Membranous nephropathy may occur secondary to conditions such as systemiclupus erythematosus （SLE）， drug therapy （gold, penicillamine, NSAIDs etc）， hepatitisB, malaria, schistosomiasis, syphilis and other infections, diabetes, thyroiditis andcertain malignancies （Brueggaemeyer et al 1987）。 In one series of 82 consecutiveCaucasian adults with MGN, secondary causes were identified in 17 patients （21%）including drugs, malignancy in four, thyroiditis, syphilis and hepatitis B virus infection（Cahen et al 1989）。
Databases searched: MeSH terms and text words for secondary membranousnephropathy. This search was carried out in Medline （1966 to September Week 12004）。 The Cochrane Renal Group Trials Register was also searched for trials ofmembranous nephropathy not indexed in Medline.
Date of searches: 9 September 2004.
What is the evidence?
There have been no randomised controlled trials.
Summary of the evidence
No recommendations can be made on the basis of current anecdotal evidence.
What do the other guidelines say?
Kidney Disease Outcomes Quality Initiative:No recommendation.
UK Renal Association: No recommendation.
Canadian Society of Nephrology: No recommendation.
European Best Practice Guidelines: No recommendation.
International Guidelines: No recommendation.
Implementation and audit
Suggestions for future research