AVISE Interpretation Guide

Interpretation Guide

SLE Associated Markers

Marker (method) Associated Disease Sensitivity Interpretation

EC4d (FACS) Systemic Lupus

Erythematosus (SLE)

46%

Cell-Bound Complement Activation Products (CB-CAPs) EC4d & BC4d are measures of

classical complement activation. CB-CAPs are primarily associated with SLE with 66%

of patients having one or both CB-CAPs elevated

. EC4d signicantly correlates with

uctuations in SLE disease activity

BC4d (FACS) SLE prognostic 53%

C3 (IT) SLE 33%

C3/C4 proteins are integral components of the complement system. Abnormally low

concentrations of C3/C4 associate with SLE primarily with 44% of SLE patients having one

or both proteins abnormally low.

C4 (IT) SLE prognostic 32%

Anti-C1q IgG

(ELISA)

Lupus Nephritis/

disease activity

58%

Antibodies against the complement protein C1q are found in 58% of SLE patients with

active lupus nephritis. Anti-C1q levels associate with renal activity

. Low levels of anti-

C1q antibodies have been found in up to 8% of patients with other diseases, such as

infection and normal healthy individuals.

Anti-dsDNA IgG

(ELISA and IFA)

SLE 33%

Anti-dsDNA antibodies provide high positive predictive value due to high specicity for

SLE. In the AVISE Lupus algorithm, patients are initially screened with an ELISA assay, and

all patients testing positive are reexed to Crithidia luciliae IFA testing for conrmation.

Anti-dsDNA

(CIA)

SLE/disease activity 46%

24,25

The anti-dsDNA by CIA method measures quantitative levels of anti-double stranded

deoxyribonucleic acid with a superior correlation to disease activity compared to other

methods.

Anti-Nuclear

Antibodies IgG

(ANA)

(ELISA and IFA)

Autoimmune Diseases 89% in SLE

ANA has high negative predictive value for ruling out SLE due to its high sensitivity for

SLE. However, ANA is found in many autoimmune disorders and a signicant proportion

of apparently healthy individuals.

Anti-Ribosomal

P IgG

(ELISA)

Neuropsychiatric Lupus 9%

Antibodies against ribosomal-P are highly specic for SLE and can be present in anti-

dsDNA or anti-Sm negative patients. Anti-Ribosomal-P antibodies have been shown to

associate with neuropsychiatric SLE manifestations.

Anti-Smith IgG

(ELISA)

SLE 14%

Anti-Smith antibodies are highly specic, but comparatively low sensitivity marker for

SLE. One of the ACR criteria for SLE.

ENA Markers

Marker (method) Associated Disease Sensitivity Interpretation

Anti-CENP IgG

(ELISA)

CREST Syndrome 20-60%

Antibodies to (CENP) protein-B are found in 20-60% of patients with CREST syndrome, a

limited form of scleroderma.

Anti-Jo-1 IgG

(ELISA)

Polymyositis/

Dermatomyositis (PM/

DM)

20-30%

Marker to aid diagnosis of PM/DM. Found in about 25% of patients with PM/DM.

Anti-RNP70 IgG

(ELISA)

Mixed Connective

Tissue Disease (MCTD)

90%

RNP70 is a 70 kDa protein of the U1-snRNP complex. RNP70 antibodies are highly

sensitive for MCTD.

Anti-Scl-70 IgG

(ELISA)

Scleroderma 28-70%

Up to 70% of scleroderma patients are positive. Anti-Scl70 is highly specic for diffuse

cutaneous scleroderma and associates with interstitial lung disease (ILD).

Anti-Ro52 IgG

(CIA)

Myositis, SLE,

Sjögren’s Syndrome &

Scleroderma

20-70%

Ro52 antibodies are found in multiple autoimmune conditions. Anti-Ro52 has been

shown to associate with interstitial lung disease (ILD) in patients with Sjögren’s syndrome

or scleroderma.

Anti-Ro60 IgG

(CIA)

SLE, Sjögren’s

Syndrome, Myositis &

Scleroderma

20-65%

Ro60 antibodies are found in multiple autoimmune conditions. Anti-Ro60 is commonly

found in both SLE and Sjögren’s syndrome.

Anti-RNA PoI

III IgG

(ELISA)

Systemic Sclerosis 5-22%

Antibodies against RNA polymerase III are specic for systemic sclerosis often found in

the absence of anti-Scl70 and anti-CENP antibodies. RNA Pol III antibodies associate with

diffuse cutaneous scleroderma.

Anti-SS-B/La IgG

(ELISA)

Sjögren’s Syndrome 39%

Anti-La antibodies are a low sensitivity but highly specic marker for Sjögren’s Syndrome.

Anti-U1-RNP IgG

(ELISA)

MCTD 95-99%

Anti-U1-RNP antibodies are highly sensitive for MCTD. Absence of anti-U1-RNP antibodies

is used to rule out MCTD.

Anti-Histone IgG

(ELISA)

Drug-Induced Lupus

(DIL)

95%

Up to 95% of drug-induced lupus and 50% of SLE patients exhibit elevated levels of

histone antibodies. Histone antibodies have also been found in RA, DM, and SS placing

added importance on clinical presentation.

AVISE CTD

AVISE APS

AVISE Lupus

SLE Monitor

SLE Prognostic

AVISE Vasculitis

Marker (method) Associated Disease Sensitivity Interpretation

RA Markers

Anti-Cyclic

Citrullinated

Peptide IgG (ELISA)

Rheumatoid

Arthritis (RA)

70-90%

Antibodies to Cyclic Citrullinated Peptides (CCP) aid in the diagnosis of Rheumatoid

Arthritis (RA). Anti-CCP antibodies are highly specic for RA. Anti-CCP is included in the

AVISE Lupus algorithm to help with the differential diagnosis of RA vs. SLE.

Anti-Carbamylated

Protein IgG

(ELISA)

RA 33%

Anti-CarP antibodies serve as a marker of more severe prognosis in RA, independent of

anti-CCP or RF status. Studies have shown anti-CarP found in early RA associates with

future erosive damage. The clinical signicance of positive anti-CarP in the absence of

RA has not been established.

Rheumatoid Factor

IgM & IgA (ELISA)

RA 70-90%

Quantitative measurement of IgM and IgA rheumatoid factors (RF) to aid in the

diagnosis of rheumatoid arthritis. Presence of IgA RF isotype may be associated with

more severe RA prognosis.

APS Markers

Marker (method) Associated Disease Sensitivity Interpretation

Anti-β2-

Gylcoprotein

I IgG, IgM & IgA

(ELISA)

Antiphospholipid

Syndrome (APS)

45%

Antibodies to Beta 2 Glycoprotein 1 (ß 2 GP1) exhibit higher specicity than anti-

cardiolipin assays. In 3-10% of APS patients, ß2 GP1 antibodies may be the only

positive test. Positive results should be conrmed after 12 weeks to ensure persistency

of antibodies. IgA ß2 GP1 antibodies are less common than IgG or IgM and can occur

in isolation.

Anti-Cardiolipin

IgG, IgM & IgA

(ELISA)

APS 97%

Antibodies to cardiolipin are present in SLE patients (30-40%) and APS. Prevalence of

cardiolipin in APS is high but specicity for APS is lower than other anti-phospholipid

antibodies. Positive results should be conrmed after 12 weeks.

Anti-

Phosphatidylserine

/Prothrombin

(PS/PT) IgM & IgG

(ELISA)

APS 22-37%

Anti-PS/PT antibodies are markers for APS that have been found to signicantly

correlate with lupus anticoagulant (LAC)

. Unlike LAC, anti-PS/PT testing is unaffected

by anti-coagulant therapy.

Thyroid Markers

Marker (method) Associated Disease Sensitivity Interpretation

Anti-Thyroglobulin

IgG (ELISA)

Hashimoto’s Thyroiditis

& Graves’ Disease

60-85%

Anti-thyroglobulin antibodies are found in 60-85% of patients with Hashimoto’s

thyroiditis and 30-80% of patients with Graves’ disease.

Anti-Thyroid

Peroxidase IgG

(ELISA)

Hashimoto’s Thyroiditis

& Graves’ Disease

71-97%

Anti-thyroid peroxidase antibodies are found in > 90% of patients with Hashimoto’s

thyroiditis & 71-97% of patients with Graves’ disease. Over 95% of thyroiditis patients

have Thyroglobulin IgG and/or Thyroid peroxidase antibodies.

Vasculitis Markers

Marker (method) Associated Disease Sensitivity Interpretation

ANCA

(IFA)

ANCA associated

vasculitis

77%

The c-ANCA pattern produces a granular cytoplasmic pattern with interlobular

accentuation on ethanol xed neutrophils. c-ANCA patterns are associated with

necrotizing segmental glomerulonephritis and GPA

19, 20

85%

The p-ANCA pattern produces perinuclear staining with or without nuclear extension.

The p-ANCA pattern is commonly detected in patients with MPA and about 40% of

patients with EGPA

20, 24

Anti-PR3 IgG

(CIA)

Granulomatosis with

Polyangiitis (GPA)

81%

Anti-PR3 antibodies are primarily associated with GPA and to a lesser extent, found in

MPA (10%) and EGPA

18, 19

. However, anti-PR3 antibodies can also be seen in connective

tissue disease, IBD, some infections, malignancy, and as a reaction to drugs. Therefore,

results should be interpreted with care in light of the clinical ndings and workup

Anti-MPO IgG

(CIA)

Microscopic

Polyangiitis (MPA)

85%

Anti-MPO antibodies are primarily associated with MPA and to a lesser extent, found in

GPA (6%) and EGPA

18,19

. However, anti-MPO antibodies can also be seen in connective

tissue disease, IBD, some infections, malignancy, and as a reaction to drugs. Therefore,

results should be interpreted with care in light of the clinical ndings and workup

Anti-GBM IgG

(CIA)

Goodpasture’s

Syndrome (GPS)

96%

Anti-GBM antibodies are often associated with Goodpasture’s disease and anti-GBM

nephritis

. A signicant proportion of patients with anti-GBM disease are also positive

for ANCA.

AVISE Interpretation Guide

AVISE CTD

AVISE APS

AVISE Lupus

SLE Monitor

SLE Prognostic

AVISE Vasculitis

AVISE HCQ

A test to aid in assessing adherence to HCQ and individual exposure

to HCQ as measured in whole blood.

HCQ Level Interpretation & Consideration

Therapeutic (>1000 ng/mL) Level associated with clinical efcacy.

HCQ is likely absorbed effectively.

Sub-therapeutic (200-1000 ng/mL) Patient could be partially adherent to therapy.

Patients with HCQ lower than 1000 ng/mL can

be at greater risk for disease are.

Underexposed (<200 ng/mI) Patient is likely non-adherent to HCQ therapy.

AVISE MTX

A test to aid in assessing adherence to MTX and individual exposure to

active MTX metabolites in red blood cells.

MTXPG Level Interpretation & Consideration

Therapeutic (>60 nmol/L) Patient is metabolizing MTX effectively.

Level is consistent with clinical efcacy.

Intermediate (20-60 nmol/L) Patient may need more exposure to MTX.

Sub-therapeutic (<20 nmol/L) Patient may not be metabolizing MTX effectively

or patient may be non-adherent with therapy.

AVISE Interpretation Guide

FACS: Fluorescence-Activated Cell Sorting

IFA: Immunouorescence

Methodology Denitions:

ELISA: Enzyme -Linked Immunosorbent Assay

CIA: Chemiluminescent Immunoassay

IT: Immunoturbidimetry

A deeper look at the AVISE® Lupus two tier algorithm

Tier 1 criteria is highly specic for SLE

TIER 1

TIER 2

Any of the Following:

Anti-Sm >10 U/mL

EC4d >75 Net MFI

BC4d >200 Net MFI

Anti-dsDNA ≥ 302 U/ML

If Tier 1 is Negative move to Tier 2

When levels are elevated Impact on Index

(Positive anti-dsDNA ELISA Conrmed

by Crithidia)

Negative

Positive

ANA Component

ELISA

CB-CAPs Component

EC4d & BC4d

Specicity Component

Anti-CCP

Anti-SS-B/La

Anti-CENP

Anti-Scl-70

Anti-Jo-1

< -0.1 Index Value >0.1

Tier 2 generates an index value based on the following components

• Level of ANA ELISA result (negative, positive, strong positive)

• Measurement of classical complement activation (CB-CAPs component) measured on a continuous scale

• Presence of auto-antibodies specic to other autoimmune CTDs

AVISE Interpretation Guide

Order ID

Identifier Received

Created

Collected

Provider

Susan S.

739814

Exagen Provider MD

12/22/2022

541163

Exagen ID

12/23/2022

PatientSpecimen

Received

Test Order

Reported

Female - 01/01/1996

Gender - DOB

Sample,

12/23/2022

12/28/2022

Approved by:

Results were obtained using flow cytometry for complement C4d fragment bound to erythrocytes (EC4d) and B-lymphocytes (BC4d). Autoantibodies were determined using

solid phase immunoassays. ANA was determined by indirect immunofluorescence and solid phase assays. ANA by solid phase assay was used for the index calculation. In a

study of 794 subjects comprising 304 SLE patients, 285 patients with other rheumatic diseases and 205 normal healthy controls, positivity for Tier 1 markers (anti-dsDNA,

confirmed using Crithidia, anti-Sm or elevated EC4d and BC4d) was associated with a sensitivity of 46% and a specificity of 97%. Among the 440 subjects negative in Tier 1, a

positive index score composite of ANA (by ELISA), EC4d/BC4d and positivity for anti-citrullinated peptide antibodies, SS-B/La, CENP, Jo-1 or Scl-70 resulted in sensitivity of

62% for SLE and specificity of 89%. Two tier combination yielded 80% sensitivity for SLE and 86% specificity for other rheumatic diseases (98% specificity vs. healthy).

Tier 1 Analytes

Tier 2 Analytes

AVISE Lupus Result:

Negative PositiveIndeterminate

12Page of

AVISE CTD Test Report

Tier 1

Positive

CB-CAP: EC4d - Erythrocyte-bound C4d

CB-CAP: BC4d - B-lymphocyte-bound C4d

<61 - Negative | 61-200 - Positive | >200 - Strong Positive

<15 - Negative | 15 -75 - Positive | >75 - Strong Positive

Net MFI

Anti-dsDNA IgG

<201 - Negative | 201-<302 - Equivocal |≥302 - Positive

IU/mL

Anti-Smith IgG

<7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

ANA IgG

<20 - Negative | 20-<60 - Positive | ≥60 - Strong Positive

Units

Anti-SS-B/La IgG

<7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Anti-Scl-70 IgG

<7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Anti-Centromere Protein B (CENP) IgG

<7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Anti-Jo-1 IgG

<7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Anti-CCP IgG U/mL

<7 - Negative | 7-10 - Equivocal | >10 - Positive

Tier 1

Assessment

<61 - Negative | 61-200 - Positive | >200 - Strong Positive

<15 - Negative | 15-75 - Positive | >75 - Strong Positive

Net MFI

Tier 2

Assessment

Value Interpretation Reference Range

Confirmation by Crithidia luciliae

Note:

CB-CAP: EC4d - Erythrocyte-bound C4d

CB-CAP: BC4d - B-lymphocyte-bound C4d

The Tier 1 result is associated with an increased likelihood of SLE and is the product of the following analyte values meeting the Tier 1

criteria: Anti-dsDNA, confirmed by Crithidia IFA

Tier 1 Positive

413.00 POSITIVE

Negative

POSITIVE

1.0

125

Positive

Not

assessed

due to

Tier 1

Positive

125

Negative

POSITIVE

1.0

STRONG POSITIVE>150

Negative

Positive anti-dsDNA confirmed by Crithidia

Date:Richard Safrin, MD 12-28-2022

AVISE® CTD and AVISE Lupus result report

Analytes included in Tier 1

and Tier 2 along with respective

assessments are reported in

two distinct sections

The result for the AVISE Lupus algorithm is

featured rst, plotted along a gradient of

increasing likelihood for presence of SLE

AVISE Interpretation Guide

Order ID

Identifier Received

Created

Collected

Provider

Susan S.

Exagen Provider MD

739814

12/22/2022

541163

Exagen ID

12/23/2022

PatientSpecimen

Received

Test Order

Reported

Female - 01/01/1996

Gender - DOB

Sample,

12/23/2022

12/28/2022

Value Interpretation

SLE-Associated Analytes

ANA IgG Units

ELISA: <20 - Negative | 20-<60 - Positive | ≥60 - Strong Positive

ANA by HEp-2

IFA: <1:80 - Negative | ≥1:80 - Positive

Titer:

Cytoplasmic Pattern:

CB-CAP: EC4d - Erythrocyte-bound C4d Net MFI

FACS: <15 - Negative | 15-75 - Positive | >75 - Strong Positive

CB-CAP: BC4d - B-lymphocyte-bound C4d Net MFI

FACS: <61 - Negative | 61-200 - Positive | >200 - Strong Positive

Other Autoimmune Disease Auto-Antibodies

Anti-dsDNA IgG

ELISA: <201 - Negative | 201-<302 - Equivocal |≥302 - Positive

IU/mL

Anti-Smith IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-U1RNP IgG

ELFA: <5 - Negative | 5-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-RNP70 IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Ro52 IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Anti-SS-B/La IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Scl-70 IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Centromere Protein B (CENP) IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Jo-1 IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Rheumatoid Factor IgM IU/mL

ELFA: <3.5 - Negative | 3.5-5 - Equivocal | >5 - Positive

Rheumatoid Factor IgA

ELFA: <14 - Negative | 14-20 - Equivocal | >20 - Positive

IU/mL

Negative

Anti-CCP IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Ro60 IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Cardiolipin IgM U/mL

Negative ELFA: <10 - Negative | 10-40 - Weak Positive | >40 - Positive

Anti-Cardiolipin IgG

ELFA: <10 - Negative | 10-40 - Weak Positive | >40 - Positive

U/mL

Negative

Anti-β2 Glycoprotein 1 IgM

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-β2 Glycoprotein 1 IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

Anti-Thyroglobulin IgG IU/mL

Negative ELFA: <40 - Negative | 40-60 - Equivocal | >60 - Positive

Anti-Thyroid Peroxidase IgG

ELFA: <25 - Negative | 25-35 - Equivocal | >35 - Positive

IU/mL

Negative

Notes:

22Page of

References

Confirmation by Crithidia luciliae

IFA: Negative

Reference Range

Value Interpretation Reference Range

Nuclear Pattern:

>150 STRONG POSITIVE

Negative

1:320

Homogeneous

Observed

413.00

1.0

125

3.0

1.0

5.0

1.0

2.0

1.0

3.0

2.0

4.0

3.0

2.0

<12

POSITIVE

Rheumatoid Arthritis Auto-Antibodies

Antiphospholipid Syndrome Auto-Antibodies

Thyroid Auto-Antibodies

POSITIVE

1) Kalunian K, et al. Measurement of CB-CAPs enhances diagnostic performance in SLE. Arthritis Rheum. 2012 Dec;64(12):4040-7. 2) Wallace D, et al. Systemic lupus erythematosus and primary

fibromyalgia can be distinguished by testing for cell-bound complement activation products. Lupus Sci Med., 2016 Feb;3(1):e000127. 3) Putterman C, et al. CB-CAPS in SLE: comparison with anti-ds DNA

and standard complement measurements. Lupus Sci Med. 2014 Oct;1(1):e000056

Anti-RNA Pol III IgG

ELFA: <7 - Negative | 7-10 - Equivocal | >10 - Positive

U/mL

Negative

10.0

1261 Liberty Way, Vista CA 92081

CLIA# 05D1075048

CAP# 7201051 | NYSDOH PFI# 8369

Laboratory Directors:

Richard Safrin, MD

R. Harper Summers, MD

Provider Relations: 888.452.1522

AVISE® tests are used for clinical purposes, not to be regarded as investigational or for research. Results are not intended to be used as the sole means for clinical diagnosis and patient

management decisions. This test (AVISE CTD) was developed, and performance characteristics were determined by Exagen Inc. as a Laboratory Developed Test (LDT). The Exagen

laboratory is certified under the Clinical Laboratory Amendments of 1988 (CLIA) and accredited by the College of American Pathologists (CAP) as qualified to perform high-complexity

clinical laboratory testing, and FDA approval or clearance is not necessary.

AVISE and the AVISE and Exagen logos are registered trademarks of

SA1267 (12/22)

AVISE® CTD and AVISE Lupus page 2

Details for ANA (HEp-2) are at the top of the page including any observed nuclear and cytoplasmic patterns

Far left column identies

positive(+) and strong

positive(++) interpretations

for each analyte

Notes provide clarication

and summary statements

Provider Relations: 888.452.1522

Call Provider Relations with any

questions or to arrange for a

clinical consultation

AVISE Interpretation Guide

References:

1. Putterman C, Furie R, Ramsey-Goldman R, et al. Cell-bound complement activation products in systemic lupus erythematosus: comparison with anti-double-stranded DNA and standard

complement measurements. Lupus Sci Med. 2014;1(1):e000056. doi:10.1136/lupus-2014-000056

2. Buyon J, Furie R, Putterman C, et al. Reduction in erythrocyte-bound complement activation products and titres of anti-C1q antibodies associate with clinical improvement in systemic

lupus erythematosus. Lupus Sci Med. 2016;3(1):1-8. doi:10.1136/lupus-2016-000165

3. Petri MA, Conklin J, O’Malley T, Dervieux T. Platelet-bound C4d , low C3 and lupus anticoagulant associate with thrombosis in SLE. Lupus Sci Med. Published online 2019:6-11. doi:10.1136/

lupus-2019-000318

4. Yin Y, Wu X, Shan G, Zhang X. Diagnostic value of serum anti-C1q antibodies in patients with lupus nephritis: A meta-analysis. Lupus. 2012;21(10):1088-1097.

doi:10.1177/0961203312451202

5. Hanly JG, Urowitz MB, Su L, Romero-Diaz J. Autoantibodies as biomarkers for the prediction of neuropsychiatric events in systemic lupus erythematosus Ann Rheum Dis. 2011;70(12):2240.

doi:10.1136/ard.2010.148502corr1

6. Russo K, Hoch S, Dima C, Varga J, Teodorescu M. Circulating anticentromere CENP-A and CENP-B antibodies in patients with diuse and limited systemic sclerosis, systemic lupus

erythematosus, and rheumatoid arthritis. J Rheumatol. 2000;27(1):142-148

7. Zampieri S, Ghirardello A, Iaccarino L, Tarricone E, Gambari PF, Doria A. Anti-Jo-1 antibodies. Autoimmunity. 2005;38(1):73-78. doi:10.1080/08916930400022640

8. Homan R.W., Greidinger E.L. (2002) Mixed Connective Tissue Disease. In: Tsokos G.C. (eds) Modern Therapeutics in Rheumatic Diseases. Humana Press, Totowa, NJ. Doi:10.1007/978-1-

59259-239-5_23

9. Basu D, Reveille JD. Anti-scl-70. Autoimmunity. 2005;38(1):65-72. doi:10.1080/08916930400022947

10. Robbins A, et al. Diagnostic Utility of Separate Anti-Ro60 and Anti-Ro52/TRIM21 Antibody Detection in Autoimmune Diseases. Front Immunol. 2019;10:444. doi: 10.3389/

mmun.2019.00444

11. Maes L, et al. Anti-PL/Scl-100 and RNA-Pol III antibodies in scleroderma. Clin Chim Acta. 2010; 411(13-14): 965-71. doi: 10.1016/j.cca.2010.03.018

12. Dalle Vedove C, Simon JC, Girolomoni G. Drug-induced lupus erythematosus with emphasis on skin manifestations and the role of anti-TNFα agents. J Dtsch Dermatol Ges.

2012;10(12):889-897. doi:10.1111/j.1610-0387.2012.08000.x

13. Rantapää-Dahlqvist S, de Jong BA, Berglin E, et al. Antibodies against cyclic citrullinated peptide and IgA rheumatoid factor predict the development of rheumatoid arthritis. Arthritis

Rheum. 2003;48(10):2741-2749. doi:10.1002/art.11223

14. Truchetet ME, et al. Association of the presence of anti-carbamylated protein antibodies in early arthritis with a poorer clinical and radiological outcome. Arthritis & Rheumatology.

2017;69(12): 2292-2302. doi: 10.1002/art.40237

15. Monica Galli, Davide Luciani, Guido Bertolini, Tiziano Barbui; Anti–β2-glycoprotein I, antiprothrombin antibodies, and the risk of thrombosis in the antiphospholipid syndrome. Blood.

2003; 102 (8): 2717–2723. doi: 10.1182/blood-2002-11-3334

16. Akhter E, Shums Z, Norman GL, Binder W, Fang H, Petri M. Utility of antiphosphatidylserine/prothrombin and IgA antiphospholipid assays in systemic lupus erythematosus. J Rheumatol.

2013;40(3):282-286. doi:10.3899/jrheum.120084

17. Engler H, Riesen WF, Keller B. Anti-thyroid peroxidase (anti-TPO) antibodies in thyroid diseases, non-thyroidal illness and controls. Clinical validity of a new commercial method for

detection of anti-TPO (thyroid microsomal) autoantibodies. Clin Chim Acta. 1994;225(2):123-136. doi:10.1016/0009-8981(94)90040-x

18. Mahler M, Radice A, Yang W, et al. Clinica Chimica Acta Development and performance evaluation of novel chemiluminescence assays for detection of anti-PR3 and anti-MPO antibodies.

Clin Chim Acta. 2012;413(7-8):719-726. doi:10.1016/j.cca.2012.01.004

19. Damoiseaux J, Csernok E, Rasmussen N, et al. Detection of antineutrophil cytoplasmic antibodies (ANCAs): A multicentre European Vasculitis Study Group (EUVAS) evaluation of the value

of indirect immunouorescence (IIF) versus antigen-specic immunoassays. Ann Rheum Dis. 2017;76(4):647-653. doi:10.1136/annrheumdis-2016-209507

20. Savige J, Gillis D, Benson E, et al. International Consensus Statement on Testing and Reporting of Antineutrophil Cytoplasmic Antibodies (ANCA). Am J Clin Pathol. 999;111(4):507-13. doi:

10.1093/ajcp/111.4.507

21. Wallace ZS, Miloslavsky EM. Management of ANCA associated vasculitis. BMJ. 2020;368(March):1-16. doi:10.1136/bmj.m421

22. Mahler M, Radice A, Sinico RA, et al. Performance evaluation of a novel chemiluminescence assay for detection of anti-GBM antibodies: an international multicenter study. 2012;3(May

2011):24

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