Juvenile-onset spondyloarthropathies

This article discusses the clinical spectrum and characteristics of juvenile-onset spondyloarthropathies and includes a review of the demographic, clinical, radiographic (and other imaging techniques), and laboratory data of conditions, syndromes, and diseases making up this group. The pathogenic role of several factors in the context of adult-onset patients, but also in regards to studies already performed in juvenile-onset patients, is discussed.

The LMP2 polymorphism is associated with susceptibility to acute anterior uveitis in HLA-B27 positive juvenile and adult Mexican subjects with ankylosing spondylitis

INTRODUCTION

An association between polymorphism of the HLA linked LMP2 locus and the development of acute anterior uveitis (AAU) has previously been described in B27 positive white subjects with ankylosing spondylitis (AS). This study evaluated LMP2 alleles in two HLA-B27 positive Mexican populations of patients with spondyloarthropathy known to have a different clinical spectrum of disease from white people.

PATIENTS AND METHODS

The study populations consisted of 90 AS patients from Guadalajara with predominantly adult onset disease and 80 AS patients from Mexico City with predominantly juvenile onset disease. LMP2-CfoI amplified fragment length polymorphisms were determined after polymerase chain reaction amplification and digestion with CfoI restriction enzyme.

RESULTS

There was an increased LMP2A allelic frequency in patients who had had AAU in both Guadalajara (31.8%) and Mexico City (33.3%) when compared with non-AAU patients (15.2% and 17.7% of Guadalajara and Mexico City populations, respectively). The odds ratio relating LMP2A allelic frequency and AAU for the combined population, stratified by age at onset of disease, was 2.51 (p = 0.01). LMP2 alleles did not influence the age at onset of disease or the development of peripheral arthritis.

CONCLUSIONS

These data support the view that polymorphism at the LMP2 locus is associated with the development of AAU in B27 positive subjects with AS. The requirement for both the less common LMP2 allele and HLA-B27 is consistent with the low prevalence of AAU in Mexican patients with spondyloarthritis.

HLA-DRB1*08 influences the development of disease in Mexican Mestizo with spondyloarthropathy

OBJECTIVE

HLA class II encoded factors may influence the phenotype of ankylosing spondylitis (AS). These include HLA DRB1*07 for peripheral arthritis, and polymorphism of the HLA-linked LMP2 locus and HLA DRB1*08 for acute anterior uveitis (AAU). We studied the relationship between DRB1*08 and disease phenotype in additional populations of individuals with AS.

METHODS

The patient population included 385 unrelated HLA-B27 positive individuals with AS. These included 204 Caucasians and 2 populations of Mexican Mestizo with AS: 106 with predominately adult onset disease from Guadalajara and 75 with predominately juvenile onset disease from Mexico City. The control population of 428 individuals included 210 random and 36 HLA-B27 positive unrelated Canadian Caucasians and 173 random and 9 HLA-B27 positive Mexican Mestizo from Mexico City. DRB1*08 typing was by sequence specific polymerase chain reaction.

RESULTS

A significantly higher prevalence of DRB1*08 was observed in Mexican patients with juvenile onset disease (44.9%) and especially those with undifferentiated spondyloarthropathy (55.6%) compared to normal unrelated Mexican Mestizo (25.4%) (p < 0.01 for both) and in patients with undifferentiated spondyloarthropathy versus B27 controls (11.1%) (p = 0.03), although no significant differences were observed in within patient group comparisons based on phenotypic features of disease such as AAU and age at onset. No significant relationship between DRB1*08 and disease phenotype was evident in Caucasian individuals.

CONCLUSION

Our data suggest DRB1*08 may influence the phenotype of spondyloarthritis in Mexican Mestizo, but do not support the view that DRB1*08 influences the development of AAU, as reported in a Japanese population.

Efficacy and safety of meloxicam in patients with rheumatoid arthritis

OBJECTIVE

To evaluate the efficacy and safety of meloxicam, a new acidic enolic nonsteroidal anti-inflammatory drug, at doses of 7.5 and 15 mg once daily in patients with rheumatoid arthritis (RA).

METHODS

Meloxicam 15 and 7.5 mg daily was administered for 21 days in this double blind, randomized, placebo controlled study. 159 patients received meloxicam 7.5 mg, 162 received meloxicam 15 mg, and 147 received placebo.

RESULTS

Meloxicam 15 mg once daily was significantly superior (p < 0.05) to placebo in 3 of the 4 primary endpoints (disease activity assessed by the investigator, disease activity assessed by the patient, and reduction of the number of tender/painful joints). No difference was observed regarding number of swollen joints. The difference between meloxicam 7.5 mg once daily and placebo reached statistical significance in 2 of the 4 primary endpoints, disease activity assessed by the patient and number of tender/painful joints. A statistically significant difference between meloxicam 1.5 mg and 7.5 mg was not observed for any primary endpoint. The rating of global tolerance by investigators and patients at the end of the study was similar in the 3 treatment groups, indicating that meloxicam and placebo were generally similarly well tolerated. However, there was a slightly higher incidence of gastrointestinal (GI) disturbances reported by patients receiving meloxicam 15 mg. GI adverse events were reported by 11, 11, and 16% of patients in the placebo, meloxicam 7.5 mg, and meloxicam 15 mg groups, respectively. None were serious.

CONCLUSION

Meloxicam in daily doses of 7.5 and 15 mg is effective in treating the signs and symptoms of RA.

Genuine ankylosing spondylitis in children: a case-control study of patients with early definite disease according to adult onset criteria

OBJECTIVE

To describe a group of children with spinal and sacroiliac (SI) joint involvement since the initial year of disease, who fulfilled current adult onset ankylosing spondylitis (AS) diagnostic criteria within 3 years of onset.

METHODS

We conducted a case-control study of 44 patients with juvenile onset definite AS. 14 cases (Group A) and 30 controls (Group B) were studied; groups were matched by age at onset (age < or = 16 years), duration of disease at the time of admission to our clinic (< or = 1 year), diagnostic criteria (New York criteria), and period of observation. We compare demographic characteristics, as well as peripheral joint disease 6 and 12 months after onset, and analyze Group A at time of diagnosis. In contrast to Group A, patients in Group B had a syndrome of peripheral arthritis and enthesitis (SEA syndrome), but no axial symptoms or definite diagnosis of AS in the first 5 years of disease.

RESULTS

Patients in Group A were HLA-B27 positive boys with peripheral arthritis and enthesitis who differed from those in Group B in the frequency of pauciarthritis and polyarthritis at one year of disease (0 vs 36.7% and 100.0 vs 63.3%; p = 0.008) and age at diagnosis (9.03 +/- 1.13 vs 16.5 +/- 3.3 years; p > 0.0001). Six patients in Group A had lumbar pain and 3 SI joint pain 6 months after onset; at the end of the first year, the number increased to 10 and 6 patients, respectively. At time of diagnosis (2.36 +/- 0.72 yrs after onset), all patients in Group A had radiographic sacroiliitis and spinal, SI, and/or costosternal pain, 11 reduced anterior spinal flexion, and 6 reduced chest expansion.

CONCLUSION

There is a less common subgroup of adult-like juvenile onset AS who develop clinical and radiographic evidence of disease affecting the axial skeleton earlier than children progressing from SEA syndrome to AS 5 to 10 years after onset.

Antibody response to nitrogenase-positive and -negative Klebsiella pneumoniae strains in juvenile-onset ankylosing spondylitis patients and their first degree relatives: lack of differential recognition of the bacterial nitrogenase

In the search for the pathogenic consequences of the molecular mimicry between the Klebsiella pneumoniae nitrogenase and the HLA-B27 antigen, sera from individuals belonging to 16 kindreds with juvenile-onset ankylosing spondylitis cases, were analyzed for antibodies against nitrogenase-positive and -negative K. pneumoniae whole bacterial extracts. An initial screening for nitrogenase producing K. pneumoniae strains was performed in 31 clinical isolates. The best nitrogenase producing strain was selected as well as a non producing one for immunoblot analysis using sera from 82 subjects, 55 HLA-B27 positive, of which 26 had some clinical manifestations. Even though electrophoretic patterns were different in both strains, there was no distinctive differential recognition of the 30-40 kDa proteins where the nitrogenase subcomponent which shares the sequence QTDRED with the HLA-B27 molecule is located. On the other hand, strong recognition of a protein of 60 kDa (p60Kp) was detected in 75% of HLA-B27 positive tested subjects independently of their clinical status. Studies on the nature of this protein and its participation in the pathogenesis of ankylosing spondylitis are now in progress.

Reliability of the articular examination in children with juvenile rheumatoid arthritis: interobserver agreement and sources of disagreement

OBJECTIVE

To assess the interobserver agreement of articular examination in children with juvenile rheumatoid arthritis (JRA) and identify sources of disagreement.

METHODS

Four rheumatologists graded tenderness/pain on motion, swelling, and limitation of motion in the joints of 10 children with JRA, as recommended by the Pediatric Rheumatology Collaborative Study Group, and 17 different joint indices were computed. Agreement was measured by kappa (kappa) and intraclass correlation coefficients (Ri).

RESULTS

All 4 observers detected tenderness in 15.7% of the joints, but they disagreed (2 vs 2) on 4.2% (kappa = 0.71). They detected swelling in 5.2% but disagreed on 6.2% (kappa = 0.47). They found limitation in 4.9%, but disagreed on 8.1% (kappa = 0.54). The tender joint count, and the American Rheumatism Association cooperating clinics and Hart modified Ritchie indices were the most reliable (Ri > 0.93); the swelling severity index fared the worst (Ri = 0.40). There were differences in examination maneuvers and judgment among examiners. Discrepancies were larger in metacarpophalangeal joints and in patients with many involved joints.

CONCLUSION

There was low agreement in the assessment of joint swelling and limitation of motion. Differences in examiners' techniques, patients with severe disease, and the small hand joints were important sources of disagreement.

Characterization of B27 haplotypes by oligotyping and genomic sequencing in the Mexican Mestizo population with ankylosing spondylitis: juvenile and adult onset

The aim of this study was to investigate the contribution of the different B27 subtypes in the Mexican Mestizo population with juvenile and adult AS. No differences in the distribution of B27 subtypes were found between both populations, B*2705 being the predominant subtype followed by B*2702. Transracial gene mapping was performed in order to find out the origin of the B27 alleles of the Mexican Mestizos. A PCR with SSOPs was used to analyze the polymorphism in exons 2 and 3 of HLA-B27 and HLA-C related alleles. This population shares with the Spanish Caucasians B*2705 and B*2702, which are absent in Central and South American Indians. AS and healthy Mexican mestizo donors were analyzed to ascertain B27/Cw haplotypes. The B27/Cw linkage arrangements seen in mestizos are similar to those reported for Caucasian Spaniards with three different haplotypes positively associated with AS in both populations, B*2705/Cw*0102, B*2705/Cw*02022, and B*2702/Cw*02022, suggesting that B27 in Mexicans may be due to a recent Caucasoid admixture with the Spanish genes. Finally, a strategy for sequence analysis of exons 2 and 3 from genomic DNA of HLA-B27 alleles was developed. A novel HLA-B27-like allele typed serologically as B27 was identified and sequenced by this method in a healthy Mexican mestizo, corresponding to the B*7301 variant found with low frequency in different populations. Analysis of the association of B*7301 to AS would require an extensive study in different populations and could provide insights into the molecular structure of the alleles involved in the disease.

The early clinical recognition of juvenile-onset ankylosing spondylitis and its differentiation from juvenile rheumatoid arthritis

OBJECTIVE

To determine which early clinical data differentiate juvenile-onset ankylosing spondylitis (AS) from juvenile rheumatoid arthritis (JRA).

METHODS

Medical records of 35 patients with juvenile-onset AS and 75 with JRA (excluding type II pauciarticular JRA), all of whom had disease onset at age < or = 16 years, disease duration of < or = 2 1/2 years at the initial visit to the rheumatology clinic, and followup of > or = 10 years, were analyzed retrospectively with regard to features of disease found 6 months, 12 months, and 10 years after onset.

RESULTS

At 6 months, various features appeared more frequently in the juvenile-onset AS group than in the JRA group, i.e., pauciarthritis (54.3% versus 30.7%; P = 0.03, odds ratio [OR] = 2.7), enthesopathy (82.9% versus 0%; P < 0.0001, OR = 321.4), tarsal disease (71.4% versus 1.3%; P < 0.0001, OR = 185.0), and lumbar/sacroiliac symptoms (11.4% versus 0%; P = 0.02, OR = 11.9). At 12 months, the features found more frequently among juvenile-onset AS patients than JRA patients were enthesopathy (88.6% versus 4.0%; P < 0.0001, OR = 186.0), tarsal disease (85.7% versus 10.7%; P < 0.0001, OR = 50.3), and knee disease (100.0% versus 82.7%; P = 0.04, OR = 8.0). Involvement of the upper extremities (especially the hands) was found in significantly fewer juvenile-onset AS patients compared with the JRA group. Definite involvement of the spine and sacroiliitis in juvenile-onset AS occurred after a mean +/- SD of 7.3 +/- 2.0 years.

CONCLUSION

Regardless of axial disease, enthesopathy and tarsal disease in children who have arthritis of the lower, but not of the upper extremities differentiate juvenile-onset AS from JRA within 1 year of symptoms. The discriminative value of these parameters approaches that of axial disease (the gold standard) throughout the followup period.

Chest expansion in healthy adolescents and patients with the seronegative enthesopathy and arthropathy syndrome or juvenile ankylosing spondylitis

OBJECTIVE

To determine chest expansion measurements in healthy children and those with juvenile spondyloarthropathies.

METHODS

Chest expansion, as defined by the difference between maximal inspiration and maximal expiration was measured in 157 healthy adolescents (112 boys and 45 girls) aged 11 to 15 years, 20 patients with the seronegative enthesopathy and arthropathy (SEA) syndrome and 15 with juvenile ankylosing spondylitis (AS).

RESULTS

The median and mean chest expansion (+/- 2 SD) were 5.0 cm and 5.6 cm (+/- 3.52) for the whole group of healthy adolescents, 6.0 cm and 5.9 cm (+/- 3.64) for boys and 5.0 cm and 4.8 cm (+/- 2.69) for girls. The frequency distribution of the values was leptokurtic and skewed to the right and did not follow the normal pattern; nearly 90% of the measurements fell within the interval from 3 to 9 cm. Of all variables analyzed (age, height, weight, sex and health/disease status), only height correlated with chest expansion (r = 0.20, p = 0.01). Even so, the effect of all these variables explained only 13% of the total variance of the measurements. Interobserver and intraobserver intraclass correlation coefficients were moderate (0.58 and 0.67, respectively). Mean values and cumulative frequency distribution in asymptomatic and symptomatic SEA syndrome and patients with juvenile AS were similar to those from healthy adolescents.

CONCLUSION

Measuring chest expansion does not seem to be a useful method for the rare cases of early involvement of the chest joints in SEA syndrome and juvenile AS.

Spondyloarthropathies and psoriatic arthritis in children

Data that are relevant to the general understanding of the juvenile-onset spondyloarthropathies are reviewed here. Seronegative enthesopathy and arthropathy syndrome is considered the earliest recognizable form of juvenile-onset spondyloarthropathy, from which other syndromes and diseases emerge. The group also includes juvenile-onset ankylosing spondylitis, a disease defined in adult-based terms when definite changes have occurred in the axial joints; ankylosing tarsitis, a complex disorder in which foot problems resemble those of the spine in ankylosing spondylitis; Crohn's disease and ulcerative colitis-related peripheral and, especially, HLA-B27 axial disease; reactive arthritis and Reiter's syndrome, which might be further classified according to its cause; and juvenile psoriatic arthritis, a disease that resembles juvenile rheumatoid arthritis more than does juvenile-onset spondyloarthropathy.

Juvenile ankylosing spondylitis

We are beginning to understand the clinical nature of JAS, its relationship with other SSA, and factors involved in its pathogenesis. Clinical data may now allow early recognition of JAS through the identification of children with the SEA syndrome or chronic arthritis associated with the HLA-B27. Comparative clinical studies of the prevalence of the disease and the role of immunogenetic, racial and environmental factors are needed. It may be necessary to review current criteria for the diagnosis of JRA and to develop similar criteria for the diagnosis of AS in childhood and adolescence.

New clinical and radiographic features of the seronegative spondyloarthropathies

This article reviews new data supporting the hypothesis that the clinical spectrum of the seronegative spondyloarthropathies is wider than previously realized. It describes the literature in general and specific reports on the prevalence and clinical features of seronegative spondyloarthropathies in a number of different populations from America and Asia. Undifferentiated or unclassified spondyloarthropathies are now recognized more frequently. There is an extensive analysis of new proposals for nomenclature and criteria for classification that need to be validated. The normal appearance and biomechanics of the sacroiliac joints as well as new imaging techniques to approach them in several diseases are also discussed. Clinical, radiographic, and histopathologic findings in spinal disease and further observations on gut inflammation and intestinal permeability are also presented here. A long list of clinical associations of the seronegative spondyloarthropathies is also given.

Ankylosing spondylitis in the Mexican mestizo: patterns of disease according to age at onset

We studied 87 Mexican mestizo patients (82 men and 5 women) with definite ankylosing spondylitis (AS) with particular reference to juvenile and adult onset types. HLA-B27 was present in 32 of 38. Forty-seven patients (54.0%) had onset before the age of 16 years and 40 (46.0%) thereafter. By the end of the 1st year of disease, main features included spinal involvement in 44 (50.6%), peripheral arthropathy in 57 (65.5%) and enthesopathy in 41 (47.1%). Frequency of these increased up to 100.0, 79.3 and 64.4%, respectively, through the course of the disease. Peripheral arthritis and/or enthesopathy occurred in 89.4 and 63.1% of juveniles and 37.5 and 27.5% of adults, respectively, while lumbar pain and/or stiffness occurred in 23.4% of the former and 82.5% of the latter during the first year of disease. Additional findings were high erythrocyte sedimentation rate, anemia and hypergammaglobulinemia. Uveitis was the commonest extraarticular manifestation occurring in 20.6%. Our data suggest that the clinical pattern of AS in our patients was influenced by both age at onset and sex distribution of the disease.

Axial involvement in the seronegative enthesopathy and arthropathy syndrome and its progression to ankylosing spondylitis

We studied prospectively the clinical and radiographic features of sacroiliac and spinal involvement in 20 patients with seronegative enthesopathy and arthropathy. This group was compared with 25 patients with a polyarticular onset form of juvenile rheumatoid arthritis (JRA) and 28 with definite ankylosing spondylitis (AS) of juvenile onset. A significant increasing proportion of patients with seronegative enthesopathy and arthropathy developed back complaints and radiographic sacroiliitis fulfilling the diagnostic criteria for AS from the 3rd-5th year of disease (47.1-75.0%) and thereafter (92.3%). Back complaints were rarely seen in JRA and, furthermore, sacroiliitis of the AS type nerve occurring in this group. There were no significant differences between the group with seronegative enthesopathy and arthropathy and juvenile AS, either at onset or through the years. Clinical and radiographic assessment of axial involvement in children at risk should include a careful analysis of symptoms, periodical measurements of the spinal flexion and, starting from the 3rd year, radiographs of the pelvis.

Immunoregulatory defects in juvenile rheumatoid arthritis. Comparison between patients with the systemic or polyarticular forms

Studies of cellular immunity in juvenile chronic arthritis (juvenile rheumatoid arthritis, JRA) have been scant, controversial, or have not addressed the issue of the different forms of the disease. We studied 23 patients with JRA of either systemic (n = 8) or polyarticular (n = 15) type of onset and compared the findings to those made in 10 healthy children of similar age. Both groups of patients with JRA were found to have increased CD8 T cells, normal production of interleukin-1 and 2 and decreased production of B cell stimulatory factor in their peripheral blood. In addition, patients with systemic JRA were found to have decreased spontaneously expanded and concanavalin-A induced suppressor functions. These findings in both forms of JRA are distinguishable from those that have been made in other connective tissue diseases including the adult form of rheumatoid arthritis.

Clinical experiences with the intramuscular injection of tiaprofenic acid in rheumatic diseases, with particular emphasis on time of onset and duration of the analgesic effect

The efficacy of intramuscular tiaprofenic acid (TA) was investigated in 3 separate studies: a multicentre open study involving 487 patients with various rheumatic conditions: an open study of 31 patients with active osteoarthritis of the knee; and an open comparative study with ketoprofen involving 30 patients with acute gout. In each of the studies tiaprofenic acid was given at a dose of 200mg intramuscularly twice daily for 5 days. In addition to clinical efficacy and tolerance, the time of onset and duration of the analgesic effect were also assessed. Significant improvements in both pain intensity and inflammation were seen in 60 to 70% of all patients in the 3 studies (p less than 0.0001). Benefits from tiaprofenic acid injection were noted within 60 minutes by about 47% of the patients with acute gout and about 85% of the whole group of patients enrolled in the multicentre study. The analgesic effect lasted from 8 to 12 hours in about 52% of the latter patients, and the overall effect was assessed as either good, very good or excellent in 62.5 to 100% of patients. Results from the comparative study with ketoprofen in acute gout patients showed a better and faster beneficial effect in the group receiving tiaprofenic acid. Thus the intramuscular administration of tiaprofenic acid at a dose of 200mg twice daily for 5 days to 533 patients with different rheumatic conditions resulted in good analgesic and anti-inflammatory activities with a rapid and sustained effect, and was also well tolerated.

Antibodies to peptidoglycan in juvenile onset ankylosing spondylitis and pauciarticular onset juvenile arthritis associated with chronic iridocyclitis

Using an indirect enzyme linked immunosorbent assay, antibodies of the IgG class to Streptococcus pyogenes group A peptidoglycan-polysaccharide polymers (PG-GSP) were measured in the sera of 37 patients with juvenile onset ankylosing spondylitis (JAS), 22 with pauciarticular onset juvenile arthritis associated with chronic iridocyclitis and 20 healthy children. Mean antibody activity, measured in arbitrary units, was of 184 U in JAS and 250 U in chronic iridocyclitis (p = NS). The results in both groups differed significantly from those found in healthy children (p less than 0.001 and p less than 0.01, respectively). This suggests either a possible role of bacterial cell wall products in the pathogenesis of these disorders or a state of immune reactivity to PG-GSP in these children.

Anterior spinal flexion in healthy Mexican children

We investigated anterior spinal flexion (ASF) in a group of 250 healthy Mexican children (125 boys and 125 girls) aged from 6 to 15 years using the Schober's and Macrae and Wright's techniques and 4 new variants. Two of these variants were the more reliable methods of measuring the ASF in children. Marks either 5 cm (Method 3) or 10 cm (Method 4) above and 2.5 cm below the lumbosacral junction were made in the midline of the back with the children standing upright. After bending their trunks, the distraction between the inferior and superior marks was measured. ASF did not increase nor decrease with age. Highest values were found in boys. Values of at least 4 and 6 cm for boys and 3 and 5 cm for girls using Methods 3 and 4 are required to consider ASF in children aged from 6 to 15 as normal.