BACKGROUND Systemic sclerosis (SSc) is an autoimmune disease (ADs) that presents with significant morbidity and mortality. When it coexists with one or more AIDs is coined as polyautoimmunity (PAI). It is suggested that PAI modifies the prognosis of SSc. However, the characteristics of presentation of overt PAI in SSc are unknown, as well as the nature and extention in the literature. OBJECTIVE Identify nature, extent and type of evidence of overt PAI in SSc. METHODOLOGY An scope systematic review literature. The MEDLINE, EMBASE, LILACS, SCOPUS, PAHO, gray literature and manual search databases were consulted. Articles that reported SSc and some ADs were included. Results were synthesized by study characteristics, associated ADs, clinical and paraclinical presentation. RESULTS 52 articles were included. The most frequent design was observational studies like case reports and case series (n = 18), the continent with the most publications was Europe (n = 22). The frequency of SSc-PAI was 10% to 43.3%. Discrepancy was evident in the presentation of AIDs coexisting with SSc between countries and continents. Most os patients were women with limited SSc (SScL) suubphenotype. Articles on prognosis of the SSc-PAI were scarce. DISCUSSION It is tempting to speculate that discrepancies of the concomitant ADs with SSc could be associated to environmental and genetic factors, as well as classification criteria used and the type of study. The effect of PAI on the prognosis and treatment of the disease is still unknown. CONCLUSIONS The frequency of SSc-PAI is diverse, and it is most frequent in women with limited subphenotype.
