title: Clinical and laboratory features of overlap syndromes of idiopathic inflammatory myopathies associated with systemic lupus erythematosus, systemic sclerosis, or rheumatoid arthritis.
abstract: Because overlap syndromes (OSs) are rarely described, we analyzed retrospectively their frequencies and correlations in Brazilian series of 31 patients with dermatomyositis (DM)/polymyositis (PM) associated with systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or rheumatoid arthritis (RA) attended at a referral single center. Myositis-specific autoantibodies (MSAs: anti-Jo-1, anti-PL-7, anti-PL-12, anti-EJ, anti-OJ, anti-SRP, anti-Mi-2) and myositis-associated autoantibodies (MAAs: anti-PM-Scl75, anti-PM-Scl100, anti-Ku) as well as specific autoantibodies related to SLE, SSc, and RA were investigated. The mean age of the OS patients (9 DM and 22 PM) was 44.6 ± 15.4 years, with a predominance of women (83.9 %) and white ethnicity (58.1 %). PM was the most frequent inflammatory myopathy, and the clinical presentation of DM/PM was significantly different among the OS groups. Overlap was found with SSc (48.4 %), SLE (29.0 %), and RA (22.6 %). The clinical manifestations of DM/PM were identified simultaneously with SSc and RA in the majority of cases, in contrast to identification in the SLE group (p < 0.05). All patients were positive for antinuclear antibodies, and the prevalence of MSA and MAA was 38.8 % in all OS groups, mutually exclusive, and more frequent in the SSc group. Comparing the clinical and laboratory features, there was a higher frequency of vascular (skin ulcers, Raynaud's phenomenon) and pulmonary (interstitial lung disease) involvement in the SSc group (p < 0.05). Moreover, there were no differences among the groups in relation to disease relapse and deaths. Concluding, this is the first study to show the different characteristics of a series of patients with connective tissue disease (CTD)-OS in the heterogeneous Brazilian population.
authors.affiliation: Rheumatology Division, Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Arnaldo, 455 - 3 andar - sala 3190, São Paulo, 01246-903, Brazil.
authors.forename: Lisbeth Aranbicia
authors.initials: LA
authors.lastname: Aguila
authors.forename: Michelle Remião Ugolini
authors.initials: MR
authors.lastname: Lopes
authors.forename: Flavia Zon
authors.initials: FZ
authors.lastname: Pretti
authors.forename: Percival Degrava
authors.initials: PD
authors.lastname: Sampaio-Barros
authors.forename: Fernando Henrique
authors.initials: FH
authors.lastname: Carlos de Souza
authors.forename: Eduardo Ferreira
authors.initials: EF
authors.lastname: Borba
authors.forename: Samuel Katsuyuki
authors.initials: SK
authors.lastname: Shinjo
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000276:immunology; D001323:Autoantibodies; D001938:Brazil; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000150:complications* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009220:Myositis / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D012189:Retrospective Studies; D012595:Scleroderma, Systemic / Q000150:complications* / Q000276:immunology; D012720:Severity of Illness Index; D013577:Syndrome
chemical_list: D001323:Autoantibodies