In our study [1], nine patients completed the 6-month pulse cyclophosphamide therapy, a number that approaches that of the study by Bircan and Kara [2]. However, only one (11.1%) of them has maintained remission 2 years after stopping cyclophosphamide. Additionally, in the earlier study concerning oral cyclophosphamide in steroid-dependent nephrotic patients [3], despite the fact that steroids were continued throughout the 12-week cyclophosphamide course, the authors concluded that it is unlikely that this could be responsible for better results according to their earlier study in 1981. On the other hand, cumulative steroid dose was higher in the study by Bircan and Kara [2]. Also, the protocol of steroid withdrawal after stopping cyclophosphamide and the percentage of patients that became steroid independent were not mentioned. Moreover, the claim that long-term side effects were absent cannot be completely accepted if there was no testing for gonadal toxicity.
Actually, we are sceptical about the conclusion in Bircan and Kara's study [2] that intravenous cyclophosphamide is the drug of choice for steroid-dependent nephrotic syndrome. Nevertheless, it remains possible that previous adjunctive therapy, renal pathology (neither of which were indicated in the study by Bircan and Kara), racial and genetic factors and selection criteria have an effect on the results obtained.
Conflict of interest statement. None declared.
Urology and Nephrology Center Mansoura University Mansoura Egypt Email: afdonia{at}hotmail.com
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