The adult patient with polyarticular juvenile idiopathic arthritis

Abstracts

Crianças com a forma poliarticular da artrite idiopática juvenil (AIJ), ao entrarem na idade adulta, têm um quadro similar ao de pacientes com artrite reumatoide (AR) de início no adulto. No presente estudo comparam-se características clínicas e imunológicas desses dois grupos de pacientes. Para isso, foram estudados vinte adultos com AIJ poliarticular e cinquenta pacientes com AR (pareados para sexo e tempo de duração de doença), para presença de autoanticorpos, nódulos subcutâneos, síndrome de Sjögren secundária, hipotireoidismo e para a determinação de índices funcionais e antropométricos. Encontraram-se, nesses dois grupos, características similares, exceto pela presença de fator reumatoide (menor no grupo de AIJ poliarticular; P = 0,026) e menor IMC nos pacientes com AIJ poliarticular (P < 0,001).

artrite reumatoide; artrite idiopática juvenil; fator reumatoide; evolução

BRIEF COMMUNICATION

Department of dermatology, Hospital Universitário Evangélico de Curitiba

Correspondence to

ABSTRACT

When children with polyarticular juvenile idiopathic arthritis (JIA) reach adulthood, they have a condition similar to that of patients with adult onset rheumatoid arthritis (RA). In the present study, the clinical and immunological characteristics of these two groups of patients are compared. The presence of autoantibodies, subcutaneous nodules, secondary Sjögren syndrome, and hypothyroidism, was determined in 20 adult patients with polyarticular JIA and in 50 patients with RA (paired for gender and duration of the disease), as well as the determination of functional and anthropometric indexes. Both groups had similar characteristics, except for the presence of rheumatoid factor (lower in the polyarticular JIA group; P = 0.026) and lower BMI in patients with polyarticular JIA (P < 0.001).

Keywords: juvenile idiopathic arthritis, rheumatoid arthritis, rheumatoid factor, evolution.

INTRODUTION

Childhood idiopathic arthritis or juvenile idiopathic arthritis (JIA) encompasses chronic childhood joint diseases characterized by remissions and exacerbations.¹ Many of these patients will have persistent clinical disease after adolescence, requiring transfer to an adult rheumatologic clinic.²

There are several subtypes of JIA, and this variability is reflected in their clinical, laboratory, and immunogenetic manifestations.¹ Polyarticular JIA (seropositive or seronegative) is the form that most closely resembles adult rheumatoid arthritis (RA).¹ In this form, girls are affected more often, showing involvement of the small joints of the hands and feet, which can lead to swan-neck and boutonnière deformities.¹ When seen in an adult rheumatology clinic, these patients are easily mistaken by patients with RA.

In the present study, anthropometric, clinical, serologic, and functional aspects of adults with polyarticular JIA and RA are compared to determine the similarities and differences between these entities.

After approval by the Ethics on Research Committee, and after all subjects gave their written informed consent, 20 patients with polyarticular JIA and 50 with RA, paired by gender and duration of the disease, were evaluated. This population corresponds to all patients with polyarticular JIA and RA seen in the rheumatology outpatient clinic in 2007; disease duration and length of follow-up were similar in both groups. Eighteen of the 20 patients with polyarticular JIA came from the Pediatric Rheumatology Outpatient Clinic of the same hospital.

Through a questionnaire applied by the same investigator, demographic data, the Steinbrocker functional index,³ and data of the Health Assessment Questionnaire⁴ were collected. The medical records of the patients were reviewed to collect information on autoantibodies profile [antinuclear factor (ANA), rheumatoid factor (RF), anti-Ro/SS-A and anti-La/SS-B], to detect the presence of nodes, association with thyroid dysfunction, secondary Sjörgren syndrome (diagnosed by the American-European Consensus Group on Classification Criteria for Sjögren Syndrome),⁵ and the use of disease-modifying antirheumatic drugs. The autoantibodies mentioned and the thyroid function tests are routinely done in our service, and they were done in all patients who participated in the study.

Comparison among the demographic, clinical, and functional data is summarized below (Table 1).

The therapeutic profile used during the course of the disease by the patients investigated is summarized in Table 2. All patients with JIA and RA used corticosteroids. However, data on the cumulative dose of this medication could not be obtained due to the wide variability of the doses and intermittent use with time.

On Table 2 it is possible to observe that adult patients with polyarticular JIA are shorter, have lower body mass index, and lower incidence of positive RF. Differences were not observed in the other data investigated, namely the presence of nodes, ANA, and associated autoimmune disorders (hypothyroidism and secondary Sjögren syndrome). Interestingly, functional indexes (HAQ and Steinbrocker) were similar in both groups, despite the fact that patients with polyarticular JIA used biological therapy more often, which presupposes a more aggressive treatment. As for presence of the rheumatoid factor and the difference observed in BMI, the more advanced age of the control group could have been a contributing factor.

The literature shows that patients with JIA tend to present a better prognosis than patients with RA, although those studies include the different subtypes of JIA, including oligoarticular types.⁶ In a retrospective study, Wallace et al.⁷ noticed that patients with the oligoarticular types have longer remission periods than those with polyarticular types. In the present study, only the polyarticular types were included. Furthermore, it is possible that pediatric patients with less severe articular disease abandon the follow-up during the transition from the pediatric to the adult rheumatology outpatient clinic, confounding the analysis of this aspect. This period is associated with a high evasion rate from clinical follow-up.² Packham et al.,⁸ studying 256 adult patients with all types of JIA, emphasized the importance of a careful transition from the pediatric to the adult outpatient clinic. Those authors also observed a high level of incapacity and unemployment resulting from persistent disease activity. In this study, 37% of the patients presented Steinbrocker 3 and 4, while 42% had a HAQ > 1.5.

To conclude, it can be said that adult patients with polyarticular JIA differ from patients with RA concerning the weight-height development and the presence of RF. However, the most important finding seems to be that, although patients with polyarticular JIA are much younger than individuals with RA, they show the same degree of incapacity, justifying an even greater vigilance and control of the disease activity.

REFERENCES

• ¹
  Lowell DJ. Juvenile Idiopathic Arthritis. Clinical Features. In Klippel JH, Stone JH, Crofford LJ, White PH (eds.). Primer on Rheumatic diseases. Arthritis Foundation, 13 ed, Springer Sci New York, 2008, pp. 142-53.
• ²
  Tucker LB, Cabral DA. Transition of adolescent patient with rheumatic disease: Issues to consider. Rheum Dis Clin N Am 2007;33:661-72.
• ³
  Klippel J, Dieppe PA. Selected measures for outcome assessment of rheumatic diseases. In Klippel J, Dieppe PA (eds.). Rheumatology. 2 ed, v. 2, London: Mosby, 1998, pp. A1- A11.
• ⁴
  Krishnan E, Sokka T, Hakkinen A, Hubert H, Hannonen P. Normative values for the Health Assessment Questionnaire disability index: benchmarking disability in the general population. Arthritis Rheum 2004;50:953-60.
• ⁵
  Daniels T. Sjögren’s syndrome. In Klippel JH, Stone JH, Crofford LJ, White PH (eds.). Primer on Rheumatic Diseases, 13 ed, New York: Springer, 2008, pp. 389-97.
• ⁶
  Pralahad S, Glass DN. Is juvenile rheumatoid arthritis/juvenile idiopathic arthritis different from rheumatoid arthritis? Arthritis Res 2002;4,S-3:303-10.
• ⁷
  Wallace CA, Huang B, Bandeira M, Ravelli A, Giannini EH. Patterns of Clinical Remission in selected categories of juvenile idiopathic arthritis. Arthritis Rheum 2005;52:3554-62.
• ⁸
  Packham JC, Hall MA. Long term follow up of 246 adults with juvenile idiopathic arthritis: functional status. Rheumatology  2002;41:428-35.

The adult patient with polyarticular juvenile idiopathic arthritis

Liz Wallin; Ana Paula Beckhauser; Francisco Araújo; Osvaldo Haider; Marília B. Silva; Thelma L. Skare

Publication Dates

• Publication in this collection
  03 Aug 2009
• Date of issue
  Aug 2009

History

• Accepted
  16 Mar 2009
• Received
  30 Sept 2008