G. J. Tobon1, C. D. Ochoa1, C. A. Canas2
1Internal Medicine, 2Rheumatology, Fundacion Valle del Lili, Cali, Colombia

Background: The inflammatory myopathies represent the largest group of the muscle disorders, with unknown etiology. High esteroid dose are the first line treatment in these patients associated with significant adverse events. Immunosuppressive agents and immunomodulatory therapy are used to improve disease control and reduce the long-term side effects of corticosteroids. While these treatments are used commonly in routine clinical practice, the optimal therapeutic regimen remains unclear. The initial treatment with a combined regimen of steroid and immunosuppressive treatment has been evaluated in few studies.
Objectives: To assess the clinical response, laboratory findings and sparing-steroid effect of a combined regimen of prednisone, cyclosporine and methotrexate in patients with inflammatory myopathies at onset of the treatment.
Methods: Twelve patients with inflammatory myopathy, according to Boham and Peter’s criteria were treated at onset with prednisone and immunosuppressive agents (cyclosporine, methotrexate), in the Fundación Valle del Lili, Cali (Colombia). Clinical data and laboratory findings were registered in successive visits at onset, three, six and twelve months, respectively. Muscle straight were evaluated in a scale from 0 (no contraction) to 5 (normal function). Quality of Life (QOL) were evaluated in a range from 1 (normal activities) to 4 (with important limitation). Statistics in means, standard deviation and percentages are presented.

Results: Twelve patients with inflammatory myopathies were included (eight patients with dermatomyositis (66.6%) and four patients with polymyositis (33.3%). Mean age was 42.4 +/- 17.98 years. Nine patients were woman (75%). The main clinical manifestations were muscle weakness in eleven patients (91%), skin involvement in eight patients (66%), heart involvement in one patient (8.3%), pulmonary in 2 (16.6%), joint involvement in one (8.3%), dysphagia in four (33.3%) and vasculitis in one patient (8.3%). Creatin-Kinase levels at onset were 4.797 +/- 3927 mg/dL. Muscle straight was 3 +/- 1.8 and QOL was 3 +/- 0.85. INITIAL TREATMENT: Seven patients were treated with steroid pulses (methyl-prednisolone 750 mg/day for three days). All patients received prednisone (dose: 0.7 +/- 0.3 mg/kilogram/day). Seven patients were treated with cyclosporine (3 mg/kg/day), nine with methotrexate (15 mg/wk). Prednisone was reduced in a gradually fashion according to the clinical improvement. Clinical, laboratory and QOL results are reported in Table 1. At twelve months, ten patients (83.3%) were in remission (normal levels of creatin-kinase and muscle straight). None patient has steroid myopathy or serious adverse events.
(in months)
Steroid dosage
Creatin-kinase levelsMuscle Straight (0-5)Quality of Life (1-4)

Onset0.7 ± 0.34797 ± 39273 ± 1.83 ± 0.85
Three months0.7 ± 0.3616.6 ± 10173.91 ± 1.042.01 ± 1.04
Twelve months0.2 ± 1.2260 ± 6094.8 ± 0.421.3 ± 0.48

Conclusion: Combined treatment with prednisone, cyclosporine and methotrexate seems to be effective, safe and well tolerated in patients with inflammatory myopathy. A good response was seen in terms of muscle straight, QOL, creatin-kinase levels and reduction in steroids dosage. The mechanism of action of cyclosporine and methotrexate in inhibition of T cell, highlight the role of this latter in the pathogenesis of inflammatory myopathy.