From the Guidelines
IgA nephropathy classified as M0 E1 S1 T0 C1 indicates a specific disease severity and treatment approach.
Disease Severity Classification
- The "M0" suggests no mesangial hypercellularity 1,
- "E1" indicates endocapillary hypercellularity 1,
- "S1" signifies segmental glomerulosclerosis 1,
- "T0" denotes no interstitial fibrosis/tubular atrophy 1,
- and "C1" represents crescents in less than 50% of glomeruli 1.
Treatment Approach
Treatment may involve RAS blockade as much as tolerated or allowed, with blood pressure control, cardiovascular risk minimization, adherence to lifestyle advice, including dietary counselling, smoking cessation, weight control, and exercise as appropriate 1. If proteinuria stays above 0.75–1 g/d despite at least 90 days of optimized supportive care, the patient has a high risk of progressive loss of kidney function and may be considered for a 6-month course of glucocorticoid therapy 1.
From the Research
IgA Nephropathy Classification
The M0 E1 S1 T0 C1 classification in IgA nephropathy refers to a specific set of histological features observed in kidney biopsies. These features are:
- M0: Mesangial hypercellularity is absent (less than 50% of glomeruli) 2, 3
- E1: Endocapillary hypercellularity is present 2, 3
- S1: Segmental sclerosis is present 2, 3
- T0: Tubular atrophy/interstitial fibrosis is less than or equal to 25% 2, 3
- C1: At least one crescent is present 2
Clinical Significance
The presence of these features can help predict the risk of progression to end-stage kidney disease (ESKD) in patients with IgA nephropathy. For example, the presence of crescents (C1) has been associated with an increased risk of ESKD 2. Additionally, the combination of tubular atrophy/interstitial fibrosis (T1) and crescents (C1) has been shown to strongly predict a high risk of ESKD 2.
Key Features
The key features of the Oxford classification of IgA nephropathy, which includes the MEST-C score, are: