Lupus Nephritis Flashcards

1
Q

Lupus Nephritis

Epidemiology

A

Epidemiology

It is estimated that 60% of patients with SLE will develop clinically significant LN in the course of the disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Lupus Nephritis

Epidemiology

A

Age:

The majority of patients who develop LN are younger than 55 years old.

Severe nephritis is more common in children than elderly patients.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Lupus Nephritis

Epidemiology

A

Gender difference (female-to-male ratio) is noted for female predominance and varies with age:

2: 1 in prepubertal children
4: 1 in adolescents

8 to 12:1 in adults

2:1 in adults age greater than 60

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Lupus Nephritis

Epidemiology

A

Renal outcome portends worse prognosis in males than females.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Lupus Nephritis

Epidemiology

A

Race-related demographics:

SLE is more common in African Americans and Hispanics than whites.

Severe LN is more common in African Americans and Asians than in other ethnic groups.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Lupus Nephritis

Pathogenesis
Production of autoantibodies by mature B cells (plasma cells) against nuclear antigens (e.g., double stranded DNA (dsDNA), ribonucleoproteins, complement factors (e.g., C1q). This process may be driven by:

A

Antigenic mimicry: antibodies against bacterial or viral peptides cross-react to self-antigens.

Impaired clearance of apoptotic bodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Lupus Nephritis

Pathogenesis
Production of autoantibodies by mature B cells (plasma cells) against nuclear antigens (e.g., double stranded DNA (dsDNA), ribonucleoproteins, complement factors (e.g., C1q). This process may be driven by:

A

Polyclonal hyperactivity of the B-cell system or defects of T-cell autoregulation leading to high antibody production

Anti-double stranded DNA (anti-dsDNA) antibody response driven by histone-specific T-helper cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Lupus Nephritis

Pathogenesis:

A

IC deposition: deposition of circulating IC in GBM or direct binding of nucleosomal antigens to GBM followed by in situ autoantibody-binding activates both complement-dependent and independent inflammatory cascades.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Lupus Nephritis

IC clearance:

A

ICs are normally cleared by the C1 complement complex. Binding of C1 complex to IC leads to downstream complement activation and opsonization of the IC for phagocytosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Lupus Nephritis

IC clearance:

A

C1q is a component of the C1 complex. Upon binding of C1 complex to IC, C1 complex undergoes conformational change, exposing antigenic sites of C1q, which then leads to autoantibody formation against C1q. High autoantibody titers against C1q have been suggested to correlate with active lupus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Neutrophils:

A

Neutrophils:

NETosis: a process whereby upon exposure to microorganisms, neutrophils release nuclear components, granule proteins, and chromatin to form an extracellular matrix (ECM), referred to as “neutrophil extracellular traps” (NETs) to “trap,” destroy, and clear the invading microorganisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Neutrophils:

A

Neutrophils:

NETs comprise of DNA and histones along with various peptides and proteinases such as high-mobility group protein box-1, cathelicidin, myeloperoxidase, neutrophil elastase, matrix metalloproteinase 9, and proteoglycan recognition protein short.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Neutrophils:

A

Neutrophils:

NETs may serve as a source of autoantigens in SLE. There are data to suggest that NETs are complement activators and can play a role in increasing C1q deposition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Basophils:

A

Basophils:

Cross-linking of IgE to its receptors (FcκRI) on basophil surface leads to the secretion of histamine and proinflammatory cytokines by basophils.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Basophils:

A

There are data to suggest that increased titers of both dsDNA-IgE and dsDNA-IgG predict SLE disease activity better than dsDNA-IgG titers alone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Basophils:

A

Activated basophils secrete cytokines (IL-4 and IL-6) and express the MHC-II and B cell-activating factor BAFF (also known as B-Lys), which can enhance plasma cell survival and autoantibody production amplification loop.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Basophils:

A

Other functions of activated basophils: promotion and regulation of TH2 adaptive immune responses, antigen presentation to T cells, plasma cell differentiation and support, monocyte polarization and recruitment, and inflammatory site organization.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Macrophages/monocytes:

A

Macrophages/monocytes:

NETs containing LL37 stimulate NLRP3 inflammasome in monocytes and result in IL-1β and IL-18 release, NETosis, and amplification of the proinflammatory state.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

Macrophages/monocytes:

A

Macrophages/monocytes:

Polymorphism in the IL-18 gene promoter with associated increased IL-18 production may promote SLE susceptibility.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lupus Nephritis

Inflammatory effects following impaired apoptotic bodies clearance and/or IC formations and roles of other inflammatory cells:

A

Autoreactive B-cells and T-cells due to defective regulatory mechanisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Lupus Nephritis:

Advances in SLE targeted therapy:

A

Advances in SLE targeted therapy:

Belimumab: human monoclonal antibody that selectively neutralizes B-cell activating factor (BAFF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Lupus Nephritis:

Advances in SLE targeted therapy:

A

FDA approved for treatment of ANA/anti-dsDNA positive adults with high disease activity despite standard therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Lupus Nephritis:

Advances in SLE targeted therapy:

A

Short-term clinical trials suggest reduced SLE activity, flare rates, and corticosteroid need

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Lupus Nephritis:

Advances in SLE targeted therapy:

A

Sifalimumab: human monoclonal antibody that inhibits several IFN-α subtypes1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Lupus Nephritis:

Advances in SLE targeted therapy:

A

Rontalizumab: humanized mouse monoclonal anti-IFN-α-antibody.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Lupus Nephritis:

Advances in SLE targeted therapy:

A

Omalizumab: recombinant humanized monoclonal antibody that blocks the binding of IgE to the FcεRI receptor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Lupus Nephritis:

Diagnosis:

A

Routine laboratory findings:

Microscopic hematuria ± red blood cell casts, proteinuria ± nephrotic syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Lupus Nephritis:

Diagnosis:

A

Routine laboratory findings cont’d:

Serologies: positive antinuclear antibody (sensitive, not specific), anti-Smith (specific), anti-dsDNA, hypocomplementemia (particularly low C3). Anti-Smith is specific for the diagnosis of SLE. Anti-dsDNA and hypocomplementemia correlate with kidney disease activity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Lupus Nephritis:

Histopathology: International Society of Nephrology/Renal Pathology Society classification of LN:

A

Class I:

Minimal mesangial LN: normal glomeruli by LM; mesangial immune deposits by IF alone or by both IF and EM.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Lupus Nephritis:

Histopathology: International Society of Nephrology/Renal Pathology Society classification of LN:

A

Class II:

Mesangial proliferative LN: mesangial hypercellularity and matrix expansion on LM; mesangial immune deposits by both IF and EM.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Lupus Nephritis:

Histopathology: International Society of Nephrology/Renal Pathology Society classification of LN:

A

Class III: focal LN (<50% of glomeruli are involved)

Class III(A): Active lesions (leukocytes, karyhorrexis, cellular or fibrocellular crescents, large subendothelial deposits forming “wire loops” or “hyaline thrombi”)

Class III(A/C): Active and chronic lesions

Class III(C): Chronic lesions (segmental or global glomerulosclerosis, fibrotic crescents)

32
Q

Lupus Nephritis:

Histopathology: International Society of Nephrology/Renal Pathology Society classification of LN:

A

Class IV: Diffuse LN (≥50% glomeruli)

Diffuse segmental (IV-S) or global (IV-G)

Class IV(A): Active lesions

Class IV(A/C): Active and chronic lesions

Class IV(C): Chronic lesions

33
Q

Lupus Nephritis:

Histopathology: International Society of Nephrology/Renal Pathology Society classification of LN:

A

Class V:

Membranous LN (>50% subepithelial deposits with or without mesangial hypercellularity)

34
Q

Lupus Nephritis:

Histopathology: International Society of Nephrology/Renal Pathology Society classification of LN:

A

Class VI:

Advanced sclerosing LN (≥90% globally sclerosed glomeruli without residual activity)

35
Q

Lupus Nephritis:

Management:

A

Class I LN:

Benign, no long-term adverse effect on kidney function

Disease-specific therapy not necessary. Routine chronic kidney disease (CKD) progression risk reduction management.

36
Q

Lupus Nephritis:

Management:

A

Class II LN:

<1 g/d proteinuria: routine CKD progression risk reduction management and management of extrarenal manifestations of SLE as needed.

> 3 g/d proteinuria: Treatment with corticosteroids or calcineurin inhibitors (CNIs) as described for MCD/FSGS is suggested.

37
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

A

Class III and class IV LN initial induction therapy:

Initial therapy with corticosteroids plus either CYC or MMF.

38
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

A

Corticosteroids: oral prednisone 1 mg/kg, taper over 6 to 12 months per clinical response. Initial IV methylprednisolone (e.g., 5 to 10 mg/kg × 3 days may be considered at induction for aggressive disease—NOTE: dosing and duration have not been tested in any randomized controlled trials [RCTs]).

39
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC

A

CYC

Intravenous cyclophosphamide (IV CYC):

“NIH regimen”: (0.5 to 1.0 g/m2) given monthly for 6 months

Euro-Lupus regimen: (500 mg) given every 2 weeks for 3 months (equivalent efficacy as NIH regimen in Caucasians).

40
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC

A

Euro-Lupus study was limited to less severe patients (severe disease was defined as >50% segmental glomerular necrosis or crescents and rapidly progressive kidney failure).

Whether efficacy of Euro-Lupus is similar to that of NIH regimen in class III/IV or in non-Caucasians is not known.

41
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC

A

Oral cyclophosphamide (PO CYC): 1.0 to 1.5 mg/kg/d (maximum dose 150 mg/d) for 2 to 4 months.

Similar efficacy to IV CYC in prospective observational studies.

Some but not all investigators suggested more adverse effects with PO CYC compared with IV CYC.

42
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC

A

Safety notes for use of CYC:

Maximum lifetime dose of 36 g of CYC is suggested to minimize risk of hematologic malignancies.

43
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC

A

Dose reduction with renal insufficiency (20% and 30% reduction for CrCl 25 to 50 and 10 to 25 mL/min, respectively

Adjust CYC dose to keep nadir leukocyte count ≥ 3,000/μL (typically occurs in 10 to 14 days for IV CYC and 1 week for PO CYC)

Use sodium-2-mercaptoethane (mesna) to minimize bladder toxicity

44
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC

A

Fertility protection while on CYC treatment:

Women: leuprolide, ovarian tissue cryopreservation

Men: testosterone (efficacy poorly established), sperm banking

45
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

MMF

A

MMF: 750 to 1,500 mg twice daily for 6 months

MMF was shown to have similar efficacy as PO CYC in Chinese population; severe LN were excluded.

46
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

MMF

A

Aspreva Lupus Management Study (ALMS), RCT involving patients with class III, IV, and V LN: MMF had an equivalent response rate for induction compared with IV CYC at 6 months, with similar incidence of adverse events including serious infections and deaths.

47
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

MMF

A

Post hoc analysis of ALMS indicated inferior outcomes with CYC compared to MMF in black, Hispanic, and mixed-race patients (patients considered to have more resistant LN).

48
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC versus MMF for induction therapy:

A

If disease worsens as evidenced by increasing SCr or proteinuria during the first 3 months of therapy with either CYC or MMF, switch therapy (e.g., from CYC to MMF or vice versa) or use alternative therapy (see options below). Consider rebiopsy.

49
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC versus MMF for induction therapy:

A

Definitions of response:

Complete response: return of SCr to baseline, plus a decline in urine protein to creatinine ratio (uPCR) < 500 mg/g

Partial response: stabilization (±25%) or improvement of SCr plus ≥ 50% decrease in uPCR where final uPCR is <3,000 mg/g

50
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC versus MMF for induction therapy:

A

Response rates appear equivalent, but current data suggest a trend for more relapses, prolonged proteinuria > 1 g/d, and persistent SCr > 2 mg/dL in MMF compared to CYC induction therapy.

51
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

CYC versus MMF for induction therapy:

A

CYC RCTs included patients with more severe LN compared to MMF trial. CYC may thus be preferred over MMF in patients with severe LN.

52
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Other alternative therapies:

A

AZA: AZA + corticosteroids had similar induction response rate compared with that for IV CYC + corticosteroids at 2 years. AZA had fewer adverse effects, but had higher late relapse rate, risk of doubling of SCr, and more chronic changes on late follow-up biopsies.

53
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Other alternative therapies:

A

Cyclosporine (CSA): 4 to 5 mg/kg/d

Comparable remissions to IV CYC

Nephrotoxicity limits use in patients with elevated SCr.

54
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Other alternative therapies:

A

Tacrolimus (TAC): comparable remission rates between combination TAC (4 mg/d) + MMF (1 g/d) + glucocorticoids and IV CYC (0.75 g/m2) for 6 months (Chinese RCT).

55
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Other alternative therapies:

A

Adding rituximab to standard MMF + corticosteroids for induction therapy provided no added benefit and is not recommended.

56
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Class III and IV LN maintenance therapy:

A

Either AZA (1.5 to 2.5 mg/kg/d) or MMF (1 to 2 g/d in divided doses) and low-dose oral corticosteroids (≤10 mg/d prednisone equivalent) is recommended.

57
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Class III and IV LN maintenance therapy:

A

With the exception of the ALMS trial where MMF is a better maintenance agent compared to AZA in composite treatment failure endpoint (death, ESRD, kidney failure, sustained doubling of SCr, or requirement for rescue therapy), AZA and MMF generally have comparable maintenance efficacy.

58
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Class III and IV LN maintenance therapy:

A

Maintenance therapy with AZA or MMF has been suggested to be superior to CYC based on risk of death and development of CKD.

59
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Class III and IV LN maintenance therapy:

A

Use of CNIs is suggested for patients who cannot tolerate MMF or AZA.

Duration of maintenance is not known, but suggested to be at least 1 year. Average duration of immunosuppressive therapy from 7 RCTs was 3.5 years.

60
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Class III and IV LN maintenance therapy:

A

If disease relapses during tapering period, go back to previous level of immunosuppression that controlled disease.

61
Q

Lupus Nephritis:

Management:

Class III and class IV LN initial induction therapy:

Monitoring of LN:

A

Serial proteinuria and SCr

Hematuria may persist for months even with improved proteinuria and SCr.

Complement levels (up to 80% sensitivity) and anti-double-stranded DNA antibodies (up to 70% to 80%)

62
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Measurable SLE disease activity is present in 40% to 50% of pregnancies, with LN occurring in up to 75% of these cases.

Active SLE during pregnancy is associated with:

Increased risk of preeclampsia to 30% compared to 5% in the general population

Increased risk of fetal death and preterm birth

63
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Active LN during pregnancy is associated with:

Increased maternal adverse outcomes including increased risk of gestational HTN, preeclampsia, and maternal death. There is evidence to suggest that LN classes III and IV may be associated with greater risk for hypertension/preeclampsia compared to other LN classes.

Likely increased risks of preterm birth, intrauterine growth restriction, stillbirth, and neonatal death. (Inconsistent findings in the literature.)

64
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Risk factors for adverse outcomes in pregnancy:

Active disease at conception

Antiphospholipid antibodies

HTN, proteinuria, reduced GFR in the first trimester

Chronicity of disease

65
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Management of antiphospholipid syndrome (APS)/nephrotic syndrome during pregnancy:

Adverse outcomes of APS and positive antiphospholipid antibodies: late fetal loss (after 10 weeks of gestation), increased relative risk of preeclampsia

Women with APS and arterial thrombotic events are also at high risks for stroke and maternal morbidity and mortality.

Routine screening for antiphospholipid antibodies is recommended.

66
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Anticoagulation:

For women with known APS receiving chronic anticoagulation: convert warfarin to unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) during pregnancy.

67
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Anticoagulation cont’d:

For women with no known history of thrombotic events, but with obstetric criteria for APS of having either ≥3 pregnancy losses or late pregnancy loss, prophylactic anticoagulation consisting of a low dose aspirin with either UFH or LMWH should be initiated

68
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Anticoagulation cont’d:

For women with antiphospholipid antibodies but not meeting clinical criteria for APS, clinical surveillance with either antepartum aspirin or prophylactic UFH or LMWH is suggested.

For patients with nephrotic syndrome, prophylactic anticoagulation should be considered.

69
Q

Lupus Nephritis:

Lupus and Pregnancy

A

Differentiating between lupus flare and preeclampsia in a woman with AKI:

Lupus flare: AKI may occur any time including prior to 20 weeks of gestation and postpartum, presence of hypocomplementemia, red blood cell casts, and leukopenia

Preeclampsia: AKI only occurs after 20 weeks of gestation with absence of findings seen with lupus flare above.

70
Q

Lupus Nephritis:

Lupus and Pregnancy

Management of SLE/LN in pregnancy per KDIGO 2012:

A

Management of SLE/LN in pregnancy per KDIGO 2012:

Delay pregnancy until complete remission

Use of CYC, MMF, ACEI, and ARB is not recommended due to potential teratogenicity.

71
Q

Lupus Nephritis:

Lupus and Pregnancy

Management of SLE/LN in pregnancy per KDIGO 2012:

A

Methotrexate is teratogenic and is contraindicated in pregnancy. Methotrexate should be discontinued ≥3 months prior to conception.

72
Q

Lupus Nephritis:

Lupus and Pregnancy

Management of SLE/LN in pregnancy per KDIGO 2012:

A

Hydroxychloroquine maintenance therapy should be continued during pregnancy. Discontinuation of hydroxychloroquine may lead to lupus flares including LN.

73
Q

Lupus Nephritis:

Lupus and Pregnancy

Management of SLE/LN in pregnancy per KDIGO 2012:

A

LN patients who become pregnant while being treated with MMF be switched to AZA.

74
Q

Lupus Nephritis:

Lupus and Pregnancy

Management of SLE/LN in pregnancy per KDIGO 2012:

A

Patients with LN relapse during pregnancy should be treated with corticosteroids, and if necessary, AZA.

75
Q

Lupus Nephritis:

Lupus and Pregnancy

Management of SLE/LN in pregnancy per KDIGO 2012:

A

Patients receiving corticosteroids or AZA during pregnancy should not be tapered until at least 3 months postpartum.

Administration of low-dose aspirin during pregnancy is suggested to reduce risk of fetal loss.