Diagnostic value of neurofilaments in differentiating motor neuron disease from multifocal motor neuropathy

OBJECTIVE

To evaluate the performance of serum neurofilament light chain (NfL) and cerebrospinal fluid (CSF) phosphorylated neurofilament heavy chain (pNfH) as diagnostic biomarkers for the differentiation between motor neuron disease (MND) and multifocal motor neuropathy (MMN).

METHODS

This retrospective, monocentric study included 16 patients with MMN and 34 incident patients with MND. A subgroup of lower motor neuron (MN) dominant MND patients (n = 24) was analyzed separately. Serum NfL was measured using Ella automated immunoassay, and CSF pNfH was measured using enzyme-linked immunosorbent assay. Area under the curve (AUC), optimal cutoff values (Youden's index), and correlations with demographic characteristics were calculated.

RESULTS

Neurofilament concentrations were significantly higher in MND compared to MMN (p < 0.001), and serum NfL and CSF pNfH correlated strongly with each other (Spearman's rho 0.68, p < 0.001). Serum NfL (AUC 0.946, sensitivity and specificity 94%) and CSF pNfH (AUC 0.937, sensitivity 90.0%, specificity 100%) performed excellent in differentiating MND from MMN. Optimal cutoff values were ≥ 44.15 pg/mL (serum NfL) and ≥ 715.5 pg/mL (CSF pNfH), respectively. Similar results were found when restricting the MND cohort to lower MN dominant patients. Only one MMN patient had serum NfL above the cutoff. Two MND patients presented with neurofilament concentrations below the cutoffs, both featuring a slowly progressive disease.

CONCLUSION

Neurofilaments are valuable supportive biomarkers for the differentiation between MND and MMN. Serum NfL and CSF pNfH perform similarly well and elevated neurofilaments in case of diagnostic uncertainty underpin MND diagnosis.

Primary Sjögren's syndrome independently promotes premature subclinical atherosclerosis

OBJECTIVES

Cardiovascular comorbidities are common in patients with autoimmune diseases. This study investigates the extent of subclinical atherosclerosis in patients with primary Sjögren's syndrome (pSS). Correlations with clinical factors such as organ involvement (OI) or disease activity were analysed and oxLDL antibodies (oxLDL ab) were measured as potential biomarkers of vascular damage.

METHODS

Patients with pSS were consecutively included from the rheumatology outpatient clinic. Age- and sex-matched controls were recruited (2:1 ratio). Data collection was performed by a standardised questionnaire and Doppler ultrasound to evaluate the plaque extent and carotid intima-media thickness (cIMT). Propensity score matching included all cardiovascular risk (CVR) factors and corresponding laboratory markers.

RESULTS

Data were available for 299 participants (199 pSS/100 controls), aged 59.4 years (50.6-65.0), 19.1% male. After matching, the pSS cohort had greater cIMT (p<0.001) and plaque extent (OR=1.82; 95% CI 1.14 to 2.95). Subgroup analyses of patients with pSS revealed that OI was associated with increased cIMT (p=0.025) and increased plaque occurrence compared with patients without OI (OR=1.74; 95% CI 1.02 to 3.01). OxLDL ab tended to be lower in patients with plaque (p=0.052). Correlations of higher Oxidized Low Density Lipoprotein (oxLDL) ab with EULAR Sjögren's Syndrome Disease Activity Index (p<0.001) and anti-Sjögren's-syndrome-related antigen A autoantibodies (SSA/Ro antibodies) (p=0.026) were observed.

CONCLUSIONS

Subclinical atherosclerosis occurs earlier and more severely in patients with pSS. The difference in cIMT between pSS and controls seems mainly driven by patients with OI, suggesting that this subgroup is particularly at risk. OxLDL ab might protect against atherosclerotic progression in patients with pSS. CVR stratification and preventive medications such as Hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors should be discussed and further longitudinal studies are needed.

Comparative analysis of albumin quotient and total CSF protein in immune-mediated neuropathies: a multicenter study on diagnostic implications

Introduction

Blood-cerebrospinal fluid (CSF) barrier dysfunction is pivotal for diagnosing immune-mediated neuropathies, especially in spinal nerve root inflammation. Typically, either total CSF protein or the CSF to serum albumin ratio (QAlb) is measured. Total CSF protein measurements have limitations, notably its fixed reference value regardless of age, in contrast to the age-dependent reference for QAlb. Our goal was to evaluate both markers in patients with immune-mediated neuropathies.

Methods

In our multicenter research, we collected retrospective CSF data from patients suffering from immune-mediated neuropathies across four German research centers. These parameters were analyzed in relation to their clinical characteristics.

Results

Out of 419 samples, 36 (8.6%) displayed a notable variation between total CSF protein and QAlb values. A detailed analysis revealed that patients displaying elevated QAlb but normal total CSF protein levels were significantly younger at disease onset (p = 0.01), at the time of diagnosis (p = 0.005), and when undergoing lumbar puncture (p = 0.001) compared to patients with elevated CSF protein and normal QAlb levels. These effects were especially evident for the subgroup of samples derived by female patients.

Discussion

Our work confirms the crucial role of QAlb in diagnosing immune-mediated neuropathies and particularly its efficacy as a marker for evaluating the blood-CSF barrier in patients with an earlier disease onset. Considering the significance of the albumin quotient, its assessment is especially advisable in younger patients of female sex to avoid missing a potential barrier dysfunction that might be falsely negative when using total protein.

Cranial nerve involvement in patients with immune-mediated neuropathy: an observational blink reflex study

OBJECTIVE

This study aimed to assess cranial nerve involvement in a large adult cohort of patients with immune-mediated neuropathy undergoing immunoglobulin treatment by measuring blink reflex R1 latency prolongation in correlation with clinical findings and nerve conduction studies.

METHODS

104 patients underwent blink reflex examination and ulnar nerve conduction studies and were assessed by the Inflammatory Neuropathy Cause and Treatment disability score, the revised Amyotrophic lateral sclerosis functional rating scale (ALSFRS-R) and focused clinical examination.

RESULTS

Prolonged R1 latencies were identified in 23 of 104 patients (22.1 %). These patients had more severe functional impairments according to the ALSFRS-R, yet only five clinically presented with bulbar dysfunction, facial- or trigeminal nerve impairment. Overall R1 latency was inversely correlated to ulnar motor conduction velocity. In preliminary follow-up assessments under continuous immunoglobulin treatment, prolonged R1 latencies partially improved.

CONCLUSIONS

Cranial nerve involvement is a common feature in immune-mediated neuropathies and is associated with a more severe disease stage. Here, R1 prolongation was detected less frequently compared to previously reported untreated cohorts.

SIGNIFICANCE

Blink reflex studies can detect subclinical cranial nerve involvement in immune-mediated neuropathies. Further studies are needed to evaluate the clinical utility of measuring R1 latency.

Monocyte chemoattractant protein 1 as a potential biomarker for immune checkpoint inhibitor-associated neurotoxicity

BACKGROUND

Oncological patients can benefit substantially from treatment with immune checkpoint inhibitors (ICI). However, there is a growing awareness of immune-related adverse events (irAE). Especially ICI-mediated neurological adverse events (nAE(+)), are tough to diagnose and biomarkers to identify patients at risk are missing.

METHODS

A prospective register with prespecified examinations was established for ICI treated patients in December 2019. At the time of data cut-off, 110 patients were enrolled and completed the clinical protocol. Herein, cytokines and serum neurofilament light chain (sNFL) from 21 patients were analyzed.

RESULTS

nAE of any grade were observed in 31% of the patients (n = 34/110). In nAE(+) patients a significant increase in sNFL concentrations over time was observed. Patients with higher-grade nAE had significantly elevated serum-concentrations of monocyte chemoattractant protein 1 (MCP-1) and brain-derived neurotrophic factor (BDNF) at baseline compared to individuals without any nAE (p < 0.01 and p < 0.05).

CONCLUSION

Here, we identified nAE to occur more frequently than previously reported. Increase of sNFL during nAE confirms the clinical diagnosis of neurotoxicity and might be a suitable marker for neuronal damage associated with ICI therapy. Furthermore, MCP-1 and BDNF are potentially the first clinical-class nAE predictors for patients under ICI therapy.

Clinical and paraclinical features of small fiber neuropathy in Sjögren's syndrome

Sjögren's syndrome is a potentially treatable cause of Small Fiber Neuropathy (SFN)-a condition that severely affects patients' quality of life. We therefore aimed to characterize patients with SFN and Sjögren's syndrome to raise awareness of this disease and facilitate its early recognition as an essential step for appropriate treatment. In 97 SFN patients (median age 48 years, 77% female), we studied the clinical features associated with Sjögren's syndrome compared to the idiopathic SFN subtype. According to the current ACR/EULAR classification criteria (Shiboski et al., Ann Rheum Dis 76:9-16, 2017), 24/97 individuals (25%, median age 48.5 years, 75% female) were diagnosed with Sjögren's syndrome. We did not observe any differences in SFN-defining sensory plus symptoms. Furthermore, intraepidermal nerve fiber densities (IENFD) were significantly lower in patients with SFN and Sjögren's syndrome (mean 2.6 ± 1.2/mm) compared to patients with idiopathic SFN (mean 3.2 ± 1.5/mm; p = 0.048). There were no significant group differences when analyzing cerebrospinal fluid (CSF) parameters. We conclude that Sjögren's syndrome-associated SFN is difficult to distinguish from idiopathic forms based on initial clinical symptoms and CSF results. However, lower IENFD values in patients with Sjögren's syndrome-associated SFN might indicate a distinct different pathomechanism in this entity compared to idiopathic SFN.

Premature stroke and cardiovascular risk in primary Sjögren's syndrome

Introduction

Primary Sjögren's syndrome (pSS) is associated with an increased prevalence of traditional risk factors and cardiovascular diseases (CVDs). The study aimed to identify specific risk factors for CVD in pSS patients.

Methods

PSS patients with and without CVD were compared. All patients fulfilled the EULAR/ACR classification criteria. Patients with CVD presented at least one of the following manifestations: myocardial infarction, transient ischemic attacks, ischemic or hemorrhagic stroke, peripheral artery disease, coronary artery disease, and carotid plaques. Data were collected by a standardized protocol and review of medical records.

Results

61/312 (19.6%) pSS patients presented with CVD. Traditional risk factors such as hypertension, hypercholesterinemia and diabetes (p < 0.05), pSS manifestations, in particular vasculitis (p = 0.033) and Raynaud's phenomenon (p = 0.018) were associated with CVD. Among patients with ischemic events (28/312, 9%), particularly cerebrovascular disease (n = 12/28, 42.9%), correlations with increased EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) (p = 0.039) and EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) (p = 0.048) were observed. Age at first cerebrovascular event was 55.2 [48.9-69.6] years. Multivariate analysis confirmed hypertension [odds ratio (OR) 3.7, 95% confidence interval (CI) 1.87-7.18, p < 0.001], hypercholesterinemia (OR 3.1, 95% CI 1.63-5.72, p < 0.001), male gender (OR 0.4, 95% CI 0.17-0.78, p = 0.009), Raynaud's phenomenon (OR 2.5, 95% CI 1.28-4.82, p = 0.007), and CNS involvement (OR 2.7, 95% CI 1.00-7.15, p = 0.048) as independent CVD predictors.

Conclusion

Raynaud's phenomen as well as vasculitis and high ESSDAI have shown a significant association to CVD. PSS patients with cerebrovascular events were younger than expected. Knowledge about risk factors may help clinicians to identify pSS patients at risk for CVD. After diagnosis of pSS, patients should be screened for risk factors such as hypertension and receive appropriate therapy to prevent or at least reduce sequelae such as infarction. However, further investigations are necessary in order to achieve a reliable risk stratification for these patients.

Saliva Free Light Chains in Patients with Neuro-Sjögren

Background: Sjögren’s syndrome (SS) is an autoimmune disease characterized by sicca symptoms and various extra-glandular manifestations. The diagnosis of SS requires sicca symptoms, anti-SSA(Ro)-antibody positivity, and/or pathological focus scores on a minor salivary gland biopsy. Previous studies have investigated different biomarkers in order to avoid invasive diagnostic procedures. It was found that kappa and lambda free light chains (KFLC and LFLC) in saliva are specific for SS. Methods: FLC concentrations in saliva and serum were determined in 130 patients—50 with SS and neurological involvement (Neuro-Sjögren) and 80 neurological controls. The EULAR SS disease activity index and patient reported index (ESSPRI) were determined in patients with SS. Results: Patients with SS revealed increased pain and decreased saliva production according to the ESSPRI and Saxon test, respectively, with increasing FLC concentrations in the saliva. No significant differences in serum and salivary protein concentrations were observed between patients with SS and controls. Conclusion: KFLC and LFLC concentrations in saliva are not suitable to distinguish patients with Neuro-Sjögren and neurological control subjects, thus a diagnostic biopsy is still required. The association of salivary KFLC and LFLC concentrations with saliva production and ESSPRI pain score suggests a complex relationship between dryness and pain in patients with SS.

Versorgungssituation von CIDP-Patienten in neun deutschen Zentren des Neuritis Netzes

Hintergrund

Die Diagnose und Behandlung von Patienten mit immunvermittelten Polyneuropathien ist aufgrund der Heterogenität der Erkrankungen herausfordernd.

Ziel der Arbeit

Ein aktueller epidemiologischer Überblick über die Versorgungssituation von Patienten mit immunvermittelten Polyneuropathien innerhalb des deutschen Neuritis-Netzwerks „Neuritis Netz“.

Material und Methoden

Es erfolgte eine Umfrage in neun deutschen neurologischen Zentren, die auf die Betreuung von Patienten mit Immunneuropathie spezialisiert sind. Wir erfassten Diagnose, Vorgehen in der Diagnostik und Nachsorge, typische Symptome bei Manifestation und im Krankheitsverlauf sowie Therapiedaten.

Ergebnisse

Die Erhebung umfasst Daten von 1529 jährlich behandelten Patienten mit Immunneuropathien, 1320 davon mit chronisch inflammatorisch demyelinisierender Polyneuropathie (CIDP). Die Diagnostik umfasste fast immer Lumbalpunktionen sowie Elektroneuro- und -myografien entsprechend den aktuellen Leitlinien. Der Einsatz von Ultraschall, Biopsie und MRT war unterschiedlich. Wichtigster klinischer Parameter zum Therapiemonitoring in allen Zentren war die motorische Funktion in den klinischen Nachuntersuchungen. Zur Erhaltungstherapie wurde bei rund 15 % der Patienten ein breites Spektrum unterschiedlicher Immunsuppressiva eingesetzt.

Diskussion

Die Studie liefert wichtige epidemiologische Daten zur aktuellen Versorgungsituation von Patienten mit Immunneuropathien in Deutschland. Die Weiterentwicklung spezifischer Empfehlungen zur Therapie und Nachverfolgung von CIDP-Patienten ist notwendig, um einen einheitlichen Standard der Patientenversorgung zu gewährleisten. Dieses wird durch die strukturierte Zusammenarbeit von Exzellenzzentren wie dem deutschen Neuritis Netz erheblich unterstützt.

Trigeminal Nerve Affection in Patients with Neuro-Sjögren Detected by Corneal Confocal Microscopy

Background: Patients with Sjögren’s syndrome and polyneuropathy more frequently develop cranial nerve affection when compared to patients with chronic inflammatory demyelinating polyneuropathy (CIDP). We therefore aimed to analyze trigeminal corneal nerve fibre characteristics in both patient groups. Methods: A total of 26 patients with Sjögren’s syndrome associated neuropathy and 29 patients with CIDP were recruited at our university hospital and compared to 6 healthy controls. Dry eye symptoms and signs were assessed via clinical examination and the Ocular Disease Surface Index questionnaire. Trigeminal corneal nerve fibres were analyzed via corneal confocal microscopy (CCM) as a non-invasive in vivo microscopy. Results: CCM revealed significantly reduced corneal nerve fibre density and corneal nerve fibre main branch density in the Neuro-Sjögren group when compared with healthy controls. There were no significant group differences between the Neuro-Sjögren and the CIDP group for any of the microscopic parameters. Dry eye assessment showed similarly reduced scores for both patient groups, while healthy controls showed better results for objective dry eye signs. There was no correlation between microscopic parameters of the corneal confocal microscopy and parameters of dry eye assessment. Conclusions: Our data revealed trigeminal corneal nerve affection in patients with neuropathy associated with Sjögren’s syndrome and patients with CIDP detected by CCM. No difference was found between both neuropathy groups indicating that CCM is not able to distinguish between both entities.

POS0789 CLINICAL FEATURES OF SJÖGREN’S SYNDROME WITH AND WITHOUT NEUROLOGICAL INVOLVEMENT (NEURO-SJÖGREN)

Background

Sjögren’s Syndrome is well known for its characteristic sicca symptoms due to autoinflammatory destruction of the salivary and lacrymal glands, but neurological involvement is also common in this entity. Nevertheless, previously published smaller studies suggested distinct clinical features for Sjögren’s syndrome with and without neurological involvement, such as a more balanced gender distribution and lower IgG levels in patients with Sjögren‘ syndrome and neurological involvement1,2.

Objectives

We therefore aimed to systematically assess clinical features of patients with Sjögren’s syndrome with and without neurological involvement, find relevant in-between group differences and hereby aid early detection of both patient groups in the clinical routine to facilitate further studies, potentially with new therapeutic approaches.

Methods

We retrospectively assessed patients with Sjögren’s syndrome treated at the neurological and rheumatological/ immunological departement of our university hospital between 05/2014 and 09/2021 for available laboratory and clinical data. The displayed data represent preliminary results of this ongoing study.

Results

405 patients, who fulfilled the current ACR/EULAR classification criteria for Sjögren’s syndrome3 were currently included in the study (median age 59years [IQR 50-70 years], median ESSDAI 10 [IQR 3-16]). 228 patients (56%) showed neurological involvement. They were significantly more often male (32% vs. 14%; p<0.001) and showed lower IgG serum levels (median 11 g/l [IQR 9-13 g/l] vs 12 g/l [IQR 10-16 g/l], p<0.01) in comparison to patients with Sjögren’s syndrome but without neurological involvement. However, presence of objective xerostomia, objective xerophthalmia, SSA(Ro)-antibody-positivity or sialadenits grade 3 or 4 (Chisholm and Mason) on salivary gland biopsy did not differ between the two groups.

Conclusion

Preliminary analysis of this ongoing study supports the hypothesis, that patients with Sjögren’s syndrome and neurological impairment might express a distinct clinical phenotype in comparison to patients with Sjögren’s syndrome but without neurological involvement.

References

[1]Sjögren’s syndrome should be considered in patients with motor neuropathy. Zeitschrift fur Rheumatologie 2020; 79: 707–709.

[2]Seeliger T, Prenzler NK, Gingele S, et al. Neuro-Sjögren: Peripheral neuropathy with limb weakness in Sjögren’s syndrome. Front Immunol 2019; 10: 1600.

[3]Shiboski CH, Shiboski SC, Seror R, et al. 2016 American College of Rheumatology/European League Against Rheumatism classification criteria for primary Sjögren’s syndrome. Ann Rheum Dis 2017; 76: 9–16.

Disclosure of Interests

Tabea Seeliger: None declared, Emelie Kramer: None declared, Franz F. Konen: None declared, Sonja Beider: None declared, Alexandra Jablonka: None declared, Torsten Witte: None declared, Thomas Skripuletz Employee of: Honoraria for lectures: Alexion, Alnylam, Bayer Vital, Biogen, Celgene, CSL Behring, Euroimmun, Janssen, Merck Serono, Novartis, Pfizer, Roche, Sanofi, Siemens, Diana Ernst Consultant of: Participation in Advisory Boards: Abbvie, Galapagos, Amgen, Novartis, Employee of: Fees for Presentations: Abbvie, Amgen, BMS, Chugai, Cilag-Janssen, Galapagos, GSK, Medac, Lilly, Pfizer, Novartis, Roche

POS0737 SICCA SYNDROME: A MULTIMODAL ASSESSEMENT TO CHARACTERIZE PATIENT COHORTS BEYOND SJÖGREN’S SYNDROME CLASSIFICATION CRITERIA

Background

Sicca syndrome represents a heterogeneous group of conditions, including Sjögren syndrome, causing xerophthalmia and xerostomia.

Objectives

This study characterizes in depth patients with Sicca syndrome and evaluates salivary gland ultrasound (SGUS) in this cohort.

Methods

Principal component analysis and hierarchical clustering of clinical parameters, including ESSPRI, ESSDAI and laboratory data were performed on all referrals for assessment of Sicca symptoms between October 2018 and March 2021. SGUS and labial gland biopsies were compared across groups.

Results

583 patients were assessed. Objective dryness was confirmed in 73% of patients. Cluster analysis identified 3 groups with post-hoc analysis confirming distinct phenotypes: Somatic Group (283/583; 49%) with higher reported symptoms but limited objective dryness; Dry Without Autoimmune Features (DAFneg, 206/532; 35%) and Dry With Autoimmune Features (DAFpos, 94/532; 16%). DAFpos patients had highest autoantibody titres (SSA 240 vs 3.6 vs 3.8; p<0.001), most extra-glandular manifestations (p<0.001) and highest median SGUS Score (DAFpos: 8 [IQR 4-10] vs SG: 2 [1-4] vs DAFneg 4 [2-5]; p< 0.001). No tangible correlation primary Sjögren syndrome criteria was observed.

Conclusion

SGUS score correlated with a subset of Sjögren syndrome patients, identified in the DAFpos cluster. This study highlights heterogeneity within Sicca and indeed Sjögren syndrome, highlighting the need for further studies.

References

[1]Chisholm DM, Mason DK. Labial salivary gland biopsy in Sjogren’s disease. J Clin Pathol. 1968;21(5):656-60

[2]De Vita S, Lorenzon G, Rossi G, Sabella M, Fossaluzza V. Salivary gland echography in primary and secondary Sjogren’s syndrome. Clin Exp Rheumatol. 1992;10(4):351-6

Table 1.

Comparing and contrasting the clinical demographics and attributes of the entire cohort subdivided into the three groups identified through principal component analysis and subsequent hierarchical clustering. Results are shown as mean and interquartile range unless otherwise stated.

SomaticDAFnegDAFposp N (%)283(49)206(35)94(16) Female, n (%)239(84)142(69)81(86%)<0.001 Age at Onset, yrs47.3[36.6-55.9]60.2[51.1-67.3]50.1[35.5-59.4]<0.001 BMI, kgm-226.1[23.0-31.0]24.7[21.7-27.7]24.6[22.4-28.0]0.003 Smoker, n (%)50(18)15(7)4(4)0.06ESSPRI Scores  - Dryness6[3-7]2[1-3]4[2-7]<0.001  - Limb Pain7[5-8]5[2-6]6[4-8]  - Fatigue8[6-9]3[2-5]5[3-8]Reported Symptoms Raynaud, n (%)86(30)51(25)44(47)0.006 Arthralgia, n (%)222(78)118(57)61(65)0.002 Myalgia, n (%)197(70)87(42)40(43)0.003 Stiffness, n (%)98(35)37(18)23(25)0.001 Parotitis, n (%)62(22)24(12)33(35)0.001 Sand corn, n (%)168(59)62(30)44(47)0.001 Ocular Inf, n (%)120(42)45(22)26(27)0.005ESSDAI  - Score5[2-12]5[0-11]11[4-17]<0.001Antibody Titres  - ANA ≥ 1:160178(63)152(74)44(47)<0.001  - RhF U/ml10.0[10.0-10.9]10.0[10.0-11.3]23.3[11.7-71.0]<0.001 - Alpha-Fodrin U/ml9[5-22]9[6-19]12[6-25]0.05  - anti-SSA(Ro) U/ml3.6[0.3-101.3]3.8[0.3-102.3]240.0[192.8-240.0]<0.001  - anti-SSB(La) U/ml0.4[0.3-3.4]0.3[0.3-1.9]73.1[3.8-312.5]<0.001Measurable Dryness Saxon, g3.5[2.4-4.9]4.2[3.3-5.3]2.3[0.6-3.7]<0.001 Schirmer, mm7.0[2.0-17.9]3.0[0.5-12.0]2.5[0.0-7.1]<0.001Labial Gland Biopsy, n (%) - Biopsy performed150(53)120(58)18(19) - Chisholm Score ≥366(44)64(53)9(50) - Median Score2[1-3]3[2-3]3[3-4]Salivary Gland Ultrasound, n (%) - SGUS = 039(14)39(19)1(1) - SGUS ≥673(26)55(27)38(41) SGUS Score2[1-4]4[2-5]8[4-10]<0.001Figure 1.

A 3D scatterplot composed of the first 3 dimensions of the principal component analysis, identified as providing greatest inertia gain on hierarchical clustering. The Somatic Group (SG) are represented by the black points. Patients in the Dryness without autoimmune features (DAFneg) are represented by pink points and Dryness with autoimmune features (DAFpos) patients with green dots.

Acknowledgements

We would like to express our gratitude to the staff of the Rheumatology Outpatients Department at Hannover Medical School for their continual help in organization of patients: G Mielke, A Lahn, Dr. S Hirsch.

Disclosure of Interests

Emelie Kramer: None declared, Tabea Seeliger: None declared, Thomas Skripuletz: None declared, Vega Gödecke: None declared, Sonja Beider: None declared, Alexandra Jablonka: None declared, Torsten Witte: None declared, Diana Ernst Grant/research support from: This study was financially supported by Novartis. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication.

Multimodal Assessment and Characterization of Sicca Syndrome

Background: Sicca syndrome represents a heterogeneous group of conditions, such as Sjögren syndrome, causing xerophthalmiaand xerostomia. This study characterizes in depth patients with Sicca syndrome and evaluates salivary gland ultrasound (SGUS).

Methods: Principal component analysis and hierarchical clustering of clinical parameters, such as ESSPRI, ESSDAI and laboratory data, were performed on all referrals for assessment of Sicca symptoms between October 2018 and March 2021. SGUS and labial gland biopsies were compared across groups.

Results: A total of 583 patients were assessed. Objective dryness was confirmed in 73% of the patients. Cluster analysis identified 3 groups with post-hoc analysis confirming distinct phenotypes: Somatic Group (283/583; 49%) with more frequent symptoms but limited objective dryness; Dry Without Autoimmune Features (DAFneg, 206/584; 35%), and Dry With Autoimmune Features (DAFpos, 94/584;16%). DAFpos patients had highest autoantibody titers (anti-SSA(Ro) 240 vs. 3.6 vs. 3.8; p &lt; 0.001), most extra-glandular manifestations (p &lt; 0.001), and highest median SGUS Score (DAFpos: 8 [IQR 4–10] vs. SG: 2 [1–4] vs. DAFneg 4 [2–5]; p &lt; 0.001). No tangible correlation with primary Sjögren syndrome criteria was observed.

Discussion: SGUS score correlated with a subset of patients with Sjögren syndrome, identified in the DAFpos cluster. This study highlights heterogeneity within sicca and, indeed, Sjögren syndrome, highlighting the need for further studies.

Nerve ultrasound findings in Sjögren's syndrome-associated neuropathy

BACKGROUND AND PURPOSE

The phenotype of Sjögren's syndrome-associated neuropathy has been better characterized in recent years. However, Sjögren's syndrome-associated neuropathy remains an underdiagnosed entity with only few insights considering the pathomechanisms of nerve damage. Nerve ultrasound has proven to be a useful and efficient tool in detecting nerve damage of autoimmune origin. We, therefore, aimed to evaluate this method for Sjögren's syndrome-associated neuropathy.

METHODS

Patients with Sjögren's syndrome and clinical signs of neuropathy underwent sonographic examination of both median and ulnar nerves. Nerve thickening was classified for cross-sectional areas of >12 mm² at the median nerve and for >10 mm² at the ulnar nerve. Fascicle thickening was documented for cross-sectional areas ≥5 mm² at the median and ≥3 mm² at the ulnar nerve.

RESULTS

Forty-three patients were included in the analysis (median age 60 years [interquartile range 53-73 years], female rate 60%). 31/43 patients (72%) showed abnormalities on nerve ultrasound, while nerve thickening was found more frequently than fascicle thickening (90% vs. 52% of patients with sonographic abnormalities, respectively). Abnormal findings were observed more frequently at the median nerve and in proximal localization. Abnormal findings on nerve conduction studies were evident in 36/43 patients (84%). Nerve conduction studies revealed a tendency of demyelinating nerve damage patterns being associated with abnormal findings on nerve ultrasound.

CONCLUSIONS

In addition to nerve conduction studies, nerve ultrasound may have a supporting role in the diagnosis of Sjögren's syndrome-associated neuropathy. Also, our data support an immune-mediated inflammatory demyelinating pathogenesis of Sjögren's syndrome-associated neuropathy.

Switch from intravenous to subcutaneous immunoglobulin IgPro20 in CIDP patients: a prospective observational study under real-world conditions

Background:

IgPro20 is the first approved subcutaneous immunoglobulin (SCIg) preparation for the treatment of patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Two different doses of the SCIg preparation were investigated in the pivotal PATH study. Real-world data, and particularly the efficacy of an equivalent dose switch from intravenous immunoglobulin (IVIg) to SCIg, are still not available.

Methods:

In this prospective observational study, 41 patients with CIDP treated with intravenous immunoglobulin (IVIg) were changed to an equivalent (1:1) dose of IgPro20 1 week after last IVIg treatment. Patients were examined at the time of switch from IVIg to SCIg, after 3 and after 6 months and efficacy, treatment preferences and systemic and local reactions were assessed.

Results:

Various clinical outcome parameters demonstrated overall stability regarding disability, general activity and social participation, grip and muscle strength, as well as gait impairment. Treatment satisfaction remained unchanged between IVIg and SCIg therapy. However, 88% of patients favoured treatment with subcutaneous IgPro20 over IVIg 6 months after switch to IgPro20.

Conclusion:

Results demonstrate that the switch of IVIg to an equivalent dose of SCIg represents an effective and preferred treatment option for CIDP patients.

CIDP associated with Sjögren's syndrome

BACKGROUND

This study addresses the challenging characterisation and differentiation of CIDP versus CIDP in association with Sjögren's syndrome to facilitate the process in clinical routine.

METHODS

Patients with both CIDP and Sjögren's syndrome and CIDP without Sjögren's syndrome were compared concerning relevant differences in clinical, laboratory and electrophysiological findings. 154 patients who fulfilled the diagnostic EFNS/PNS criteria for CIDP were included in the analysis. 54 of these patients additionally fulfilled the ACR/EULAR classification criteria for Sjögren's syndrome.

RESULTS

The frequency of female patients was higher in patients with CIDP and Sjögren's syndrome (52%) versus CIDP patients without Sjögren's syndrome (28%). Furthermore, the occurrence of cranial nerve impairment was significantly higher in patients with Sjögren's syndrome (39% versus 14%). There were no significant group differences in the evaluation of initial symptoms, severity of disability judged by INCAT disability scale score, presence or distribution of sensory deficits, limb weakness and the presence of ataxia, pain or dysautonomia, CSF laboratory or electrophysiological findings.

CONCLUSIONS

In conclusion, our data indicate that cranial nerve impairment and female gender might represent red flags for an additional Sjögren's syndrome in patients with CIDP. The patterns of clinical disabilities and electrophysiological findings due to peripheral nerve damage are similar in both CIDP entities.

Hearing dysfunction in patients with Neuro-Sjögren: a cross-sectional study

Background

Sjögren's syndrome is an immunologically mediated disease with salivary and lacrimal gland destruction characterised by typical sicca symptoms of dry mouth and eyes. Awareness of extraglandular neurological manifestations such as polyneuropathy and affection of cranial nerves is rising. Hearing loss as consequence of involvement of the vestibulocochlear nerve presents a severe disability. The exact prevalence and nature of hearing dysfunction in patients with Neuro-Sjögren has been insufficiently evaluated to date.

Methods

Thirty patients with Sjögren's syndrome (ACR-EULAR classification criteria) and polyneuropathy were included in the study in the time period between 11/2016 and 03/2018. The median age was 59 years and 57% were females. Auditory function was investigated by pure tone audiometry, Freiburg speech comprehension audiometry, transient evoked otoacoustic emissions and brainstem evoked response audiometry.

Results

Pure tone audiometry revealed hearing loss in 10/30 patients (33%) with severity ranging from mild in most patients (60%) to severe in 10%. In addition, pathological audiometric test findings showed retrocochlear auditory dysfunction in 14 further patients. In total, 24/30 patients (80%) showed pathological test results on audiometric testing suggesting hearing dysfunction.

Conclusions

In conclusion, our results show that hearing dysfunction as a possible consequence of cranial neuropathy in patients with Neuro-Sjögren has been underestimated in previous studies.

Cognitive impairment in patients with Neuro-Sjögren

OBJECTIVE

Extraglandular neurological manifestations of Sjögren's syndrome are increasingly recognized, defining the disease entity of Neuro-Sjögren. Neuropsychological assessment of patients with Sjögren's syndrome has hitherto been performed on predominantly rheumatological cohorts. These studies revealed a wide variety of prevalence rates for cognitive impairment (22-80%), while variable cut-off criteria for detection of cognitive impairment were applied. Attentional functions have not yet been thoroughly investigated in these patients, although they clearly represent relevant aspects of cognitive functioning in daily life.

METHODS

We therefore conducted extensive neuropsychological assessment based on two neuropsychological test batteries [i.e., the extended German version of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery (CERAD-PLUS), and the test battery for attentional performance (TAP) as a well-established assessment of attentional functions in the German-speaking part of Europe].

RESULTS

Sixty-four patients with Neuro-Sjögren, who were treated at our university hospital between December 2016 and January 2019, were included. Evidence for the presence of cognitive impairment was found in 55% of patients with Neuro-Sjögren. The degree of cognitive impairment ranged from mild (38%) to severe (17%). Attentional and mnemonic subtests showed pronounced cognitive impairment in patients with Neuro-Sjögren.

INTERPRETATION

Our results suggest that a substantial proportion of patients with Neuro-Sjögren suffer from cognitive impairment, putatively as a corollary of attentional deficits, which might exert adverse effects on occupational abilities, other cognitive functions, and social role functioning.

Lung Involvement in Primary Sjögren's Syndrome-An Under-Diagnosed Entity

Interstitial lung disease (ILD) represents a frequent extra-glandular manifestation of primary Sjögren's Syndrome (pSS). Limited published data regarding phenotyping and treatment exists. Advances in managing specific ILD phenotypes have not been comprehensively explored in patients with coexisting pSS. This retrospective study aimed to phenotype lung diseases occurring in a well-described pSS-ILD cohort and describe treatment course and outcomes. Between April 2018 and February 2020, all pSS patients attending our Outpatient clinic were screened for possible lung involvement. Clinical, laboratory and high-resolution computed tomography (HRCT) findings were analyzed. Patients were classified according to HRCT findings into five groups: usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP), desquamative interstitial pneumonia (DIP), combined pulmonary fibrosis and emphysema (CPFE), and non-specific-ILD. Lung involvement was confirmed in 31/268 pSS patients (13%). One-third (10/31) of pSS-ILD patients were Ro/SSA antibody negative. ILD at pSS diagnosis was present in 19/31 (61%) patients. The commonest phenotype was UIP n = 13 (43%), followed by NSIP n = 9 (29%), DIP n = 2 (6 %), CPFE n = 2 (6 %), and non-specific-ILD n = 5 (16%). Forced vital capacity (FVC) and carbon monoxide diffusion capacity (D_LCO) appeared lower in UIP and DIP, without reaching a significant difference. Treatment focused universally on intensified immunosuppression, with 13/31 patients (42%) receiving cyclophosphamide. No anti-fibrotic treatments were used. Median follow-up was 38.2 [12.4–119.6] months. Lung involvement in pSS is heterogeneous. Better phenotyping and tailored treatment may improve outcomes and requires further evaluation in larger prospective studies.

[Severe polyneuropathy in primary Sjögren's syndrome : Sjögren's syndrome should be considered in patients with motor neuropathy]

A 64-year-old male patient developed over a period of 20 years a peripheral neuropathy symmetrically affecting the upper and lower limbs. The histological examination of a sural nerve biopsy revealed a severe axonal neuropathy. Despite extensive laboratory investigations including immunological and metabolic tests the origin could not be identified. Finally, a Schirmer test revealed xerophthalmia. A subsequent salivary gland biopsy from the lower lip revealed a grade III lymphocytic inflammation according to Chisholm and Mason and confirmed the diagnosis of Sjögren's syndrome.

Clinical, Radiological, and Laboratory Features of Spinal Cord Involvement in Primary Sjögren's Syndrome

Objective: To identify radiological and laboratory hallmarks in patients with primary Sjögren’s syndrome (pSS) presenting with spinal cord involvement. Methods: Clinical and laboratory routine parameters were analyzed in a retrospective multicenter case series of four patients who developed myelitis associated with pSS. Serological and cerebrospinal fluid (CSF) measurements of pSS associated anti-SSA(Ro)-antibodies were initiated, and CSF neurofilament light chain (NFL) levels were assessed. NFL values were compared with results from 15 sex- and age-matched healthy controls. Radiological assessment was performed using multi-sequence spinal cord magnetic resonance imaging. Results: Three of the four patients initially developed neurological signs suggestive of myelitis and were subsequently diagnosed with pSS. All patients presented a longitudinal spinal T2-hyperintense lesion in the cervical spinal cord, whereas only two patients showed pleocytosis and oligoclonal bands in the CSF. Median (range) CSF-NFL levels were significantly elevated in patients compared to controls (6672 pg/mL (621–50,000) vs. 585 pg/mL (357–729), p = 0.009). One patient showed sustained, highly increased NFL levels (50,000 pg/mL) in the initial assessment when radiological signs of axonal injury were still absent. Anti-SSA(Ro)-antibodies were found in the serum of three patients, while two patients additionally presented intrathecal anti-SSA(Ro)-antibody production. Elevated CSF-NFL levels and intrathecal synthesis of anti-SSA(Ro)-antibodies were associated with a relapsing and treatment-resistant disease course. Conclusion: Inflammatory spinal cord lesions associated with pSS are a rare but serious disease leading to severe disability. NFL and anti-SSA(Ro)-antibodies in CSF might serve as prognostic biomarkers and should be routinely assessed in patients with pSS.

Neuro-Sjögren: Peripheral Neuropathy With Limb Weakness in Sjögren's Syndrome

Objective: Sjögren's syndrome is a heterogeneous inflammatory disorder frequently involving peripheral nerves with a wide spectrum of sensory modalities and distribution patterns. The objective of this cross-sectional study was to determine characteristics of Sjögren's syndrome as a cause for severe neuropathy with limb weakness. Methods: One hundred and eighty four patients with polyneuropathy associated with limb weakness underwent routine diagnostics including investigations for Sjögren's syndrome. Forty-four patients with Sjögren's syndrome (ACR-EULAR classification criteria) and severe neuropathy were identified. Results: Sjögren's syndrome was found at a median age of 63 years and the gender distribution showed a balanced female-male ratio of 1:1. Anti-SSA(Ro) antibodies were detected in 48% while seronegative patients were diagnosed with Sjögren's syndrome based on sialadenitis on minor salivary gland biopsy with a focus score ≥1. The majority of patients (93%) were diagnosed with Sjögren's syndrome after neurological symptoms appeared. Limbs were symmetrically involved in 84% of patients (57% tetraparesis, 27% paraparesis). Sensory function was not affected in 11% of patients indicating that Sjögren's syndrome associated neuropathy can present as a pure motor syndrome. Electrophysiological measurements did not reveal pathognomonic findings (23% demyelinating pattern, 36% axonal pattern, 41% both demyelinating and axonal damage signs). More than half of our patients fulfilled the European Federation of Neurological Societies (EFNS) diagnostic criteria for CIDP indicating that distinction between Neuro-Sjögren and other causes of neuropathy such as CIDP is challenging. Interpretation: Our findings show that severe neuropathy with limb weakness is often associated with Sjögren's syndrome. This is of great importance in identifying and understanding the causes of immune mediated polyneuropathy.