Juvenile rheumatoid arthritis in affected sibpairs.

OBJECTIVE: To describe the demographics and clinical disease in affected sibpairs (ASPs) with juvenile rheumatoid arthritis (JRA), and to compare JRA as it occurs in ASPs with that from non-ASP JRA populations described in the literature. METHODS: A rare disease research registry was established with a focus on JRA ASPs to facilitate accrual of patients for genetic, epidemiologic, and clinical studies. Physicians likely to care for patients with JRA were made aware of the registry and its goals by a variety of methods and asked to refer patients for entry. RESULTS: To date, 71 ASPs have been registered and complete information has been obtained. These affected sibs differed in age by a mean of 4.1 years (SD 3.4) and in age at disease onset by 2.8 years (SD 3.0). The actual time difference between onset in sib 1 versus sib 2 averaged 4.4 years (SD 4.2). Sixty-three percent of the sibpairs were concordant for sex, and 76% for JRA onset type. Onset type within sibpairs did not appear to be random, based upon comparisons with non-ASP populations. Greater than expected concordance was seen among those with pauciarticular-onset and polyarticular-onset JRA. Seventy-nine percent of the pairs were concordant for course type. Seven sets of twins were included (approximately 10% of the total), all were concordant for onset and course type (6 sets with pauciarticular, 1 set with polyarticular), and disease onset was separated by a mean of only 3.3 months. Within the onset and course types, the clinical disease, such as the female:male ratio, age at onset, and serologic findings, in ASPs resembled that which has been described in the literature. CONCLUSION: A higher than expected degree of concordance for onset type of JRA exists between sibpairs, indicating that genetic influences play a role. Affected sibs do not tend to develop their disease at approximately the same point in time, except for the twin sets. Clinical features of the disease within the various subtypes appear similar to those in non-ASP populations.

Intravenous immunoglobulin in the treatment of polyarticular juvenile rheumatoid arthritis: a phase I/II study. Pediatric Rheumatology Collaborative Study Group.

OBJECTIVE: To obtain preliminary information about the safety and efficacy of intravenous immune globulin (IVIG: Iveegam, Immuno AG, Vienna) in the treatment of polyarticular juvenile rheumatoid arthritis (poly-JRA) resistant to other forms therapy. METHODS: We used a multicentered, phase I/II blinded-withdrawal design with stratified entry. All patients began by receiving open infusions of IVIG at a dose between 1.5 and 2.0 g/kg/infusion (100 g maximum) bimonthly for the first 2 months, then monthly for up to 6 months. Beginning at Month 3, those who met the criteria for "clinically important improvement" were randomized to receive monthly infusions for 4 months of either placebo or IVIG in a double blind (DB) phase. Patients were permitted nonsteroidal antiinflammatory drugs, slow acting antirheumatic drugs, and low dose (< 10 mg/day) prednisone at constant doses. An "early escape" provision in the DB allowed those who showed "clinically important worsening" to again receive IVIG (if taking placebo) or a higher dose of IVIG (if taking the lower dose of IVIG). RESULTS: Efficacy. Twenty-five children entered the trial and 19 (76%) met the criteria for "clinically important improvement" during the open phase (OP) and entered the DB. Three patients completed the OP but failed to meet the criteria for response, and 3 patients dropped out of the OP, none of whom showed benefit from IVIG. Treatment effect sizes produced by IVIG were moderate to large for all variables in the OP. Patients who continued IVIG in the DB continued to show improvement over that achieved in the OP. Those given placebo showed a rapid loss of efficacy, suggesting IVIG has a limited duration of effect after discontinuation. Safety. No patient developed serious or unexpected adverse side effects in the open or DB phases, and none dropped out of the study due to toxicity or side effects. CONCLUSION: Substantial clinical improvement from IVIG is produced in about three-fourths of patients with poly-JRA during open administration, but the duration of the beneficial effect is short after discontinuation. Those with disease < 3 years' duration may be more likely to respond than those who have had their disease for > 5 years. Short term safety is excellent.