Monoclonal gammopathy- associated renal lesions Sanjeev Sethi, MD, PhD 2 nd International Renal Conference Brugge 2018 Sanjeev Sethi, MD, PhD Department of Laboratory Medicine and Pathology
Monoclonal gammopathy-
associated renal lesions
Sanjeev Sethi, MD, PhD
2nd International Renal Conference Brugge 2018
Sanjeev Sethi, MD, PhD
Department of Laboratory Medicine and Pathology
Immunoglobulin G molecule
Paul Sanders, University of
Alabama at Birmingham
Some background�
• Intact Ig not filtered through glomerular capillary
walls
• Free light chains: approx. 500 mg/day are • Free light chains: approx. 500 mg/day are
produced by lymphoid tissue, and small
amounts of light chain filter through, most are
reabsorbed by proximal tubules
Glomerular ultrafiltration of
macromolecules (““““classical view””””)
Paul Sanders, University of
Alabama at Birmingham
Monoclonal Gammopathy
• The term monoclonal gammopathy refers to the overproduction of a monoclonal Ig (MIg) resulting from the clonal proliferation of immunoglobulin (Ig)-producing plasma cells or B lymphocytes .
• In most patients, the Ig is detected in the blood or the urine as a monoclonal Ig (monoclonal (M) protein)
• In most patients, there is also secretion of the light chain component • In most patients, there is also secretion of the light chain component of the Ig molecule (kappa or lambda light chains) in addition to the intact heavy Ig, e.g. IgGκ, IgMλ, etc., suggesting dysregulation of the normal antibody synthetic pathways
• In some instances, the neoplastic cells lose the ability to synthesize the normal heavy chain component of the Ig molecule, and instead secrete only kappa or lambda light chains
Laboratory techniques for detection of MIg
• Serum (S) and urine (U) protein electrophoresis (PEP)-Band or a
peak
• Immunofixation electrophoresis (IFE)- use of antibody to identify the
specific MIg
• Serum free light chain (FLC) assays provide a sensitive quantitation • Serum free light chain (FLC) assays provide a sensitive quantitation
of total serum free (unbound) kappa light chain and lambda light
chain-The presence of a kappa clone or lambda clone is inferred
from an abnormal ratio
•
• Bone marrow biopsy and aspiration Tissue detection of the plasma
cell or B lymphocyte clone requires a bone marrow biopsy and
aspiration, lymph node biopsy or extranodal biopsy, as appropriate,
with adjunct flow cytometry and molecular immunophenotyping.
Hematologic conditions associated with
Monoclonal Ig-Renal Disease
Plasma cell dyscrasia B cell lymphoproliferative disorders
Malignant Non malignant/ Malignant Non malignant/Malignant Non malignant/
premalignantMalignant Non malignant/
premalignant
Waldenström
macroglobulinemia
Multiple
Myeloma/
plasmacyto
ma
MGRS B-cell lymphoma/leukemia MGRS
(Dangerous
B-cell clones)
Smoldering
multiple
myeloma
Diagnostic Criteria of Plasma Cell Dyscrasias
MGUS SMM MM
M-spike < 3 g/dL ≥ 3 g/dL ≥ 3 g/dL
Bone Marrow PC < 10% ≥ 10% ≥ 10%
Hypercalcemia (C) absent absent +/-
Renal impairment (R) absent* absent +/-Renal impairment (R) absent* absent +/-
Anemia (A) absent absent +/-
Lytic lesions (B) absent absent +/-
Kyle et al. Leukemia 2010
Talamo et al. Clin Lymphoma, Myeloma & Leukemia. 2010
Treatment Not recommended Only high risk Yes
Criteria for MGUS, MGRS, SMM and MM
MGUS MGRS Smoldering
multiple myeloma
Multiple
myeloma
<10% BMPC
AND
<10% BMPC
AND
≥10%-60% bone marrow
plasma cells
OR
•Clonal plasma cell
disorder, AND 1 or
more of following MDE:
≥60% BMPC
<3 gm/dL M protein <3 gm/dL M protein
AND
≥3 gm/dL serum M protein
OR
≥500 mg/24h urinary M
protein
≥100 FLC ratio
No end organ
damage
MIg-associated renal
disease
End organ may be involved CRAB features
(hypercalcemia, renal
failure, anemia and
bone lesions)
>1 MRI focal lesion
No myeloma
defining event
(MDE)
No MDE No MDE MDE present
MGRS= Monoclonal gammopathy of renal significance;
MIg causing renal disease in the absence of a malignancy-
SMM/MM/Lymphoma/LeukemiaSethi S, Rajkumar V, D’Agati V
submitted
Sethi S, Rajkumar V, D’Agati V
submitted
Sethi S, Rajkumar V, D’Agati V
Light chain proximal tubulopathy
Monoclonal Ig-associated renal lesions
Paul Sanders, Birmingham, AL
(NKF, 2012)
• Amyloidosis
• PGNMID
• MIDD
• Immunotactoid/fibrillary GN
Cast nephropathy
76%76%
Patient # 1
• 61-year old man presented with acute renal failure and back
pain.
• Serum creatinine 13.8 mg/dL.
• UA 2+ protein and 2+ blood.
• All serology's including ANCA were negative• All serology's including ANCA were negative
• Serum electrophoresis showed an M spike, urine and serum
immunofixation showed IgG lambda
Hyaline vs. myeloma casts
lambda
In this case, casts stain for lambda light
chains, and are negative for kappa light chains
Cast nephropathy, lambda light chain type
kappa
• Kidney, needle biopsy: Cast nephropathy (myeloma
kidney), lambda light chain type
- Casts form due to interaction of the filtered light chains with Tamm-
Horsfall proteinHorsfall protein
- a binding domain for FLC on THP, varying affinity
– Myeloma cast nephropathy is most common renal lesion associated
with MM, and more than 90% of the patients with cast nephropathy
have MM. Cast nephropathy is considered a myeloma-defining event,
and hence is incompatible with a diagnosis of MGUS/MGRS
Patient # 2
• 69-year old man with hematuria, proteinuria, and
acute renal failure
• Serum creatinine 2.04 mg/dL
• Urinary protein 2.8 gms/24 hours• Urinary protein 2.8 gms/24 hours
• Electrophoresis studies show lambda light chains
Differential diagnosis of
nodular glomerulosclerosis
1. Amyloidosis
2. Diabetes
3. MPGN
4. Chronic TMA
5. And this lesion
kappa
lambda
Kidney, needle biopsy: Light chain deposition
disease, lambda light chain type
– Exposed portions of light/heavy chains, that allows for spontaneous
oligomers and aggregates to form
– Cationic isoelectric points which may favor binding to basement
membranes
– Activate mesangial cells to secrete matrix– Activate mesangial cells to secrete matrix
– In a recent study, >95% of the patients have a detectable monoclonal
gammopathy, and 59% of the patients had MM.
– In another study of 34 patients of MIDD, 39% of the patients had MM
and 39% were diagnosed with MGRS. In approximately 10% of the
patients no hematological abnormality is detected.
Patient # 3
• Mr. DR is 71 year old man with history of diabetes presenting
with increasing proteinuria and edema
• Serum creatinine 1.6 mg/dL, urinary protein 9 grams/day
• Serum electrophoresis showed an M spike, urine and serum
immunofixation showed IgG lambdaimmunofixation showed IgG lambda
• Renal biopsy done to find the cause of nephrotic syndrome
PAS negative mesangial nodules
Congo red positive
Lambda Lambda
Kappa Kappa
Kidney, needle biopsy:
AL Amyloidosis,
lambda light chain
type, involving
glomeruli, interstitium
and vessels
8.2 nm in thickness
• Kidney, needle biopsy: AL Amyloidosis, lambda light chain type, involving glomeruli, interstitium and
vessels
– Over 95-98% of patients with systemic AL/AH amyloidosis will have a
detectable M protein on serum or urine protein immunofixation, or an
abnormal serum free light chain ratio. In the small percentage of abnormal serum free light chain ratio. In the small percentage of
patients in whom evidence of a monoclonal process is not apparent on
these studies, a bone marrow biopsy will show evidence of clonal
plasma cells.
Patient # 4
• Mr. SS is a 66 year old man who has a past medical history of urinary abnormalities characterized by nephrotic range proteinuria, microscopic hematuria, and hypertension.
• He now presents with generalized edema, proteinuria of 6.7 gms/24 hours. Urinary sediment shows numerous RBC’s, hyaline and waxy casts. Serum creatinine 1.4 mg/dl. Serologies hyaline and waxy casts. Serum creatinine 1.4 mg/dl. Serologies for ANA, hepatitis, cryo’s are negative. Low C3 and C4 levels.
Clinical Syndrome: �ephrotic/nephritic syndrome
• Renal Biopsy was done
C3
Proliferative GN due to monoclonal Ig deposition
(PGNMID): IgM kappa
Proliferative GN due to monoclonal IgG kappa
deposition (PGNMID)
C3IgG C3
kappa lambda
IgG
58-year old man with nephrotic syndrome, hypertension, hyperlipidemia and edema.
Serum creatinine 1.6 mg/dL, UA- large amounts of blood, Urine IFE kappa light chains
IgG subtyping- IgG3
Low grade B cell
lymphoma
Lymphoplasmacytic/
Waldenström’’’’s lymphoma
Proliferative GN associated with monoclonal
gammopathy
MGRSMultiple
Myeloma
Chronic lymphocytic leukemia
Hematologic Characteristics of Proliferative Glomerulonephritis
with Monoclonal Immunoglobulin Deposits (PGNMID)
• In cases with monoclonal IgG, subtyping for the IgG isotypes (1-4) is helpful
to confirm the diagnosis by demonstrating gamma subtype restriction.
• IgG3 is the most common subclass: this subclass is most likely to have
undetectable M-protein in serum and urine
• Only 20-30% of patients with PGNMID have a detectable M-protein in • Only 20-30% of patients with PGNMID have a detectable M-protein in
serum or urine, mostly IgG1 or IgG2 subclass, but associated hematologic
malignancy is extremely rare.
• The circulating pathologic MIg was most commonly detected on serum
immunofixation (20%; SIFE+) and by abnormal serum free light chain ratio
(19%; sFLCR+).
• Negative SIFE and sFLCR had a 100% negative predictive value for
detectable BM clone.
Progression of Renal Disease and Treatment Outcomes in
PGNMID
•At 1 year point, 40% had ESRD or
doubling of creatinine.
•No relationship was observed between
renal survival and detectability of
pathologic Ig or clone, Ig isotype, IgG
subtype, light chain, age or gender.
Patient # 5
• 61-year old man with monoclonal gammopathy (IgG kappa
protein with M spikes, 0.5-0.9 g/dL), low complement titers
(low C3, normal C4), and gross hematuria, few RBC casts.
Serum creatinine 1.3 mg/dL
• Bone marrow 8% plasma cells: MGUS
• Biopsied in 07 and 09
Mesangial &
Endocapillary
proliferation
Double contours
C3
Mesangial deposits
IgA, IgG, IgM, C1q, kappa and lambda light chains- negative
C3 glomerulonephritis, associated with a
monoclonal gammopathy
Mesangial depositsCapillary wall deposits: subendothelial
and subepithelial deposits
Patient # 6: DDD associated with a monoclonal
gammopathy• 58-year old woman presented with hypertension and chronic kidney disease.
• Serum creatinine 3.45 mg/dL, low C3 and normal C4 level, urinalysis showed 3+ RBC and 3+ protein, UA-25 RBC/HPF
• On dialysis, Work up showed a monoclonal gammopathy of 0.4 mg/dL (IgG kappa)
C3
All Ig’s are negative
C3 glomerulonephritis and MGUS: 32 Mayo Clinic patients :10 (31%) had evidence
of monoclonal Ig. American Journal of Kidney Diseases, 2013
DDD and MGUS: 71.4% of patients 49
years and older in whom DDD was
diagnosed on kidney biopsy also carried an
established diagnosis of MGUS,
American Journal of Kidney Diseases,
2010
Ravindran A, Fervenza F, Smith R, Sethi S
In press
Mechanism of action in C3 glomerulopathy
• Monoclonal Ig may inhibit regulation of the AP of complement by
acting as C3 nephritic factor or by interfering with the function of
complement regulatory proteins such as factor H
• Unique subset of C3G-MIg patients:
– Older patients of C3G– Older patients of C3G
– Presence of autoantibodies: C3Nef was detected in 45.8%
patients
– Pathogenic variants in complement protein genes were rare.
– MIg-targeted treatment may result in remission and stabilization
of the kidney function in a subset of these patients.
Renal and Hematological outcomes of C3G
patients with MIg-targeted therapy
X
Proliferative Glomerulonephritis
IF: Monotypic Ig deposits, with or
without C3
IF: C3 deposits,
absence of monotypic Ig deposits
Indirect mechanismDirect mechanism
DDD or C3GN
Positive for
circulating
monoclonal Ig
Negative for
circulating
monoclonal Ig
Positive for
circulating
monoclonal Ig
Kidney biopsy report• Cast nephropathy (myeloma kidney), (no designation of the
hematologic disease required because this diagnosis is MM-defining)
• AL-amyloidosis, multiple myeloma-associated
• AL-amyloidosis, plasmacytoma-associated
• AL-amyloidosis, B-cell lymphoma-associated
• Light chain deposition disease, smoldering multiple myeloma-
associated
• Light chain deposition disease, B-cell lymphoma-associated
• Light chain deposition disease, MGRS-associated
• Cryoglobulinemic glomerulonephritis, Waldenström
macroglobulinemia-associated
• Cryoglobulinemic glomerulonephritis, chronic lymphocytic leukemia-
associated
• C3-glomerulonephritis, MGRS-associated
• Crystal storing histiocytosis, B-cell lymphoma-associated
• Light chain proximal tubulopathy, MGRS-associated
• Immunotactoid glomerulopathy, lymphoplasmacytic lymphoma-
associated
• Proliferative glomerulonephritis with MIg deposits, MGRS-associated
• Thrombotic microangiopathy, MGRS-associated
• Proliferative glomerulonephritis with MIg deposits, with no
demonstrable serum/urine MIg
• Light chain deposition disease, hematological evaluation pending
The Complexity and Heterogeneity of Monoclonal Immunoglobulin
(MIg)-Associated Renal Diseases
• The triggering hematologic disease may be a malignant condition such
as MM or B cell lymphoproliferative disorder, or a non/pre-malignant
disorder such as MGRS
• Patients may present with acute renal failure, rapidly progressive
glomerulonephritis, nephritic or nephrotic syndrome, or slowly
progressive renal failure depending on the type and severity of the MIg-
associated renal disease
• The underlying pathology is variable and dictates the disease type
• In a small number of cases, the kidney biopsy may demonstrate the MIg,
yet the MIg is not detected in blood or urine and there is no evidence of
a plasma cell or B-cell lymphoproliferative disorder by current standard
testing techniques
The Complexity and Heterogeneity of Monoclonal
Immunoglobulin (MIg)-Associated Renal Diseases
• Most of the diseases are due to tissue deposition of the MIg
deposition (direct mechanism) while in others the MIg does not
deposit but causes injury via other mechanisms such as
dysregulation of the alternative pathway of complement deposition
(indirect mechanism)
• In some diseases the MIg is the sole etiology (as for cast
nephropathy, MIDD) whereas in others it is one of many possible
etiologies (as for C3 glomerulopathy)
• Finally treatment and prognosis vary depending on the type of renal
disorder and the underlying hematologic condition.
Summary
• Close interaction between the nephrologist,
pathologist and hematologist-oncologist is
essential for diagnosis and management of MIg
associated- renal disease
• MIG in the setting of kidney transplant- even
more important, recurrent disease
(next time)
New techniques detection of MIg
• Laser microdissection and mass
spectrometry
• Immunofluorescence studies following • Immunofluorescence studies following
pronase digestion of paraffin embedded
material
Laser micro dissection and mass spectrometry
Microdissection
Trypsin
digestion
Tandem MS/MSHPLC ESI Tandem MS/MSHPLC ESI
Data analysis
Diagnosis and typing of amyloidosis
Diagnostic Criteria
-Apolipoprotein E
-Serum amyloid P component
-Amyloidogenic protein
Patient x
• Mr. JS is a 77-year-old man of Eastern European descent presented with proteinuria
and severe renal insufficiency 6 months ago.
• The patient had numerous co-morbidities which included chronic obstructive
pulmonary disease, bronchiectasis, coronary artery disease, mild aortic stenosis,
arterial hypertension and dyslipidemia.
• Serum creatinine level was 2.2 mg/dL (194 µmol/L) with an estimated glomerular
filtration rate of 29 mL/min.
• Further evaluation showed nephrotic range proteinuria of 5.3 g/day. Microscopic
examination of the urine revealed greater than 100 red blood cells/high power field
• SPEP showed no M-spike on initial evaluation.
• However, the serum IFE revealed a monoclonal lambda band.
• Serum lambda free light chain level was elevated at 2303 mg/L with a kappa/lambda ratio of 0.02. A 24-hour urine collection revealed the presence of a monoclonal lambda light chain.
• Bone studies did not demonstrate any lytic bone lesion.
• A bone marrow biopsy was performed showing a normal cellularity, with a mild monoclonal plasmacytosis (5%)= MGUS, and a negative Congo red stain.
Based on LM and IF- what is your diagnosis so far?
Diagnosis: MIDD?
Kidney biopsy diagnosis: IgD heavy chain deposition disease.
IgD stain- immunoperoxidase
Control diabetic nodule Bone marrow
Immunofluorescence studies
following pronase digestion of
paraffin embedded material
Patient Y• A 67-year-old Caucasian woman status post living-
related kidney transplant was referred September 2015 to Mayo Clinic for evaluation of declining kidney allograft function.
• The patient had initially presented in September 2000 with a creatinine of 2 mg/dl and proteinuria of 1.3 with a creatinine of 2 mg/dl and proteinuria of 1.3 g/24h.
• A kidney biopsy showed mild arterial sclerosis, mild focal global glomerulosclerosis, and mild tubular atrophy and interstitial fibrosis associated with arterial sclerosis
• Serum complement levels were normal, and anti-neutrophil cytoplasmic antibodies, anti-nuclear antibody, and hepatitis B and C serologies were negative.
• At the time a monoclonal kappa light chain was detected in the urine on immunofixation studies. Additional past medical history included hypertension, hyperlipidemia, obstructive sleep apnea and nicotine dependence.
• No bone marrow biopsy was performed and she was considered to MGUS and was treated conservatively.considered to MGUS and was treated conservatively.
• Periodic evaluations of the monoclonal gammopathy showed no progression of her MGUS. In November 2012, the serum creatinine was 3.2 mg/dl
lambda IF following pronase digestion
kappa
lambda
kappa
Diagnosis
• De novo light chain proximal
tubulopathy in an allograft kidney
• Laboratory evaluation of kappa free light chains (FLC) in the serum showed elevated values between 50-60 mg/dl (normal range 0.33-1.94) and lambda FLC were normal.
• A bone marrow biopsy after the allograft kidney biopsy showed features of multiple myeloma with 5-10% of plasma cells that were positive for monotypic kappa light chains. monotypic kappa light chains.
• Congo red stain was negative. Imaging studies did not show any evidence of lytic lesions.
• She received four cycles of bortezomib and dexamethasone resulting in decline of kappa FLC to 3.8 mg/dl, consistent with a very good partial response. Since then, kappa light chains level have remained stable.
• The kidney function also improved with sCr decreasing progressively to 1.2 mg/dL, which are consistent with her baseline values.
• At the last follow-up, her kidney function remained stable (sCr 1.2 mg/dl, clearance 40 ml/min) and kappa FLC were 6.4 mg/dl.
Old native biopsy from 2000
lambda
kappa
Diagnosis: Light chain proximal tubulopathy,
recurrent
Light chain proximal tubulopathy
kappalambda
Light chain proximal tubulopathy• LCPT is characterized by cytoplasmic inclusions of monoclonal light chains
(more commonly kappa than lambda) within proximal tubular cells
• The inclusions can be crystalline (more common) or non-crystalline
• Kappa light chains of the Vk1 subgroup are the most pathogenic because
they introduce hydrophobic side chains on the variable domain that inhibit
proteolysis and facilitate crystallizationproteolysis and facilitate crystallization
• The non-crystalline LCPT is still poorly defined and requires differentiation
from physiologic tubular reabsorption: A helpful diagnostic feature of both
crystalline and non-crystalline LCPT is the presence of acute tubular injury
• Pronase IF technique very helpful
• LCPT was associated with a MGRS in 46% (of which 4% converted to MM),
MM in 33%, SMM in 15%, non-Hodgkin’s lymphoma in 4% and CLL in 2%
of the patients
Thank you