Pediatric Rheumatology Online Journal → July 2003 → Dermatomyositis → Treatment → Abstract #123

INITIAL TREATMENT OF JUVENILE DERMATOMYOSITIS(JDM) USING METHOTREXATE(MTX) AND AGGRESSIVELY TAPERED PREDNISONE(PRED)

A. V. Ramanan,1 N. Campbell-Webster,1 D. Tran,1 P. N. Tyrrell,1 B. Cameron,1 R. M. Laxer,1 R. Schneider,1 L. Speigel,1 B. M. Feldman.1

1Division of Pediatric Rheumatology, Hospital for Sick Children, Toronto, ON, Canada

Traditional treatment with long term PRED has significant side effects. Our initial small pilot study suggested that MTX as a 1st line therapy could successfully spare steroid use.
Aim: To determine the long term efficacy and safety of MTX when combined with short course PRED as a 1st line therapy.
Methods: An inception cohort of all 30 JDM patients seen since June 97 was treated with MTX at onset. We studied 20 consecutive JDM controls from 93 97; follow up protocol was identical. The study group got MTX (10-20mg/m/week) and PRED 2mg/kg/day. At 6 weeks PRED was tapered by 10% every 2 weeks. The control group was treated with PRED 2mg/kg/day but tapered at 10% per month. All controls were followed for 4 years(960 pt.months); 12 study pts were followed for 4 years, 2 for 3-4 years, 11 for 2-3 years, 2 for 1-2 years and 3 for less than 1 year(1033 pt. months).
Results: At baseline, age at onset, sex, race and body mass index (BMI) were similar; both groups had similar moderate disability.
The median time on PRED for the study group was shorter than the control group (10 months vs. 27 months, p0.001). The treatment group had less weight gain at 1 year (median increase in BMI 2.3 kg/mvs. 5.1 kg/m, p=0.002 ) and a better height velocity (5 cm/yr vs. 2.5 cm/yr, p=0.046). Only one patient was taken off MTX for toxicity.
Function (CHAQ, ACR functional class, mean muscle power) was excellent in both groups at 1 year.
At 2, 3 and 4 year follow up there were no statistical difference in function, CHAQ, muscle power or rash. Of the patients followed for 4 yrs there were no differences between controls and subjects in calcinosis (25%vs17%), cataracts(35%vs8%) and disease flares(40vs42%).Spinal fractures were seen in 1 patient in each group.
Conclusion: Treatment with MTX and short course of PRED is likely as effective and is associated with fewer short term side effects than traditional long term PRED therapy.