Atypical IgA Nephropathy

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1 Atypical IgA Nephropathy Richard J. Glassock, MD, MACP Geffen School of Medicine at UCLA XXXIII Chilean Congress of Nephrology, Hypertension and Transplantation Puerto Varas, Chile October 6, 2016

2 IgA Nephropathy: Typical Presentations Recurrent episodes of microscopic or macroscopic (glomerular) hematuria and mild or overt proteinuria with initially normal renal fuction Slowly progressive chronic kidney disease, accompanied by asymptomatic (glomerular) hematuria and moderate proteinuria

3 IgA Nephropathy: Atypical Presentations Nephrotic Syndrome with Minimal Change Disease lesions Rapidly progressive glomerulonephritis with extensive crescentic lesions Acute Kidney Injury (reversible) with macroscopic hematuria and intra-tubular haemorrhage with minor crescentic disease Atypical Hemolytic-Uremia syndrome Malignant Hypertension Super-imposed Warfarin-Nephropathy

4 IgA N, Nephrotic Syndrome and Minimal Change Lesion Uncommon (<2% of all IgA N) May be co-incidental rather than causal relationship (up to 14% of normal healthy subjects have lanthamnic IgA deposits (± C3) in their kidneys Behaves almost exactly as Primary Minimal Change Disease (MCD) without IgA deposits

5 IgA N with MCD (Herlitz LC, et al. CJASN; 2014; 9: )

6 Glomerular IgA Deposits in Normal Individuals (Transplant Donors; Accidental and Suicidal Deaths) 16% 14% 12% 10% 8% 6% 4% 2% 0% IgA Deposits Japan Switzerland Finland Singapore Germany Average

7 Comparison of Primary MCD (n=77) and IgAN with MCD (n=77) (Li XW, et al Clin Nephrol 2016; 85: ) IgA + MCD Young males Nephrotic syndrome ± hematuria Reduced egfr Very low serum albumin Higher M1 scores Partial steroid resistance (12% no CR) No ESRD after 4 years of FU MCD Only Young males Nephrotic syndrome ±hematuria Usually normal or elevated egfr (AKI in older adults) Minimal M0-M1 scores Minimal steroid resistance (9% no CR) No ESRD after 4 years of FU

8 IgA N with MCD Therapy (Herlitz LC, e al CJASN 2014; 9: ) Complete response off all therapy (n=9) Complete response on therapy (n=5) Partial response on therapy (n=3) Initial Steroid therapy Relapses or treatment dependence

9 IgA N with MCD Conclusions Very closely resembles Primary MCD Perhaps more hematuria, reduced egfr and mesangial prominence (M1). Mesangial ED deposits. Response to steroids (and adjunctive agents) and long-term course very similar to MCD? Two diseases or one?

10 Crescentic IgA Nephropathy May be a forme fruste of IgA Vasculitis (Henoch-Schonlein Purpura)- occasional; patients are ANCA + (IgG or IgA ANCA, usually anti-mpo) Some crescents are found in about 36% of all biopsies showing IgA N The magnitude of crescentic involvement has both prognostic and therapeutic significance

11 IgA Nephropathy: Pathologically heterogeneous (Roberts, et al ASN CNC. 2008)

12 Crescentic IgA N: Distribution of % Crescents among those with any crescents (n=1118) (Haas, M, et al JASN, 2016)

13 Crescents in IgA N (Haas M, et al JASN, 2016;28- n= 3096 biopsies) NONE- 64% ANY- 36% 1/12 27% 1/10-21% 1/8-16% 1/7-14% 1/6-11% 1/5-6.9% 1/4-4.8% 1/2 - <0.2% Minor crescentic involvement (<10% of glomeruli affected) is common in IgA N (14% of all cases) Severe crescentic involvement (>25% of glomeruli affected) is uncommon in IgA N (3% of all cases)

14 Crescentic IgA N Prognosis (Haas M, et al JASN; 2016) Any crescents indicate a more rapid rate of progression, but this is also partiallypredicted by MEST score, independent of crescents, but only in non-immunosuppressed patients (HR for ESRD= 1.51 [CI= ] for no immunosuppression and 1.13 [CI= ] for immunosuppression) The threshold for an adverse effect of crescents on ESRD outcome (in non-immunosuppressed patients only) appeared to be around 1/6 (17%) to 1/4 (25%) of glomerular involvement

15 Crescentic IgA N: Outcome (Haas, M, et al JASN, 2016)

16 Crescentic IgA N Prognosis (Haas M, et al JASN; 2016) Discrimination of performance of models for prediction of survival at 10 years for a renal event No Immunosuppression- MEST score- initial egfr, and proteinuria- N/A + any crescents- 0.2 (p=0.02) Immunosuppression- MEST score, initial egfr, proteinuria- N/A + any crescents (p=0.78) These differences suggest, but do not prove, that IS is efficacious in IgA N with crescentic involvement

17 PROPOSED ADDITION TO MEST SCORING (Hass M, et al, 2016) C0= no crescents C1= crescents present in less than ¼ of the glomeruli C2= crescents present in over ¼ of glomeruli

18 Crescentic IgA N: Therapy Evidence base is very weak (Grade C or D) concerning benefits and risks of treatment of crescentic IgA N (C1 or C2) Rapidly progressing GN or egfr <30ml/min/1.73m2 have been exclusions in most RCT Impact of crescents not a part of RCT evaluations

19 Treatment Modalities for Crescentic IgA N Pulse methyl prednisolone, oral prednisone and oral or IV cyclophosphamide (AAV protocol) Pulse methylprednisolone, oral prednisone and Rituximab (RAVE protocol) Pulse methylprednisolone, oral steroids and MMF or Leflunomide One of the above plus PLEX

20 Adjunctive use of PLEX in Crescentic IgA N (Xie X, et al, Am J Nephrol 2016; 44: ) Uncontrolled, observational study of patients with advanced crescentic IgA N treated with PLEX + IS (n=12; average 7 sessions) compared to propensity matched historical controls treated only with IS (n=12) PLEX + IS Crescents= 64%; initial Scr= 8.0mg/dL, Dialysis dependent= 66% IS ONLY Crescents= 69%; initial Scr= 7.5mg/dL; dialysis-dependent= 75%

21 PLEX IN CRESCENTIC IgA N Outcomes at 6 months (Xie X, AJN, 2016) PLEX + IS (n=12) Alive free of dialysis- 5 IS Only (n=12) Alive free of dialysis- 0 Death- 1 Deaths- 3 ESRD requiring dialysis- 7 ESRD requrig dialysis-12

22 THANK YOU!!!

23 LUPUS PODOCYTOPATHY