The effect of methotrexate and azathioprine on the serum levels of IgA-alfa1-antitrypsin complex in juvenile chronic arthritis

ABSTRACT

In the present study we investigated the influence of methotrexate (MTX) and azathioprine (AZA) on the serum levels of the IgA-alpha1-antitypsin (IgA-AT) complex in patients with the systemic form of juvenile chronic arthritis (JCA). Fifty-six JCA patients (22 treated with MTX, 18 treated with AZA, and 16 not treated with any immuno-suppressive agent) were enrolled in the study. MTX dosage ranged from 0.3 to 0.5 mg kg(-1) week(-1) while AZA was given daily at an average dose of 1 mg/kg. MTX was given for 13 months (SD = 7 months) whereas AZA for 11 months (SD = 6 months). The average value of the complex was higher in JCA patients than in both control groups (0.74 + 0.73 U vs 0.37 + 0.13 U (control children), P<0.001 and vs 0.23 + 0.12 U (control adults), P<0.001). Values exceeding the normal range were found in twenty-two JCA patients (39.4 percent). Serum IgA-AT level was lowest in the MTX group compared to AZA and non-treated patients (0.56 + 0.24 U, 0.76 + 0.43 U, 0.95 + 0.52 U, respectively, P<0.05). IgA values exceeding normal levels for age were found in 14 percent of the patients. A correlation between the levels of the IgA-AT complex and C-reactive protein (r = 0.43, P<0.01), alpha1-acid-glycoprotein (r = 0.45, P<0.01), alpha1-antichymotrypsin (r = 0.52, P<0.01), alpha1-antitrypsin (r = 0.40, P<0.01) and IgA (r = 0.56, P<0.01) was established.