Objective: We retrospectively examined the effect of combination therapy with prednisolone and cyclosporin A (CSA) for dermatomyositis (DM) presenting with acute/subacute interstitial pneumonia (A/SIP), the daily CSA dose, and the time from diagnosis of A/SIP to initiation of CSA treatment.
Methods: Subjects were 16 DM patients with A/SIP. Seven patients were treated initially with 1 mg/kg/day prednisolone. When IP was progressive, CSA was added (Group A). Nine patients were treated initially with 1 mg/kg/day prednisolone and 4 mg/kg/day CSA, and 2-h postdose blood concentration (C2) monitoring was used to maintain the serum CSA level at 1000 ng/ml (Group B).
Results: Four of 7 patients in Group A (57%) and 1 of 9 patients in Group B (11%) died of respiratory failure related to IP (p = 0.06). Combination therapy with prednisolone and CSA at >or= 200 mg/day initiated within 15 days of diagnosis was effective for treatment of DM-A/SIP. The trough level (C0) and daily CSA dose were higher in Group B (201.3 ng/ml and 200.0 mg/day, respectively) than in Group A (140.0 ng/ml and 166.4 mg/day). CSA was continued in all patients without severe side effects. No patient died of infection.
Conclusion: Combination therapy of corticosteroids and CSA should be initiated during the early stage of IP. The daily CSA dose should also be controlled with measurement of serum CSA concentration to achieve maximal immunosuppressive effect. C2 monitoring is a useful tool for this control.