A multicentre study in the prospective EULAR scleroderma trials and research (EUSTAR) database
Objective: To assess patients with SSc who present without circulating antinuclear antibodies (ANA) or Raynaud’s phenomenon (RP). Methods: 5390 patients who fulfilled the ACR criteria for SSc and were enrolled in the EULAR Scleroderma Trials And Research (EUSTAR) database were screened for the absence of both RP and circulating ANA. To differentiate SSc from its mimics, additional information was gathered using a standardized questionnaire. Results: 5378 (99.8%) of the 5390 SSc patients in the EUSTAR database had either detectable ANA or a history of RP. Twelve patients (0.2%) lacked both circulating ANA and RP. Details of the medical history could be obtained for six patients. Three cases were compatible with ANA-negative and RP-negative SSc and were not typical of any known SSc mimic. Four patients had a malignancy: two had breast cancer, one had multiple myeloma with possible scleromyxoedema, and one had bladder carcinoma. There was no temporal relationship between the onset of skin fibrosis and that of the tumor. Although no patient with confirmed nephrogenic systemic fibrosis (NSF) was identified among the cases of ANA-negative and RP-negative SSc, the presentation of one patient could be compatible with that of NSF other than for the absence of chronic kidney disease or of known prior gadolinium exposure. Conclusion: We have identified a very small subgroup of SSc patients who lack both circulating ANA-and RP, none of whom fulfils the diagnostic criteria for any known SSc mimic. Prospective studies are needed to elucidate the clinical presentation, evolution, and outcome of such patients.