Endometriosis and systemic lupus erythematosus: a comparative evaluation of clinical manifestations and serological autoimmune phenomena.
OBJECTIVE
In view of evidences suggesting association between endometriosis (EM) and systemic lupus erythematosus (SLE), we have performed a comparative evaluation of clinical and humoral immunologic abnormalities in both diseases.


METHODS
Forty-five women (18-40 years) with histologically confirmed pelvic EM, 21 healthy-women and 15 female SLE-patients (18-40 years) without surgically confirmed EM were prospectively evaluated. Immunologic investigations were performed by blinded researchers.


RESULTS
None of the EM-patients fulfilled criteria for SLE. However, EM-patients presented higher frequencies of arthralgia (62%) and generalized myalgia (18%) superior than normal-controls (24%, P = 0.004/0%, P = 0.048) but comparable with SLE-patients (33%, P = 0.052/27%, P = 0.5). Similarly to SLE (7%), 9% of EM-patients presented fibromyalgia. Antinuclear antibodies (ANA) were detected in 18% of EM-sera, as compared with healthy-women (0%, P = 0.014) and SLE-patients (93%, P = 0.0005). In contrast with SLE, antibodies to dsDNA, Sm and U1RNP were negative in EM-sera. Anti-Ro and anticardiolipin antibodies were more often in SLE (40%, 33%) than in EM-patients (2%, P < 0.001/9%, P = 0.04). Elevated immune-complexes and low total complement were more frequent in SLE (40%, 13%) compared with EM-sera (7%, P = 0.005/0%, P = 0.01).


CONCLUSIONS
Our data indicate differences of ANA antigenic specificity and complement consumption between EM and SLE. The high prevalence of generalized musculoskeletal complaints in EM justifies a multidisciplinary approach.
Pasoto
Sandra G
SG
Rheumatology Division, Medical School, University of São Paulo, São Paulo, Brazil. reumato@edu.usp.br
Abrao
Mauricio S
MS
Viana
Vilma S T
VS
Bueno
Cleonice
C
Leon
Elaine P
EP
Bonfa
Eloisa
E
D000293:Adolescent; D000328:Adult; D017153:Antibodies, Anticardiolipin / Q000097:blood; D000974:Antibodies, Antinuclear / Q000097:blood; D001168:Arthritis / Q000097:blood / Q000276:immunology; D024402:Carbonic Anhydrase II / Q000276:immunology; D003165:Complement System Proteins / Q000276:immunology; D003710:Demography; D004311:Double-Blind Method; D004715:Endometriosis / Q000175:diagnosis / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D005260:Female; D005356:Fibromyalgia / Q000097:blood / Q000276:immunology; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis / Q000276:immunology*; D011446:Prospective Studies; D012217:Rheumatoid Factor / Q000097:blood; D012698:Serologic Tests
D017153:Antibodies, Anticardiolipin; D000974:Antibodies, Antinuclear; D000939:Epitopes; D003165:Complement System Proteins; D012217:Rheumatoid Factor; D024402:Carbonic Anhydrase II