Elevated serum transferrin receptor concentration in children with juvenile chronic arthritis as evidence of iron deficiency.

OBJECTIVES: Active juvenile chronic arthritis (JCA) is accompanied by anaemia of chronic disease, which may be indistinguishable from anaemia due to iron deficiency. We speculate that elevation of the serum transferrin receptor (sTfR) concentration, which should not be influenced by inflammation, would be useful for detecting the role of iron status in anaemic children with JCA. METHODS: sTfR concentrations were measured in 30 children with JCA. RESULTS: The median sTfR was elevated, 6.1 (range 3.4-13.0) mg/l. In 13 patients (43%) the concentrations exceeded the upper limit for healthy subjects. Haemoglobin (r = - 0.48, P = 0.008), mean corpuscular volume (r = - 0.47, P = 0.009) and mean corpuscular haemoglobin (r = - 0.65, P = 0.0001) correlated inversely with sTfR concentration. CONCLUSIONS: In 13 of the 30 patients with JCA, the sTfR concentration, which is an indicator of iron status and erythropoiesis, was elevated. The results raise the possibility that sTfR is able to distinguish iron-deficiency anaemia from anaemia of chronic disease. It should be further explored as a candidate.

Mandibular condyle lesions related to age at onset and subtypes of juvenile rheumatoid arthritis in 15-year-old children.

The severity of lesions in the temporomandibular joint (TMJ) area and their association with age at onset, the various forms of juvenile rheumatoid arthritis (JRA), and certain serologic tests for rheumatoid factor (RF), antinuclear antibodies (ANA), and human leukocyte antigen (HLA)-B27 were determined in 15-yr-old children. The series comprised 121 JRA children, 78 girls and 43 boys, in whom an analysis had recently been made of the relation of TMJ lesions to jaw movement and occlusal status. The mean age at onset was 7.3 yr, the girls contracting JRA earlier than the boys. Also, the girls with lesions in the TMJ area were significantly younger than those with no lesions. TMJ abnormalities were found in 50% of cases with a pauciarticular or systemic onset, but in 72% of those representing the polyarticular subtype. Flattened condyles and grave lesions were equally represented in all subgroups and in both sexes. A crossover from onset type to present diagnosis was found in 30% of the cases, mostly from pauciarticular to polyarthritis, which also increased the risk of TMJ lesions from 50 to 60%. RF, ANA, or HLA-B27 alone did not seem to be associated with a risk of TMJ abnormalities. Maximal opening capacity is more restricted in patients with early onset or a polyarticular mode of JRA. Since the TMJ is affected in more than half of JRA children, regular measurements of maximal movements of the mandible or roentgenologic examinations of the TMJ are essential for their optimal treatment.

Treatment of juvenile rheumatoid arthritis with diclofenac sodium.

Diclofenac sodium was investigated in the treatment of juvenile rheumatoid arthritis (JRA). The pharmacokinetics of diclofenac in children aged 2-7 was assessed. Seven patients were included in a single-dose trial to determine plasma levels and renal elimination of diclofenac sodium. Venous blood samples were taken at 0, 0.5, 1, 2, 4 and 6 hours after administration of a 25 mg enteric-coated Voltaren tablet. Urine was collected before and 0-6 and 6-12 hours after tablet ingestion. Maximum concentrations ranged from 0.79 to 4.25 micrograms/ml, and were found between 0.5 and 2 hours. Renal elimination of total diclofenac ranged from 5.4 to 10.2% of the oral dose in 6 of the 7 patients. The youngest patient (2 years) had a lower elimination rate (2.25%) during the 12 hours observed. The values for children over 2 years corresponded to the range measured in adults. The pharmacokinetic study was followed by a placebo-controlled study with diclofenac sodium and acetylsalicylic acid (ASA) for 2 weeks in 45 hospitalized patients aged 3-15 years. The patients were randomly assigned to either: DS 2-3 mg/kg/day, microcrystallized ASA 50-100 mg/kg/day, or placebo matching diclofenac. Global evaluation of therapeutic efficacy showed improvement in 73% of the patients in the diclofenac group, in 50% of the ASA group and in 27% of the placebo group. A statistically significant difference between these groups was found (p less than 0.05). The sum of grades of joint tenderness decreased during the 2 weeks in 67% of patients in the diclofenac group, in 56% of the ASA group and in 36% of the placebo group.(ABSTRACT TRUNCATED AT 250 WORDS)

Ibuprofen levels in serum and synovial fluid.

Ibuprofen levels were measured in the serum and synovial fluid of 33 children (mean age 11 years) with juvenile chronic arthritis. A total daily dose of about 40 mg of ibuprofen per kg of body weight (mean 37.1 mg/kg) was given in three portions. In serum the peak level was reached 1-2 hours after drug intake. The half-life of elimination in serum was 2.3 +/- 0.5 hours (mean +/- 1 S.D., n = 12). Twelve hours after the last dose the mean serum level was about 20 micromol/l. Ibuprofen concentrations fluctuated far less in synovial fluid than in serum. In synovial fluid peak levels (mean 65 micromol/l) were reached 5-6 hours after drug intake. Thereafter, the levels declined slowly but 12 hours later were still higher than in serum.