THE EFFICACY OF TREATMENT WITH METHOTREXA TE IN SYSTEMIC LUPUS-ERYTHEMATOSUS

BACKGROUND: To evaluate the efficacy of methotrexate in patients with systemic lupus erythematosus (SLE) without major organ involvement res istant to medium-high doses of prednisone. METHODS: Crossover, open cl inical trial with two treatment periods, the first of 3 months and the second of 6 months, an intermediate control period of 3 months and an other at the end of 6 months. A sample of 15 consecutive patients with SLE who, with no major organ damage, had active disease in spite of r eceiving more than 10 mg/day of prednisone or who relapsed on reductio n of this dosis during a period of at least 3 months. 7.5 mg/week of m ethotrexate were administered orally, divided into three doses of 2.5 mg/12 hours. Statistical significance was evaluated by Student's paire d t test and chi2; the strength of association by the Mantel-Haenzel o dds ratio (OR) method and the precision, by Miettinen's confidence int erval (CI). A p value of less than 0,05 was considered significant. RE SULTS: Two patients failed to finish the study; one for worsening of c utaneous lesions of necrotizing vasculitis which she already had previ ously, and the other for an increase in her transaminase levels. In th e remaining 13 there were 10 flares of disease activity during the con trol phases, 2 severe, versus 2 flares during the periods of methotrex ate use (OR 7.69 (95 % confidence interval, 1.67 to 33.33; p = 0.021). There were no significant changes in analytical results or prednisone requirements. During treatment six patients had oral aphthae and five had dyspepsia; three had an increase in transaminase levels, which in one caused the treatment to be stopped. There were two urinary infect ions, one community acquired pneumonia and one upper airway symptoms r equiring antibiotic treatment; one female patient had acute cholecysti tis with cholelithiasis necessitating surgical intervention. CONCLUSIO NS: Weekly low doses of methotrexate may prevent flares of activity of SLE in this type of patients, but it does not reduce the requirements of prednisone, nor modify analytical data. Toxic effects are rare and reversible upon interrupting medication.