Secondary membranous nephropathy--one center experience.
BACKGROUND
Secondary membranous nephropathy (MN) is most commonly seen in the setting of autoimmune disease, infection, and neoplasia, and with certain therapeutic agents. The aim of our study was to analyze the presenting features and outcome of the patients with secondary MN.


METHODS
We retrospectively studied patients with secondary MN diagnosed between the years 1991-2002. In this period, we performed a total of 1874 renal biopsies. MN was diagnosed in 129 cases.


RESULTS
In 40 patients (31%), an underlying primary cause was verified (70% women, 30% men, median age 49.5 years). In 18 patients (45%), the disease was drug induced, 11 patients (27.5%) had autoimmune disease, seven patients (17.5%) solid tumors, three patients (7.5%) hepatitis B, and one patient was diagnosed with both hepatitis B and prostate carcinoma. At presentation, median proteinuria was 4.09 g/24 h; 60% were nephrotic. Most of the patients had normal renal function with a median serum creatinine 79 micromol/L and a median GFR 1.285 ml/s. The patients were treated according to the underlying disease. At the end of the follow-up, the patients with drug-induced MN were in complete remission after the discontinuation of the drug. The patients with autoimmune disease were treated with immunosuppression, most of them with very good results. The outcome of the patients with neoplasia was much worse.


CONCLUSIONS
A thorough and repeated exclusion of secondary forms of MN has significant prognostic and therapeutic implications, especially in drug-induced and autoimmune MN.
Rihova
Zuzana
Z
Nephrology Unit, 1st Medical Faculty, Charles University, Prague, Czech Republic. zrihova@centrum.cz
Honsova
Eva
E
Merta
Miroslav
M
Jancova
Eva
E
Rysava
Romana
R
Reiterova
Jana
J
Zabka
Jiri
J
Tesar
Vladimir
V
D000046:Academic Medical Centers; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001327:Autoimmune Diseases / Q000150:complications* / Q000175:diagnosis; D015331:Cohort Studies; D018153:Czech Republic / Q000453:epidemiology; D005260:Female; D015433:Glomerulonephritis, Membranous / Q000453:epidemiology* / Q000209:etiology*; D019694:Hepatitis B, Chronic / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D007674:Kidney Diseases / Q000139:chemically induced / Q000150:complications*; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications* / Q000175:diagnosis; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution