[Successful cyclosporine treatment in 2 patients with refractory CIDP, involving monitoring of both AUC(0-4h) and trough levels].

Cyclosporine A (CYA) treatment has been reported to be probably useful for patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) that is resistant to conventional treatment. Although several studies have shown that appropriate area under the concentration-time curve (AUC) monitoring of CYA levels results in improved outcomes for refractory nephrotic syndrome patients, the importance of using AUC analysis for CIDP remains unclear. In this study, we measured both trough and AUC from 0 to 4 h (AUC(0-4 h)) levels of CYA in 2 patients with CIDP and compared the findings for the clinical parameters. On the basis of the CYA dosing recommendations for patients with nephrotic syndrome, we used a CYA concentration of 150 ng/ml for the trough level and an AUC(0-4 h) value of 2,500 ng/(ml·h). Patient 1 showed a significant increase in grip strength and a prolonged remission period. Patient 2 showed improvement in the modified Rankin scale and manual muscle test (MMT) scores. Monitoring both AUC(0-4 h) and trough levels of CYA seems to be a better option than monitoring the trough level alone because it leads to improved estimation of the efficacy and safety of CYA treatment in the case of CIDP patients.