Minimal mesangial lupus nephritis: a systematic review

Methods: We performed a systematic review of cases of MCN in SLE patients reported in the English literature from January 1985 to May 2009 by a Medline search. Results: The estimated prevalence of MCN in biopsy-proven lupus nephritis is 2.3% in childhood and 1.1% in adults. There are 13 individual cases (12 women, one man) of SLE-related MCN reported in the literature. The mean age of nephritis onset was 32.7 years. In six (46%) patients, MCN was the initial manifestation of SLE. All patients presented with nephrotic syndrome and two (15%) had active urinary sediments. Renal function was impaired in eight (62%) patients and six (46%) patients had active lupus serology. All patients responded promptly to high-dose glucocorticoids but four (31%) had relapse of proteinuria during their course of SLE. None of the patients developed thromboembolic or infective complications. Conclusions: MCN is an uncommon histological class of lupus nephritis. Typically, patients present with heavy proteinuria, and transient renal dysfunction is common. The prognosis of MCN in SLE appears to be good because of its rapid response to glucocorticoids. Relapses of proteinuria may be reduced by the use of maintenance immunosuppression. Alkylating agents, calcineurin inhibitors, mycophenolate mofetil, and rituximab can be considered in glucocorticoid-dependent or refractory cases of SLE-related MCN.