Clements PJ, Hurwitz EL, Wong WK, Seibold JR, Mayes M, White B, et al. Skin thickness score as a predictor and correlate of outcome in systemic sclerosis: high-dose versus low-dose penicillamine trial. Arthritis Rheum. 2000;43:2445-54.
Shand L, Lunt M, Nihtyanova S, Hoseini M, Silman A, Black CM, et al. Relationship between change in skin score and disease outcome in diffuse cutaneous systemic sclerosis: application of a latent linear trajectory model. Arthritis Rheum. 2007;56:2422-31.
Furst DE, Clements PJ. Hypothesis for the pathogenesis of systemic sclerosis. J Rheumatol Suppl. 1997;48:53-7.
Krieg T, Perlish JS, Fleischmajer R, Braun-Falco O. Collagen synthesis in scleroderma: selection of fibroblast populations during subcultures. Arch Dermatol Res. 1985;277:373-6.
Marks RM, Roche WR, Czerniecki M, Penny R, Nelson DS. Mast cell granules cause proliferation of human microvascular endothelial cells. Lab Invest. 1986;55(3):289-94.
Lichtbroun AS, Sandhaus LM, Giorno RC, Kim H, Seibold JR. Myocardial mast cells in systemic sclerosis: a report of three fatal cases. Am J Med. 1990;89:372-6.
Hawkins RA, Claman HN, Clark RA, Steigerwald JC. Increased dermal mast cell populations in progressive systemic sclerosis: a link in chronic fibrosis? Ann Intern Med. 1985;102:182-6. Yamamoto T, Katayama I, Nishioka K. Expression of stem cell factor in the lesional skin of systemic sclerosis. Dermatology. 1998;197:109-14.
Kahari VM, Sandberg M, Kalimo H, Vuorio T, Vuorio E. Identification of fibroblasts responsible for increased collagen production in localized scleroderma by in situ hybridization. J Invest Dermatol. 1988;90:664-70.
Garbuzenko E, Nagler A, Pickholtz D, Gillery P, Reich R, Maquart FX, et al. Human mast cells stimulate fibroblast proliferation, collagen synthesis and lattice contraction: a direct role for mast cells in skin fibrosis. Clin Exp Allergy. 2002;32:237-46.
Hugle T, Hogan V, White KE, van Laar JM. Mast cells are a source of transforming growth factor beta in systemic sclerosis. Arthritis Rheum. 2011;63:795-9.
LeRoy EC, Medsger TA, Jr. Criteria for the classification of early systemic sclerosis. J Rheumatol. 2001;28:1573-6.
Clements PJ, Lachenbruch PA, Seibold JR, Zee B, Steen VD, Brennan P, et al. Skin thickness score in systemic sclerosis: an assessment of interobserver variability in 3 independent studies. J Rheumatol. 1993;20:1892-6.
LeRoy EC, Black C, Fleischmajer R, Jablonska S, Krieg T, Medsger TA, Jr., et al. Scleroderma (systemic sclerosis): classification, subsets and pathogenesis. J Rheumatol. 1988;15:202-5.
Seibold JR, Giorno RC, Claman HN. Dermal mast cell degranulation in systemic sclerosis. Arthritis Rheum. 1990;33:1702-9.
Irani AM, Gruber BL, Kaufman LD, Kahaleh MB, Schwartz LB. Mast cell changes in scleroderma. Presence of MCT cells in the skin and evidence of mast cell activation. Arthritis Rheum. 1992;35:933-9.
Akimoto S, Ishikawa O, Igarashi Y, Kurosawa M, Miyachi Y. Dermal mast cells in scleroderma: their skin density, tryptase/chymase phenotypes and degranulation. Br J Dermatol. 1998;138:399-406.
Falanga V, Soter NA, Altman RD, Kerdel FA. Elevated plasma histamine levels in systemic sclerosis (scleroderma). Arch Dermatol. 1990;126:336-8.
Walker M, Harley R, Maize J, DeLustro F, LeRoy EC. Mast cells and their degranulation in the Tsk mouse model of scleroderma. Proc Soc Exp Biol Med. 1985;180:323-8.
Shiota N, Kakizoe E, Shimoura K, Tanaka T, Okunishi H. Effect of mast cell chymase inhibitor on the development of scleroderma in tight-skin mice. Br J Pharmacol. 2005;145:424-31.
Choi KL, Claman HN. Mast cells, fibroblasts, and fibrosis. New clues to the riddle of mast cells. Immunol Res. 1987;6:145-52.
Yamamoto T, Hartmann K, Eckes B, Krieg T. Role of stem cell factor and monocyte chemoattractant protein-1 in the interaction between fibroblasts and mast cells in fibrosis. J Dermatol Sci.
Okayama Y, Kawakami T. Development, migration, and survival of mast cells. Immunol Res. 2006;34:97-115.
Campbell PM, LeRoy EC. Pathogenesis of systemic sclerosis: a vascular hypothesis. Semin Arthritis Rheum. 1975;4:351-68.
Trotta F, Biagini G, Cenacchi G, Ballardini G, Varotti C, Passarini B, et al. Microvascular changes in progressive systemic sclerosis: immunohistochemical and ultrastructural study. Clin Exp Rheumatol. 1984;2:209-15.
Gulliksson M, Carvalho RF, Ulleras E, Nilsson G. Mast cell survival and mediator secretion in response to hypoxia. PLoS One. 2010;5:e12360.
Maxova H, Bacakova L, Lisa V, Novotna J, Tomasova H, Vizek M, et al. Production of proteolytic enzymes in mast cells, fibroblasts, vascular smooth muscle and endothelial cells cultivated under normoxic or hypoxic conditions. Physiol Res. 2010;59:711-9.

Table 1. Clinical features of 46 patients with systemic sclerosis.
Data are mean±SD, number (%) of patients, or range (n-n).
SBP=systolic blood pressure; DBP=diastolic blood pressure; mRSS=modified Rodnan’s skin thickness score.

Age, years 59.7±11.6 (30-80)
Women 38 (82.6)
Systemic blood pressure, mmHg 126.2±22.5 (92-196)
Diastolic blood pressure, mmHg 74.8±14.2 (48-119)
Disease duration, years 2.1±1.8 (0.1-10)
Limited cutaneous SSc 26 (56.5)
Diffuse cutaneous SSc 20 (43.5)
mRSS, 0-51 points 9.2±9.1 (1-40)
Anti-topoisomerase I antibody, positive 12 (26.1)
Anti-centromere antibody, positive 14 (31.8)