Sarcoidosis and Systemic Sclerosis: Strange Bedfellows

Yu, Micah; Sandhu, Vaneet K.; Lezcano, Sheila D.; Maken, Kanwaljeet; Kirk, Shannon; Torralba, Karina D.

doi:https://doi.org/10.1155/2017/7851652

Case Reports in Rheumatology

On this page

Abstract Introduction Case Report Discussion Conflicts of Interest References Copyright Related Articles

Case Report | Open Access

Volume 2017 | Article ID 7851652 | https://doi.org/10.1155/2017/7851652

Sarcoidosis and Systemic Sclerosis: Strange Bedfellows

Micah Yu,¹Vaneet K. Sandhu,²Sheila D. Lezcano,²Kanwaljeet Maken,³Shannon Kirk,⁴and Karina D. Torralba²

Academic Editor: Tsai-Ching Hsu

Received02 Jun 2017

Accepted27 Jul 2017

Published24 Aug 2017

Abstract

Coexistence of systemic sclerosis and sarcoidosis is rare. Both have predominant lung manifestations, each with distinctive features on computed tomography (CT) of the chest. We present herein a 52-year-old male with limited systemic sclerosis manifested primarily by sclerodactyly and subsequently by shortness of breath. A series of CT scans of the chest were reviewed. Initial CT chest one year prior to sclerodactyly onset revealed bilateral hilar and right paratracheal, prevascular, and subcarinal adenopathy. Five-year follow-up demonstrated thin-walled cysts, mediastinal lymphadenopathy, and nonspecific nodules. Due to progression of dyspnea, follow-up CT chest after one year again demonstrated multiple cysts with peripheral nodularity and subpleural nodules, but no longer with hilar or mediastinal adenopathy. Diagnostic open lung biopsy was significant for noncaseating granulomas suggestive of sarcoidosis. This is the first known case of a patient with systemic sclerosis diagnosed with sarcoidosis through lung biopsy without radiographic evidence of hilar or mediastinal lymphadenopathy at the time of biopsy. A review of cases of concomitant sarcoidosis and systemic sclerosis is discussed, including the pathophysiology of each disease with shared pathways leading to the development of both conditions in one patient.

1. Introduction

Sarcoidosis is a multisystem disease of unknown etiology defined by noncaseating granulomas that may be seen on lung imaging as bilateral hilar lymphadenopathy and/or interstitial lung disease (ILD) [1, 2]. The association of sarcoidosis with other autoimmune diseases may include systemic sclerosis, Hashimoto’s thyroiditis, systemic lupus erythematosus, rheumatoid arthritis, and more [3, 4]. In contrast to findings of mid- to upper-lobe interstitial lung disease (ILD) with hilar lymphadenopathy in sarcoidosis, the most common lung manifestation of systemic sclerosis is lower-lobe ILD, which is typically characterized by a nonspecific interstitial pneumonia pattern (groundglass opaci-ties, pulmonary fibrosis, and honeycomb cysts) [5–7]. We report herein the atypical case of a Caucasian male with systemic sclerosis who was eventually diagnosed with pulmonary sarcoidosis. The pathophysiology of each disease, including shared pathways leading to the development of both conditions, is reviewed in addition to previous reports of patients with concomitant systemic sclerosis and sarcoidosis.

2. Case Report

A 52-year-old Caucasian male presented initially to the Loma Linda University Rheumatology Clinic in 2007 with swelling in the hand and foot joints. He also endorsed a history of dyspnea on exertion; however, due to lack of follow-up after the initial visit, no diagnosis or treatment was provided at the time. Incidental review of chest CT done one year previously through his primary care provider was significant for bilateral hilar and right paratracheal, prevascular, and subcarinal adenopathy. Five years later, the patient presented again to the rheumatology clinic with Raynaud’s phenomenon, fingertip ulcerations, skin thickening and tightness over his fingers, and hypo- and hyperpigmented patches over the lower extremities. He also endorsed shortness of breath but denied mucocutaneous lesions, gastrointestinal manifestations, hair loss, or sicca symptoms. Physical examination confirmed sclerodactyly, fingertip ulcerations, and intermixed hypo- and hyperpigmented skin changes. Despite a normal cardiopulmonary physical examination, chest X-ray implicated interstitial pulmonary fibrosis with nodules noted both in the right upper lobe (5.1 mm) and in the left lower lobe (6.6 mm). Follow-up imaging by high-resolution chest CT (HRCT) confirmed multiple nonspecific nodules in the right upper and middle lobes and bilateral oblique fissures ranging in size from 5 to 9 mm. This was in addition to mediastinal lymphadenopathy and multiple thin-walled air cysts bilaterally with peripheral intralobular groundglass opacities suggestive of lymphocytic interstitial pneumonia (LIP).

On laboratory evaluation, serum antinuclear antibody (1 : 640 centromere pattern, 1 : 160 speckled) and rheumatoid factor (RF), anti-SSA, anti-SSB, and anti-centromere antibodies were positive. C-reactive protein and erythrocyte sedimentation rate were normal. Antibodies to double-stranded DNA (dsDNA), Smith, Scl-70, U1RNP, and cyclic-citrullinated peptide (CCP) were negative. Urinalysis, comprehensive metabolic profile, and angiotensin-converting enzyme (ACE) were normal. Infectious evaluation, including quantiferon testing and histoplasma and coccidioides serologies, was negative. Pulmonary function testing (PFT) revealed an FEV1/FVC ratio of 98% with diffusion capacity of carbon monoxide (DLCO) 71%. This combination of clinical and serologic features yielded a diagnosis of limited systemic sclerosis with interstitial lung disease (ILD).

One year later, the patient endorsed progression of exertional dyspnea in addition to a new onset dry cough. Transthoracic echocardiography revealed a normal ejection fraction (65%) without valvular abnormality or pulmonary hypertension. Follow-up HRCT demonstrated multiple cysts bilaterally with peripheral nodularity and small subpleural nodules. Interestingly, previously noted hilar and mediastinal adenopathy were not present. PFT disclosed likely progression of fibrosis with an FEV1/FVC ratio of 96% and worsened DLCO 63%. Lung biopsies were obtained by way of video-assisted thoracoscopy with right lung wedge resection and mediastinal lymph node dissection. The histologic findings unexpectedly revealed prominent nonnecrotizing granulomatous inflammation of the parenchyma, pleura, and lymph nodes, all of which supported a diagnosis of sarcoidosis.

In this long-term follow-up of a patient initially diagnosed with systemic sclerosis, the subsequent clinical, laboratory, and histologic evaluation yielded an ultimate diagnosis of an overlap syndrome of systemic sclerosis and sarcoidosis with ILD. For this, treatment was initiated with mycophenolate mofetil 500 mg twice daily by mouth in addition to diltiazem 90 mg every 12 hours by mouth for Raynaud’s phenomenon. During follow-up visits thus far, the patient has demonstrated decreased shortness of breath and cough, with objective follow-up (i.e., PFT, 6MWT) examination still pending. Further longitudinal follow-up with the patient is anticipated in addition to reviewing response to therapy by way of follow-up imaging.

3. Discussion

Sarcoidosis and systemic sclerosis are both multisystem disorders of unknown etiology. While sarcoidosis manifests as a noncaseating granulomatous disease affecting most commonly the lungs, skin, and eyes, systemic sclerosis is a connective tissue disorder characterized by cutaneous sclerosis, visceral fibrosis, and vasculopathy. Because the incidence of sarcoidosis is 50 to 400 per million per year and the incidence of systemic sclerosis is 20 per million per year, the likelihood of overlap disease is expected to be low [8]. Other rarely reported autoimmune diseases that have been reported in association with sarcoidosis include rheumatoid arthritis, systemic lupus erythematosus, Sjögren syndrome, and thyroid disease [3, 9].

Enzenauer and West have demonstrated that, of 569 consecutive patients with connective tissue disease, six patients (1%) developed concomitant sarcoidosis over a 10-year period [3]. More specific to the case at hand, while rare, the coexistence of sarcoidosis with systemic sclerosis has been reported in the literature. Of twenty-nine published cases demonstrating an association of systemic sclerosis with sarcoidosis, only 16 were fully accessible. A review of these cases revealed a predominance of females (74%) with an average age of 54 years [2, 3, 10–21]. Histologic evidence by biopsy of the lung was noted in 8 subjects, biopsy of the skin in 6 subjects, and biopsy of the muscle in 1 subject. Most patients with serum Scl-70 antibody were male (78%), while anti-centromere antibodies were typically demonstrated among females (88%), implicating a relationship between autoantibody profiles and gender in the concurrence of these diseases [22].

Sarcoidosis and systemic sclerosis independently demonstrate lung pathology manifested clinically by dyspnea and cough and radiographically by distinct features on CT of the chest. Pulmonary disease in systemic sclerosis is characterized by ILD and/or pulmonary hypertension, both of which are significant causes of morbidity and mortality that necessitate frequent screening. Systemic sclerosis-ILD is typically a nonspecific interstitial pneumonia (NSIP) pattern with groundglass opacities, interstitial pulmonary fibrosis, and honeycomb cystic changes in the lower lung zones [5, 6, 23]. In fact, NSIP is the most common histopathologic diagnosis in systemic sclerosis–related lung disease patients who underwent surgical lung biopsy [6]. In contrast, lung manifestations of sarcoidosis include bilateral hilar and mediastinal lymphadenopathy but may also involve beading or irregular thickening of the bronchovascular bundles, bronchial wall thickening, nodules along the bronchi, blood vessels, subpleural lesions, and mid- to upper-lobe-predominant groundglass opacities identified on HRCT chest [3, 7, 22] and confirmed by biopsy if clinically indicated.

In the case presented, mediastinal and hilar adenopathy were present on the initial two HRCT scans of the chest but not so on the last HRCT done just prior to lung biopsy. Rather, the last two chest HRCT scans revealed cystic changes more suggestive of LIP, which is a nonspecific finding of inflammatory lung disease [23, 24]. Similar to other HRCT findings of sarcoidosis, LIP may demonstrate thickened bronchovascular bundles, nodules, groundglass opacities, cysts, and thickening of interlobular septa [25].

While the pathogenesis of sarcoidosis and systemic sclerosis remains unclear, both diseases occur as a result of immune system activation with a subsequent inflammatory reaction in some genetically predisposed individuals (i.e., mutations, SNPs, and chromosomal aberrations) and others with environmental exposures [26, 27]. With regard to cellular pathophysiology, sarcoidosis is a T-helper 1- (Th1-) mediated disease that results in noncaseating epithelioid cellular granuloma formation [28]. CD4⁺ T-lymphocytes have been identified in the tissues of patients with sarcoidosis and appear to be most concentrated within the granulomatous lesion [29]. Th1 cytokines, interferon- (IFN-) λ and interleukin- (IL-) 2, are elevated in sarcoidosis, while T-helper 2 (Th2) cytokines, IL-4 and IL-5, are decreased [30]. On the other hand, the complex pathophysiology of systemic sclerosis varies based on the stage of the disease. Early and active stages of systemic sclerosis are a result of the Th2 pathway [31], with progression of the disease believed to result from damage of the endothelial lining in small blood vessel walls leading to impaired circulation and subsequent tissue hypoxia and collagen deposition [32]. While this foundation of systemic sclerosis and sarcoidosis pathophysiology is significantly different, both conditions have demonstrated commonalities with regard to cytokines. IL-1α has been implicated as a producer of IL-6, which is elevated in the serum as well as fibroblasts of patients with systemic sclerosis when compared with healthy individuals [33]. It is also found to be higher in the bronchoalveolar lavage fluid of patients with systemic sclerosis, implicating a role in the pulmonary pathogenesis of systemic sclerosis [33]. Similarly, IL-6 and IL-8 were found to be elevated in the bronchoalveolar lavage fluid of patients with active sarcoidosis [34].

Fibrosis is a pathologic attribute shared by both systemic sclerosis and sarcoidosis, specifically with multisystemic fibrosis in systemic sclerosis and a more localized lung fibrosis in 20–25% of patients with sarcoidosis [35]. Both conditions have demonstrated an increased prostaglandin endoperoxidase-2 (PTGS2) or cyclooxygenase-2 (COX-2) expression. In sarcoidosis, a promoter polymorphism, −765G>C, has demonstrated an association with lung fibrosis onset [36, 37]. The cytokine TGF-β1 induces COX-2 expression through smad signaling pathways and is known to drive fibrosis in systemic sclerosis [36]. Experimental use of a neutralizing antibody against TGF-β1 has demonstrated reversal of cutaneous fibrosis in systemic fibrosis [37, 38]. Levels of TGF-β1 are also increased in peripheral blood lymphocytes and bronchoalveolar cells in sarcoidosis patients with lung involvement [36, 38]. TGF-β2 and TGF-β3 gene polymorphisms have been implicated in cutaneous fibrosis of systemic sclerosis [39] with similar findings demonstrated by Kruit and colleagues in a four-year follow-up of sarcoidosis patients developing pulmonary fibrosis when bearing a genetic variation of TGF-β3 [27].

Chemokines are cytokines that are crucial in leukocyte recruitment to inflamed tissues. In a study conducted by Furuse and colleagues, patients with systemic sclerosis demonstrated greater IL-8 and GRO-α that correlated with a decrease in DLCO compared with their counterparts with SLE and type II diabetes [40]. van Bon and colleagues further established that CXCL4 downregulates the antifibrotic cytokine IFN-γ and upregulates the profibrotic cytokines IL-4 and IL-13 [41]. This was demonstrated in patients with high CXCL4 at baseline compared with other biomarkers for systemic sclerosis who experienced a more rapid decline in DLCO, greater prevalence of HRCT-confirmed lung fibrosis, and progressive skin fibrosis [41]. On the other hand, sarcoidosis is associated with increased IFN-γ-inducible chemokines, CXCL9 and CXCL10, which correlate with severity in lung function as measured by DLCO and PFT [42]. These chemokines may be a target for therapeutics in the future.

As there are potentially similar immunopathologic pathways in sarcoidosis and systemic sclerosis, further research on evaluation and management strategies may shed light on improving patient outcomes. We additionally encourage clinicians to engage in a detailed investigation into potential overlapping lung disease in the presence of discordant CT and pathologic findings.

Conflicts of Interest

The authors declare that there are no conflicts of interest.

References

M. C. Ianuzzi, B. A. Rybicki, and A. S. Teirstein, “Sarcoidosis,” New England Journal of Medicine, vol. 357, no. 21, pp. 2153–2165, 2007.
View at: Publisher Site | Google Scholar
H. Groen, D. S. Postma, and C. G. M. Kallenberg, “Interstitial lung disease and myositis in a patient with simultaneously occurring sarcoidosis and scleroderma,” Chest, vol. 104, no. 4, pp. 1298–1300, 1993.
View at: Publisher Site | Google Scholar
R. J. Enzenauer and S. G. West, “Sarcoidosis in autoimmune disease,” Seminars in Arthritis and Rheumatism, vol. 22, no. 1, pp. 1–17, 1992.
View at: Publisher Site | Google Scholar
I. Rubinstein, G. L. Baum, Y. Hiss, S. Margaliot, and A. Yellin, “Sarcoidosis and Hashimoto’s thyroiditis—a chance occurrence?” Respiration, vol. 48, no. 2, pp. 136–139, 1985.
View at: Publisher Site | Google Scholar
J. J. Solomon, A. L. Olson, A. Fischer, T. Bull, K. K. Brown, and G. Raghu, “Scleroderma lung disease,” European Respiratory Review, vol. 22, no. 127, pp. 6–19, 2013.
View at: Publisher Site | Google Scholar
J. G. Goldin, D. A. Lynch, D. C. Strollo et al., “High-resolution CT scan findings in patients with symptomatic scleroderma-related interstitial lung disease,” Chest, vol. 134, no. 2, pp. 358–367, 2008.
View at: Publisher Site | Google Scholar
T. Koyama, H. Ueda, K. Togashi, S. Umeoka, M. Kataoka, and S. Nagai, “Radiologic manifestations of sarcoidosis in various organs,” Radiographics, vol. 24, no. 1, pp. 87–104, 2004.
View at: Publisher Site | Google Scholar
M. D. Mayes, J. V. Lacey Jr., J. Beebe-Dimmer et al., “Prevalence, incidence, survival, and disease characteristics of systemic sclerosis in a large US population,” Arthritis & Rheumatism, vol. 48, no. 8, pp. 2246–2255, 2003.
View at: Publisher Site | Google Scholar
T. Takahashi, M. Munakata, Y. Homma, and Y. Kawakami, “Association of progressive systemic sclerosis with pulmonary sarcoidosis. Just a chance occurrence?” Internal Medicine, vol. 36, no. 6, pp. 435–438, 1997.
View at: Publisher Site | Google Scholar
M. De Bandt, S. Perrot, C. Masson, and O. Meyer, “Systemic sclerosis and sarcoidosis, a report of five cases,” British Journal of Rheumatology, vol. 36, no. 1, pp. 117–119, 1997.
View at: Publisher Site | Google Scholar
H. Suga, Y. Asano, Z. Tamaki et al., “A case of systemic sclerosis with sarcoidosis,” Acta Dermato-Venereologica, vol. 91, no. 6, pp. 718–720, 2011.
View at: Publisher Site | Google Scholar
S. Kobak, F. Sever, O. Sivrikoz, and A. Karaarslan, “Coexistence of sarcoidosis and systemic sclerosis,” Case Reports in Rheumatology, vol. 2013, pp. 1–3, 2013.
View at: Publisher Site | Google Scholar
N. Hosoya, T. Mimura, Y. Enokawa et al., “A rare case of cardiac sarcoidosis in a patient with progressive systemic sclerosis, Sjogren’s syndrome, and polymyositis,” Internal Medicine, vol. 34, no. 12, pp. 1164–1167, 1995.
View at: Publisher Site | Google Scholar
R. Mahajan, R. Jindal, and A. J. Kanwar, “Sarcoidosis associated systemic sclerosis: more than chance occurrence,” Journal of Dermatology, vol. 39, no. 9, pp. 801-802, 2012.
View at: Publisher Site | Google Scholar
T. Yamamoto and Y. Motoki, “Transepidermal elimination of sarcoidal granuloma in a patient with sarcoidosis and systemic sclerosis overlap,” European Journal of Dermatology, vol. 22, no. 15, pp. 286-287, 2012.
View at: Publisher Site | Google Scholar
K. Ogane, T. Kato, I. Mizushima, M. Kawano, and M. Yamagishi, “A case of sarcoidosis developing as sarcoid myopathy concomitant with systemic sclerosis and review of the literature,” Modern Rheumatology, vol. 22, no. 1, pp. 142–146, 2012.
View at: Publisher Site | Google Scholar
N. Sakamoto, Y. Ishimatsu, T. Kakugawa et al., “Sarcoidosis in a patient with systemic sclerosis and primary biliary cirrhosis,” Internal Medicine, vol. 49, no. 15, pp. 1609–1611, 2010.
View at: Publisher Site | Google Scholar
O. P. Sharma and I. Ahamad, “The CREST syndrome and sarcoidosis. Another example of an overlap syndrome,” Sarcoidosis, vol. 5, no. 1, pp. 71–73, 1988.
View at: Google Scholar
J. Borges da Costa, A. Mayer-da-Silva, L. M. Soares de Almeida, and M. Marques Gomes, “Success of prednisone in the treatment of a patient with sarcoidosis and systemic sclerosis: report of a case,” Dermatology Online Journal, vol. 15, no. 3, p. 11, 2009.
View at: Google Scholar
X. X. Ren, S. W. Hou, Z. F. Li et al., “A case of sarcoidosis with systemic sclerosis,” Chinese Medical Journal, vol. 126, p. 4400, 2013.
View at: Publisher Site | Google Scholar
Y. Maekawa and R. Nogami, “A case of progressive systemic sclerosis associated with sarcoidosis and esophageal adenocarcinoma,” Journal of Dermatology, vol. 20, no. 1, pp. 45–48, 1993.
View at: Publisher Site | Google Scholar
S. Senda, K. Igawa, M. Nishioka, H. Murota, and I. Katayama, “Systemic sclerosis with sarcoidosis: case report and review of the published work,” Journal of Dermatology, vol. 41, no. 5, pp. 421–423, 2014.
View at: Publisher Site | Google Scholar
A. Fischer, K. M. Antoniou, K. K. Brown et al., “An official European Respiratory Society/American Thoracic Society research statement: interstitial pneumonia with autoimmune features,” European Respiratory Journal, vol. 46, no. 4, pp. 976–987, 2015.
View at: Publisher Site | Google Scholar
T. S. Panchabhai, C. Farver, and K. B. Highland, “Lymphocytic interstitial pneumonia,” Clinics in Chest Medicine, vol. 37, no. 3, pp. 463–474, 2016.
View at: Publisher Site | Google Scholar
T. Flament, A. Bigot, B. Chaigne, H. Henique, E. Diot, and S. Marchand-Adam, “Pulmonary manifestations of Sjögren’s syndrome,” European Respiratory Review, vol. 25, no. 140, pp. 110–123, 2016.
View at: Publisher Site | Google Scholar
S. Hofmann, A. Franke, A. Fischer et al., “Genome-wide association study identifies ANXA11 as a new susceptibility locus for sarcoidosis,” Nature Genetics, vol. 40, no. 9, pp. 1103–1106, 2008.
View at: Publisher Site | Google Scholar
J. C. A. Broen, T. R. D. J. Radstake, and M. Rossato, “The role of genetics and epigenetics in the pathogenesis of systemic sclerosis,” Nature Reviews Rheumatology, vol. 10, no. 11, pp. 671–681, 2014.
View at: Publisher Site | Google Scholar
G. Smith, I. Brownell, M. Sanchez, and S. Prystowsky, “Advances in the genetics of sarcoidosis,” Clinical Genetics, vol. 73, no. 5, pp. 401–412, 2008.
View at: Publisher Site | Google Scholar
T. Pettersson, “Rheumatic features of sarcoidosis,” Current Opinion in Rheumatology, vol. 10, no. 1, pp. 73–78, 1998.
View at: Publisher Site | Google Scholar
A. Lazarus, “Sarcoidosis: epidemiology, etiology, pathogenesis, and genetics,” Disease-a-Month, vol. 55, no. 11, pp. 649–660, 2009.
View at: Publisher Site | Google Scholar
S. Romagnani, “T-cell subsets (Th1 versus Th2),” Annals of Allergy, Asthma & Immunology, vol. 85, no. 1, pp. 9–18, 2000.
View at: Publisher Site | Google Scholar
J. R. Seibold, “Scleroderma,” in Kelley’s Textbook of Rheumatology, , E. D. Harris, R. C. Budd, G. S. Firestein et al., Eds., Elsevier/Saunders, Philadelphia, PA, USA, 7th edition edition, 2005.
View at: Google Scholar
Y. Kawaguchi, M. Hara, and T. M. Wright, “Endogenous IL-1α from systemic sclerosis fibroblasts induces IL-6 and PDGF-A,” Journal of Clinical Investigation, vol. 103, no. 9, pp. 1253–1260, 1999.
View at: Publisher Site | Google Scholar
R. E. Girgis, M. A. Basha, M. Maliarik, J. Popovich Jr., and M. C. Iannuzzi, “Cytokines in the bronchoalveolar lavage fluid of patients with active pulmonary sarcoidosis,” American Journal of Respiratory and Critical Care Medicine, vol. 152, no. 1, pp. 71–75, 1995.
View at: Publisher Site | Google Scholar
G. W. Hunninghake and R. G. Crystal, “Pulmonary sarcoidosis: a disorder mediated by excess helper T-lymphocyte activity at sites of disease activity,” New England Journal of Medicine, vol. 305, no. 8, pp. 429–434, 1981.
View at: Publisher Site | Google Scholar
W. J. Piotrowski, J. Kiszałkiewicz, D. Pastuszak-Lewandoska et al., “TGF-β and SMADs mRNA expression in pulmonary sarcoidosis,” Advances in Experimental Medicine and Biology, vol. 852, pp. 59–69, 2015.
View at: Publisher Site | Google Scholar
J. Avouac, N. Cagnard, J. H. Distler et al., “Insights into the pathogenesis of systemic sclerosis based on the gene expression profile of progenitor-derived endothelial cells,” Arthritis & Rheumatism, vol. 63, no. 11, pp. 3552–3562, 2011.
View at: Publisher Site | Google Scholar
L. M. Rice, C. M. Padilla, S. R. McLaughlin et al., “Fresolimumab treatment decreases biomarkers and improves clinical symptoms in systemic sclerosis patients,” Journal of Clinical Investigation, vol. 125, no. 7, pp. 2795–2807, 2015.
View at: Publisher Site | Google Scholar
E. Susol, A. L. Rands, A. Herrick et al., “Association of markers for TGFβ3, TGFβ2 and TIMP1 with systemic sclerosis,” Rheumatology, vol. 39, no. 12, pp. 1332–1336, 2000.
View at: Publisher Site | Google Scholar
S. Furuse, H. Fujii, Y. Kaburagi et al., “Serum concentrations of the CXC chemokines interleukin 8 and growth-regulated oncogene-α are elevated in patients with systemic sclerosis,” Journal of Rheumatology, vol. 40, no. 7, pp. 1524–1528, 2003.
View at: Google Scholar
L. van Bon, A. J. Affandi, J. Broen et al., “Proteome-wide analysis and CXCL4 as a biomarker in systemic sclerosis,” New England Journal of Medicine, vol. 370, no. 5, pp. 433–443, 2014.
View at: Publisher Site | Google Scholar
R. Su, M.-L. T. Nguyen, M. R. Agarwal et al., “Interferon-inducible chemokines reflect severity and progression in sarcoidosis,” Respiratory Research, vol. 14, no. 1, p. 121, 2013.
View at: Publisher Site | Google Scholar

Copyright

Copyright © 2017 Micah Yu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

3873

Downloads

1077

Citations