The frequency of anti-DFS70 autoantibodies in Japanese women with peri-and postmenopausal arthralgia.

Abstract

Background: The antinuclear antibody (ANA) test is often used as a screening test to aid in the diagnosis of systemic lupus erythematous (SLE and other systemic autoimmune rheumatic diseases (SARD). However, recently it was reported that a certain autoantibody referred to as anti-dense fine speckled 70 (DFS70) are much more common (up to 25%) of non-SARD and healthy individuals but rare <5%) in SLE and certain SARD. The frequency of anti-DFS70 is even lower (i.e. <1%) if monospecific anti-DFS70 antibodies are found. Some reports suggested that anti-DFFS70 are more common in younger females, suggesting that hormonal factors may be responsible for the cognate B cell response. Objective(s): The primary objective of our study was to determine the frequency of ant-DFS70 in menopausal women who were referred for evaluation of undifferentiated arthritis (UA). Method(s): 282 women including 105 with UA and an age range of 27~91 years (mean=60.3) were enrolled. Menopausal women were divided into pre-, peri-, and post-menopausal stages according to menstrual regularity. (E2), Follicle stimulating hormone (FSH), rheumatoid factor (RF), ANA (by indirect immunofluorescence (IIF) (MBL) anti-cyclic citrullinated peptide antibody (ACPA: MBL ELISA) and C-reactive protein (CRP) were included in the serology workup. Postmenopausal arthralgia was designated PoMA and perimenopausal arthralgia PeMA. Result(s): In PoMA women who received HRT for two months estradiol levels increased, FSH levels decreased and the joint pain visual analogue scale was reduced by 70%, as compared to baseline. Similarly in PeMA women, administration of 600 mg tocopherol N daily had the same efficacy as that observed in PoMA. The overall frequency of anti-DFS70 of 26.7% (28/105) in PoMA and PeMA women was significantly higher than that in UA females who were diagnosed with rheumatoid arthritis (RA) (7/65:10.8%) or primary Sjogren's syndrome (SjS) (3/31: 9.7%) (p<0.05). In addition, anti-DFS70 Ab was observed primarily in low titer (1:40 -1:160) ANA positive sera. On the other hand, higher titer ANAs (titer >1/320) were observed in the females that were diagnosed as systemic lupus erythematosus (SLE) (30%) or primary SjS (48.4%), the majority of whom had lower titers of anti-DFS70, although several sera contained both high titer ANA and anti-DFS70 (see figure). Conclusion(s): Anti-DFS70 was found in higher frequency in PeMA and PoMA women than in women who developed a defined systemic autoimmune rheumatic disease such as SLE, SjS or RA. This is the first study to suggest that the presence of this autoantibody may reflect oestrogen fluctuations or deficiency. A negative association between ANA titer and anti-DFS70 levels by ELISA remains to be confirmed in larger studies. (Table Presented).