPERT OPINION

Before starting treatment, it is extremely important to assess baseline disease activity for treatment response to be adequately checked. Moreover, the activity of the extra cutaneous involvement is an important part of the assessment. Patients should be treated in the 'therapeutic window,' before significant fibrosis results. Most patients should receive systemic treatments; in these patients, Methotrexate should be used as the first-line disease-modifying anti-rheumatic drug (DMARD). However, methotrexate intolerance or non-response is an issue, and these patients should be proposed a treatment escalation according to results of latest studies. Future research can develop better prognostic markers to help to guide our decision.

Flap Reconstruction for Treatment of Pediatric Linear Scleroderma

BACKGROUND

Linear scleroderma is a rare connective tissue disease characterized by thickening of the skin due to excess collagen deposit. It is the most frequent type of localized scleroderma in the pediatric population (40%-70%), and it usually affects the extremities and head. Linear scleroderma can cause growth disturbances, extremity length discrepancy, and debilitating joint contractures. The aim of this study was to describe the surgical outcomes of microsurgical flap reconstruction of linear scleroderma in the pediatric population.

METHODS

A retrospective review of all children with linear scleroderma was performed at our institution. Patients less than 18 years of age with clinical diagnosis of linear scleroderma and who underwent microsurgical flap reconstruction for correction of their scleroderma were included. Fat grafting procedures were excluded. Patient demographics and surgical outcomes were collected.

RESULTS

A total 7 patients underwent microsurgical flap reconstruction for treatment of their linear scleroderma producing debilitating soft tissue contractures and preventing ambulation or elbow extension. Six patients had scleroderma involving the lower extremity and 1 involving the upper extremity. Three anterolateral thigh and 4 latissimus dorsi flaps were performed. The median age at surgery was 7 years (Q1-Q3, 5-11), and the median body mass index was 21.3 kg/m2 (Q1-Q3, 16.5-22.1). The median follow-up was 121.1 months (Q1-Q3, 43.2-187.4). All flaps survived, and no donor site complications were reported. Perioperative complications included wound infection that required debridement (n = 1), immediate postoperative bleeding requiring surgical intervention (n = 1), intraoperative venous congestion (n = 1), and scleroderma recurrence outside the flap (n = 2). When comparing anterolateral thigh and latissimus dorsi flaps, there was no statistically significant difference in the development of surgical complications, number of surgical revisions per patient [median, 4 (Q1-Q3, 4-7) vs 2.5 (Q1-Q3, 1.3, 3), P = 0.0916], or unplanned surgical interventions [median, 0 (Q1-Q3, 0-1) vs 1 (Q1-Q3, 0-1), P = 0.7228]. The reconstruction was successful in improving range of motion in 6 patients, 5 of which reached full weight-bearing. However, all patients had residual limb deformity, and 4 had remaining extremity length discrepancy.

CONCLUSIONS

Microsurgical flaps are a good option for functional improvement of severe pediatric linear scleroderma affecting the extremities. However, residual limb deformity is common, and patients are often required to undergo additional surgical revisions.

Connective Tissue Diseases in the Skin: Emerging Concepts and Updates on Molecular and Immune Drivers of Disease

Cutaneous manifestations are common across the spectrum of autoimmune diseases. Connective tissue diseases manifesting in the skin are often difficult to classify and require integration of clinical, histopathologic, and serologic findings. This review focuses on the current understanding of the molecular and immune drivers involved in the pathogenesis of cutaneous lupus erythematosus, dermatomyositis, scleroderma/systemic sclerosis, and mixed connective tissue disease. Recent research advances have led to the emergence of new ancillary tools and useful diagnostic clues of which dermatopathologists should be aware to improve diagnostic accuracy for these diseases.

Transcriptomic Evaluation of Juvenile Localized Scleroderma Skin With Histologic and Clinical Correlation

OBJECTIVE

Juvenile localized scleroderma (LS) is an autoimmune disease of the skin whose pathogenesis is not well understood due to the rarity of the disease. This study was undertaken to determine the skin transcriptome in skin biopsy tissue from children with juvenile LS compared to pediatric healthy controls, with identification of significant molecular targets using RNA sequencing (RNA-Seq). In this study, differentially expressed genes (DEGs) were assessed for correlations with histopathologic and clinical features in children with juvenile LS, and were used to group the children into distinct genetic clusters based on immunophenotype.

METHODS

RNA-Seq was performed on sections of paraffin-embedded skin tissue obtained from 28 children with juvenile LS and 10 pediatric healthy controls. RNA-Seq was carried out using an Illumina HTS TruSeq RNA Access library prep kit, with data aligned using STAR and data analysis using a DESeq2 platform. A standardized histologic scoring system was used to score skin sections for the severity of inflammation and levels of collagen deposition. Histologic scoring was completed by 2 pathologists who were blinded with regard to the status of each sample. Spearman's rank correlation coefficients were used to assess significant correlations between DEG expression profiles and skin histologic findings in patients with juvenile LS.

RESULTS

We identified 589 significant DEGs in children with juvenile LS as compared to healthy controls. Hierarchical clustering was used to demonstrate 3 distinct juvenile LS immunophenotype clusters. The histologic scores of skin inflammation (based on numbers and categories of inflammatory cell infiltrates) were significantly correlated with the expression levels of HLA-DPB1, HLA-DQA2, HLA-DRA, and STAT1 genes (r_s > 0.5, P < 0.01). Collagen thickness correlated with the expression levels of collagen organization genes as well as with genes found to be correlated with the severity of inflammation, including genes for major histocompatibility complex (MHC) class I, MHC class II, and interferon-γ signaling.

CONCLUSION

Among children with juvenile LS, 3 distinct genetic signatures, or clusters, were identified. In one cluster, inflammation-related pathways were up-regulated, corresponding to the histologic skin inflammation score. In the second cluster, fibrosis-related pathways were up-regulated. In the third cluster, gene expression in the skin corresponded to the patterns seen in healthy controls. Up-regulation of HLA class II genes was observed within the first cluster (characterized by predominant inflammation), a feature that has also been observed in the peripheral blood of patients with morphea and in the skin of patients with systemic sclerosis.

Advances in the role of helper T cells in autoimmune diseases

Autoimmune diseases are primary immune diseases in which autoreactive antibodies or sensitized lymphocytes destroy and damage tissue and cellular components, resulting in tissue damage and organ dysfunction. Helper T cells may be involved in the pathogenesis of autoimmune diseases under certain conditions. This review summarizes recent research on the role of helper T cells in autoimmune diseases from two aspects, helper T cell-mediated production of autoantibodies by B cells and helper T cell-induced activation of abnormal lymphocytes, and provides ideas for the treatment of autoimmune diseases. The abnormal expression of helper T cells promotes the differentiation of B cells that produce autoantibodies, which leads to the development of different diseases. Among them, abnormal expression of Th2 cells and T follicular helper cells is more likely to cause antibody-mediated autoimmune diseases. In addition, abnormal activation of helper T cells also mediates autoimmune diseases through the production of abnormal cytokines and chemokines. Helper T cells play an essential role in the pathogenesis of autoimmune diseases, and a full understanding of their role in autoimmune diseases is helpful for providing ideas for the treatment of autoimmune diseases.

Skin Histology in Systemic Sclerosis: a Relevant Clinical Biomarker

PURPOSE OF REVIEW

Systemic sclerosis (SSc) is a life-threatening autoimmune disease that causes debilitating skin fibrosis. The skin in SSc is easily accessible, and skin biopsies may provide rich biological data regarding underlying disease pathophysiology. Here, we review literature relevant to the potential for skin histology to serve as a diagnostic, pharmacokinetic/response, and predictive biomarker in SSc.

RECENT FINDINGS

Multiple histologic parameters correlate with SSc severity, including alpha smooth muscle actin (aSMA), CD34, collagen density, thickness, and inflammatory cell infiltration. Recent clinical trials incorporate skin histology as exploratory outcome measurements; however, a standard approach is not yet established. The possibility that skin histology may be useful as a predictive biomarker was suggested by a recent study that identified genes related to skin aSMA and CD34 staining intensity that were increased at baseline among improvers versus nonimprovers. Current literature supports skin histology as a mechanism to measure treatment response, but future work is needed to define minimally meaningful changes in key SSc skin histologic features.

Clinical characteristics and histopathologic changes of morphea: A single-center, retrospective study of 137 patients

BACKGROUND

The clinicopathologic correlations and prognostic risk factors for refractory disease in morphea (localized scleroderma) are poorly described.

OBJECTIVE

To investigate the association between clinical characteristics and histopathologic features of morphea and identify risk factors for refractory disease.

METHODS

We retrospectively reviewed the clinical and histopathologic features, treatment regimens, and clinical responses for 137 patients with biopsy-proven morphea from January 2008 to May 2019. Multivariate analysis was conducted to identify factors associated with poor treatment response.

RESULTS

We detected associations between the pattern and degree of sclerosis and the anatomic site of the lesion, as well as between severe inflammation and concomitant autoimmune disease. Additionally, both bottom-heavy sclerosis and increased inflammation were associated with functional limitations/clinical symptoms. Based on our multivariate analysis, we found that increased risk of poor treatment response was correlated with tissue eosinophils and basal pigmentation.

LIMITATIONS

This was a single-center retrospective study.

CONCLUSION

Skin biopsy samples could show specific features of morphea, including eosinophil infiltration and basal pigmentation, which may indicate the need for aggressive treatment and frequent monitoring.

A case of Myhre syndrome mimicking juvenile scleroderma

BACKGROUND

Myhre syndrome is a genetic disorder caused by gain of function mutations in the SMAD Family Member 4 (SMAD4) gene, resulting in progressive, proliferative skin and organ fibrosis. Skin thickening and joint contractures are often the main presenting features of the disease and may be mistaken for juvenile scleroderma.

CASE PRESENTATION

We report a case of a 13 year-old female presenting with widespread skin thickening and joint contractures from infancy. She was diagnosed with diffuse cutaneous systemic sclerosis, and treatment with corticosteroids and subcutaneous methotrexate recommended. There was however disease progression prompting genetic testing. This identified a rare heterozygous pathogenic variant c.1499 T > C (p.Ile500Thr) in the SMAD4 gene, suggesting a diagnosis of Myhre syndrome. Securing a molecular diagnosis in this case allowed the cessation of immunosuppression, thus reducing the burden of unnecessary and potentially harmful treatment, and allowing genetic counselling.

CONCLUSION

Myhre Syndrome is a rare genetic mimic of scleroderma that should be considered alongside several other monogenic diseases presenting with pathological fibrosis from early in life. We highlight this case to provide an overview of these genetic mimics of scleroderma, and highlight the molecular pathways that can lead to pathological fibrosis. This may provide clues to the pathogenesis of sporadic juvenile scleroderma, and could suggest novel therapeutic targets.

Histopathologic Spectrum of Morphea

ABSTRACT

Morphea is an autoimmune skin disease with protean clinical manifestations. Histologic features are similarly variable, and skin biopsies may be nondiagnostic. A single-institution retrospective cohort study was conducted. Morphea patients who had a biopsy in 2005-2015 were included, and a histopathological review was conducted by 2 pathologists. There were 51 biopsy specimens from 40 subjects. The most common histologic features were dermal sclerosis (90%), dermal thickening (78%), collagen homogenization (86%), a superficial and deep infiltrate (76%), a moderate-abundant inflammatory infiltrate (73%), and periadnexal fat loss/decreased skin appendages (71%). Twenty-four specimens were not diagnostic of morphea. In these specimens, the main clues to diagnosis included the presence of dermal sclerosis (79%), subtle collagen homogenization (75%), dermal thickening (58%), moderate-to-abundant plasma cells (50%), and perineural inflammation (50%). There were no statistically significant differences between active and inactive lesions, nor untreated and treated lesions. The histopathologic features of morphea are variable and a high proportion of biopsies are not diagnostic. Clinicians and pathologists should have a high degree of suspicion to correctly make the diagnosis of morphea.

Overview of Juvenile localized scleroderma and its management

BACKGROUND

Juvenile localized scleroderma (JLS) is a rare pediatric disease characterized by inflammation and skin thickening. JLS is associated with deep tissue and extracutaneous involvement that often results in functional impairment and growth disturbances. This article provides an overview of the disease with a focus on active features and treatment.

DATA SOURCES

We searched databases including PubMed, Elsevier and MedLine and Wanfang, reviewing publications from 2013 to 2019. Selected earlier publications were also reviewed.

RESULTS

Linear scleroderma is the most common JLS subtype. Several lines of evidence suggest that JLS is an autoimmune disease. Extracutaneous involvement is common and can present before the onset of skin disease. Multiple skin features are associated with disease activity, and activity can also manifest as arthritis, myositis, uveitis, seizures, and growth impairment. Systemic immunosuppressive treatment, commonly methotrexate with or without glucocorticoids, greatly improves outcome and is recommended for treating JLS patients with active disease and moderate or higher severity. Long term monitoring is needed because of the disease's chronicity and the high frequency of relapses off of treatment.

CONCLUSIONS

JLS is associated with a risk for disabling and disfiguring morbidity for the growing child. Identifying active disease is important for guiding treatment, but often difficult because of the paucity of markers and lack of a universal skin activity feature. More studies of JLS pathophysiology are needed to allow the identification of biomarkers and therapeutic targets. Comparative effectiveness treatment studies are also needed to work towards optimizing care and outcome.

Immunopathogenesis of Juvenile Systemic Sclerosis

Juvenile-onset systemic sclerosis (jSSc) is a rare and severe autoimmune disease with associated life-threatening organ inflammation and evidence of fibrosis. The organ manifestations of jSSc resemble adult SSc, but with better outcomes and survival. The etiology of jSSc appears to reflect adult-onset SSc, with similar inflammatory mediators and autoantibodies, but with a significant population of children with uncharacterized anti-nuclear antibodies. The genetics of patients with jSSc differ from women with SSc, resembling instead the genes of adult males with SSc, with additional HLA genes uniquely associated with childhood-onset disease. Current treatments are aimed at inhibiting the inflammatory aspect of disease, but important mechanisms of fibrosis regulated by dermal white adipose tissue dendritic cells may provide an avenue for targeting and potentially reversing the fibrotic stage.

Scleroderma in Children and Adolescents: Localized Scleroderma and Systemic Sclerosis

Scleroderma is a rare disease that has two main forms: localized scleroderma (LS) and systemic sclerosis (SSc). Both are chronic diseases, can present in different patterns (subtypes), and are associated with extracutaneous involvement in pediatric patients. Morbidity and mortality is much worse for juvenile SSc with patients at risk for life-threatening lung, heart, and other visceral organ fibrosis and vasculopathy. Mortality is extremely rare in juvenile LS, but morbidity is common, with patients at risk for severe disfigurement and functional impairment. Scleroderma treatment is directed towards controlling inflammation and managing specific problems. Early diagnosis can greatly improve outcome.

Morphea and Eosinophilic Fasciitis: An Update

Morphea, also known as localized scleroderma, encompasses a group of idiopathic sclerotic skin diseases. The spectrum ranges from relatively mild phenotypes, which generally cause few problems besides local discomfort and visible disfigurement, to subtypes with severe complications such as joint contractures and limb length discrepancies. Eosinophilic fasciitis (EF, Shulman syndrome) is often regarded as belonging to the severe end of the morphea spectrum. The exact driving mechanisms behind morphea and EF pathogenesis remain to be elucidated. However, extensive extracellular matrix formation and autoimmune dysfunction are thought to be key pathogenic processes. Likewise, these processes are considered essential in systemic sclerosis (SSc) pathogenesis. In addition, similarities in clinical presentation between morphea and SSc have led to many theories about their relatedness. Importantly, morphea may be differentiated from SSc based on absence of sclerodactyly, Raynaud’s phenomenon, and nailfold capillary changes. The diagnosis of morphea is often based on characteristic clinical findings. Histopathological evaluation of skin biopsies and laboratory tests are not necessary in the majority of morphea cases. However, full-thickness skin biopsies, containing fascia and muscle tissue, are required for the diagnosis of EF. Monitoring of disease activity and damage, especially of subcutaneous involvement, is one of the most challenging aspects of morphea care. Therefore, data harmonization is crucial for optimizing standard care and for comparability of study results. Recently, the localized scleroderma cutaneous assessment tool (LoSCAT) has been developed and validated for morphea. The LoSCAT is currently the most widely reported outcome measure for morphea. Care providers should take disease subtype, degree of activity, depth of involvement, and quality-of-life impairments into account when initiating treatment. In most patients with circumscribed superficial subtypes, treatment with topical therapies suffices. In more widespread disease, UVA1 phototherapy or systemic treatment with methotrexate (MTX), with or without a systemic corticosteroid combination, should be initiated. Disappointingly, few alternatives for MTX have been described and additional research is still needed to optimize treatment for these debilitating conditions. In this review, we present a state-of-the-art flow chart that guides care providers in the treatment of morphea and EF.

Histopathological changes in morphea and their clinical correlates: Results from the Morphea in Adults and Children Cohort V

BACKGROUND

Histopathological features in morphea (localized scleroderma) and their clinical correlates are poorly described.

OBJECTIVE

We sought to systematically describe histologic changes of morphea in a large, well-annotated cohort and determine the association between histopathology and clinical features.

METHODS

This was a cross-sectional study of 83 patients enrolled in the Morphea in Adults and Children cohort. The main outcome measure was the association of microanatomical location and degree of sclerosis and inflammation seen on histologic samples with patient-reported symptoms and physician-based measures of severity.

RESULTS

Pattern of sclerosis was associated with morphea subtype, the presence of patient-reported symptoms, and functional limitation. A bottom-heavy pattern of sclerosis was associated with pain and tightness (P = .0039 and .001, respectively). These symptoms were not associated with a top-heavy pattern. Severe inflammation may be associated with pain and functional limitation (P = .073 for both).

LIMITATIONS

Small sample size limits ability to detect associations, particularly in subgroups.

CONCLUSIONS

Histopathological examination of morphea may assist in identifying patients who may require additional monitoring and treatment. Features such as patterns of sclerosis and severity of inflammation should be included in pathology reports to help aid in clinical management.

Multiplex assessment of serum cytokine and chemokine levels in idiopathic morphea and vitamin K1-induced morphea

The levels of 63 cytokines, chemokines, and growth factors were measured in the serum of four patients with idiopathic morphea and of one patient with vitamin K₁-induced morphea employing a multiplex assay to identify the role of inflammatory/immunologic events in their pathogenesis. Full-thickness skin biopsies of affected skin were analyzed by histopathology. Luminex assays for 63 cytokines, chemokines, and growth factors were performed in the sera from four patients with idiopathic morphea and in two different samples of serum obtained in two separate occasions from one patient with vitamin K₁-induced morphea. The serum values of numerous inflammatory cytokines and growth factors including IL-2, IL-4, IL-6, and IFNβ were markedly increased in the serum of patients with idiopathic morphea, whereas, these values were normal in the serum of the patient with vitamin K₁-induced morphea. In contrast, serum eotaxin levels were greater than threefold higher in the patient with vitamin K₁-induced morphea compared to patients with idiopathic morphea. The results demonstrated remarkable increases in the levels of numerous cytokines and chemokines in the serum samples of all patients with idiopathic morphea indicative of a prominent role of inflammatory/immunologic events in its pathogenesis. The results also showed statistically significant differences between idiopathic morphea and vitamin K₁-induced morphea suggesting that their development involves different pathogenetic mechanisms.

Localized scleroderma: a review

Localized scleroderma (LoS) comprises a heterogeneous spectrum of fibrotic diseases that primarily affect the skin with inflammation and skin thickening. The extent of skin involvement and manifestation at extra-cutaneous structures characterizes the specific subset. Fat tissue, fascia, and sometimes muscle, and bones might be involved, and in rare cases the central nervous or ocular system.

A worldwide accepted classification system for LoS is still lacking. The latest guidelines have proposed a distinction of limited, generalized, linear, deep, and mixed types. The exact pathophysiology of LoS is not fully understood yet, but it is thought that an externally triggered release of pro-inflammatory cytokines leads to a dysregulation of the connective tissue metabolism.

LoS is diagnosed according to typical clinical features. Further diagnostic procedures are helpful to characterize the subtype and to define the extent of inflammation and fibrosis.

Due to the heterogeneity of LoS, therapeutic strategies should always be selected depending on the respective subtype. The stage of tissue inflammation and sclerosis has to be considered. Treatment options such as topical corticosteroids, calcipotriol, and calcineurin inhibitors as well as phototherapy are well established. In subsets with severe wide-spread skin manifestation and/or extra-cutaneous involvement, methotrexate monotherapy or a combination of methotrexate and systemic corticosteroids need to be considered. Physical treatment should always be added to the topical and systemic treatment to prevent significant disabilities due to LoS. This article provides an updated review on the epidemiology, pathophysiology, clinical classification and treatment options for patients suffering from LoS.

Peripheral blood cytokine and chemokine profiles in juvenile localized scleroderma: T-helper cell-associated cytokine profiles

OBJECTIVE

To evaluate peripheral blood T-helper (TH) cell-associated cytokine and chemokine profiles in localized scleroderma (LS), and correlate them with clinical disease features, including disease activity parameters.

METHODS

A 29-plex Luminex platform was used to analyze the humoral profile of plasma samples from 69 pediatric LS patients and 71 healthy pediatric controls. Cytokine/chemokine levels were compared between these two groups and within LS patients, focusing on validated clinical outcome measures of disease activity and damage in LS.

RESULTS

Plasma levels of IP-10, MCP-1, IL-17a, IL-12p70, GM-CSF, PDGF-bb, IFN-α2, and IFN-γ were significantly higher in LS subjects compared to healthy controls. Analysis within the LS group demonstrated IP-10, TNF-α, and GM-CSF correlated with clinical measures of disease activity. Several cytokines/chemokines correlated with anti-histone antibody, while only a few correlated with positive ANA and single-stranded DNA antibody.

CONCLUSION

This is the first time that multiple cytokines and chemokines have been examined simultaneously in LS. In general, a TH1 (IFN-γ) and TH17 (IL-17a) predominance was demonstrated in LS compared to healthy controls. There is also an IFN-γ signature with elevated IP-10, MCP-1, and IFN-γ, which has been previously demonstrated in systemic sclerosis, suggesting a shared pathophysiology. Within the LS patients, those with active disease demonstrated IP-10, TNF-α, and GM-CSF, which may potentially serve as biomarkers of disease activity in the clinical setting.

Management of Systemic Sclerosis-Related Skin Disease: A Review of Existing and Experimental Therapeutic Approaches

The skin is the most common organ system involved in patients with systemic sclerosis (SSc). Nearly all patients experience cutaneous symptoms, including sclerosis, Raynaud's phenomenon, digital ulcers, telangiectasias, and calcinosis. In addition to posing functional challenges, cutaneous symptoms are often a major cause of pain, psychological distress, and body image dissatisfaction. The present article reviews the main features of SSc-related cutaneous manifestations and highlights an evidence-based treatment approach for treating each manifestation. This article also describes novel treatment approaches and opportunities for further research in managing this important clinical dimension of SSc.

Major histocompatibility complex class I and class II alleles may confer susceptibility to or protection against morphea: findings from the Morphea in Adults and Children cohort

OBJECTIVE

To determine the HLA class I and class II alleles of the human major histocompatibility complex showing an association with morphea (localized scleroderma) in the Morphea in Adults and Children (MAC) cohort, using a nested case-control association study.

METHODS

Patients with morphea were identified from the MAC cohort, and matched controls were obtained from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases Scleroderma Family Registry and DNA Repository and from the Division of Rheumatology at the University of Texas Health Science Center at Houston. HLA class II genotyping and single-strand conformational polymorphism typing were performed to identify HLA-A, B, and C alleles. Associations between HLA class I and class II alleles and morphea, as well as its subphenotypes, were determined.

RESULTS

Two hundred eleven patients with morphea and 726 matched controls were available for HLA class I typing, and 158 patients with morphea and 1,008 matched controls were available for HLA class II typing. The strongest associations were found with DRB1*04:04 (odds ratio [OR] 2.3, 95% confidence interval [95% CI] 1.4-4.0, P = 0.002), and HLA-B*37 conferred the highest OR among the class I alleles (OR 3.2, 95% CI 1.5-6.5, P = 0.001). Comparison of the risk allele profile in this cohort with the risk alleles previously identified in patients with systemic sclerosis, determined using the same methods and same control population, revealed one allele in common, DRB*04:04.

CONCLUSION

These results demonstrate that specific HLA class I and class II alleles are associated with morphea and are also likely to be associated with generalized and linear subtypes of morphea. The morphea-associated alleles are different from those found in scleroderma, suggesting that morphea is immunogenetically distinct. Risk alleles in morphea are also associated with conditions such as rheumatoid arthritis (RA) and other autoimmune conditions. Population-based studies have indicated that patients with RA have an increased risk of morphea, and therefore a common susceptibility allele may be implicated.

High IL-17E and low IL-17C dermal expression identifies a fibrosis-specific motif common to morphea and systemic sclerosis

BACKGROUND

High interleukin (IL)-17A levels are characteristically found in the skin of systemic sclerosis (SSc) individuals. Our aim was to investigate whether the dermal expression of IL-17A and related IL-17 family members (i.e. IL-17C, IL-17E and IL-17F) could distinguish fibrotic from healthy skin and could show similarities in SSc and morphea, two disorders with presumed distinct pathogenesis, but characterized by skin fibrosis.

METHODS

Biopsies were obtained from the involved skin of 14 SSc, 5 morphea and 8 healthy donors (HD) undergoing plastic surgery. Immunohistochemistry/immunofluorescence techniques were coupled to a semi-automated imaging quantification approach to determine the presence of the IL-17 family members in the skin. The in vitro effects induced by the IL-17 family members on fibroblasts from normal and SSc individuals were assessed by ELISA and RIA.

RESULTS

Positive cells for each of the IL-17 isoforms investigated were present in the dermis of all the individuals tested, though with variable frequencies. SSc individuals had increased frequency of IL-17A+ (p = 0.0237) and decreased frequency of IL-17F+ (p = 0.0127) and IL-17C+ cells (p = 0.0008) when compared to HD. Similarly, morphea individuals had less frequent IL-17C+ cells (p = 0.0186) in their skin but showed similar number of IL-17A+ and IL-17F+ cells when compared to HD. Finally, IL-17E+ cells were more numerous in morphea (p = 0.0109) and tended to be more frequent in SSc than in HD. Fibroblast production of IL-6, MMP-1 and MCP-1 was enhanced in a dose-dependent manner in the presence of IL-17E and IL-17F, but not in the presence of IL-17C. None of the cytokine tested had significant effect on type I collagen production. Of interest, in SSc the frequency of both IL-17A and IL-17F positive cells increased with disease duration.

CONCLUSIONS

The frequency of IL-17A and IL-17F distinguish SSc to morphea individuals while dermal expression of IL-17C (low) and IL-17E (high) identifies a fibrosis-specific motif. The specific IL-17C/IL-17E cytokine combination may thus play a role in the development of fibrosis.

Fibrosing connective tissue disorders of the skin: molecular similarities and distinctions

A variety of fibrosing connective tissue disorders of the skin have been described. They all share a characteristic activation of fibroblasts resulting in excessive production and deposition of extracellular matrix whereas their etiologies, incidence rates and clinical appearances differ dramatically in part. As effective treatment options are still not on hand, the understanding of cutaneous fibrogenesis needs to be improved. This review focuses on the molecular differences and similarities of the major fibrosing skin disorders namely systemic sclerosis, localized scleroderma, keloid and hypertrophic scars, Eosinophilic fasciitis, Lichen sclerosus and graft-versus-host-disease. Abnormalities in ECM turnover and the impact of matrix-metalloproteases were closely examined. It could be concluded, that besides increased collagen synthesis, modified ECM degradation is an as important factor in cutaneous fibrogenesis. The influence of immune components such as HLA haplotypes and the production of auto-antibodies is crucial for some of the diseases, but not decisive for skin fibrosis in general. A great number of cytokines was reported to be differentially regulated in the respective disorders among whom the components of the gp130/STAT3 signaling pathway seem to be of pivotal importance. Furthermore, the role of miRNAs in the pathogenesis of fibrosing connective tissue diseases of the skin was analyzed according to the current state of knowledge. In summary, this review gives an explicit overview of the various molecular mechanisms leading to fibrosis in the skin and the underlying connective tissue and reveals the most promising targets for future therapeutic approaches.

Pediatric scleroderma: systemic or localized forms

Pediatric scleroderma includes 2 major groups of clinical entities, systemic sclerosis (SSc) and localized scleroderma (LS). Although both share a common pathophysiology, their clinical manifestations differ. LS is typically confined to the skin and underlying subcutis, with up to a quarter of patients showing extracutaneous disease manifestations such as arthritis and uveitis. Vascular, cutaneous, gastrointestinal, pulmonary, and musculoskeletal involvement are most commonly seen in children with SSc. Treatment of both forms targets the active inflammatory stage and halts disease progression; however, progress needs to be made toward the development of more effective antifibrotic therapy to help reverse disease damage.

Cytokine profiles in localized scleroderma and relationship to clinical features

Localized scleroderma (LS) is a disfiguring autoimmune disease of the skin and underlying tissue that mainly affects the pediatric population. Inflammation of the tissue leads to fibrosis and atrophy, causing physical and psychological disability that can continue throughout childhood into adulthood. Available therapies for LS have had variable effects and are associated with morbidity themselves. A better understanding of the pathophysiology of LS, especially during the active inflammatory phase, would lead to more directed and efficacious therapies. As in systemic sclerosis (SSc), the other form of scleroderma, T-helper (Th) cells and their associated cytokines have been suggested to contribute significantly to the pathophysiology of LS supported by the presence of cytokines from these lineages in the sera and tissue of LS patients. It is postulated that the imbalance between Th1/Th2/Th17 cell subsets drives inflammation in the early stages of disease (Th1 and Th17 predominant) and fibrosis in the later stages of scleroderma (Th2 predominant). We review the available experimental data regarding cytokines in LS and compare them to available clinical disease severity and activity features. This provides the platform to launch further investigations into the role of select cytokines in the pathogenesis of LS and to provide directed therapeutic options in the future.

The pathogenesis of systemic sclerosis

Systemic sclerosis (SSc), also known as scleroderma, is a rare connective tissue disease characterized by vascular and immune dysfunction, leading to fibrosis that can damage multiple organs. Its pathogenesis is complex and poorly understood. Two major clinical subtypes are the limited and diffuse forms. Research into SSc has been hampered by its rarity, its clinical heterogeneity, and the lack of mouse models that accurately recapitulate the disease. Clinical and basic studies have yielded some mechanistic clues regarding pathogenesis. Recent insights gained through the use of microarrays have revealed distinctive subsets of SSc within and beyond the limited and diffuse subsets. In this review, we discuss potential mechanisms underlying the vascular, autoimmune, and fibrotic points of dysregulation. Proper categorization of SSc patients for research studies by use of microarrays or other biomarkers is critical, as disease heterogeneity may explain some of the inconsistencies of prior studies.

Histopathological cutaneous alterations in systemic sclerosis: a clinicopathological study

Introduction

The aims of the present study were to identify histopathological parameters which are linked to local clinical skin disease at two distinct anatomical sites in systemic sclerosis (SSc) patients with skin involvement (limited cutaneous systemic sclerosis (lcSSc) or diffuse cutaneous systemic sclerosis (dcSSc)) and to determine the sensitivity of SSc specific histological alterations, focusing on SSc patients without clinical skin involvement (limited SSc (lSSc)).

Methods

Histopathological alterations were systematically scored in skin biopsies of 53 consecutive SSc patients (dorsal forearm and upper inner arm) and 18 controls (upper inner arm). Clinical skin involvement was evaluated using the modified Rodnan skin score. In patients with lcSSc or dcSSc, associations of histopathological parameters with local clinical skin involvement were determined by generalised estimation equation modelling.

Results

The hyalinised collagen score, the myofibroblast score, the mean epidermal thickness, the mononuclear cellular infiltration and the frequency of focal exocytosis differed significantly between biopsies with and without local clinical skin involvement. Except for mononuclear cellular infiltration, all of the continuous parameters correlated with the local clinical skin score at the dorsal forearm. Parakeratosis, myofibroblasts and intima proliferation were present in a minority of the SSc biopsies, but not in controls. No differences were found between lSSc and controls.

Conclusions

Several histopathological parameters are linked to local clinical skin disease. SSc-specific histological alterations have a low diagnostic sensitivity.

Fibrillin assemblies: extracellular determinants of tissue formation and fibrosis

The extracellular matrix (ECM) plays a key role in tissue formation, homeostasis and repair, mutations in ECM components have catastrophic consequences for organ function and therefore, for the fitness and survival of the organism. Collagen, fibrillin and elastin polymers represent the architectural scaffolds that impart specific mechanic properties to tissues and organs. Fibrillin assemblies (microfibrils) have the additional function of distributing, concentrating and modulating local transforming growth factor (TGF)-β and bone morphogenetic protein (BMP) signals that regulate a plethora of cellular activities, including ECM formation and remodeling. Fibrillins also contain binding sites for integrin receptors, which induce adaptive responses to changes in the extracellular microenvironment by reorganizing the cytoskeleton, controlling gene expression, and releasing and activating matrix-bound latent TGF-β complexes. Genetic evidence has indicated that fibrillin-1 and fibrillin-2 contribute differently to the organization and structural properties of non-collagenous architectural scaffolds, which in turn translate into discrete regulatory outcomes of locally released TGF-β and BMP signals. Additionally, the study of congenital dysfunctions of fibrillin-1 has yielded insights into the pathogenesis of acquired connective tissue disorders of the connective tissue, such as scleroderma. On the one hand, mutations that affect the structure or expression of fibrillin-1 perturb microfibril biogenesis, stimulate improper latent TGF-β activation, and give rise to the pleiotropic manifestations in Marfan syndrome (MFS). On the other hand, mutations located around the integrin-binding site of fibrillin-1 perturb cell matrix interactions, architectural matrix assembly and extracellular distribution of latent TGF-β complexes, and lead to the highly restricted fibrotic phenotype of Stiff Skin syndrome. Understanding the molecular similarities and differences between congenital and acquired forms of skin fibrosis may therefore provide new therapeutic tools to mitigate or even prevent disease progression in scleroderma and perhaps other fibrotic conditions.

Development and initial validation of the localized scleroderma skin damage index and physician global assessment of disease damage: a proof-of-concept study

OBJECTIVE

To develop and assess the psychometric properties of the Localized Scleroderma (LS) Skin Damage Index (LoSDI) and Physician Global Assessment of disease Damage (PGA-D).

METHODS

Damage was defined as irreversible/persistent changes (>6 months) due to previous active disease/complications of therapy. Eight rheumatologists assessed the importance of 17 variables in formulating the PGA-D/LoSDI. LS patients were evaluated by two rheumatologists using both tools to assess their psychometric properties. LoSDI was calculated by summing three scores for cutaneous features of damage [dermal atrophy (DAT), subcutaneous atrophy (SAT) and dyspigmentation (DP)] measured at 18 anatomic sites. Patient GA of disease severity (PtGA-S), Children's Dermatology Life Quality Index (CDLQI) and PGA-D were recorded at the time of each examination.

RESULTS

Thirty LS patients (112 lesions) and nine patient-visit pairs (18 lesions) were included for inter- and intra-rater reliability study. LoSDI and its domains DAT, SAT, DP and PGA-D demonstrated excellent inter- and intra-rater reliability (reliability coefficients 0.86-0.99 and 0.74-0.96, respectively). LoSDI correlated moderately with PGA-D and poorly with PtGA-S and CDLQI. PGA-D correlated moderately with PtGA-S, but poorly with CDLQI.

CONCLUSIONS

To complete the LS Cutaneous Assessment Tool (LoSCAT), we developed and evaluated the psychometric properties of the LoSDI and PGA-D in addition to the LS Skin Severity Index (LoSSI). These instruments will facilitate evaluation of LS patients for individual patient management and clinical trials. LoSDI and PGA-D demonstrated excellent reliability and high validity. LoSCAT provides an improved understanding of LS natural history. Further study in a larger group of patients is needed to confirm these preliminary findings.

The localized scleroderma skin severity index and physician global assessment of disease activity: a work in progress toward development of localized scleroderma outcome measures

OBJECTIVE

To develop and evaluate a Localized Scleroderma (LS) Skin Severity Index (LoSSI) and global assessments' clinimetric property and effect on quality of life (QOL).

METHODS

A 3-phase study was conducted. The first phase involved 15 patients with LS and 14 examiners who assessed LoSSI [surface area (SA), erythema (ER), skin thickness (ST), and new lesion/extension (N/E)] twice for inter/intrarater reliability. Patient global assessment of disease severity (PtGA-S) and Children's Dermatology Life Quality Index (CDLQI) were collected for intrarater reliability evaluation. The second phase was aimed to develop clinical determinants for physician global assessment of disease activity (PhysGA-A) and to assess its content validity. The third phase involved 2 examiners assessing LoSSI and PhysGA-A on 27 patients. Effect of training on improving reliability/validity and sensitivity to change of the LoSSI and PhysGA-A was determined.

RESULTS

Interrater reliability was excellent for ER [intraclass correlation coefficient (ICC) 0.71], ST (ICC 0.70), LoSSI (ICC 0.80), and PhysGA-A (ICC 0.90) but poor for SA (ICC 0.35); thus, LoSSI was modified to mLoSSI. Examiners' experience did not affect the scores, but training/practice improved reliability. Intrarater reliability was excellent for ER, ST, and LoSSI (Spearman's rho = 0.71-0.89) and moderate for SA. PtGA-S and CDLQI showed good intrarater agreement (ICC 0.63 and 0.80). mLoSSI correlated moderately with PhysGA-A and PtGA-S. Both mLoSSI and PhysGA-A were sensitive to change following therapy.

CONCLUSION

mLoSSI and PhysGA-A are reliable and valid tools for assessing LS disease severity and show high sensitivity to detect change over time. These tools are feasible for use in routine clinical practice. They should be considered for inclusion in a core set of LS outcome measures for clinical trials.

Skin disease: a cardinal feature of systemic sclerosis

Despite the heterogeneity of SSc, almost all patients have skin involvement. As such, skin manifestations are critical in the initial diagnosis of SSc and in the subsequent sub-classification into the different subsets of disease. The two principal subsets are lcSSc and dcSSc. The main difference between these two subsets is the speed of disease progression and the extent and severity of skin and visceral involvement; lcSSc has an insidious onset with skin involvement confined largely to the face and extremities. Whilst vascular manifestations of SSc such as pulmonary arterial hypertension are typically more common in lcSSc, patients in both subsets can develop ischaemic digital ulcers. In dcSSc, disease progression is very rapid, with skin thickening extending beyond the extremities and earlier, more widespread internal organ involvement. DcSSc is generally considered to be the more severe subset of the disease. Skin scores in SSc correlate inversely with survival and are considered a valuable marker of disease severity. Skin involvement is easily detectable and, using the modified Rodnan skin score, the degree of skin fibrosis can be quantified. As well as general management measures, a number of targeted therapies are commonly used for treatment of cutaneous manifestations of SSc. These include the intravenous prostanoid iloprost and the dual endothelin receptor antagonist bosentan, which is approved in Europe for the prevention of new digital ulcers.

Clinical and histological findings in nephrogenic systemic fibrosis

Nephrogenic systemic fibrosis (NSF) is a relative newcomer to the world of medicine. NSF was introduced just over 10 years ago as nephrogenic fibrosing dermopathy, but with further investigation, its systemic nature was determined. The strict adherence to a definition requiring both clinical and pathological concordance has allowed for careful separation of this entity from other fibrosing disorders, leading eventually to the realization that gadolinium-based contrast agents were closely associated with its onset. As planned prospective studies get underway, it is of paramount importance that researchers and clinicians realize that NSF remains a very challenging diagnosis, and that both clinical and histopathological criteria must be employed to reach the most accurate diagnosis possible.

Sclérodermies localisées ou morphées

DEFINITION AND FREQUENCY: Localized scleroderma, also known as morphea, is a sclerotic condition limited to the skin. The specific clinical entity depends on the extent, linear disposition and depth of the lesions. Morphea is ten times more prevalent than systemic sclerosis, and its prognosis is generally good: superficial forms resolve within 3 years.

NO SYSTEMIC INVOLVEMENT

In the absence of symptoms, examinations to detect systemic involvement are purposeless. Plaque morphea is the most frequent clinical presentation. Serious manifestations include extensive morphea that may involve the entire skin or linear forms, especially in children, where they may be severe, especially on the face. There are no immunological markers clearly associated with morphea and no causative agents have been implicated in its pathogenesis, although sclerodermiform dermatitis is reported to be associated with some drugs and toxic agents.

TREATMENT

There is no consensual treatment for morphea. Treatment should be decided according to severity and extent of lesions. Limited lesions may be treated with local steroids such as class IV corticosteroids. Systemic treatment (methotrexate) should be discussed in extensive and linear forms when there is a risk of functional or esthetic complications.

Critères de classification des sclérodermies

Classification criteria of scleroderma aim to delineate the different clinical forms of the disease, which are associated with different prognoses. The basic classification between localized and systemic scleroderma remains pertinent. Among the former, the problems are essentially esthetic or sometimes functional; but the second may yield many other problems which are pertinent to function but also to life, owing to the involvement of body organs, including lungs, heart, digestive tract, kidneys and locomotor system. Overall, the quality of life of scleroderma patients is often poor. The patients are subclassified according to the skin involvement. Those patients with systemic scleroderma involving the trunk are classified as "Cutaneous diffuse systemic scleroderma"; the association of Raynaud's phenomenon, capillaroscopic abnormalities and specific autoantibodies defines "limited systemic scleroderma"; among the latter patients, those with distal skin involvement are classified "Cutaneous limited systemic sclerosis". The old term "CREST" tends to be abandoned due to its lack of specificity.

Systemic and localized scleroderma in children: current and future treatment options

Scleroderma is a group of rare and complex diseases with varied clinical manifestations. The most obvious manifestation of the diseases is skin hardening and sclerosis. Scleroderma can be divided into two main subgroups: systemic and localized. The systemic form, also known as systemic sclerosis, involves diffuse skin involvement and potentially severe visceral involvement. Localized scleroderma on the other hand is more common in children and usually confined to a specific region of the body with no internal organ involvement. The juvenile forms of systemic sclerosis and localized scleroderma are important conditions in children because of the clinical severity and substantial mortality of systemic scleroderma and the major growth defects associated with childhood-onset localized disease even if the active disease itself is self-limited. The pathogenic pathways of the various forms of scleroderma are only partially defined, but the main defect in scleroderma is abnormal collagen deposition leading to eventual fibrosis in the skin as well as multiple organ systems such as the heart and lungs in juvenile systemic sclerosis. Therapeutics are divided into three main subgroups for systemic sclerosis: antifibrotics, anti-inflammatories, and vasodilators. For localized disease, anti-inflammatories, vitamin D analogs, and UV irradiation have been investigated. However, the infrequency of scleroderma in the pediatric population plus the fact that this disease is very often self-limiting makes randomized controlled trials very difficult. It is for this reason that most data on treatment modalities for this disease have been extrapolated from studies in adult patients. There is no one therapy for systemic sclerosis or localized scleroderma that has proven to be very effective or significantly disease modifying. However, current therapeutic strategies must be initiated early in the disease course for maximum beneficial clinical effects. New interventions such as autologous stem cell transplant and cytokine-directed therapies are under investigation as potential treatments for this complex disease.

Low-dose UVA1 phototherapy in systemic sclerosis: effects on acrosclerosis

BACKGROUND

Increased collagen synthesis, vascular damage, and T-lymphocytic infiltration contribute to the development of systemic sclerosis. Preliminary studies revealed the effectiveness of low-dose UVA1 phototherapy in acrosclerosis.

OBJECTIVE

We sought to confirm data of a pilot study revealing the efficacy of low-dose UVA1 irradiation in acrosclerosis in a larger number of patients.

METHODS

Symptoms of 18 patients receiving low-dose UVA1 phototherapy were evaluated clinically and biometrically in an open, nonrandomized study. A number of pretherapeutic and posttherapeutic biopsy specimens were tested immunohistochemically for matrix-metalloproteinase-1.

RESULTS

UVA1 irradiation led to softening of former stiffness reflected by a significant decrease of the hand score, increase of total skin distension, and reduction of skin thickness. Posttherapeutically, matrix-metalloproteinase-1 immunolabeling revealed a significant dermal elevation of collagenase.

CONCLUSION

Low-dose UVA1 phototherapy is a capable treatment option for acrosclerosis. Its beneficial effect may be mediated by the induction of collagenases and a reduction of collagen deposition and cellular infiltration.

Histometric data obtained by in vivo confocal laser scanning microscopy in patients with systemic sclerosis

BACKGROUND

It would be a benefit if time-saving, non-invasive methods could give hints for diagnosing systemic sclerosis. To investigate the skin of patients with systemic sclerosis using confocal laser scanning microscopy in vivo and to develop histometric parameters to describe characteristic cutaneous changes of systemic sclerosis observed by this new technique, we conducted an exploratory study.

MATERIALS AND METHODS

Fifteen patients with systemic sclerosis treated with extracorporal photopheresis were compared with 15 healthy volunteers and 10 patients with other disorders also treated with extracorporal photopheresis. All subjects were investigated using confocal laser scanning microscopy in vivo.

RESULTS

Micromorphologic characteristics of skin of patients with systemic sclerosis and measuring parameters for melanisation, epidermal hypotrophy, and fibrosis for dislocation of capillaries by collagen deposits in the papillary dermis were evaluated. An interesting finding was an increased thickness of the tissue in the dermal papillae superior to the first dermal papilla vessel. It was also possible to reproduce characteristic histologic features by confocal laser scanning microscopy in vivo. Histometric parameters for fibrosis and vascular features developed in this study showed significant differences in patients with systemic sclerosis compared to controls.

CONCLUSIONS

Although the predominant histopathological features in systemic sclerosis are findings of the reticular dermis and the subcutis, and in histopathological investigation the epidermis seems to remain unaffected by the disease, we have demonstrate some characteristic differences in the epidermis and papillary dermis by confocal laser scanning microscopy in vivo. Some of them have not been described so far. However, to use this technique as a tool for diagnosis and/or staging of systemic sclerosis, further studies are needed investigating the sensitivity and specificity of the histometric parameters developed in this study.

Scleroderma in children and adolescents

The scleroderma disorders remain challenging conditions in pediatric rheumatology to understand pathologically and indeed for which to provide care. It is clear that much progress is being made in the clinical approach to understanding this group of group of disorders. It seems likely that the different lesions of LS may represent unique immunopathogenic mechanisms or perhaps reflect unique genetic or other characteristics of the patients themselves. To take advantage of the revolution in therapies now occurring in rheumatology it is critical that controlled clinical trials are developed with appropriate agreed upon outcome measures for both localized and systemic disease.

Scleroderma-like cutaneous syndromes

Several distinct entities associated with dermal fibrosis can mimic scleroderma/systemic sclerosis. The list of scleroderma-like conditions or scleroderma variants includes eosinophilic fasciitis, localized forms of scleroderma, scleredema and scleromyxedema, keloids, and environmental exposure-associated conditions including eosinophilia-myalgia syndrome and pseudosclerodermas induced by various drugs. Although these conditions are relatively uncommon, their accurate recognition is essential to avoid misdiagnosis and inappropriate therapy. The pathogenesis of these scleroderma variants appears to share similarities with each other and with that of scleroderma. Better understanding of scleroderma-like disorders is emerging through epidemiologic investigations, and in vivo and in vitro experimental research. Activation of eosinophils and disordered regulation of fibroblast collagen synthesis, apoptosis, and proliferation are recurrent findings in these disorders. The etiologic role of infection with Borrelia species or other microorganisms remains controversial. Cytokines such as transforming growth factor-beta, interleukin-4, interleukin-13, and connective tissue growth factor contribute to fibrosis in these disorders by inducing an accentuated and persistent fibrogenic response to tissue injury. The role of genetic factors in susceptibility and clinical expression of scleroderma-like conditions remains to be systematically addressed. Because of the relative rarity of these conditions, few well-controlled clinical treatment trials have been performed. In addition, there is no consensus on optimal management. Much anecdotal information and small clinical series indicate that phototherapy may have a role in the treatment of scleroderma-like conditions.

Recognition and management of scleroderma in children

Juvenile scleroderma is a rare disease of childhood. The 2 main forms are localised and systemic scleroderma, although the pathogenesis of both forms is still unclear. The main clinical characteristic is the presence of skin sclerosis. Localised scleroderma can be divided into 3 different subtypes: morphoea, linear scleroderma and 'coup de sabre' lesions. The incidence is 0.2 to 0.4 per 100,000. 25 to 40% of patients are rheumatoid factor positive and 23 to 67% antinuclear antibody positive. An increased number of eosinophils occur in 31% of patients. Systemic sclerosis is an even rarer disease; approximately 10% of patients evolve the disease before the age of 18 years. The clinical presentation and disease course differ from the adult disease. This is reflected in the much better outcome. With regard to therapeutic options, there is still no gold standard for either form of the disease.

Nephrogenic Fibrosing Dermopathy

This report details the histopathologic findings in a unique fibrosing disorder that recently emerged among patients with renal disease. The affected patients were initially identified among recipients of renal transplants at a single institution, but later cases at other centers were identified, and included patients receiving renal dialysis for a variety of different kidney diseases. The cutaneous changes consisted largely of indurated plaques and papules on the extremities and trunk. Systemic findings seen in scleromyxedema, which the condition resembles in some respects, were absent. By routine microscopy, the findings range from a very subtle proliferation of dermal fibroblasts in early lesions, to a florid proliferation of fibroblasts and dendritic cells in fully developed cases. Thick collagen bundles with surrounding clefts are a prominent finding, and a variable increase in dermal mucin and elastic fibers was usually evident with special stains. CD-34 positive dermal dendrocytes were floridly abundant, with dendritic processes aligned with elastic fibers and around collagen bundles in a dense network. Factor XIIIa and CD-68 positive mono-and multinucleated cells are also present in increased numbers. Electron microscopy highlighted increased elastic fibers closely apposed to dendritic cell processes. The entire dermis was commonly involved, with increased spindle cells, collagen, mucin, and elastic fibers extending through the subcutis along the septa of fatty lobules. In some instances, the process resembled a sarcoma on histopathologic examination. The recent emergence of this condition and the apparent clustering of cases in specific dialysis centers initially suggested a possible infectious and/or toxic agent. To date, however, no such agent has been identified. We propose the term "nephrogenic fibrosing dermopathy (NFD)" until a specific cause can be identified.

The Th1/Th2 paradigm in the pathogenesis of scleroderma, and its modulation by thalidomide

The immunity generated in response to an antigenic stimulus can result in at least two distinct subclasses of immune responses, commonly referred to as Th1 and Th2. This review describes Th1- and Th2-type immune responses in animal models and in human mediated disease. Evidence obtained from working within these models suggests that manipulating the Th1/Th2 balance in the immune response can alter disease processes. The possible application of this strategy in scleroderma is presented. The immune modulating effects of the drug thalidomide on Th1 and Th2 immunity are also described, along with the drug's potential application to disease processes like scleroderma.

Morphea limited to the superficial reticular dermis: an underrecognized histologic phenomenon

Morphea (localized scleroderma) is a disease of unknown etiology, presenting as circumscribed areas of indurated skin. Histologically, most cases of morphea feature thickened collagen bundles in the deep reticular dermis, sometimes also extending into the superficial dermis or into the subcutis. We present six cases of morphea in which typical histologic features were restricted to the superficial dermis and contrast these with 27 additional biopsies of conventional morphea seen during the same time period. Sections were stained for elastic fibers, and dermal dendritic cells were labeled with antibodies to CD34 and Factor XIIIa. All six cases showed thickened collagen bundles restricted to the superficial dermis, sparing the deep dermis and without associated evidence of lichen sclerosus et atrophicus (LSA). Dermal elastic fibers were not appreciably decreased in number. There was loss of CD34-positive dermal spindle cells in each of our six superficial examples of morphea, which was restricted to the area of altered collagen in four of the six cases. This report highlights the distinctly uncommon phenomenon of morphea presenting solely as alteration of the superficial reticular dermis, without features of LSA. The selective loss of CD34-labeled spindle cells may provide information regarding the role of these putative immune accessory cells in morphea. Recognition of this manifestation of morphea may be helpful diagnostically.