Autoantibody (AAb)
Profile, with special reference to ENA, in Indian (Asian) patients
with connective tissue disorders (CTD).
ANURADHA VENUGOPALAN, CHOPRA ARVIND,
STURGESS A, EDMONDS J.
CENTER FOR RHEUMATIC DISEASES, PUNE. THE ST. GEORGE
HOSPITAL, SYDNEY.
In our setting, ENA testing facilities are sparse.
Funded by APLAR Laboratory
Fellowship - 1999
Aim
AAb profile, especially ENA, in patients of CTD.
Methods
81 successive patients of CTD, some under treatment
at a rheumatology referal practice clinic in western
Maharashtra (India), [SLE = 34; PSS = 8; MCTD = 6; Myositis
= 8; unclassifiable CTD (CTD-U) = 25] were selected
and classified as per ACR; primary vasculitis excluded.
ANA (indirect immunofluorescence using HEp 2), dsDNA
(Farr Technique) and ENA (CIEP using guinea pig kidney
and rabbit thymus extract) were tested. If available,
medical records were reviewed for past AAb results.
Results
80% patients were positive for ANA (SLE: 94%; PSS: 100%;
MCTD: 100% Myositis : 86%; CTD-U : 48%). Anti dsDNA
was found in 31% patients (SLE: 65%; PSS: 25%; MCTD:50%;
Myositis:13% CTD-U:12%) Antibodies to ENA was detected
in 56% patients(SLE:74%; PSS:75%; MCTD:100%; Myositis:13%
CTD-U:28%). All ENA seropositives were further characterized.
The results are as follows:
SLE
(N=25)
N (%)
PSS(N=6)
N (%)
MCTD(N=6)
N (%)
CTD-U(N=25)
N (%)
Sm
6 (24)
1(17)
1(17)
3(12)
RNP
5(20)
2(33)
3(50)
3(12)
SS-A
15(60)
1(17)
3(50)
5(20)
SS-B
5(20)
1(17)
2(33)
1(4)
rRNP
4(16)
0(0)
0(0)
1(4)
Scl-70
0(0)
3(50)
0(0)
0(0)
Conclusions
The Indian CTD AAb profile is rather similar to caucasian
data. The lesser frequency of anti dsDNA in SLE (?therapy
effect) needs further probe. ENA Ab may aid diagnosis
in some cases of CTD-U.
CENTER
FOR RHEUMATIC DISEASES (CRD)
Hermes Doctor House, Hermes Elegance,
Convent Street, Camp, Pune – 411 001, Maharashtra, India.
Tel: 020-26348529, 26345624, 26344099
