Download Clinical Outcomes in Idiopathic membranous nephropathy in Two

Declining renal function in idiopathic membranous nephropathy: a report from Two
Tertiary London Renal Units
Background
Idiopathic Membranous Nephropathy (IMN) is a major cause of the nephrotic syndrome in
adults. Renal function may deteriorate (progressor) or be preserved (non-progressor patients)
Methods
We performed a retrospective analysis of all patients with biopsy proven IMN under follow up
over the last 20 years.
Results
We identified 188 patients that had biopsy proven IMN under follow up during 1995-2015.
Median age
Male %
Ethnicity (White / Black / Asian / Unknown) %
Diagnosis Serum creatinine (sCr) (µmol/L)
Diagnosis Serum albumin (sAlb) (mmol/L)
Diagnosis urine protein creatinine ratio (PCR) (mg/mmol)
Spontaneous remission %
Renal replacement therapy (RRT) %
Deceased %
58 (44-71)
68
48 / 17 / 24 / 11
86.5 (64 – 111)
25 ± 7
900 (485 – 1255)
34
34
12
Of the 37 patients that spontaneously remitted, 5% relapsed. 20% of patients were progressors
(increase in sCr >50%, not on RRT). There was no statistical difference between sCr (101 ± 6
vs 92 ± 9 µmol/L, ns), sAlb (25.2 ± 1.3 vs 26.2 ± 0.8 mmol/L, ns) or PCR (893 ± 87 vs 895 ±
94 mg/mmol, ns) at diagnosis between progressors and non-progressors respectively.
Progressors were more likely to be Asian (36% vs 21%, p=0.058) and non-progressors black
(32% vs 20%, p=0.058).
65% of patients were treated with immunosuppressives. 60% received prednisolone, the most
frequently used first line agent was cyclophosphamide 35%, followed by anti-proliferative
agents 34% and calcineurin inhibitors (CNI) 23%. There was a significant difference between
treatment between progressors and non-progressors. Progressors were more likely to be treated
with CNI (38% vs 15%, p=0.04)
The complication rate from immunosuppression was 25%. The most common was diabetes
from steroid therapy at 10%. Infection occurred in 2% and drug specific complications in 7%.
Thromboembolism rate from nephrosis was low at 14%.
Conclusion
At diagnosis there was no significant difference in sCr, sAlb or PCR between progressors and
non-progressors. Progressor patients with IMN may benefit from immunosuppression, but this
is associated with risks.
In our cohort, the Asian population were more likely to be progressors. This differs to current
published data, possibly due to the predominance of Indian subcontinent population.
It is important to accurately identify progressor patients; there is an unmet need for a biomarker
to do this.