Arthritis & Rheumatism, Volume 60,
October 2009 Abstract Supplement
The 2009 ACR/ARHP Annual Scientific Meeting
Philadelphia October 16-21, 2009.
ANA-Positive Healthy Individuals and Autoimmune Rheumatic Patients Present Distinctive Pattern and Titer Profiles at the ANA HEp-2 Assay
Mariz1, Henrique A., Rodrigues1, Silvia H., Campos2, Silvia H. B., Ferreira3, Gilda A., Sato1, Emilia I., Andrade1, Luis Eduardo C.
We sought for distinctive ANA HEp-2 features in ANA-positive healthy controls (HC) and patients with autoimmune rheumatic diseases (ARD).
918 HC [32.1±10.3 years old; 634 (69.0%) women], from two large cities in the western southern hemisphere were retrieved among workers in a hydroelectric power plant (n=444) and among blood donors (n=474). HC were defined after a clinical questionnaire to exclude current or past ARD, infections and neoplasia. A subset of the HC group was re-evaluated after 3.6 to 5.0 years (mean 3.9±0.3 years). Sera from 153 randomly selected ARD patients comprised the control group: systemic lupus erythematosus (n=87), systemic sclerosis (n=45), Sjögren's syndrome (n=10), and dermato/polymyositis (n=11). HEp-2 ANA was determined at 1:80 and successive dilutions by two blinded independent observers. ANA-positive sera were screened for antibodies against extractable nuclear antigens (ENA: Sm, U1-RNP, SS-A/Ro, SS-B/La) by double immunodiffusion against calf spleen extract.
ANA was positive in 138 ARD patients (90.2%) and 118 HC (12.8%). ARD patients presented predominantly high titer (>=1:1280) and HC presented essentially low titer (<=1:160) but exceptions did occur (Table 1). ANA pattern profile was distinct in the two groups. Nuclear homogeneous (Ho), nuclear coarse speckled (NCS), centromere, and cytoplasmic dense fine speckled (Cyto DFS) patterns were exclusively observed in ARD patients. Nuclear dense fine speckled (NDFS) pattern was present only in HC. The most frequent ANA pattern in both groups was the nuclear fine speckled (NFS), which occurred at significantly lower titer among HC (median 1:80) as compared to ARD patients (median 1:1280) (p<0.001). Anti-ENA was present in 1 HC (SS-A/Ro) and in 35 (25.3%) ARD patients. At follow-up none of the 40 re-evaluated HC developed ARD and 29 (72.5%) remained ANA-positive. All HC that became ANA-negative had baseline ANA titer of 1:80.
Table 1. Distribution of ANA HEp-2 titer and pattern in HC and ARD patients.
|Titer||HC (%)||ARD (%)||P||Pattern||HC (%)||ARD (%)||P|
|1:80||54 (45.7)||10 (7.3)||<0.001||NCS||0||36 (26.0)||<0.001|
|1:160||9 (7.7)||5 (3.7)||0.259||Ho||0||10 (7.2)||0.008|
|1:320||15 (12.7)||23 (16.7)||0.477||Centromere||0||11 (7.9)||0.005|
|1:640||21 (17.7)||0||<0.001||NFS||54 (45.8)||58 (42.0)||0.636|
|>=1:1280||21 (17.78)||100 (72.5)||0.002||NDFS||39 (33,0)||0||<0.001|
The ANA HEp-2 assay offered distinctive titer and pattern profiles for ANA-positive individuals and for ARD patients. ANA pattern seemed to be more reliable than ANA titer for discriminating ANA-positive HC and ARD patients. Some ANA patterns (NCS, Ho, Centromere) were exclusively observed in ARD patients while the NDFS pattern was restricted to HC. The NFS pattern was equally frequent in both groups and showed different titer distribution in HC and ARD patients. ANA-positive HC tended to keep ANA reactivity but did not develop evidence of ARD after a 4-year follow-up period.
To cite this abstract, please use the following information:
Mariz, Henrique A., Rodrigues, Silvia H., Campos, Silvia H. B., Ferreira, Gilda A., Sato, Emilia I., Andrade, Luis Eduardo C.; ANA-Positive Healthy Individuals and Autoimmune Rheumatic Patients Present Distinctive Pattern and Titer Profiles at the ANA HEp-2 Assay [abstract]. Arthritis Rheum 2009;60 Suppl 10 :910