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Biomedical subjects

John Varga

Publications and source records attributed to John Varga.

At least 37 records · Page 2Linked to original sources

Disruption of transforming growth factor beta signaling and profibrotic responses in normal skin fibroblasts by peroxisome proliferator-activated receptor gamma.

OBJECTIVE: In fibroblasts, transforming growth factor beta (TGF beta) stimulates collagen synthesis and myofibroblast transdifferentiation through the Smad intracellular signal transduction pathway. TGF beta-mediated fibroblast activation is the hallmark of scleroderma and related fibrotic conditions, and disrupting the intracellular TGF beta/Smad signaling may provide a novel approach to controlling fibrosis. Because of its potential role in modulating inflammatory and fibrotic responses, we examined the expression of the nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPAR gamma) in normal skin fibroblasts and its effect on TGF beta-induced cellular responses. METHODS: The expression and activity of PPAR gamma in normal dermal fibroblasts were examined by Northern and Western blot analyses, immunocytochemistry, flow cytometry, and transient transfections with reporter constructs. The same approaches were used to evaluate the effects of PPAR gamma activation by naturally occurring and synthetic ligands on collagen synthesis and alpha-smooth muscle actin (alpha-SMA) expression. Modulation of Smad-mediated transcriptional responses was examined by transient transfection assays using wild-type and dominant-negative PPAR gamma expression constructs. RESULTS: The PPAR gamma receptor was expressed and fully functional in quiescent normal skin fibroblasts. Whereas ligand activation of cellular PPAR gamma resulted in modest suppression of basal collagen gene expression, it abrogated TGF beta-induced stimulation in a concentration-dependent manner. This response was mimicked by overexpressing PPAR gamma in fibroblasts, and was blocked by a selective antagonist of PPAR gamma signaling or by transfection of fibroblasts with dominant-negative PPAR gamma constructs. Furthermore, PPAR gamma ligands abrogated TGF beta-induced expression of alpha-SMA, a marker of myofibroblasts. Stimulation of Smad-dependent transcriptional responses by TGF beta was suppressed by PPAR gamma despite the absence of a consensus PPAR gamma-response element in the targeted promoters. Ligand-induced activation of fibroblast PPAR gamma had no effect on protein expression of cellular Smad3 or Smad7. CONCLUSION: By abrogating of TGF beta-induced stimulation of collagen gene expression, myofibroblast transdifferentiation, and Smad-dependent promoter activity in normal fibroblasts, PPAR gamma may play a physiologic role in the regulation of the profibrotic response. Furthermore, our results suggest that PPAR gamma activation by pharmacologic agonists may represent a novel approach to the control of fibrosis in scleroderma.

Actins↗

Selective inhibition of activin receptor-like kinase 5 signaling blocks profibrotic transforming growth factor beta responses in skin fibroblasts.

OBJECTIVE: Members of the transforming growth factor beta (TGFbeta) cytokine superfamily play critical roles in both homeostasis and disease. In light of their profibrotic effects, these molecules are implicated in the pathogenesis of fibrosis. In fibroblasts, TGFbeta signals through the activin receptor-like kinase 5 (ALK-5) type I TGFbeta and triggers Smad and MAP kinase signaling pathways. Because targeting of TGFbeta signaling represents a potential approach to the treatment of systemic sclerosis (SSc) and other fibrotic disorders, we investigated the modulation of intracellular TGFbeta signal transduction by SB431542, the first small-molecule inhibitor of ALK-5 to be described. METHODS: Ligand-induced activation of the Smad signaling pathway in human dermal fibroblasts was examined by Western blot analysis and confocal immunocytochemistry. Modulation of profibrotic gene expression was investigated using Northern blot analysis, transient transfection assays, and confocal microscopy. Induction of TGFbeta production was evaluated by enzyme-linked immunosorbent assay. RESULTS: SB431542 abrogated TGFbeta-induced phosphorylation and nuclear importation of endogenous Smad2/3 and Smad4, and inhibited Smad3- and Smad2-dependent gene transcription. Treatment with SB431542 prevented TGFbeta-induced stimulation of collagen, fibronectin, plasminogen activator inhibitor 1, and connective tissue growth factor gene expression, TGFbeta autoinduction, and myofibroblast transdifferentiation, and it could reverse stimulation even when added to the cultures after TGFbeta. In contrast, STAT-6-mediated stimulation of collagen gene expression induced by interleukin-13 was not prevented by SB431542, indicating the specificity of blockade for ALK-5-dependent signaling. Furthermore, in contrast to its effects on receptor-activated Smad activation, SB431542 failed to prevent TGFbeta-induced activation of MAP kinases. CONCLUSION: The results indicate that SB431542 is a potent inhibitor of intracellular TGFbeta signaling in normal fibroblasts through selective interference with ALK-5-mediated Smad activation and Smad-dependent transcriptional responses. Therefore, SB431542 is useful as a novel experimental tool for gaining a detailed understanding of normal and aberrant TGFbeta signaling in SSc. Furthermore, as an anti-TGFbeta agent, SB431542 may represent a potential new approach to the treatment of fibrosis.

Activin Receptors, Type I↗

Antifibrotic therapy in scleroderma: extracellular or intracellular targeting of activated fibroblasts?

Therapeutic anticytokine approaches have revolutionized the treatment of chronic inflammatory diseases, and targeting of transforming growth factor-beta (TGF-beta), a key factor in the pathogenesis of fibrosis, is undergoing evaluation for scleroderma. Several considerations dictate a cautious approach to anti-TGF-beta interventions. These include the possibility of multiple cytokines having overlapping roles in the pathogenesis of fibrosis and concerns that, in light of its numerous homeostatic functions, blocking TGF-beta may have serious adverse consequences. Furthermore, as autonomously activated cells, scleroderma fibroblasts may be unresponsive to blockade of TGF-beta signaling. This article reviews the experimental evidence underlying these concerns, and indicates rational approaches to addressing and overcoming them.

Fibroblasts↗

Targeted disruption of TGF-beta/Smad3 signaling modulates skin fibrosis in a mouse model of scleroderma.

Transforming growth factor-beta (TGF-beta) is a potent stimulus of connective tissue accumulation, and is implicated in the pathogenesis of scleroderma and other fibrotic disorders. Smad3 functions as a key intracellular signal transducer for profibrotic TGF-beta responses in normal skin fibroblasts. The potential role of Smad3 in the pathogenesis of scleroderma was investigated in Smad3-null (Smad3(-/-)) mice using a model of skin fibrosis induced by subcutaneous injections of bleomycin. At early time points, bleomycin-induced macrophage infiltration in the dermis and local TGF-beta production were similar in Smad3(-/-) and wild-type mice. In contrast, at day 28, lesional skin from Smad3(-/-) mice showed attenuated fibrosis, lower synthesis and accumulation of collagen, and reduced collagen gene transcription in situ, compared to wild-type mice. Connective tissue growth factor and alpha-smooth muscle actin expression in lesional skin were also significantly attenuated. Electron microscopy revealed an absence of small diameter collagen fibrils in the dermis from bleomycin-treated Smad3(-/-) mice. Compared to fibroblasts derived from wild-type mice, Smad3(-/-) fibroblasts showed reduced in vitro proliferative and profibrotic responses elicited by TGF-beta. Together, these results indicate that ablation of Smad3 is associated with markedly altered fibroblast regulation in vivo and in vitro, and confers partial protection from bleomycin-induced scleroderma in mice. Reduced fibrosis is due to deregulated fibroblast function, as the inflammatory response induced by bleomycin was similar in wild-type and Smad3(-/-) mice.

Actins↗

Smad3 deficiency ameliorates experimental obliterative bronchiolitis in a heterotopic tracheal transplantation model.

Chronic allograft rejection manifested as obliterative bronchiolitis (OB) remains the single greatest impediment to long-term survival after lung transplantation. Transforming growth factor-beta1 (TGF-beta1) has been implicated in the tissue remodeling response associated with OB. Therefore, its intracellular signal transducer, Smad3, is a prime target of investigation. Herein, we examine the role of TGF-beta1, through Smad3, in the development of OB using heterotopic tracheal transplantation in wild-type and Smad3-null mice. TGF-beta1 was detectable within infiltrating mononuclear cells early after transplantation. Later it was detected in fibroblasts and in the connective tissue accumulating within the lumen and the airway wall of the transplanted allografts. Connective tissue growth factor had a similar time and tissue distribution. Nuclear detection of Smad3 and phosphorylated Smads within intraluminal fibroblasts coincided with increased intraluminal deposition of fibronectin and collagen. When transplanted into Smad3-null mice, allografts failed to organize the intraluminal exudates despite fibroblast accumulation and showed reduced fibronectin and collagen deposition. In culture, Smad3-deficient fibroblasts expressed reduced fibronectin in response to TGF-beta1 compared to wild-type cells. Together, these studies suggest that the TGF-beta signal transducer, Smad3, is required for the development of experimental OB in transplanted tracheas.

Animals↗

High-dose versus low-dose D-penicillamine in early diffuse systemic sclerosis trial: lessons learned.

OBJECTIVES: To review important findings, or lessons, that were learned about measures of response, design, conduct, and analysis of a randomized, controlled trial (RCT), even though the trial failed to demonstrate efficacy of d-penicillamine. METHODS: One hundred thirty-four patients with early (< or =18 months), diffuse systemic sclerosis (SSc) were entered into an RCT (high-dose [822 mg daily] vs low-dose [120 mg every other day] D-penicillamine) and were followed up regularly for up to 4 years. Because analysis failed to show efficacy for D-penicillamine in early diffuse SSc, all data were pooled for additional secondary analyses. RESULTS: This RCT showed that trials of potential disease-modifying interventions can be completed in SSc using the American College of Rheumatology guidelines. This RCT used an active control. After analysis, we were not able to tell whether either dose was effective or ineffective. That experience argues in favor of using placebo controls until such time as an active control can be found that truly modifies the disease. Skin score and the disability index of the Health Assessment Questionnaire (HAQ-DI) were valid predictors of outcome. Along with the physician global assessment, they also were valid measures of response. CONCLUSIONS: Even in studies that are therapeutically "negative," careful evaluation of the data can examine other hypotheses and thereby provide important insights into other aspects of trial design, outcome measures, patient function, and trial conduct.

Adult↗

The CcpA protein is necessary for efficient sporulation and enterotoxin gene (cpe) regulation in Clostridium perfringens.

Clostridium perfringens is the cause of several human diseases, including gas gangrene (clostridial myonecrosis), enteritis necroticans, antibiotic-associated diarrhea, and acute food poisoning. The symptoms of antibiotic-associated diarrhea and acute food poisoning are due to sporulation-dependent production of C. perfringens enterotoxin encoded by the cpe gene. Glucose is a catabolite repressor of sporulation by C. perfringens. In order to identify the mechanism of catabolite repression by glucose, a mutation was introduced into the ccpA gene of C. perfringens by conjugational transfer of a nonreplicating plasmid into C. perfringens, which led to inactivation of the ccpA gene by homologous recombination. CcpA is a transcriptional regulator known to mediate catabolite repression in a number of low-G+C-content gram-positive bacteria, of which C. perfringens is a member. The ccpA mutant strain sporulated at a 60-fold lower efficiency than the wild-type strain in the absence of glucose. In the presence of 5 mM glucose, sporulation was repressed about 2,000-fold in the wild-type strain and 800-fold in the ccpA mutant strain compared to sporulation levels for the same strains grown in the absence of glucose. Therefore, while CcpA is necessary for efficient sporulation in C. perfringens, glucose-mediated catabolite repression of sporulation is not due to the activity of CcpA. Transcription of the cpe gene was measured in the wild-type and ccpA mutant strains grown in sporulation medium by using a cpe-gusA fusion (gusA is an Escherichia coli gene encoding the enzyme beta-glucuronidase). In the exponential growth phase, cpe transcription was two times higher in the ccpA mutant strain than in the wild-type strain. Transcription of cpe was highly induced during the entry into stationary phase in wild-type cells but was not induced in the ccpA mutant strain. Glucose repressed cpe transcription in both the wild-type and ccpA mutant strain. Therefore, CcpA appears to act as a repressor of cpe transcription in exponential growth but is required for efficient sporulation and cpe transcription upon entry into stationary phase. CcpA was also required for maximum synthesis of collagenase (kappa toxin) and acted as a repressor of polysaccharide capsule synthesis in the presence of glucose, but it did not regulate synthesis of the phospholipase PLC (alpha toxin).

Adaptation, Physiological↗

Animal models of scleroderma.

Although no single animal model of systemic sclerosis (SSc) faithfully reproduces all features of the human disease, certain animal models that display some of the features of SSc are potentially useful as they may be helpful in gaining a better understanding of the pathogenesis of SSc as well as developing novel therapeutic interventions. This chapter gives the detailed description of the two most useful animal models of SSc: bleomycin-induced skin fibrosis and the sclerodermatous graft-vs-host disease in mice. It provides the methodology of the induction as well as the repertoire of the different approaches that can be used to investigate the skin fibrosis in these models, including histopathology, immunohistochemistry, dermal thickness, hydroxyproline content of the skin, and analysis of dermal cells by flow cytometry.

Animals↗

Pulmonary arterial hypertension in systemic sclerosis: clinical manifestations, pathophysiology, evaluation, and management.

It is increasingly recognized that significant pulmonary arterial hypertension (PAH) develops in more than 15% of patients with systemic sclerosis (SSc). As this complication of SSc may occur even in the absence of overt interstitial lung disease (isolated PAH), it has been likened to primary PAH and is attributable to intrinsic vascular pathology that is the hallmark of SSc. Deregulated activity of mediators controlling vasomotor tone has been implicated, and levels of endothelin-1 (ET-1) are elevated in the circulation and in the lungs. By causing enhanced vasoconstriction, vascular endothelial cell proliferation, smooth muscle hypertrophy, and irreversible vascular remodeling in the lungs, ET-1 appears to play a significant role in the pathogenesis of SSc-associated PAH. Although patients with the limited cutaneous form of SSc are more likely to develop PAH than those with the diffuse form, the true prevalence of PAH in SSc, and the risk factors for its development, are not yet known. Because the prognosis of patients with SSc-associated PAH is substantially worse than that of patients without this complication, intensive efforts are underway to develop sensitive screening strategies and effective treatments. Serial evaluation of SSc patients with Doppler echocardiography appears to be prudent. Antibodies against the centromere or fibrillarin proteins may be useful in identifying those patients with SSc at highest risk for developing PAH. The US FDA has approved a number of novel treatments, including long-acting oral ET-1 receptor antagonists such as bosentan and short-acting parenteral prostacyclin analogs, such as epoprostenol, for PAH. In particular, bosentan appear to be well tolerated, and short-term therapy results in improved exercise tolerance, improved hemodynamics, and possibly improved survival in patients with advanced PAH. These agents may be used alone, or possibly in combination with prostacyclin analogs. Therapeutic agents that modulate the synthesis of nitric oxide, and additional agents targeting the ET-1 signaling system are under preclinical development. Although the large-scale clinical trials that resulted in obtaining FDA approval for these agents were generally carried out in patients with primary PAH, it appears that patients with SSc-associated PAH respond similarly. Therefore, it is reasonable to conclude that ET-1 receptor antagonists and parenteral prostacyclin analogs should be used in SSc patients with moderate to severe PAH. The efficacy of these agents for treating patients with PAH who also experience significant interstitial lung disease, as occurs in many SSc patients, remains unknown. Additional important unresolved issues relate to the long-term efficacy of ET-1 receptor antagonists, and their effects on survival and progression of PAH. Additionally, it is not yet clear if early intervention for SSc patients with mild PAH is beneficial.

Humans↗

Expression and regulation of intracellular SMAD signaling in scleroderma skin fibroblasts.

OBJECTIVE: Scleroderma is characterized by excessive synthesis and accumulation of matrix proteins in lesional tissues. Transforming growth factor beta (TGFbeta) plays a central role in the pathogenesis of fibrosis by inducing and sustaining activation of fibroblasts; however, the underlying mechanisms are poorly understood. We undertook this study to examine the expression and function of SMADs, recently characterized intracellular effectors of TGFbeta signaling, in scleroderma fibroblasts. METHODS: Primary dermal fibroblasts obtained from 14 patients with scleroderma and from 4 healthy adult volunteers were studied. Northern analysis was used to determine the expression of endogenous SMAD messenger RNA (mRNA), and Western analysis was used to determine SMAD protein expression. Intracellular compartmentalization of cellular SMAD proteins in the presence and absence of TGFbeta was studied by antibody-mediated immunofluorescence confocal microscopy. The effect of TGFbeta blockade on SMAD subcellular distribution was determined using anti-TGFbeta antibodies as well as a dominant-negative TGFbeta receptor type II (TGFbetaRII) vector to disrupt TGFbeta responses. SMAD-regulated luciferase reporter expression was examined to investigate the potential functional significance of activation and nuclear accumulation of endogenous SMADs in scleroderma fibroblasts. RESULTS: Protein and mRNA levels of SMAD3, but not of SMAD4 or SMAD7, were variably elevated in scleroderma fibroblasts compared with those from healthy controls. In sharp contrast to control fibroblasts, which displayed predominantly cytoplasmic localization of SMAD3/4 in the absence of exogenous TGFbeta, in scleroderma fibroblasts SMAD3 and SMAD4 consistently showed elevated nuclear localization. Furthermore, phosphorylated SMAD2/3 levels were elevated and nuclear localization of phosphorylated SMAD2/3 was increased, suggesting activation of the SMAD pathway in scleroderma fibroblasts. Blockade of autocrine TGFbeta signaling with antibodies or by expression of dominant-negative TGFbetaRII failed to normalize SMAD subcellular distribution, suggesting that elevated nuclear SMAD import was due to alterations downstream of the TGFbeta receptors. The activity of a SMAD-responsive minimal promoter-reporter construct was enhanced in transiently transfected scleroderma fibroblasts. CONCLUSION: This study is the first to demonstrate apparently ligand-independent constitutive activation of the intracellular TGFbeta/SMAD signaling axis in scleroderma fibroblasts. SMAD signaling may be a mechanism contributing to the characteristic phenotype of scleroderma fibroblasts and playing a role in the pathogenesis of fibrosis.

Adult↗

Sustained activation of fibroblast transforming growth factor-beta/Smad signaling in a murine model of scleroderma.

Transforming growth factor-beta is responsible for triggering a cascade of events leading to fibrosis in scleroderma. The Smads are intracellular signal transducers recently shown to mediate fibroblast activation and other profibrotic responses elicited by transforming growth factor-betain vitro. To understand better the involvement of Smads in the pathogenesis of fibrosis, we examined Smad expression and activation in situ in a murine model of scleroderma. Bleomycin injections induced striking dermal infiltration with macrophages by 3 d, and progressive fibrosis by 2 wk. Infiltrating macrophages and resident fibroblasts expressed Smad3, the positive mediator for transforming growth factor-beta responses. Importantly, in bleomycin-injected skin, fibroblasts showed predominantly nuclear localization of Smad3 and intense staining for phospho-Smad2/3. Furthermore, phosphorylated Smad2/3 in fibroblasts was detected even after the resolution of inflammation. Expression of Smad7, the endogenous inhibitor of transforming growth factor-beta/Smad signaling, was strongly induced in dermal cells by transforming growth factor-beta, but not by bleomycin injections. Collectively, these results indicate that bleomycin-induced murine scleroderma is associated with rapid and sustained induction of transforming growth factor-beta/Smad signaling in resident dermal fibroblasts. Despite apparent activation of the intracellular transforming growth factor-beta signaling pathway in the lesional dermis, the expression of transforming growth factor-beta-inducible Smad7 was not upregulated. In light of the critical function of Smad7 as an endogenous inhibitor of Smad signaling that restricts the duration and magnitude of transforming growth factor-beta responses, and as a mediator of apoptosis, relative Smad7 deficiency observed in the present studies may account for sustained activation of transforming growth factor-beta/Smad signaling in lesional tissues. These findings raise the possibility that Smads plays an important part in the pathogenesis of fibrosis, and may therefore represent targets for selective anti-fibrotic interventions.

Animals↗

A descriptive analysis of hypertension and affiliated therapies in a military retiree population (ages 40-85 years) at Camp Lejeune, North Carolina.

Because current methods of tracking hypertension are time-consuming and expensive, the prevalence of hypertension in retired military populations is often unknown. Tracking military retiree hypertension is important because it can help to conserve scarce resources and save lives by preventing strokes and other diseases. Intended as a case study, an alternative method of tracking hypertension using pharmacy records and ambulatory data system records to confirm diagnosis of hypertension was used to determine the prevalence of hypertension in a retired military population (ages 40-85 years). The results indicated that matching pharmacy data with ICD9 401 diagnosis data and medical records is a more efficient method of tracking hypertension.

Aged↗

Information on diagnosis and management of systemic lupus erythematosus derived from the routine measurement of 8 nuclear autoantibodies.

OBJECTIVE: To determine the value of routine measurement of a panel of 8 nuclear autoantibodies (ANA/8) for the diagnosis and management of patients with systemic lupus erythematosus (SLE). METHODS: To estimate disease sensitivity of ANA/8, we studied 25 patients with new SLE and 114 with new and established SLE. To estimate disease specificity, 100 patients with other autoimmune rheumatic diseases were included. We used computerized statistical analysis of the level of 8 ANA in relation to clinical activity determined as Systemic Lupus Activity Measure disease activity scores (DAS). Data were collected retrospectively from the charts of 114 patients with 698 visits and evaluated by multiple and piece-wise linear regression analysis (PWLRA) and correlation and cluster analyses. RESULTS: The disease sensitivity of the 3 types of SLE profiles identified was 100% for new SLE patients (n = 25) and 87% for mixed SLE patients; the disease specificity was 98%. Autoantibody levels of anti-ssDNA, dsDNA, and Scl-70 were the best individual correlates of general and organ-specific DAS. Twenty-four percent (R2) of the variability in the general DAS was explained by the multiple regression (R = 0.49), with significant contribution made by anti-Scl-70 (beta = 0.39), dsDNA (beta = 0.17), Sm (beta = 0.10), and SSA (beta = 0.08). PWLRA indicated that for 68% of the 698 clinical presentations (average 6/patient), the observed DAS and the predicted DAS from autoantibody levels were both low and clustered; they were partially discrepant for the remaining 32%, which was explained by the relatively high correlation of DAS with prior changes in autoantibody levels (R = 0.6). The changes in DAS and in anti-dsDNA levels were significantly predicted by the multiple regression at one prior visit, with anti-ssDNA as the main contributor. CONCLUSION: The ANA/8 profile showed ~ 100% sensitivity and ~ 98% specificity for SLE and correlated with contemporary and subsequent changes in DAS and autoantibody levels. Among autoantibodies of this profile, anti-ssDNA (ssDNA) was the most sensitive indicator of SLE and the main contributor to prediction of subsequent changes in DAS.

Antibodies, Antinuclear↗

Predictors and outcomes of scleroderma renal crisis: the high-dose versus low-dose D-penicillamine in early diffuse systemic sclerosis trial.

OBJECTIVE: The reported frequency of scleroderma M01-R renal crisis (SRC) in diffuse systemic sclerosis (SSc; scleroderma) is 15-20%. Early use of angiotensin-converting enzyme (ACE) inhibitors has markedly improved outcome. The present analysis reexamines the prognostic factors for and outcome of SRC in a prospective cohort of patients with early diffuse SSc. METHODS: We retrospectively evaluated the cohort of SSc patients who participated in the High-Dose Versus Low-Dose D-Penicillamine in Early Diffuse SSc trial. Patients with diffuse cutaneous scleroderma were enrolled if their disease duration was <18 months. Because the trial failed to show a difference between treatment groups, the data were pooled. RESULTS: One hundred thirty-four SSc patients entered the observation period a mean +/- SD of 0.8 +/- 0.3 years after onset of SSc. SRC occurred in 18 patients a mean +/- SD of 0.9 +/- 1.1 years after entry. During a mean +/- SD 4.0 +/- 1.1 years of followup after entry, 9 of the 18 patients died (mean +/- SD 0.6 +/- 0.9 years after SRC onset). Baseline characteristics that predicted SRC included a modified Rodnan skin thickness score of >or=20 (P < 0.01), enlarged cardiac silhouette on radiograph (P = 0.04), large joint contractures (wrist, elbow, knee) (P = 0.008), and prednisone use at entry (P = 0.01). Baseline characteristics that did not predict SRC included age, sex, race, Health Assessment Questionnaire score, fist closure, handspread, lung involvement, muscle weakness, erythrocyte sedimentation rate, and platelet count. In 5 of 10 subjects for whom at least 2 sequential skin scores were available, skin scores increased significantly (P = 0.012) in the 6 months before onset of SRC. CONCLUSION: SRC occurred in 13% of patients soon (mean 11 months) after entry into the cohort. Predictors of SRC identified in this study included higher than average skin score, prednisone use at study entry, large joint contractures, and heart enlargement. Our data suggest, however, that low-dose prednisone alone was not associated with the onset of SRC, except in the appropriate clinical setting. Although ACE inhibitors and dialysis are now readily available, SRC continues to be associated with poor survival (in this study, 50% of patients with SRC died).

Adult↗