Classification Of Systemic Sclerosis Research Articles

Prevalence of systemic sclerosis in Split–Dalmatia county in Southern Croatia

This study aims to evaluate the prevalence of patients with systemic sclerosis (SSc) in Split-Dalmatia County in Southern Croatia. Patients were recruited from the medical records of University Hospital Split. Our Department of Rheumatology and Clinical Immunology is the only tertiary referral center for the Split-Dalmatia County, which has a population of 313,365 inhabitants aged over 18 years. Diagnoses were verified by medical record review. Cases of localized scleroderma (morphea and linear disease) were excluded. All patients were re-evaluated by the American College of Rheumatology (ACR) criteria for the classification of systemic sclerosis. Prevalence of SSc in Split-Dalmatia County was estimated at 15.6 cases among 100,000 adults (95%CI 11.8-19.4). The prevalence of SSc in Split-Dalmatia County in Southern Croatia according only to the ACR criteria is higher than in other European countries. These data should facilitate research regarding the role of geographic and environmental factors for this disease in comparison populations.

5HT2A polymorphism His452Tyr in a German Caucasian systemic sclerosis population – authors' response

The variance of results between our recent article [1] and the replication study by Kirsten and colleagues [2] in German patients may prompt the reader to ask the simple question: what conclusion can be drawn from these contradictory results? One possible answer is that one of the two studies is wrong and all the clues would indicate the first report as the one describing a spurious finding. This is consistent with a general overestimate of the role of a gene in the first association study of it [3] and, indeed, we have always been aware of the possibility of false positive findings. Hence, we provided the reader a mean (for example, the false probability report probability) with which to gauge the strength of the association and the chance of having described a spurious result [1]. A second possible answer is that the variance of results stems from methodological differences between the two studies. It has been argued that replication studies should be viewed as tools to uncover heterogeneity rather than tools to test the hypothesis generated by the initial association [3] and, in a more extreme view, the relevance of replication has been questioned [4]. Our and Kirsten and colleagues' studies are heterogeneous with regard to many aspects, starting with 'phenotype definition'. In our report we included only patients fulfilling the American College of Rheumatology criteria for the classification of systemic sclerosis (SSc), while Kristen and colleagues also included 19% of early SSc patients according to LeRoy's definition [5]; we also had 75% limited cutaneous SSc patients compared to 50% in the German population. This different phenotype definition implies that the sets of causative loci or traits underlying the different definitions are likely to be different [3]. Moreover, the prevalence of females in our population was much higher (93.9% versus 50%) and it is well-known that platelets differently aggregate in males and females due to hormonal and gender-specific influences [6]. As we hypothesized that the rs6314 polymorphism does not act as a causative genetic mutation per se, but rather it is important in amplifying SSc-causative and coagulative pathological processes once they have already been triggered by other factors [1], all the above-mentioned and other hidden differences in the genetic background are likely to be of particular relevance. In this sense, it is reductive to consider the importance of the studied single nucleotide polymorphism on SSc susceptibility only for its main independent effect, but it should more appropriately be viewed in the context of a broader gene-gene or gene-environmental frame.

Systemic Sclerosis in Northwestern Spain

To investigate the epidemiology of systemic sclerosis (SSc) in southern Europe, we assessed the incidence, prevalence, clinical spectrum, and survival of patients diagnosed with SSc in the Lugo region of northwestern Spain. Between January 1988 and December 2006, SSc was diagnosed in 78 Lugo residents according to the criteria proposed by LeRoy and Medsger and/or the 1980 American College of Rheumatology (ACR) preliminary criteria for the classification of SSc. However, only 44 (56.4%) of the 78 patients fulfilled the 1980 ACR criteria for the classification of SSc. The mean age at the time of disease diagnosis was 59.8 +/- 13.3 years. Twenty-three (29.5%) met definitions for diffuse SSc (dSSc), and 55 (70.5%) for limited SSc (lSSc). Patients with lSSc had a longer disease duration before the diagnosis (10.2 +/- 12.0 yr) than those with dSSc (3.7 +/- 3.2yr) (p < 0.001). Based on the criteria proposed by LeRoy and Medsger and/or the 1980 ACR criteria for the classification of SSc, the overall age- and sex-adjusted annual incidence rate over the 19-year study period was 2.3 (95% confidence interval [CI], 1.6-2.5) per 100,000 population aged 15 yr and older (women: 3.5 [95% CI, 2.3-3.9]; men: 1.0 [95% CI, 0.5-1.4]; p < 0.001). Using only the 1980 ACR criteria for SSc, the total annual-adjusted incidence rate was 1.2 (95% CI, 0.9-1.6) per 100,000 population aged 15 years and older (women: 1.8 [95% CI, 1.2-2.5]; men: 0.7 [95% CI, 0.3-1.2]; p < 0.001). The incidence increased significantly in individuals aged 45 years or older. The overall incidence rates of SSc increased over the length of the study (p for trend in the total incidence < 0.001). This was mainly due to a progressive increase of SSc in women between 1993 and 2002. By December 31, 2006, the overall age-adjusted SSc prevalence in the Lugo region of patients who met the criteria proposed by LeRoy and Medsger and/or the 1980 ACR criteria was 27.7 (95% CI, 21.1-35.84) per 100,000 population aged 15 years and older. Cardiopulmonary complications were the leading cause of death (13 of 20 cases). Compared with that in the general population, the probability of survival in patients with SSc was significantly reduced (p < 0.001).The current study establishes a baseline estimate of the incidence and clinical spectrum of SSc in northwestern Spain. According to our results, the incidence and prevalence of SSc in northwestern Spain are similar to those found in Greece and some regions of the United States. Our data confirm a reduced probability of survival in patients with SSc.

Pericardial Abnormalities Predict the Presence of Echocardiographically Defined Pulmonary Arterial Hypertension in Systemic Sclerosis-Related Interstitial Lung Disease

To determine the prevalence and significance of pericardial abnormalities in systemic sclerosis (SSc)-related interstitial lung disease (ILD). Retrospective study of 41 subjects with SSc-related ILD who underwent evaluation including thoracic high-resolution CT (HRCT) imaging, transthoracic echocardiography (TTE), and pulmonary function testing. HRCT review evaluated the pericardium for the presence of pericardial effusion (PEf), thickness of the anterior pericardial recess (APR) [abnormal defined as > 10 mm], and pericardial thickening as calculated by total pericardial score (TPS) [abnormal defined as > 8 mm]. Pulmonary arterial hypertension (PAH) was defined as a pulmonary artery pressure > 35 mm Hg estimated by TTE. Fifty-nine percent had an abnormal pericardium, 49% had a PEf, 56% had an abnormal APR, and 49% had an abnormal TPS. An abnormal pericardium was more common in men than women. Subjects with and without pericardial abnormalities were otherwise similar with respect to age, SSc classification, autoantibodies, ILD radiographic pattern, and presence of esophageal dilation. Both groups had similar median percentage of predicted total lung capacity, percentage of predicted FVC, percentage of predicted FEV(1), and percentage of predicted diffusion capacity of the lung for carbon monoxide. Subjects with pericardial abnormalities were more likely to have coexistent PAH (35% vs 75%; p = 0.02) and a higher median right ventricular systolic pressure (31 mm Hg vs 44 mm Hg; p = 0.03). Multiple logistic regression revealed that TPS was the best individual predictor of the presence of TTE-defined PAH. In patients with SSc-related ILD, pericardial abnormalities are commonly seen on HRCT, and their presence is strongly associated with echocardiographically defined PAH, with abnormal TPS as the best individual predictor.

Renal angiographic findings in systemic sclerosis: ‘the Egyptian experience’

AbstractObjective: This study was designed to search for a possible pathological involvement of renal arteries among patients with systemic sclerosis (SSc) and to correlate the findings with renal functions.Patients and methods: Fourteen female patients with SSc were recruited for this study. The diagnosis and classification of SSc was based on the 1980 American College of Rheumatology criteria for classification of SSc. Nine patients had diffuse‐type SSc, and the remaining five belonged to the limited type of the disease. All patients were evaluated by history‐taking, clinical examination, laboratory investigations and renal angiography.Results: Three out of the nine patients (33.3%) with diffuse SSc had tortuous renal arteries, but there were none in the limited type. Two patients (22.2%) with diffuse SSc had ectatic renal arteries and three (33.3%) had osteal renal artery stenosis. Tortuous abdominal aorta was detected in one patient (11.1%) with diffuse SSc and congenital double renal artery in another (11.1%). Two out of the five patients with limited‐type disease (40%) had osteal renal artery stenosis that was bilateral in one case. Bilateral renal artery affection was observed in 3/14 studied patients (21.42%), and two of these had diffuse disease and one had limited disease. Three patients had hypertension (two had diffuse pattern and one had limited pattern).Conclusion: We consider that renal artery stenosis is the most important among all the findings detected and should be considered in SSc patients presenting with renal crisis because use of angiotensin converting enzyme (ACE) inhibitors in this situation may be deleterious rather than beneficial.

The Pediatric Rheumatology European Society/American College of Rheumatology/European League against Rheumatism provisional classification criteria for juvenile systemic sclerosis

To develop criteria for the classification of systemic sclerosis (SSc) in children (juvenile SSc). The study consisted of 3 phases: 1) collection of data on the signs and symptoms of actual patients with juvenile SSc that are useful for defining involvement of a particular organ; 2) selection of the parameters essential for the classification of juvenile SSc and preparation of a set of provisional classification criteria (PCC) using 2 Delphi surveys; 3) consensus conference consisting of 2 steps: discussion and rating of clinical profiles of 160 patients with definite juvenile SSc, possible juvenile SSc, or other fibrosing diseases as "having or not having juvenile SSc," using nominal group technique, and defining those PCC with the best statistical performance and highest face validity by using the clinical profiles of patients with definite juvenile SSc as the gold standard. In phase 1, 55 centers submitted clinical data on 153 patients with juvenile SSc. A total of 48 signs and symptoms were derived from these patient data and were used to define 9 organ system categories (cutaneous, vascular, gastrointestinal, respiratory, renal, cardiac, neurologic, musculoskeletal, and serologic). During phase 2, these were reduced to 21 criteria (3 major criteria [Raynaud's phenomenon, proximal skin sclerosis/induration of the skin, and sclerodactyly] and 18 minor criteria) and combined to generate 86 different PCC. At the consensus conference, these 86 definitions were tested on the case profiles of 127 patients with juvenile SSc. The PCC with the highest ranking were proximal sclerosis/induration and at least 2 minor criteria. These provisional classification criteria for juvenile SSc will help standardize the conduct of clinical research, epidemiologic and outcome studies, and therapeutic trials.

The development of systemic sclerosis classification criteria

Systemic sclerosis (SSc) is a rare connective tissue disorder whose aetiology remains obscure, although environmental and genetic influences are likely to play a role. Disease registries have contributed to enhancing our understanding of this debilitating illness, but without sensitive, specific, and extensively validated classification criteria, accurate comparison between registries and the identification of patients suitable for clinical trials can be problematic. The American College of Rheumatology (ACR) criteria, published in 1980, have become outdated as our understanding of disease specific autoantibodies and nailfold capillaroscopy has improved. In addition, the sensitivity of the ACR criteria is low with respect to limited SSc. Although subsequent classification systems have been proposed, none has gained universal approval. The two- versus three-subset disease model remains a point of debate. Newly derived criteria are likely to draw upon the older classification systems as well as incorporating up-to-date diagnostic techniques and biomarkers. Validation will be critical before their use becomes widespread.

Association of the PTPN22 R620W polymorphism with anti–topoisomerase I– and anticentromere antibody–positive systemic sclerosis

To determine any associations of the PTPN22 R620W single-nucleotide polymorphism (SNP) with systemic sclerosis (SSc) or with anticentromere antibody (ACA)-positive or anti-topoisomerase I (anti-topo I) antibody-positive SSc, in a case-control study of US white, black, Hispanic, and Choctaw Indian individuals. A total of 850 white, 130 black, 120 Hispanic, and 20 Choctaw Indian patients with SSc were compared with 430 white, 164 black, 146 Hispanic, and 76 Choctaw Indian control subjects, respectively. All subjects were living in the US. PTPN22 SNP (rs2476601) genotyping was performed by TaqMan 5' allelic discrimination assay and pyrosequencing. The PTPN22 CT/TT genotype showed significant association with anti-topo I antibody-positive SSc in white patients (odds ratio [OR] 2.21, 95% confidence interval [95% CI] 1.3-3.7) and with ACA-positive white patients with SSc (OR 1.70, 95% CI 1.1-2.7). Frequency of the PTPN22*T allele also showed significant association with anti-topo I antibody-positive SSc in white patients (OR 2.03, 95% CI 1.3-3.2). When data for patients in the 3 ethnic groups (black, white, and Hispanic) were combined, a significant association with both genotype and allele frequencies was observed, suggesting a trend toward association in ACA-positive and anti-topo I antibody-positive SSc. Stepwise logistic regression analysis (controlled for the confounding effects of sex and race) showed that the PTPN22 CT/TT genotype was associated with a significantly higher risk of SSc compared with the CC genotype (for patients with SSc, OR 1.64, 95% CI 1.2-2.2; for ACA-positive patients with SSc, OR 1.63, 95% CI 1.0-2.6; for anti-topo I antibody-positive SSc, OR 2.33, 95% CI 1.5-3.7). Our results indicate that the PTPN22 R620W polymorphism is associated with ACA-positive and anti-topo I antibody-positive subsets of SSc and represents a risk factor in both white patients and black patients. The association of subsets of SSc with the PTPN22 R620W polymorphism further strengthens the classification of SSc within the spectrum of autoimmune diseases and strongly suggests the involvement of common susceptibility genes and similarly disordered immunoregulatory pathways.

Systemische Sklerose – Diagnose und Klassifikation

Systemic sclerosis (SSc) is a polymorphic and heterogenic systemic disorder with inflammation, fibrosis and vascular damage. Early diagnosis and classification may be difficult if disease expression is oligosymptomatic (undifferentiated), presenting with only Raynaud's phenomenon or limited scleroderma. Scleroderma specific antinuclear autoantibodies, which are present early and persistently in about 90% of the patients with SSc, play an important taxonomic role. Scleroderma specific findings in nailfold capillary microscopy are sensitive and predictive for evolving SSc. An algorithm will be presented for the diagnosis and classification of SSc using clinical, capillaroscopic and serologic criteria, which are also useful for mixed or special forms of SSc. The 6th Outcome Measures in Rheumatology Clinical Trials (OMERACT) conference proposed different outcome measurements for clinical studies, however, for daily clinical practice there is as yet no consensus on status indices for disease activity, disease related damage or suitable prognostic criteria.

Classification of systemic sclerosis. Visions and reality**Dedicated to the memory of E. Carwile LeRoy, 1933–2002.

Systemic sclerosis, scleroderma (SSc) is a disabling condition that shortens life expectancy. Disease heterogeneity and difficulties separating SSc from SSc-like conditions make classification an important issue. Limited cutaneous and diffuse cutaneous SSc, with different severity and survival, have been recognized for several years as distinct subsets. Some authors have suggested an intermediate cutaneous form with intermediate survival. This issue remains unsettled, however. The technique of capillaroscopy is helpful as an adjunct diagnostic tool to separate idiopathic Raynaud's phenomenon from SSc. Digitized video-capillaroscopy is developing as a powerful new method to assess individual capillaries over time. Using the simpler techniques of video-capillaroscopy, different patterns have been described and named 'early', 'active', 'late' and 'slow'. The value of nailfold video-capillaroscopy to distinguish different subsets or provide prognostic information for use in daily practice remains to be assessed. The features of CREST (calcinosis, Raynaud's, oesophagus dysmotility, sclerodactyly, telangiectasias) are not confined to single subsets of SSc. There is no convincing evidence of any advantage for distinguishing the limited, intermediate and diffuse forms of SSc rather than only the limited and diffuse forms.

Classification of systemic sclerosis in the Japanese population based on rapid progression of skin thickening

In general, patients with systemic sclerosis (SSc) have been classified in two clinical subsets (diffuse and limited) based on the extent of skin thickening, and the extent of skin fibrosis is closely related to the severity of organ involvement and mortality rates. In addition, there is a rapid progression of skin thickening in diffuse cutaneous SSc (dcSSc). In this study, we classified a novel subset of SSc based on the rate of skin thickening progression, and evaluated the relationship of the subset to disease severity and laboratory markers. Thirty-three patients with dcSSc were included in the study. Participants who had a modified Rodnan's total skin thickness score higher than 15 points within a year from the first symptoms were defined as having rapidly progressive SSc (RPSSc; group 1), while all the other dcSSc patients were defined as having non-RPSSc (group 2). The frequencies of interstitial lung disease and renal crisis were significantly higher in group 1 than in group 2. The frequencies of anti-topoisomerase I antibody (anti-topo I) and anti-SS-A antibody were significantly higher in group 1 than in group 2. Conversely, the frequency of anticentromere antibody was significantly higher in group 2 than in group 1. This study demonstrates the clinical significance of a new subset of SSc (defined as RPSSc), which is characterized by a markedly rapid progression of skin thickening. This new classification may be useful for predicting the prognosis of SSc at an early stage, so that patients who should receive aggressive therapy with immunosuppressants might be identified.

Classification of systemic sclerosis in the Japanese population based on rapid progression of skin thickening

In general, patients with systemic sclerosis (SSc) have been classified in two clinical subsets (diffuse and limited) based on the extent of skin thickening, and the extent of skin fibrosis is closely related to the severity of organ involvement and mortality rates. In addition, there is a rapid progression of skin thickening in diffuse cutaneous SSc (dcSSc). In this study, we classified a novel subset of SSc based on the rate of skin thickening progression, and evaluated the relationship of the subset to disease severity and laboratory markers. Thirty-three patients with dcSSc were included in the study. Participants who had a modified Rodnan’s total skin thickness score higher than 15 points within a year from the first symptoms were defined as having rapidly progressive SSc (RPSSc; group 1), while all the other dcSSc patients were defined as having non-RPSSc (group 2). The frequencies of interstitial lung disease and renal crisis were significantly higher in group 1 than in group 2. The frequencies of antitopoisomerase I antibody (anti-topo I) and anti-SS-A antibody were significantly higher in group 1 than in group 2. Conversely, the frequency of anticentromere antibody was significantly higher in group 2 than in group 1. This study demonstrates the clinical significance of a new subset of SSc (defined as RPSSc), which is characterized by a markedly rapid progression of skin thickening. This new classification may be useful for predicting the prognosis of SSc at an early stage, so that patients who should receive aggressive therapy with immunosuppressants might be identified.

Serum Xylosyltransferase: a New Biochemical Marker of the Sclerotic Process in Systemic Sclerosis

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

Cutaneous Responses to Endothelin-1 and Histamine in Patients with Vibration White Finger

Vibration white finger (VWF) is the episodic blanching of the fingers that occurs in response to cold in those who work with hand-held vibrating tools. Clinically the condition differs from primary Raynaud's phenomenon as persistent pain and paresthesia are common in the hands and arms and occur independently of the "white attacks." We have previously reported a decrease in protein gene product 9.5 and calcitonin gene-related peptide-immunoreactive nerve fibers in the digital skin of individuals with VWF. In this study, we have sought to determine whether this deficit of immunoreactive sensory-motor nerves has a functional counterpart in vivo. Histamine produces a rapid wheal and flare response following intradermal injection, whereas endothelin-1 (ET-1) produces a central area of pallor with a surrounding neurogenic flare. In contrast, calcitonin gene-related peptide produces a non-neurogenic erythema. In this study, histamine and ET-1 were injected into the dorsum of the middle phalanx and the local neurovascular response was assessed by measuring the area of the visible flare or pallor. Basal finger blood flow was also measured by laser Doppler flowmetry in each of the digits prior to intradermal injection. The experiments were performed at 21 degrees C and 4 degrees C. Patients with VWF and asymptomatic vibration-exposed workers had significantly lower resting skin blood flow at both 21 degrees C and 4 degrees C than heavy manual workers with no vibration exposure. The size of the histamine- and ET-1-induced flares at both 21 degrees C and 4 degrees C was significantly smaller in patients with VWF when compared with the asymptomatic vibration-exposed workers and heavy manual workers. The size of the ET-1-induced pallor was smaller in patients with VWF when compared with the heavy manual workers at both 21 degrees C and 4 degrees C. In contrast, the area of erythema induced by intradermal injection of calcitonin gene-related peptide at both 21 degrees C and 4 degrees C was of a similar size in patients with VWF and in heavy manual workers. These results indicate that the neuroneal deficit identified by immunohistochemistry in the digital skin of patients with VWF has a functional counterpart in vivo and is evident as a reduced ability to propagate an axon-reflex vasodilator response when challenged with histamine and ET-1. Furthermore, these results enable patients with VWF to be differentiated from both asymptomatic vibration-exposed workers, in whom the histamine- and ET-1-induced flares are normal, and those with primary Raynaud's disease, in whom the ET-1 flare is reduced and the histamine-induced flare is normal.

Cardiorespiratory Responses to Incremental Exercise in Patients With Systemic Sclerosis

Patients with systemic sclerosis are known to have histologic pulmonary abnormalities despite normal chest radiograph or conventional pulmonary function or both. In an attempt to detect early features of lung involvement in progressive systemic sclerosis, we investigated patients with systemic sclerosis using cardiopulmonary exercise testing. We have studied 78 patients who fulfilled the American Rheumatism Association criteria for the classification of systemic sclerosis, and according to the classification of LeRoy, 44 had limited cutaneous systemic sclerosis and 34 had diffuse cutaneous systemic sclerosis. A significantly decreased diffusing capacity (65 +/- 3% of that predicted) was present only in the group with diffuse cutaneous systemic sclerosis. The patients with lung involvement showed a significant reduction in exercise capacity (54 +/- 3% of that predicted) and in oxygen uptake (70 +/- 3% of that predicted). Additionally, we could demonstrate an increased functional dead space ventilation (0.34 +/- 0.02) and widened alveolar-arterial oxygen difference during exercise (44 +/- 3 mm Hg). By cardiopulmonary exercise testing, 12 of the 78 patients (15%) with normal single-breath diffusing capacity for carbon monoxide had increased dead space to tidal volume ratio. Our results suggest that occult pulmonary impairment may be present in patients with normal pulmonary function and that cardiopulmonary exercise testing enables detection of such impairment. Our study results show the limitations of resting data in predicting abnormalities during exercise in patients with systemic sclerosis.

Classification of systemic sclerosis

Classification of systemic sclerosis

Preliminary criteria for the classification of systemic sclerosis (scleroderma). Subcommittee for scleroderma criteria of the American Rheumatism Association Diagnostic and Therapeutic Criteria Committee.

A multicenter, ongoing study of early-diagnosed cases of systemic sclerosis and comparison patients with systemic lupus erythematosus, polymyositis/dermatomyositis, and Raynaud's phenomenon was conducted in order to develop classification criteria for systemic sclerosis. Preliminary criteria are proposed namely, the finding of either the sole major criterion, i.e., proximal scleroderma, or two or more of the minor criteria, i.e., 1) sclerodactyly, 2) digital pitting scars of fingertips or loss of substance of the distal finger pad, and 3) bilateral basilar pulmonary fibrosis. When applied to the case and comparison patients included in this study, these proposed criteria had a 97% sensitivity for definite systemic sclerosis and 98% specificity.