Objectives: Fistulas in Crohn's disease remain a difficult clinical challenge. Rapid improvement with cyclosporine followed by deterioration after discontinuation of this drug has been reported. This study aimed to determine whether fast remission and long-term improvement could be achieved when cyclosporine was administered concurrently with azathioprine and low-dose prednisolone and then be discontinued.
Methods: Nine patients with fistulas were enrolled in this open study. For the first two weeks cyclosporine was administered intravenously at a dose of 5 mg/kg/day. Azathioprine and low-dose prednisolone were also given during this period. After two weeks cyclosporine was administered orally for a further ten weeks while azathioprine and a tapered dose of prednisolone were continued. Effectiveness was evaluated clinically, by a scoring system and by magnetic resonance imaging.
Results: With intravenous cyclosporine as part of this regimen, all nine patients went into remission within days. There were no recurrences after changing from intravenous to oral cyclosporine. Cyclosporine was terminated after three months while azathioprine and low-dose prednisolone were continued. Thereafter, four patients did not deteriorate, three deteriorated slightly, and two patients had a recurrence. The CDAI (Crohn's Disease Activity Index) improved from 200 (range 85-350) to 136 (range 26-200) by the end of the third month. Serological markers remained stable after discontinuation of cyclosporine. There were no serious side effects during this triple drug regimen.
Conclusions: The combination of cyclosporine, azathioprine and low-dose prednisolone leads to marked improvement of perianal fistulas in Crohn's disease. Remission occurs quickly under cyclosporine. These remissions can be maintained with azathioprine in a majority of patients.