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C M Black

Publications and source records attributed to C M Black.

At least 37 records · Page 2Linked to original sources

A cross-sectional comparison of three self-reported functional indices in scleroderma.

OBJECTIVES: In scleroderma, outcome measures such as skin score provide only limited information about the functional impact of the disease. The requirement for validated and convenient instruments that reliably reflect disease morbidity is now recognized. This study compares the Disability Index of the Health Assessment Questionnaire (HAQ-DI) with two more recently developed scleroderma-specific tools: scleroderma-visual analogue scales (scleroderma-VAS) and the UK scleroderma Functional Score (UKFS). In addition, the use of clinical and laboratory measures as predictors of disease severity have been examined. METHODS: One hundred and fifteen consecutive patients were studied. Subjects completed the 20-item HAQ-DI, the scleroderma-VAS and a questionnaire related to hand and muscle function (UKFS). Clinical details, measurement of maximal hand-spread, fist-closure and investigations for internal organ involvement were recorded. RESULTS: Over 68% of patients with diffuse disease had moderate to severe disease on the UKFS, compared with 44% with limited disease. The mean UKFS in diffuse disease was 14.7 (s.d. 9.1) and 10.6 (s.d. 8.5) in the limited subset (P=0.02). The mean HAQ-DI in diffuse disease was 1.23 (s.d. 0.77) and 0.79 (s.d. 0.75) in the limited subset (P=0.005). The HAQ-DI showed significant correlation with UKFS (r=0.9; P < 0.001). Several clinical and laboratory measures were associated with higher HAQ-DI and UKFS. CONCLUSIONS: This is the first comparative study of the UKFS and the HAQ-DI. These data show a strong correlation between assessment methods. Higher scores correlated with clinical and laboratory indicators of severe disease. Used together, these inexpensive tools assess general and organ-specific symptoms, as well as functional limitation.

Adult↗

Significance of plasma N-terminal pro-brain natriuretic peptide in patients with systemic sclerosis-related pulmonary arterial hypertension.

OBJECTIVES: A single centre pilot study to investigate the role of the plasma N-terminal pro-brain natriuretic peptide (N-T proBNP) assay to risk stratify patients with suspected pulmonary arterial hypertension (PAH) from a background SSc population. METHODS: Out of 49 SSc patients, 23 had and 26 did not have PAH. Right ventricular haemodynamic variables, six-minute walk test and plasma N-T proBNP levels were recorded from patients catheterised for suspected PAH (23 with PAH and 11/26 without PAH). RESULTS: Mean value of N-T proBNP for SSc patients with PAH was 3365 (standard error 1095) pg/ml compared to 347 (174) pg/ml for patients without PAH. There was a statistically significant correlation (P < 0.05) between N-T proBNP values and (i) mean pulmonary artery pressure (r = 0.53), (ii) right ventricular end diastolic pressure (r = 0.59) and (iii) pulmonary vascular resistance (r = 0.49). Receiver operator characteristic curve analysis showed that a cut-off value of 395.34 pg/ml had a sensitivity of 0.69 and specificity of 1.0. CONCLUSIONS: N-T proBNP estimation in systemic sclerosis-related pulmonary hypertension is a potentially useful diagnostic tool with a high specificity and negative predictive value. This test has the potential to have an important role in risk stratification and monitoring of therapy in the future.

Adult↗

Etanercept-induced systemic lupus erythematosus.

Tumour necrosis factor (TNF) is a pro-inflammatory cytokine with a role in the pathogenesis of a number of conditions including rheumatoid arthritis, psoriasis, psoriatic arthritis, ankylosing spondylitis and Crohn's disease. Etanercept (Enbrel; Immunex Corp., Seattle, WA, USA) is a recombinant soluble fusion protein of TNF-alpha type II receptor and IgG which acts by blocking the action of TNF-alpha. It is licensed for use in rheumatoid arthritis and juvenile chronic arthritis. A number of studies report the development of antinuclear and anti-double-stranded DNA antibodies in patients treated with TNF antagonists for rheumatoid arthritis. There are few reports of the development of clinical features of discoid, subacute or systemic lupus erythematosus. We present one of the first reported cases of etenercept-induced systemic lupus erythematosus and review the literature of lupus and TNF antagonists.

Antirheumatic Agents↗

Differentiation of primary and secondary Raynaud's disease by carotid arterial stiffness.

INTRODUCTION: primary Raynaud's disease may be difficult to differentiate clinically from the secondary form with an underlying connective tissue, haematological, neurovascular or drug-induced disorder. We undertook a study to determine the elastic carotid and muscular femoral arterial biomechanical properties and intima-media thickness (IMT) in subjects with primary and secondary Raynaud's disease, to assess whether these parameters could differentiate the two conditions. METHODS: twenty patients with primary Raynaud's disease and 53 subjects with secondary Raynaud's associated with scleroderma (systemic sclerosis, SSc) had measurements of their carotid and femoral wall mechanics with a duplex scanner coupled to a Wall Track system. Their age, gender, body mass index, heart rate, systolic and diastolic blood pressures, presumed cardiovascular load, plasma creatinine, fasting cholesterol, triglyceride and glucose concentrations were also measured. RESULTS: the carotid elastic properties [mean (SD): elastic modulus: 560 (180) vs 1204 (558) mmHg,p <0.001 and stiffness index: 5.69 (1.35) vs 11.92 (6.4), p<0.001 for primary and secondary Raynaud's respectively] were significantly impaired in patients with secondary Raynaud's disease even after adjustment for potentially influencing physiological and biochemical variables. There were no statistical differences in the femoral elastic properties or the carotid and femoral IMTs between the two groups. CONCLUSION: Duplex determination of the carotid elasticity or stiffness is different in primary Raynaud's phenomenon compared with secondary Raynaud's associated with SSc. This may be a useful non-invasive tool, in addition to autoantibody markers and nail-fold capillaroscopy, to differentiate between the two forms of Raynaud's phenomenon.

Adult↗

Calculated glomerular filtration rate is a useful screening tool to identify scleroderma patients with renal impairment.

OBJECTIVES: Although it only occurs in a minority of patients, renal involvement is a life-threatening complication of scleroderma (SSc). We have investigated the utility of two formulae to calculate glomerular filtration rate (GFR) in a population of SSc patients. METHODS: Twenty-six patients (20 female, 6 male, median age 58 yr, age range 12-80 yr) satisfied our criteria for inclusion in a retrospective comparison of measured and calculated GFR. GFR was measured using (51)Cr-EDTA. The modified Cockcroft and Gault formula and equation 7 from the Modification of Diet in Renal Disease (MDRD) were used to calculate GFR. RESULTS: Eighteen out of 19 patients analysed with a serum creatinine concentration less than the upper limit of the normal range had a measured GFR outside the normal range. Three patients with a normal creatinine concentration had a measured GFR <60 ml/min and in each of these the calculated GFR was also abnormal. All patients with a measured GFR <60 ml/min were identified using both the MDRD and the modified Cockcroft and Gault formula to calculate GFR. The greatest correlation between measured and calculated GFR was seen when the MDRD formula, which employs demographic and serum variables, was used in patients with body surface area (BSA) >1.4 m(2) who were not taking Iloprost (r=0.91). Use of the Cockcroft and Gault formula to calculate creatinine clearance with a correction factor for GFR, the inclusion of patients taking Iloprost and the inclusion of patients with BSA <1.4 m(2) were all associated with a lower degree of correlation. CONCLUSION: Serum creatinine is a poor marker of renal function in SSc patients. Calculating GFR from demographic and serum variables is a simple technique to identify SSc patients who have abnormal renal function. The authors recommend the use of the MDRD formula.

Adolescent↗

Prevalence and outcome in systemic sclerosis associated pulmonary arterial hypertension: application of a registry approach.

OBJECTIVE: To determine the prevalence of systemic sclerosis associated pulmonary arterial hypertension (SScPAH), evaluate outcome, and identify predictors of mortality in a large patient cohort. METHODS: A prospective four year follow up study of 794 patients (722 from our own unit and 72 referrals). All patients screened for PAH using a combination of echocardiography, lung function testing, and clinical assessment. Patients with suspected raised pulmonary artery systolic pressures of >35 mm Hg, carbon monoxide transfer factor (TLCO) <50% predicted, or a precipitous fall in TLCO >20% over a one year period with no pulmonary fibrosis, and patients with SSc with breathlessness with no pulmonary fibrosis found were investigated with right heart catheterisation. All patients with SScPAH were treated in accordance with current best practice. RESULTS: The prevalence of PAH was 12% (89/722) by right heart catheter. The survival was 81%, 63%, and 56% at 1, 2, and 3 years from the diagnosis (in 89 patients from our own cohort and 59/72 referrals). Haemodynamic indices of right ventricular failure--raised mRAP (hazard ratio 21), raised mPAP (hazard ratio 20), and low CI (hazard ratio 11) predicted an adverse outcome There was no significant difference in survival between patients with SScPAH with (n=40) and without (n=108) pulmonary fibrosis (p=0.3). CONCLUSIONS: The prevalence of SScPAH in this cohort was similar to that of other catheter based studies and lower than that of previous echo based studies. The 148 patients with SScPAH actively treated had comparable outcomes to those of the cohorts with primary pulmonary hypertension. A high mRAP was the strongest haemodynamic predictor of mortality. To improve prognosis, future treatments need to be implemented at an earlier disease stage to prevent right ventricular decompensation.

Aged↗

Predictors of end stage lung disease in a cohort of patients with scleroderma.

OBJECTIVES: To estimate the incidence of severe lung disease in patients with scleroderma and identify the combination(s) of features present at first assessment which would be useful to predict future risk of severe lung disease. METHODS: Data were analysed on 561 patients with disease onset occurring on or after 1 January 1982 and disease duration of less than five years before the first assessment. Detailed clinical and laboratory assessments were undertaken at the initial visit. End stage lung disease was defined as pulmonary hypertension requiring continuous ambulatory iloprost, or pulmonary fibrosis requiring continuous oxygen, or death from a scleroderma related lung disease. Patient status was determined at 31 December 1997. The best subset of predictors was identified by Cox regression analysis. RESULTS: In all, 24 patients reached end stage lung disease. The cumulative incidences were 4%, 6%, and 12% at five, seven, and 14 years respectively. As expected, the lung function tests at baseline, including being in the lowest third of either diffusing lung capacity (hazard ratio (HR) = 18.2, 95% confidence interval (CI) 3.5 to 93.8) or of forced vital capacity (HR=4.1, 95% CI 1.1 to 15.2), were highly significant predictors of end stage lung disease. Interestingly, apart from the presence of proteinuria, none of the other baseline variables, including the extent of skin disease and serological markers, were predictive of severe lung disease. CONCLUSION: End stage lung disease was infrequent in this large cohort, but the cumulative incidence increased importantly with time. The risk can be predicted from baseline assessment of pulmonary function. In particular, those with normal pulmonary function at baseline are at very low risk.

Adolescent↗

European Scleroderma Study Group to define disease activity criteria for systemic sclerosis. III. Assessment of the construct validity of the preliminary activity criteria.

OBJECTIVE: To further assess the construct validity of the three European Scleroderma Study Group (EScSG) preliminary activity indices for systemic sclerosis (SSc): for SSc as a whole, for diffuse SSc (dcSSc), and for limited SSc (lcSSc). METHODS: 30/290 SSc clinical charts collected for the EScSG study used to develop activity criteria for SSc were selected and sent to four clinical experts in SSc. The experts ranked the charts from 1 to 30 (1=lowest activity, 30=highest activity). The relationships among the ranks given by each investigator and each of the three scores, and between any two of the ranks were investigated. RESULTS: A consistently significant correlation (r(s)=0.530-0.712) was found between the ranks given by each of the four investigators and the index for the entire patient group. A similar level of agreement was detected between each couple of the four experts (r(s)=0.428-0.720). Moreover, the ranks given in patients with an index >3 were significantly higher than those given for patients with an index < or =3. This cut off point had previously been shown to best discriminate patients with active disease. CONCLUSIONS: Of the originally developed activity indexes, the whole series index has been externally validated. The index comprises the first preliminary, but necessary, groundwork to improve the concept of disease activity in SSc, which is still ill defined. It can be used as a preliminary activity index in clinical investigational studies.

Humans↗

Raynaud's phenomenon after radical radiotherapy for tumours of the head and neck.

Endothelial cell injury is implicated in the development of radiation induced tissue damage and may also be involved in the pathophysiology of secondary Raynaud's phenomenon. Two patients are presented in whom the typical symptoms and signs of Raynaud's phenomenon developed as a late complication of radical radiotherapy. One had Raynaud's of the tongue and one of the lip. Both patients had a prior history of primary Raynaud's phenomenon and in each case the symptoms were repeatedly precipitated by sudden cold exposure. The possible pathogenesis of radiation induced Raynaud's phenomenon in the head and neck region is discussed.

Aged↗

Juvenile-onset localized scleroderma activity detection by infrared thermography.

OBJECTIVE: The aim of this study was to define the clinical utility of infrared thermography in disease activity detection in localized scleroderma (LS). METHODS: We retrospectively reviewed 130 thermal images of 40 children with LS and calculated the sensitivity and specificity of thermography, comparing clinical descriptions of the lesions and contemporary thermographs. The reproducibility of thermography was calculated by using the weighted kappa coefficient to determine the level of agreement between two clinicians who reviewed the thermographs independently. RESULTS: The sensitivity of thermography was 92% and specificity was 68%. Full concordance between the two clinicians was observed in 91% of lesions, with a kappa score of 0.82, implying very high reproducibility of this technique. CONCLUSION: Our results demonstrate that thermography is a promising diagnostic tool when associated with clinical examination in discriminating disease activity, as long as it is applied to lesions without severe atrophy of the skin and subcutaneous fat. Further evaluation is needed to determine whether thermography can predict the future progression of lesions.

Age of Onset↗

Non-invasive measurement of biomechanical skin properties in systemic sclerosis.

OBJECTIVE: To evaluate biomechanical properties of skin in patients with systemic sclerosis (SSc) using the BTC-2000 suction device. METHODS: Twenty five patients with limited cutaneous SSc (lcSSc), 20 patients with diffuse disease (dcSSc), and 25 age matched healthy controls were evaluated. Viscoelastic deformation (VED, mm), elastic deformation (ED, mm), ultimate deformation (UD, mm), and pressure-deformation ratio (PDR, mm Hg/mm) were measured on the dorsal surface of the forearm, shoulder, and above the trapezius muscle on the back. RESULTS: Indices of skin extensibility (VED, ED, UD) were reduced and resistance to stress (PDR) increased in patients with dcSSc compared with healthy controls, or patients with lcSSc, at all three sites (p<0.001). At all sites, and overall, UD, ED, and VED were lower and PDR was higher at skin score above grade 2, compared with clinically normal skin. For both lcSSc and dcSSc biomechanical differences from controls were found even at sites of clinically normal skin. CONCLUSION: BTC-2000 is a sensitive tool for clinical evaluation of skin involvement in SSc and may be a valuable adjunct to skin sclerosis score in disease monitoring.

Adult↗

Tumour necrosis factor-alpha production in fibrosing alveolitis is macrophage subset specific.

BACKGROUND: Previous studies have revealed that tumour necrosis factor (TNF)-alpha is upregulated in fibrosing alveolitis (FA) in humans. The aim of this study was to compare the TNF-alpha secretory profile of alveolar macrophages (AMs) and peripheral blood monocytes (Mos) of patients with cryptogenic FA and systemic sclerosis (SSc), a rheumatological disorder in which lung fibrosis can occur. In particular, we wished to assess whether TNF-alpha levels differ between SSc patients with FA (FASSc) and a nonfibrotic group. METHODS: The reverse haemolytic plaque assay was used to evaluate the secretion of cytokine at a single cell level while immunostaining allowed subtyping of AMs and Mos. RESULTS: This study demonstrated a difference in total TNF-alpha levels produced by AMs when the levels in subjects with FA (cryptogenic FA and FASSc) were compared to levels in either SSc patients without FA (P = 0.0002) or normal healthy controls (P < 0.001). In addition, AMs from patients with FASSc secreted more TNF-alpha than those of patients with no FA (P = 0.003). In contrast, there were no significant differences in Mo TNF-alpha secretion between the groups. A positive correlation was found between total TNF-alpha level and number of neutrophils obtained by bronchoalveolar lavage from patients with FA (r = 0.49, P < 0.04). Finally, it was demonstrated that there was significant heterogeneity of TNF-alpha secretion and that a numerically significant subset of mononuclear phagocytes, RFD7, was responsible for more than 80% of TNF-alpha production. CONCLUSION: By demonstrating the primary cell source of TNF-alpha in FASSc, more accurately targeted, possibly localized, anti-TNF strategies might be employed with success in the future.

Animals↗

CTGF and SMADs, maintenance of scleroderma phenotype is independent of SMAD signaling.

In normal adult fibroblasts, transforming growth factor-beta (TGFbeta) induces the expression of connective tissue growth factor (CTGF). CTGF independently promotes fibroblast proliferation and matrix deposition, and in acute models of fibrosis promotes cell proliferation and collagen deposition acting synergistically with TGFbeta. In contrast to normal fibroblasts, fibroblasts cultured from fibrotic tissues express high basal levels of CTGF, even in the absence of added TGFbeta. Induction of transcription by TGFbeta requires the action of SMAD proteins. In this report we have investigated the role of SMADs in the TGFbeta-induction of CTGF in normal fibroblasts and in the elevated levels of CTGF expression found in dermal fibroblasts cultured from lesional areas of patients with scleroderma, a progressive fibrotic disorder that can affect all organs of the body. We have identified a functional SMAD binding site in the CTGF promoter. TGFbeta-induction of CTGF is dependent on SMAD3 and SMAD4 but not SMAD2 and is p300-independent. However, mutation of the SMAD binding site does not reduce the high level of CTGF promoter activity observed in dermal fibroblasts cultured from lesional areas of scleroderma patients. Conversely, the previously termed TGFbetaRE in the CTGF promoter is required for basal CTGF promoter activity in normal fibroblasts and for the elevated level of CTGF promoter activity in scleroderma fibroblasts. Thus, the maintenance of the fibrotic phenotype in scleroderma fibroblasts, as visualized by excess CTGF expression, appears to be independent of SMAD-dependent TGFbeta signaling. Furthermore, given CTGF's activities, the high level of CTGF expression observed in scleroderma lesions may contribute to the excessive scarring observed in this disorder.

3T3 Cells↗

Cytochrome P2 polymorphisms and susceptibility to scleroderma following exposure to organic solvents.

OBJECTIVE: To determine whether there are specific cytochrome P450 (CYP2) alleles that increase susceptibility to scleroderma in individuals who have been exposed to organic solvents. METHODS: CYP alleles at 2 loci, 2E1 and 2C19, were compared in 7 patients who had developed scleroderma after exposure to solvents versus 71 patients with scleroderma without solvent exposure ("sporadic" disease) and 106 population controls. RESULTS: The 2E1*3 allele was found in 2 of the 7 patients who had been exposed to organic solvents, with a greater frequency than occurred in either the disease controls or the population controls (odds ratio [95% confidence interval] 9.1 [1.5-59.1] and 10.2 [1.8-62.2], respectively). All 7 patients with solvent exposure carried the 2C19EM genotype, compared with 89% of patients with sporadic scleroderma. CONCLUSION: Our results suggest that alleles at CYP loci may be involved in increasing susceptibility to scleroderma among subjects who have been exposed to organic solvents.

Case-Control Studies↗

Activation of a fibroblast-specific enhancer of the proalpha2(I) collagen gene in tight-skin mice.

OBJECTIVE: Reporter transgenes were introduced into the type 1 tight-skin (Tsk1/+) mouse model of scleroderma to test the hypothesis that fibroblast-specific genetic programs are activated in fibrosis. METHODS: Transgenes harboring upstream fragments of the 5' flanking region of the mouse proalpha2(I) collagen gene (Col1a2), linked to a 400-bp minimal Col1a2 promoter driving an Escherichia coli beta-galactosidase (LacZ) reporter gene, were introduced into Tsk1/+ mice by breeding. Expression of these transgenes, which function as lineage-specific markers of fibroblast differentiation, was compared between the Tsk-LacZ mice and non-Tsk littermates. Responsiveness of these constructs to the profibrotic cytokine, transforming growth factor beta1 (TGFbeta1), was investigated by transient transfection of reporter constructs in tissue-culture cells. RESULTS: There was significant activation of reporter genes harboring the upstream enhancer in Tsk1/+ mice starting from 1 week of age. This was maximal at 6 weeks old (mean +/- SD 237 +/- 24% of non-Tsk controls; P= 0.001). Recombinant TGFbeta1 significantly activated reporter genes regulated by the upstream enhancer in transient transfection, and Tsk-LacZ fibroblasts showed elevated LacZ expression in tissue culture. CONCLUSION: These data suggest that activating signals in Tsk1/+ mice may act via fibroblast-specific regulatory elements within the murine Col1a2 gene. Although TGFbeta has been implicated in the pathogenesis of fibrosis, and reporter genes regulated by the upstream enhancer appear to be TGFbeta responsive in vitro, our results suggest that fibroblast-specific pathways may also be involved.

Animals↗

A reference map of human lung MRC-5 fibroblast proteins using immobilized pH gradient-isoelectric focusing-based two-dimensional electrophoresis.

We report the first protein map of human adult lung MRC-5 fibroblasts using isoelectric focusing-immobilized pH gradient-based two-dimensional polyacrylamide gel electrophoresis. MRC-5 is an immortalised cell line used in a wide range of investigations. The two-dimensional gel pattern of proteins generated from any given cell system provides a fingerprint that is unique to those cells. Therefore, the establishment of a protein map for a particular cell system provides a useful reference tool as a "master map" for subsequent studies using those cells. In this map a total of 98 protein spots were identified by comparative searches of the nucleotide and protein database using peptide masses obtained by matrix-assisted laser desorption/ionization time of flight following trypsin digestion. To increase the utility of the reference map, cells were cultured in both Dulbecco's modified Eagle medium (DMEM), the standard medium, and Roswell Park Memorial Institute (RPMI)-1640. Two-dimensional gel protein patterns of MRC-5 cultures were shown to be largely unaffected by the use of RPMI compared to DMEM, respectively. In combination with the reference map, the standardised protocol described provides a tool for comparative studies involving MRC-5 cells in which nonspecific variation is minimized.

Adult↗

Class II HLA associations with autoantibodies in scleroderma: a highly significant role for HLA-DP.

Scleroderma is a condition of variable phenotype characterised by fibrosis of the skin and internal organs. There is a range of disease-specific autoantibodies found in the sera of patients. The aims of this study were to: (1) investigate the role of the MHC and particularly HLA-DP in the production of autoantibodies; (2) investigate clinical associations with autoantibodies. We have performed HLA class II typing using PCR with sequence-specific primers on DNA samples from 202 scleroderma patients and 307 UK control subjects. All patients had well defined clinical phenotypes. Sera from patients were examined for the presence of disease specific autoantibodies in particular the anti-topoisomerase autoantibody (ATA), the anti-centromere autoantibody (ACA) and the anti-RNA polymerase autoantibody (ARA). There was a striking association between HLA-DPB1*1301 and ATA (Pcorr = 0.0001). In addition, ATA was associated with HLA-DRB1*11 and the anticentromere autoantibody (ACA) with HLA-DRB1*04, HLA-DRB1*08 (P = 0.001) and HLA-DQB1 alleles with a glycine residue at position 26. Very strong associations were detected between clinical phenotypes and autoantibodies. ATA was associated with pulmonary fibrosis (P = 0.00002), anti-RNA polymerase autoantibody (ARA) with renal involvement (P = 0.0000006) and diffuse skin disease (P = 0.00001), and ACA with limited skin involvement (P = 0.00002) and protection against pulmonary fibrosis (P = 0.0000003). We have identified a significant association between the ATA and HLA-DPB1*1301 which may provide an insight into how this autoantibody is formed. Patient clinical characteristics depend on the autoantibodies they carry.

Autoantibodies↗