Cerebrospinal fluid (CSF) in the diagnosis of MS

Cerebrospinal fl uid (CSF) in the diagnosis of MS Florian Deisenhammer Harald Hegen Dept. of Neurology Innsbruck Medical University

Peer reviewed by ParadigMS

www.paradigms.foundation

Abstract The diagnosis of multiple sclerosis (MS) is a complicated process, requiring the condition to be differentiated from other MS mimics – diseases that might appear similar at first to MS but which are distinguished by their own set of specific characteristics. As analytical techniques have evolved, the cerebrospinal fluid (CSF) has become a highly specific and sensitive tool to support the diagnosis of MS. In this ParadigMS Foundation presentation, Professor Florian Deisenhammer shares his knowledge of the use of specific biomarkers in CSF such as oligoclonal bands and kappa free light chains to demonstrate the chronic inflammatory nature of MS. This workshop will serve as an excellent educational resource for all neurologists aiming to further their knowledge and skill in relation to the diagnosis, care and management of MS patients.

2

ParadigMS Foundation

Disclaimer

ParadigMS is an independent and non-profit international group of Multiple Sclerosis experts dedicated to improving Multiple Sclerosis patient care.

The author(s) hereby grant(s) ParadigMS the nonexclusive right to distribute and publish this slide deck on the ParadigMS platform (for users with an online account only). The author, who is compensated for the creation of this slide deck, retains the right to make changes to this slide deck as he sees fit.

It contributes to an increased knowledge of Multiple Sclerosis Patient’s care by generalist neurologists and other care-givers (nurses, general practitioners,…) by translating science into clinically relevant medical education to the local level in individual countries.

ParadigMS is independent in the research it conducts, in the educational programs it elaborates, in the opinion that it expresses.

The foundation’s origin is European with board members working in 23 different European, Middle-Eastern and NorthAfrican countries.

ParadigMS is a non-profit foundation and does not sell or make a profit from the distribution of the educational slide deck to health care practitioners. ParadigMS can charge a fee to non-health care practitioners for the use of its digital platform that gives access to all educational content (including the slide decks).

The author remains responsible for observing all copyrights or other intellectual property rights related to the figures, data and research results used in the slide deck.

Board Members should be active Multiple Sclerosis clinicians and researchers.

3

ParadigMS’ Peer Review Process All ParadigMS slide decks are presented and peer reviewed at expert meetings.

Once the peer review process is completed, the slide deck is published on the ParadigMS website and used in educational and training activities.

The experts and board members of ParadigMS

Laura Airas (Finland, University of Turku) Raed Al Roughani (Kuwait, MS clinic at Ibn-Sina hospital & Amiri Hospitals Kuwait) Mona Alkhawajah (Saudi Arabia, King Faisal Specialist Hospital & Research Centre Riyadh) Thomas Berger (Austria, Medical University of Vienna) Alexey Boyko (Russia, Russian State Medical University and MS Center) Lou Brundin (Sweden, Karolinska Institutet Stockholm) Andrew Chan (Switzerland, University Hospital Bern) Florian Deisenhammer (Austria, Medical University of Innsbruck) Paolo Gallo (Italy, University of Padova) Nikolaos Grigoriadis (Greece, Aristotle University of Thessaloniki) Hans-Peter Hartung (Germany, Heinrich-Heine-University Dusseldorf) Christoph Kleinschnitz (Germany, Essen University Hospital) Ralf Linker (Germany, University of Regensburg) Melinda Magyari (Denmark, Danish Multiple Sclerosis Center) Celia Oreja-Guevara (Spain, Hospital Clinico San Carlos Madrid) Carlo Pozzilli (Italy, University of Roma La Sapienza) Veronica Popescu (Belgium, University MS Center Pelt –Hasselt) Maura Pugliatti (Italy, University of Ferrara) Bart Van Wijmeersch (Belgium, University MS Center Pelt -Hasselt) Patrick Vermersch (France, University of Lille) Bassem Yamout (Lebanon, American University of Beirut Medical Center) Magd Zakaria (Egypt, Egyptian Society of Multiple Sclerosis) Tjalf Ziemssen (Germany, Carl Gustav Carus University Hospital Dresden)

4

A short history Criteria

Requirements

Diagnosis of RR-MS

Timepoint 1

Details

Timepoint 2

episode no.1

+ relapse no.1

Clinical diagnosis Two relapses affecting two separate sites within the CNS

Poser 1983

episode no.1

+ relapse no.1

Laboratory-assisted diagnosis Positive CSF and evidence for paraclinical abnormalities (MRI or VEP) at a separate site replaces second relapse

McDonald 2001/2005/2010

episode no.1

Schumacher 1965

+

MRI

DIS

DIT

MRI-assisted diagnosis MRI evidence for DIS and DIT replaces second relapse

Definitions: CNS: central nervous system; CSF: cerebrospinal fluid; DIS: dissemination in space; DIT: dissemination in time; MRI: magnetic resonance imaging; VEP: visual evoked potential

5

What’s positive CSF? McDonald Criteria Ann Neurol 2001;50:121-7

CSF abnormality: – OCB (preferably by IEF) and/or – Elevated IgG Index – WBC < 50/mm3 – State of the art technology

Definitions: CSF: cerebrospinal fluid; IEF: isoelectric focusing; Ig: immunoglobulin; OCB: oligoclonal bands; WBC: white blood cell

Positive CSF • In context with MS “positive CSF” means detection of intrathecal synthesis of immunoglobulins as a surrogate of chronic immune activation  DIT • Surrogates of acute inflammation, i.e. elevated cell counts are not suggestive of a “positive CSF”

Definitions: CSF: cerebrospinal fluid; DIT: dissemination in time

7

Intrathecal immunoglobulin synthesis Blood-CSF-barrier Blood

CSF

Albumin IgG IgA

Filtration

Intrathecal Ig synthesis

IgM

Definitions: CSF: cerebrospinal fluid; Ig: immunoglobulin

Semiquantitative total IgG

•

IgG Index=

IgG CSF : IgG Serum Alb CSF : Alb Serum

Normal: <0.7

Definitions: Alb: albumin; Ig: immunoglobulin.

Reiber formula QAlb

IgG Index

IgA Index

IgM Index

5 10 20 40 80 100

0,65 0,68 0,72 0,76 0,78 0,78

0,46 0,46 0,53 0,61 0,66 0,67

0,22 0,28 0,39 0,49 0,56 0,58

Intrathecal Ig concentration IgLoc = [ QIg – (a/b √(QAlb)2 + b2 – c) ] x IgSerum

[mg/l]

Intrathecal Ig fraction IgIF = [ 1 – (a/b √(QAlb)2 + b2 – c) / QIg ] x 100

Definitions: Alb: albumin; Ig: immunoglobulin.

[%]

Auer & Hegen formula

Auer M, et al. Eur J Neurol. 2016 Apr;23(4):713-21

Diagnostic performance of quantitative formulae

73 95

At onset

Definite MS

Bourahoui A, et al. Eur J Neurol. 2004 Aug;11(8):525-9; Freedman MS, et al. Arch Neurol. 2005 Jun;62(6):865-70.

13

IgG Index vs. OCB 647 patients with IgG index > 0.6 100

DMD IND OND Borr.

Total

% of OCB

80 60 40

SAH excluded!

20 0

 demyelinating neurol. diseases (n=295)  inflammatory neurol. diseases (n=197)  other neurol. diseases (n=137)  neuroborreliosis (n=18)

0.600.63

0.630.67

0.680.76

0.760.89

0.901.18

1.191.1.96

2.007.75

IgG index

Ig: immunoglobulin; OCB: oligoclonal bands; SAH: subarachnoid haemorrhage Mayringer I, et al. Eur J Neurol. 2005

In 30% of MS patients clonal expansion occurs without elevated total IgG!

IEF patterns CSF

Ser

IEF followed by immunostaining for IgG Definitions: CSF: cerebrospinal fluid; IEF: isoelectric focusing; Ig: immunoglobulin

Sensitivity and specificity of oligoclonal bands

Deisenhammer F, et al. Eur J Neurol. 2006 Sep;13(9):913-22

CSF in diagnostic criteria 2005 and 2010

If imaging or other tests (for instance, CSF) are undertaken and are negative, extreme caution needs to be taken before making a diagnosis of MS, and alternative diagnoses must be considered.

CSF: cerebrospinal fluid Polman CH, et al. Ann Neurol. 2011 Feb;69(2):292-302

Normal CSF!

CSF: cerebrospinal fluid Solomon AJ, et al. Neurology. 2016 Sep 27;87(13):1393-9

2017 diagnostic MS criteria in RMS

CSF: cerebrospinal fluid; DIS: dissemination in space; DIT: dissemination in time; MRI: magnetic resonance imaging; Thompson AJ, et al. Lancet Neurol. 2018 Feb;17(2):162-173

Predictive value of OCB Clinically isolated syndromes (CIS): evidence that + IgG OB pose a risk for presenting a 2 nd attack independently of MRI findings:

CDMS: clinically definite MS; CIS: clinically isolated syndrome; Ig: immunoglobulin; MRI: magnetic resonance imaging; OB: oligoclonal bands; DMT: disease-modifying therapy Tintore M et al. Neurology. 2008;70:1079-1083. Tintore M et al. Brain. 2015;138:1863-1874.

DIS: dissemination in space; DIT: dissemination in time; OB: oligoclonal bands; Tintore M et al. Neurology. 2008;70:1079-1083. Tintore M et al. Brain. 2015;138:1863-1874.

Arrambide G et al. Brain. 2018;141:1075-1084

Prognostic value of OCB in CIS 

OCB+ in 60-70% of CIS patients



Conversion to CDMS best investigated in ON: – –

Nilsson et al., J Neurol 2005: Risk for CDMS after 15 years in OCB+ 49% vs. 23% in OCB- (p=0.02) Soderstrom et al., Neurology 1998 (n= 143, 72% OCB+)

fig: Probability not to develop MS OCB+ (n=103) vs. OCB- (n=40) OCB+ sensitivity for CDMS 96% specificity 42% PPV 49% NPV 95%

CDMS: clinically definite MS; CIS: clinically isolated syndrome; NPV: negative predictive value; OCB: oligoclonal bands; PPV: positive predictive value;

OC-IgM-B in MS Author

year

n Analyte

OCMB+

EDSS

Villar

2002

65 OCMB

30 (46%)

+

Villar

2003

29 OCMB

11 (38%)

+

Mandrioli

2008

64 OCMB

30 (47%)

+

Villar

2008

54

myelin lipid spec. OCMB

Thangarajh

2008

81

lipid spec.

OCMB

Method: IEF

Conversion to SPMS

+

+ 24 (30%)

+

+

New development

24

Intrathecal B cell activity in MS Blood-CSF barrier Blood

CSF

Albumin Ig

Filtration VL

Intrathecal synthesis

CL

VL

FLC

CL

B

C

CL

L

VL

VL

• Immunoglobulins and Free Light Chains (FLC) accumulate in CSF in case of an intrathecal B cell activity • Besides intact immunoglobulins, terminally differentiated B cells (plasma cells) produce Light Chains in excess.

• 3 IgG isotypes: IgG, IgA, IgM • 2 subtypes: 𝜿-FLC & 𝝀-FLC

CSF: cerebrospinal fluid; Ig: immunoglobulin Hegen H, et al. Wien Med Wochenschr. 2022 Nov;172(15-16):337-345

Meta anlysis k-FLC – diagnostic value for MS

FLC: free light chains; OCB: oligoclonal bands Hegen H, et al. Mult Scler. 2023 Feb;29(2):169-181

Marker

Sensitivity (range)

Specificity (range)

k-FLC

88 (52-100)%

89 (69-100)%

OCB

85 (37-100)%

92 (74-100)%

Mean difference

2

-4

Very similar findings in PPMS

FLC: free light chains Hegen et al. submitted

kFLC index is superior to other formulae

CSF: cerebrospinal fluid; FLC: free light chains; IF: intrathecal fraction; Ig: immunoglobulin Hegen H, et al. Clin Chem Lab Med. 2019 Sep 25;57(10):1574-1586

k-FLC index cutpoint (range: 2.4 – 20)

FLC: free light chains Hegen H, et al. Mult Scler. 2023 Feb;29(2):169-181

Heterogenicity of study populations mimics assay related performance

N Latex

FLC: free light chains; OCB: oligoclonal bands Hegen H, et al. Mult Scler. 2023 Feb;29(2):169-181

Freelite

KFLC and OCB concordance rates

The concordance was higher between OB and KFLC indexes compared to OB / KFLC indexes and IgG index The highest concordance occurred between OB and KFLC-6.6, followed by OB and KFLC-5.9

FLC: free light chains; Ig: immunoglobulin; OB: oligoclonal bands Arrambide G et al. Brain. 2022;45:3931-3942.

KFLC cutpoints by differentials Multicentric: MS n=675, CIS n=90, OIND n=297, NINDC n=559 (no MRI data available) KFLC index cut-offs:

Diagnostic performance, KFLC index vs OB

-MS/CIS vs NINDC: 8.92 -MS/CIS vs OIND: 11.56

The KFLC perform slightly better than OB

CIS: clinically isolated syndrome; KFLC: kappa free light chains; Ig: immunoglobulin; OCB: oligoclonal bands; OIND: other inflammatory CNS disorders; NINDC: noninflammatory CNS disorder controls Levraut M et al. Neurol Neuroimmunol Neuroinflamm. 2022;10:e200049.

OIND MOGAD (n=26) NMOSD (n=18) ADEM (n=10) idiopathic myelitis (n=29); Idiopathic optic neuritis (n=29) Neurosarcoidosis (n=17) CNS vasculitis (n=21); Sjögren syndrome (n=5) Neurolupus (n=5) Behçet’s disease (n=5) Idiopathic LETM (n=10) Undefined demyelinating disease (n=17) Autoimmune encephalitis (n=72);

Pachy/Leptomeningitis (n=7) Aseptic meningitis/meningoradiculitis (n=10) TolosaHunt (n=4) Vogt-Koyanagi-Harada syndrome (n=3); CAAri (n=6) Relapsing meningoencephalomyelitis (n=2); Hypophysitis (n=1

Levraut M et al. Neurol Neuroimmunol Neuroinflamm. 2022;10:e200049.

KFLC as prognostic marker independent of OCB status KFLC index in pati ents with CIS (Multi centre, n=88)

KFLC index: similar levels if OB negative, regardless of clinical status (CIS-CIS vs CIS-MS) Berek K et al. Neurol Neuroimmunol Neuroinflamm. 2021;8:e1005.

KFLC as a prognostic marker Single centre, n= 214 CIS. Results: General characteristics

Definitions: CIS: clinically isolated syndrome; DIS: dissemination in space; DIT: dissemination in time; KFLC: kappa free light chains; MRI: magnetic resonance imaging Arrambide G et al. Brain. 2022;45:3931-3942

KFLC vs OCB as a prognostic marker

The risk for second attack was very similar between KFLC-5.0 and KFLC-6.6 The highest risk for DIS and DIT was demonstrated for KFLC-5.9 Definitions: DIS: dissemination in space; DIT: dissemination in time; KFLC: kappa free light chains; OCB oligoclonal bands Arrambide G et al. Brain. 2022;45:3931-3942.

KFLC vs OCB as a prognostic marker

Both KFLC-5.0 and KFLC-6.6 had the highest sensitivity and a better specificity, with a slightly higher accuracy than OB Although the IgG index had the highest specificity, its sensitivity was lower than that of OB and KFLC indexes, yielding the lowest accuracy. Its NPV was also the lowest although the PPV was similar to that of OB and KFLC indexes DIS: dissemination in space; DIT: dissemination in time; Ig: immunoglobulin; KFLC: kappa free light chains; NPV: negative predictive value; OB oligoclonal bands; PPV: positive predictive value; Arrambide G et al. Brain. 2022;45:3931-3942.

Prognostic value by KFLC index Results: Estimating cut-offs by outcome

KFLC index cut-offs vary according to the outcome

DIS: dissemination in space; DIT: dissemination in time; KFLC: kappa free light chains; NPV: negative predictive value; PPV: positive predictive value; Arrambide G et al. Brain. 2022;45:3931-3942.

Free light chains in CSF combine advantages of OCB and total IgG measurements Intrathecal Ig synthesis

Intrathecal k-FLC synthesis

Qualitative

Quantitative Non-linear Function • Reiber1 / • Auer & Hegen2

Quantitative Different approaches

Oligoclonal IgG Bands3 •

•

Absolute CSF concentration

• • • •

Metric Easy & fast Rater-independent High diagnostic sensitivity

% IF

• • • •

Metric Easy & fast Rater-independent Moderate diagnostic sensitivity

• Nominal • Labour-intensive • Rater-dependent • High diagnostic sensitivity

CSF: cerebrospinal fluid; Ig: immunoglobulin; KFLC: kappa free light chains; OCB oligoclonal bands 1Reiber H. J Neurol Sci. 1994 Apr;122(2):189-203; 2 Auer M, et al. Eur J Neurol. 2016 Apr;23(4):713-21; 3 Freedman MS, et al. Arch Neurol. 2005 Jun;62(6):865-70

Steroids do not impact 𝜅-FLC in CSF 𝜅-FLC index

CSF 𝜅-FLC concentration

CSF: cerebrospinal fluid; KFLC: kappa free light chains Konen FF, et al. Cells. 2020 Mar 31;9(4):842. doi: 10.3390/cells9040842

Conclusion and take home messages • CSF is a highly specific and sensitive tool for the diagnosis of MS • The CSF diagnostic criteria (“positive CSF”) for MS apply for patients with a typical clinical demyelinating syndrome AFTER (!) exclusion of differentials (i.e. no better explanation) • The cut-off points for “positive CSF” – 2 or more CSF restricted OCB or elevated kFLC are made to demonstrate the chronic inflammatory nature of MS. These are NOT made to differentiate between MS and other inflammatory CNS disease • Of course, CSF can be useful for differential diagnosis, but other diagnostic criteria apply for the respective diseases • The primary purpose is to support the diagnosis (DIT criteria); however, there is also a prognostic value • New markers (kFLC) will increase availability, prognostic value and diagnostic performance • Many other biomarkers are discussed currently, but none have been used as MS diagnostic markers to date CSF: cerebrospinal fluid; DIT: dissemination in time; Ig: immunoglobulin; KFLC: kappa free light chains; OCB oligoclonal bands

42

Sponsors The sponsors give a sponsorship for the creation of the educational materials and communication activities without any influence on the content of the presentations.

43