A Cochrane review included 4 studies with a total of 108 subjects. 3 studies investigated cyclosporin A (CSA) with or without prednisone versus prednisone or no treatment and one compared chlorambucil plus prednisone versus no treatment. Outcome data was only available for complete or partial remission and doubling of serum creatinine. No data was available on the progression to kidney failure or death. Pooled analyses were not performed due to the heterogeneity of the data.
There was a significant increase in the number of participants who obtained complete or partial remission with CSA plus low dose prednisone versus prednisone alone (RR 8.85, 95% CI 1.22 to 63.92¸ 1 study, n=49). There was no significant differences in the number of patients with complete or partial remission of proteinuria in the 3 other studies comparing CSA + prednisolone versus methylprednisolone¸ CSA versus no treatment, and prednisolone + chlorambucil versus no treatment. Among the CSA trials, the addition of CSA seemed to increase the number of patients with complete of partial remission of proteinuria, however this increase was not significant (RR 2.15, 95% CI 0.98 to 4.73; 3 studies, n=93).
Only three studies reported data on kidney function. There was no significant difference in the number of patients with doubling of serum creatinine between the groups.
Comment: The quality of evidence is downgraded by inconsistency (heterogeneity in interventions and outcomes) and by imprecise results (few patients and wide confidence intervals). The authors state that there is a probability of deterioration of kidney function due to the nephrotoxic effect of CSA in the long term, and a longer follow-up is needed to prove the benefit of this regimen not only on proteinuria but also on the preservation of kidney function.