Background & objectives: Early onset pauciarticular disease with uveitis is distinctly uncommon in Indian children with juvenile rheumatoid arthritis (JRA). The occurrence of anti-histonc antibodies (AHA) in serum is strongly associated with presence of uveitis. There is a paucity of information from India on the levels of AHA in patients of JRA. In this study, an attempt was made to evaluate the levels of IgG and IgM antibodies to histones in children with JRA in north India.
Methods: Scrum samples of 148 children with JRA (84 boys, 64 girls) were collected. Clinical details including onset, symptoms and course of the disease in each patient were recorded. Detailed eye examination including slit lamp examination was done in all patients at presentation and yearly thereafter to rule out uveitis. The presence of antihistone IgG and IgM antibodies was studied by ELISA. Antinuclear antibodies (ANA) were measured by indirect immunofluorescence using HEP-2 cells as substrate at a screening dilution of 1:40.
Results: Of the 148 children, 54 had pauciarticular (12 early onset and 42 late onset), 64 polyarticular and 30 systemic onset disease respectively. ANA were present in two children. AHA were raised in 15 (10%) children, of whom 10 had IgM antibodies, 3 had IgG and 2 had both isotypes. None of the children with early onset pauciarticular disease had uveitis, ANA or AHA.
Interpretation & conclusion: The low occurrence of AHA and uveitis in our subset of patients with JRA is in contrast to that reported from Western countries. The low occurrence is unlikely due to technical reasons as the antigen that has been used consistently showed significant binding to serum from patients with systemic lupus erythematosus (SLE). This is in accordance with the rarity of early onset pauciarticular disease and chronic uveitis in these patients. More studies from other parts of the country are required to validate this observation.
Key words Antihistone antibodies - antinuclear antibodies - autoantibodies -juvenile idiopathic arthritis - uveitis
Juvenile rheumatoid arthritis (JRA) from the Indian subcontinent is different from that seen elsewhere, particularly in the West. The subset of children with early onset pauciarticular disease with uveitis is distinctly uncommon1-3. The presence of antinuclear antibodies (ANA) in children with JRA is strongly associated with the development of chronic uveitis4. More specifically, uveitis is associated with autoantibodies to histories5,6. Interestingly, there appears to be no correlation between the detection of antihistone antibodies (AHA) as detected by ELISA or immunoblotting and antinuclear antibodies detected by immunofluorescence in JRA5, unlike that seen in serum of SLE patients.
There are no systematic studies from India which have tried to analyze why early onset pauciarticular disease with uveitis is rare in India and whether this could be due to serological differences as compared to patients from the western countries. Also, there is paucity of data from India regarding the occurrence of antihistone antibodies in patients with JRA and its relationship to the occurrence of uveitis. Therefore, in this hospital based prospective study, the presence of AHA in north Indian children with JRA was studied to see if there is any underlying serological difference that could explain paucity of uveitis in our population with JRA.
Material & Methods
Patients: A total of 148 children satisfying American Rheumatology Association (ARA) criteria7 for the diagnosis of JRA attending the Immunology Clinic from 1991 to 2001 at the Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGIMS), Lucknow, Uttar Pradesh were included. Clinical details including onset, symptoms and course of the disease in each patient were recorded. Detailed eye examination including slit lamp examination was done in all patients at presentation and yearly thereafter to rule out uveitis. Serum samples were collected at presentation. Some of the patients were in the category of adults at the time of presentation but the onset of disease was in their childhood satisfying the criteria for JRA. The scrum samples were stored at - 80°C. The controls (n= 84) included 25 children and 59 healthy blood donors. The study was approved by the institutional ethics committee.
The minimum sample size was calculated based on a pre test probability of AHA positivity in patients of 0.5 and in controls of 0.05. The power of the study was kept at 99 per cent with alpha error at 0.01 using Epi Info software. With this the minimum number required was 39 in each group. We included more than double the number of controls and all samples available from patients with JRA.
Antinuclear antibody (ANA): ANA was detected by the indirect immunofluorescence using Hep-2 cells as substrate at a screening dilution of 1:40(8).
Enzyme linked immunosorbent assay (ELISA) for anti-histone antibodies: AHA were detected using Monestier's method9 with certain modifications. The modification was the use of calf thymus histone (Sigma, USA) as antigen at 10 pg/ml concentration.
A standard curve was plotted using doubling dilution of a serum sample selected from a panel of serum samples from patients with SLE, because of reproducible binding by the above assay. Doubling dilutions of the serum samples were used from 1:500 to 1:64,000 in each plate. The lower plateau was arbitrarily assigned 1 arbitrary unit (AU). The results are expressed in AU. A sample was cosidered positive when the value was more than 2 standard deviation above the mean in the control group. The average intra- and interplate variations were less than 10 per cent based on 12 assays.
The proportions of patients and controls with antibodies were compared by the Fisher's exact test.
Results & Discussion
The study population included 148 north Indian patients (84 boys and 64 girls) with JRA, 54 (36.5%) having pauciarticular, 64 (43.2%) polyarticular and 30 (20.3%) with systemic onset disease. The median age of patients at presentation was 14 yr (range, 2-26 yr) and the median age at onset of disease was 9.5 yr (range, 1.5-14 yr). The median age of control children was 9 yr with a range of 3-12 yr, while the median age of control adults was 25 yr with a range of 18-35 yr. Five patients (all male) had uveitis and had late onset pauciarticular disease. There were 12 children (10 boys, 2 girls) with pauciarticular disease below 6 yr but none of them had uveitis at presentation or on follow up.
Only two patients (1.4%) had antinuclear antibodies and both had late onset seropositive polyarticular disease. IgA anti histone antibodies were elevated in 5 (3.4%) patients with JRA whereas among the controls, only two had mildly elevated values. The cut-off value was 3.95 AU/ml (mean ± 2SD, 2.3 8± 1.57). IgG AHA were elevated in 12 patients as compared to one in the control subject (P
The major observation of this study is low occurrence of uveitis, antinuclear and anti-histone antibodies in north Indian patients with JRA. Recurrent anterior uveitis was seen in only 5 patients with JRA, all of whom had late onset pauciarticular disease. The risk of uveitis for antinuclear antibody positive females with age of onset of pauciarticular JRA
The ANA positivity rate was very low in our study. Only two children with seropositive polyarticular onset JRA had antinuclear antibodies. They did not develop uveitis on regular follow up including slit lamp examination. In contrast, in the West, ANAs are present in 20 to 45 percent of the patients with JRA4,14. The ANA positivity in serum using HEP-2 cells in SLE patients was found to be 99 per cent (data not shown). It is unlikely that the low positivity in patients with JRA in the present study is due to technical reasons. An Indian study from Madras15 has shown a high ANA positivity (35%) in patients of JRA, while studies3,11 from north India showed a low ANA positivity of 1.3 and 4.5 per cent respectively.
Further, using sensitive ELISA, AHAs were found to be present in only about 10 per cent (15/148) of our patients. Antibodies against histone have been found in about 50 per cent of patients with JRA16-18 and up to 75 per cent of patients with pauciarticular JRA6,9. Job-Deslandre et al19 detected antibodies to histones in 59 per cent of children with JRA, mainly in the pauciarticular onset group. Monestier et al9, using histone ELISA against H1, H2A, H2B, H3 and H4 showed elevated IgM anti-histone antibodies in pauciarticular JRA with uveitis. The two children, who were positive for ANA in the present study, did not have AHA. The occurrence of anti-histone antibodies in our patients with JRA is much lower than that reported in literature from the West. This low occurrence is unlikely due to technical reasons as the antigen used consistently showed significant binding to sera from patients with SLE.
Our findings suggest that there is a paucity of anti-histone and antinuclear antibodies in our cohort of children with JRA, which is in accordance with the rarity of early onset pauciarticular disease and chronic uveitis in these patients. More studies from other parts of the country are required to validate this observation.
Acknowledgment
The authors thank Shri Sanjay Dwivedi for technical assistance. The last author thanks Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow for financial support provided as an intramural grant.
References
1. Aggarwal A, Misra R. Juvenile chronic arthritis in India: is it different from that seen in Western countries? Rheumatol Int 1994; 14 : 53-6.
2. Aggarwal A, Misra RN. Juvenile rheumatoid arthritis in India - rarity of antinuclear antibody and uveitis. Indian J Pediatr 1996; 63 : 301-4.
3. Singh S, Salaria M, Kumar L, Minx R, Datta U. Sehgal S. Clinico-immunological profile of juvenile rheumatoid arthritis at Chandigarh. Indian Pediatr 1999; 36 : 449-54.
4. Kotaniemi K, Kautiainen H, Karma A, Aho K. Occurrence of uveitis in recently diagnosed juvenile chronic arthritis: a prospective study. Ophthalmology 2001; 108 : 2071-5.
5. Southwood TR, Malleson PN. Antinuclear antibodies and juvenile chronic arthritis (JCA): search for a specific autoantibody associated with JCA. Ann Rheum Dis 1991; 50 : 595-8.
6. Leak AM, Tuuillon N, Muller S, Woo R Study of antibodies to histones and histone synthetic peptides in pauciarticular juvenile chronic arthritis. Br J Rheumatol 1993; 32 : 426-31.
7. Brewer EJ Jr, Bass J, Baum J, Cassidy JT, Fink C, Jacobs J, et al. Current proposed revision of JRA criteria. JRA Criteria Subcommittee of the Diagnostic and Therapeutic Criteria Committee of the American Rheumatism section of The Arthritis Foundation. Arthritis Rheum 1977; 20 (2 Suppl.) : 195-9.
8. Humbel RL. Detection of antinuclear antibodies by immunofluorescence. In : van Venrooji WJ, Maini RN, editors. Manual of biological markers of disease, Section A2. Dordrecht Kluwer: 1993 p. 1-16.
9. Monestier M, Losman JA, Fasy TM, Debbas MH, Massa M, Albani S, et al. Antihistone antibodies in antinuclear antibody-positive juvenile arthritis. Arthritis Rheum 1990; 33 : 1836-41.
10. Chylack LT Jr, Dueker DK, Pihlaja DJ. Ocular manifestations of juvenile rheumatoid arthritis : pathology, fluoresceiniris angiography and patient care patterns. In : Miller JJ III, editor. Juvenile rheumatoid arthritis. Littleton: PSG Publishing Company 1979; p. 149-63.
11. Seth V, Kabra SK, Semwal OP, Jain Y. Clinico-immunological profile in juvenile rheumatoid arthritis- an Indian experience. Indian J Pediatr 1996; 63 : 293-300.
12. Arguedas O. Fasth A, Andersson-Gare B. Porras O. Juvenile chronic arthritis in urban Sas Jose, Costa Rica: a 2 year prospective study. J Rheumatol 1998; 25 : 1844-50.
13. Fujikawa S. Okuni M. Clinical analysis of 570 cases with juvenile rheumatoid arthritis: results of a nationwide retrospective survey in Japan. Acta Paediatr Jpn 1997; 39 : 245-9.
14. Lang BA. Shore A. A review of current concepts on the pathogenesis of juvenile rheumatoid arthritis. J Rheumatol (Suppl.) 1990; 21 : 1-15.
15. Chandrasekaran AN, Rajendran CP, Madhavan R. Juvenile rheumatoid arthritis-Madras experience. Indian J Pediatr 1996; 63 : 501-10.
16. Ostensen M, Fredriksen K, Kass E, Rekvig OP. Identification of anti-histone antibodies in subsets of juvenile chronic arthritis. Ann Rheum Dis 1989; 48: 114-7.
17. Malleson P, Petty RE, Fung M, Candido EP. Reactivity of antinuclear antibodies with histones and other antigens in juvenile rheumatoid arthritis. Arthritis Rheum 1989; 32 : 919-23.
18. Pauls JD, Silverman E, Laxer RM, Fritzler MJ. Antibodies to histones H1 and H5 in sera of patients with juvenile rheumatoid arthritis. Arthritis Rheum 1989; 32 : 877-83.
19. Job-Deslandre C, Kapel N, Weill BJ, Maheu E, Menkes CJ. Study of antinuclear and anti-histone antibodies in chronic juvenile arthritis. Rev Rhum Mal Oste Oartic 1989; 56 : 31-3.
A. Wakhlu, D. Gupta, Amita Aggarwal & R. Misra
Department of Immunology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
Received March 13, 2003
Reprint requests: Dr Ramnath Misra, Department of Immunology, Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow 226014, India
e-mail: mmisra@sgpgi.ac.in
Copyright Indian Council of Medical Research Nov 2003
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