DEXAMETHASONE-AZATHIOPRINE PULSE THERAPY AS AN ALTERNATIVE TREATMENT MODALITY IN PEMPHIGUS WITH DEXAMETHASONE-CYCLOPHOSPHAMIDE PULSE THERAPY FAILURE: A RETROSPECTIVE OBSERVATIONAL STUDY
Background: Dexamethasone Immunosuppressant Pulse therapy has been widely accepted as a promising treatment for treating Autoimmune Vesico-bullous diseases. Dexamethasone-Cyclophosphamide Pulse (DCP) therapy has been reported to have better remission rate in Pemphigus patients as compared to Dexamethasone-Azathioprine Pulse (DAP) and Dexamethasone-Methotrexate Pulse (DMP) therapy, but few cases may prove to be resistant to DCP therapy. Rituximab is one of the modalities preferred for treatment in such resistant cases.
Aim: To study role of DAP therapy in Pemphigus patients with DCP therapy failure.
Materials and Methods: Records of Pemphigus cases between January 2014 to December 2019 were analyzed retrospectively. Cases who received DAP therapy after failures to achieve remission inspite of receiving 12 DCPs earlier were included in the study.
Results: It was observed that after shifting on DAP therapy all 6 patients achieved clinical remission within mean duration of 4 months of phase-1. Presently all these patients are in phase-4 of DAP therapy without recurrence.
Conclusion: Treatment failure with Cyclophosphamide could be due to resistance to Cyclophosphamide which may occur due to decreased cellular penetration, improved DNA repair or increased drug metabolism. In such cases of failure, Azathioprine may be effective due to its structural similarity to endogenous purines. It incorporates into DNA and RNA, inhibiting purine metabolism and cell division. It also decreases antibody production by B-cells. Decreased antibody production due to different mechanism of action could be the reason for good response in patients with Cyclophosphamide resistance. In such cases DAP therapy can be considered for effective treatment of this disease in patients with financial constraints.
Keywords: Dexamethasone-Azathioprine Pulse(DAP), Dexamethasone-Cyclophosphamide Pulse(DCP), Pemphigus.