Involvement of Nervous System Pathways in Primary Sjögren's Syndrome

OHIP-14 Scores in Patients with Sjögren's Syndrome Compared to Sicca Syndrome: A Systematic Review with Meta-Analysis

Objectives

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disorder characterized by dryness of mucous membranes, predominantly the eyes and mouth, following glandular tissue substitution. The onset of oral dryness constitutes a significant source of discomfort that negatively affects overall quality of life. This systematic review aimed at investigating the differences in Oral Health Impact Profile-14 (OHIP-14) questionnaire scores in patients diagnosed with Sjögren's syndrome compared to sicca syndrome, to assess the influence of the two conditions on oral health. Study Design. A systematic electronic and manual search was performed up to December 2023 for studies reporting OHIP-14 questionnaire scores in pSS patients versus sicca syndrome. Two authors independently reviewed, selected, and extracted the data. The outcome was the assessment of OHIP-14 scores in studies comparing pSS- and sicca syndrome-affected patients. Meta-analysis was conducted on available quantitative data.

Results

Literature search retrieved 30 articles, and 3 articles met the criteria for inclusion in the review. Meta-analysis revealed significantly higher scores in patients with sicca syndrome compared to pSS, although salivary flow was markedly reduced in pSS.

Conclusions

While offering supplementary information to standard tests and supporting the assessment of pSS and sicca syndrome patients, further validation is necessary to establish OHIP-14 validity in determining the impact of pSS and sicca syndrome on patients' quality of life.

Clinical features and high-risk indicators of central nervous system involvement in primary Sjögren's syndrome

BACKGROUND

Evidence for central nervous system involvement in primary Sjögren's syndrome (pSS) patients is controversial and extremely limited. We aimed to describe the clinical profiles and high-risk indicators of primary Sjögren's syndrome (pSS) patients with central nervous system (CNS) involvement (pSS-CNS).

METHODS

A total of 412 participants with pSS from a hospital in China from January 2012 to December 2019 were enrolled in the retrospective study. 42 pSS-CNS patients were compared with 370 pSS patients without CNS involvement. The clinical features, laboratory examinations, imaging characteristics, and treatment of the pSS-CNS cases were systematically analyzed. Potential risk factors related to pSS-CNS patients were identified by multivariate logistic regression analysis.

RESULTS

The prevalence of central nervous system involvement in the studied pSS patients was 10.2% (42/412), with 31.3% (14/42) of pSS patients having neurological manifestations as the initial symptom. The manifestations of hemiparesis (35.7%, 15/42), paraparesis (28.6%, 12/42), dysphonia (31.0%, 13/42), blurred vision (21.4%, 9/42), and dysfunctional proprioception (23.8%, 10/42) were more common in the pSS-CNS patients. Cerebral infarction (57.1%, 24/42), demyelination (31.0%, 13/42), myelitis (23.8%, 11/42), and angiostenosis (21.4%, 9/42) were most often found on MRI or CT scan imaging in the pSS-CNS patients. Intrathecal IgG level and total protein of cerebrospinal fluid were increased in 50% (8/16) of the pSS-CNS group. In comparison with patients without CNS involvement, the pSS-CNS patients were found to also have kidney and lung involvement, hematologic abnormalities, positive ANA and anti-SSA antibody tests, and reduced complement 3 (C3) and complement 4 (C4) levels (all p < 0.05). The prevalence of lung involvement, immune thrombocytopenia, and high-titer ANA (1:1000) were significantly higher in pSS-CNS disease activity compared to those in the moderately active group. Multivariate analysis identified lung involvement, anti-SSA positivity, and low C3 levels as prognostic factors for pSS-CNS. After high-dose glucocorticoids and immunosuppressive therapy, 60.5% (26/38) of pSS-CNS patients improved, 36.8% (14/38) were unresponsive to treatment, and 2.6% (1/38) died.

CONCLUSION

Clinical features are diverse in pSS-CNS patients, and the morbidity rate is low. CNS involvement was the initial presentation in state percentage here pSS patients. Pulmonary involvement, a positive anti-SSA antibody test, and reduced C3 levels are potential risk factors for CNS involvement in pSS. Treatment with high-dose glucocorticoids and immunosuppressive therapy appeared effective in 60% of pSS-CNS patients. Key Points • The CNS manifestations of pSS are diverse, and CNS imaging and CSF analysis are important for the diagnosis. • Pulmonary involvement, positive anti-SSA, and reduced C3 levels are potential risk factors of pSS-CNS. • About 60% of pSS-CNS patients were responsive to high-dose glucocorticoid administration and immunosuppressive therapy.

Motor neuron disease in a patient with overlap syndrome (rheumatoid arthritis; systemic lupus erythematosus, Sjogren's syndrome)

Autoimmune rheumatic diseases have their own specific clinical presentation, and can affect multiple systems. Neurological involvement of autoimmune rheumatic diseases may involve both the central and peripheral nervous systems. Inflammation of neural tissue, autoantibody-mediated reactions, and small vessel vasculitis may be effective in the pathogenesis of neuropathy in autoimmune rheumatological diseases. Autoimmune rheumatic disease with pure motor neuron involvement is very rare in the literature. The case is here presented of a 58-year-old female patient who presented with the complaints of increasing pain and weakness in the extremities and was diagnosed with lower motor neuron disease and overlap syndrome. The patient was treated with cyclophosphamide, pulse steroid, hydroxychloroquine and intravenous immunoglobulin. After 3 months of treatment, a significant improvement was observed in the patient's clinical complaints and laboratory parameters. In conclusion, some patients with undiagnosed autoimmune rheumatic diseases may have neurological complaints. Clinicians should investigate patients with such neurological complaints for autoimmune rheumatic diseases.

Acute polyneuropathy as the main manifestation of primary Sjogren’s syndrome: A case report

Sjogren's syndrome is an inflammatory disease affecting many systems. We report a Sjogren case with the presenting feature of an acute motor‐predominant polyneuropathy resembling Guillain–Barre syndrome. Upon further investigation, it was found that the patient had sicca symptoms for months. Scrupulous history should be taken to prevent a missed diagnosis.

Headache and immunological/autoimmune disorders: a comprehensive review of available epidemiological evidence with insights on potential underlying mechanisms

Several lines of evidence support a role of the immune system in headache pathogenesis, with particular regard to migraine. Firstly, alterations in cytokine profile and in lymphocyte subsets have been reported in headache patients. Secondly, several genetic and environmental pathogenic factors seem to be frequently shared by headache and immunological/autoimmune diseases. Accordingly, immunological alterations in primary headaches, in particular in migraine, have been suggested to predispose some patients to the development of immunological and autoimmune diseases. On the other hand, pathogenic mechanisms underlying autoimmune disorders, in some cases, seem to favour the onset of headache. Therefore, an association between headache and immunological/autoimmune disorders has been thoroughly investigated in the last years. The knowledge of this possible association may have relevant implications in the clinical practice when deciding diagnostic and therapeutic approaches. The present review summarizes findings to date regarding the plausible relationship between headache and immunological/autoimmune disorders, starting from a description of immunological alteration of primary headaches, and moving onward to the evidence supporting a potential link between headache and each specific autoimmune/immunological disease.

Vitamin D Deficiency, Osteoporosis and Effect on Autoimmune Diseases and Hematopoiesis: A Review

Vitamin D (VD) is essential for bone homeostasis, but it is also involved in pleiotropic effects on various organs and tissues. In adults, VD deficiency can cause or exacerbate osteoporosis and induce osteomalacia. However, every tissue and cell in the body has a VD receptor, including the brain, heart, stomach, pancreas, skin, gonads, and immune cells, and a deficiency may modify the function of these organs. Thus, the wide-ranging actions of VD help to explain why a reduction in VD amount has been correlated with numerous chronic diseases. In fact, VD deficiency increases the risk of osteoporosis and several other diseases and complications characterized by impaired bone metabolisms, such as autoimmune diseases, inflammatory bowel diseases, allergy, endocrinological diseases, hematological malignancies, and bone marrow transplantation. This review aims to investigate the link between VD deficiency, osteoporosis, and its concomitant diseases. Further epidemiological and mechanistic studies are necessary in order to ascertain the real role of hypovitaminosis in causing the reported diseases; however, adequate vitamin supplementation and restoration of metabolic normality could be useful for better management of these pathologies.

Barriers to translational research in Sjögren's syndrome with childhood onset: challenges of recognising and diagnosing an orphan rheumatic disease

Sjögren's syndrome was considered for many years a disease of adulthood, characterised by immune infiltration of exocrine glands, leading to dryness (eg, dry mouth and eyes), which is a cardinal symptom. As of the last 20 years, it became apparent that although the disease is very rare in children, its clinical presentation differs from that of adults, posing substantial challenges to the recognition, diagnosis, and classification of patients with childhood-onset Sjögren's syndrome. This Viewpoint explores comparative classification criteria for children (not validated) and adults with Sjögren's syndrome, as well as differences in the clinical presentation of childhood-onset versus adult-onset Sjögren's syndrome, offering ideas about how we can improve the diagnosis of Sjögren's syndrome in children. A review of the role of medical history and clinical assessment, serology, glandular function assessment, and imaging, as well as salivary and lachrymal gland biopsy in the diagnosis of children with Sjögren's syndrome is included. Additionally, we provide suggestions about further research and registry data collection that is required to address the unmet needs of these patients.

Prevalence and factors associated with osteoporosis and fragility fractures in patients with primary Sjögren syndrome

This study aimed at determining socio-demographic and clinical factors of primary Sjögren syndrome (pSS) associated with osteoporosis (OP) and fragility fracture. SJOGRENSER is a cross-sectional study of patients with pSS, classified according to American European consensus criteria developed in 33 Spanish rheumatology departments. Epidemiological, clinical, serological and treatment data were collected and a descriptive analysis was conducted. Bivariate and multivariate analyses were performed using a binomial logistic regression to study the factors associated with OP and fragility fracture in pSS. 437 patients were included (95% women, with a median age of 58.6 years). 300 women were menopausal (76.4%). Prevalence of OP was 18.5% [in men (N = 21) this measured 19%]. A total of 37 fragility fractures were recorded. In the multivariate analysis, there was an association between OP and age: in the 51-64 age range (menopausal women), the OR measured 9.993 (95% CI 2301-43,399, p = 0.002); In the age > 64 years group, OR was 20.610 (4.679-90.774, p < 0.001); between OP and disease duration, OR was 1.046 (1.008-1085, p = 0.017); past treatment with corticosteroids, OR 2.548 (1.271-5.105, p = 0.008). Similarly, an association was found between fragility fractures and age: in the 51-64 age group, OR measured 5.068 (1.117-22,995, p = 0.035), age > 64 years, OR was 7.674 (1.675-35,151, p < 0.009); disease duration, OR 1.049 (CI 1.003-1097, p < 0.036) and the ESSDAI index, OR 1.080 (1.029-1134, p = 0.002). Patients with pSS can develop osteoporosis and fragility fractures over the course of the disease. Age, corticosteroids treatment and disease duration were associated with the development of OP. Disease duration and ESSDAI were associated with the development of fractures in patients with pSS.

Polyneuropathy and the sural/radial sensory nerve action potential ratio in primary Sjögren's syndrome

Objectives: Polyneuropathy is the most common neurological complication in primary Sjögren's syndrome (pSS). A ratio of sural nerve and superficial radial nerve sensorial action potential amplitudes (SRARs) of <0.4 is an indicator for early axonal neuropathy. We evaluated the polyneuropathies and SRARs in pSS patients.Method: Fifty-two female patients who were diagnosed with pSS according to the European-American Consensus Criteria and 45 healthy controls were enrolled. Nerve conduction studies were performed to diagnose polyneuropathy. Sensory axonal polyneuropathy was diagnosed in three patients, so SRARs were compared in 49 patients and 50 healthy controls.Results: Fifty-two patients with pSS underwent nerve conduction tests. The sural sensory nerve action potential (SNAP) was <6 µV in threepatients and they were diagnosed with sensory axonal neuropathy. SRARs were evaluated in 49 female patients, with a mean age of 51.98 ± 10.79 years and 50 healthy controls with a mean age of 50.52 ± 12.55 years. The mean disease duration was 7.59 ± 6.17 years. The SRAR values were different between the patient and control groups. SRAR was <0.4 in 20.4% of the patient group and <0.4 in 6% of the control group. The SRAR value was not statistically different within the patient group based on anti-Ro and anti-La.Discussion: The potential for neurological involvement in patients with pSS who have no signs or injury should be evaluated because nervous system involvement in pSS is a negative prognostic factor. SRAR in patients with pSS can be used as a marker for the early detection of axonal neuropathy.

Epstein - Barr virus Infection in a Patient with Neuromyelitis Optica Spectrum Disorder and Sjögren's Syndrome: A Case Report and Review of Literature

BACKGROUND

The association of Neuromyelitis Optica Spectrum Disorders (NMOSD) with autoimmune disorders including Sjögren's syndrome (SS), is well recognized. Epstein Barr virus (EBV) has been associated to various neurological entities. We describe a case where EBV infection likely preceded NMOSD in a patient with unrecognized SS. The clinical features, work up and management are described.

CASE PRESENTATION

A 40-year woman with history of stroke and Guillain-Barre Syndrome (GBS) two years prior, presented with progressive lower extremity weakness and pain. Brain MRI revealed hyperintensities in the cerebellar and parietal lobes consistent with old infarcts, high intensity signal in the white matter and enhancing intramedullary lesion at the level of T2 and the conus medullaris. Cerebrospinal fluid (CSF) revealed no oligoclonal bands. Next day, the patient developed right ankle weakness and urinary incontinence. NMOSD was suspected and pulse steroids initiated. Patient's weakness resolved. Antinuclear antibodies (ANA), anti-SSA/SSB and Aquaporin 4 antibodies (AQP4Ab) were positive. CSF was positive for EBV. Parotid gland ultrasound revealed non-homogeneous tissue.Ganciclovir and plasmapheresis were started. The patient's sensation and motor deficits improved and one month after, she had regained motor power and sphincter control. The patient was discharged on oral prednisone and plans for rituximab infusions.On follow-up imaging, Spinal MRI showed areas of myelomalacia and complete resolution at the level of T2 and conus medularis lesions respectively. The patient had no additional flares, but did complain of chronic neuropathic pain.

CONCLUSION

NMOSD commonly coexist with other autoimmune diseases. The association of SS and NMOSD is well recognized. EBV infections can present with neurological manifestations however, EBV has also been linked to the development of autoimmunity. In our case, EBV was detected in CSF and antiviral therapy was initiated in addition to the treatment modalities for NMOSD which led to a full recovery in our patient.

Case of primary Sjogren's syndrome preceded by dystonia

There are only six cases in literature that describe development of dystonia with Sjogren's syndrome (SS). We describe a case of a 43-year-old woman who presented with symptoms including movement disorder, sensory neurogenic bladder, sensory loss and neuropathic pain, migraine like headaches, musculoskeletal pain, Raynaud's phenomenon and dysautonomia. Symptoms started in 2000, with weakness that progressed to dystonia in 2003. Diagnostic work-up was inconclusive with negative inflammatory serologies, cerebrospinal fluid and MRI for many years. After patient developed sicca syndrome with dry eyes and mouth in 2009, her rheumatoid factor titre was elevated (550 IU/mL), erythrocyte sedimentation rate, anti-Sjogrens syndrome-related antigen A (anti-Ro/SSA) and anti-SSB/La: anti-Sjogrens syndrome-related antigen B (anti-La/SSB) became positive. Lip biopsy confirmed diagnosis of SS. She was diagnosed with primary SS with neurological involvement. Her symptoms responded well to intravenous methylprednisolone. Symptoms stabilised with trials of immune-suppressive therapy. This is a case that demonstrates the delay of diagnosing SS with preceding unique neurological association.

Clinical features and risk factors of neurological involvement in Sjögren's syndrome

Background

To investigated distinct manifestations of Sjögren’s syndrome (SS) patients with neurological complications and the potential risk factors associated with neurological complications in SS, and to produce a disease evaluation and neurological involvement prediction for SS.

Methods

566 patients who fulfilled the 2002 classification criteria for SS from the Rheumatology Department of the First Affiliated Hospital of Wenzhou Medical University were included in the cross-sectional study. Clinical, immunological and histological characteristics were surveyed, and potential risk factors for neurological complications were examined by multivariate analysis.

Results

Among 566 SS patients, 184 (32.5%) patients had neurological involvement, with more than 10% got limbs pain, limbs numbness and cerebral infarction, respectively. Of these 184 SS patients with neurological complications, secondary SS (sSS) patients had a higher prevalence of peripheral nervous system (PNS) involvement than primary SS (pSS) patients (31.1 vs. 19%). And sSS patients showed higher total ESSPRI score and higher prevalence of xerostomia and low C3, C4 levels with more liver, articular involvement and saliva gland atrophy, and more severe lymphocyte infiltration in salivary glands than pSS patients. As for the specific factors associated with neurological involvement, low C3 level were found to be significant in pSS or sSS patients who were younger 50 year old, and ANA positivity, cardiac involvement, saliva gland atrophy were demonstrated to be associated in elder pSS patients. And xerophthalmia was found to be associated in sSS patients.

Conclusion

Low complement (C3) levels, xerophthalmia, ANA positive, cardiac involvement and labial salivary gland histological result were good ways to predict neurological complications in different subgroups of SS, which might provide insight into better clinical decision-making, especially at early stages of the disease.

Limbic Encephalitis Associated with Sjögren's Syndrome: Report of Three Cases

Sjögren's syndrome (SS) may be complicated by neurological manifestations. We herein report three women (age range 26-60 years old) who all presented with limbic encephalitis (LE) as the predominant clinical feature 3 months to 15 years after the diagnosis of SS. The 26-year-old patient also developed acute motor axonal neuropathy one week after autoimmune encephalitis. All three patients showed contrast-enhanced MRI lesions and inflammatory cerebrospinal fluid findings, while not displaying any anti-neuronal antibodies and showing a remarkable response to immunotherapy. SS is often overlooked when the symptoms are mild. Therefore, in LE cases with no identifiable cause, serological screening for rheumatologic disorders is recommended.

Use of a novel high-resolution magnetic resonance neurography protocol to detect abnormal dorsal root Ganglia in Sjögren patients with neuropathic pain: case series of 10 patients and review of the literature

The diagnosis and treatment of patients with Sjögren syndrome (SS) with neuropathic pain pose several challenges. Patients with SS may experience unorthodox patterns of burning pain not conforming to a traditional "stocking-and-glove" distribution, which can affect the face, torso, and proximal extremities. This distribution of neuropathic pain may reflect mechanisms targeting the proximal-most element of the peripheral nervous system-the dorsal root ganglia (DRG). Skin biopsy can diagnose such a small-fiber neuropathy and is a surrogate marker of DRG neuronal cell loss. However, SS patients have been reported who have similar patterns of proximal neuropathic pain, despite having normal skin biopsy studies. In such cases, DRGs may be targeted by mechanisms not associated with neuronal cell loss. Therefore, alternative approaches are warranted to help characterize abnormal DRGs in SS patients with proximal neuropathic pain.We performed a systematic review of the literature to define the frequency and spectrum of SS peripheral neuropathies, and to better understand the attribution of SS neuropathic pain to peripheral neuropathies. We found that the frequency of SS neuropathic pain exceeded the prevalence of peripheral neuropathies, and that painful peripheral neuropathies occurred less frequently than neuropathies not always associated with pain. We developed a novel magnetic resonance neurography (MRN) protocol to evaluate DRG abnormalities. Ten SS patients with proximal neuropathic pain were evaluated by this MRN protocol, as well as by punch skin biopsies evaluating for intraepidermal nerve fiber density (IENFD) of unmyelinated nerves. Five patients had radiographic evidence of DRG abnormalities. Patients with MRN DRG abnormalities had increased IENFD of unmyelinated nerves compared to patients without MRN DRG abnormalities (30.2 [interquartile range, 4.4] fibers/mm vs. 11.0 [4.1] fibers/mm, respectively; p = 0.03). Two of these 5 SS patients whose neuropathic pain resolved with intravenous immunoglobulin (IVIg) therapy had improvement of MRN DRG abnormalities.We have developed a novel MRN protocol that can detect DRG abnormalities in SS patients with neuropathic pain who do not have markers of peripheral neuropathy. We found that SS patients with MRN DRG abnormalities had statistically significant, increased IENFD on skin biopsy studies, which may suggest a relationship between trophic mediators and neuropathic pain. Given that our literature review has demonstrated that many SS neuropathic pain patients do not have a neuropathy, our findings suggest an important niche for this MRN DRG technique in the evaluation of broader subsets of SS neuropathic pain patients who may not have underlying neuropathies. The improvement of MRN DRG abnormalities in patients with IVIg-induced remission of neuropathic pain suggests that our MRN protocol may be capturing reversible, immune-mediated mechanisms targeting the DRG.

Neurological involvement in primary Sjögren syndrome: a focus on central nervous system

Objectives

Sjögren syndrome is an autoimmune disease involving mainly salivary and lacrimal glands. Beyond widely described PNS involvement, high variable prevalence of CNS manifestations ranging from 2.5 and 60% of all pSS patients has been reported, without specific syndrome definition. The aim of this cohort study was to evaluate the prevalence of CNS signs and symptoms in pSS patients and to identify possible biomarkers of CNS damage.

Methods

120 patients with pSS diagnosis according to the 2002 American-European Consensus Group criteria were enrolled after exclusion of secondary causes. All patients underwent to a wide neurological, neuropsychological, psychiatric, neuroradiological and ultrasonographic evaluation.

Results

Central and peripheral nervous system involvement was observed in 81 patients with a prevalence of 67.5%. The prevalence of CNS involvement was significantly higher than PNS disease (p 0.001). 68 patients (84%) shown non-focal CNS symptoms and 64 (79%) focal CNS deficits with headache as the most common feature (46.9%), followed by cognitive (44.4%) and mood disorders (38.3%). Particularly, we observed a high prevalence of migraine without aura, subcortical frontal executive functions and verbal memory impairment and apathy/alexythimia. MR spectroscopy revealed a reduction of NAA levels or NAA/Cr ratio decrease in subcortical frontal and basal ganglia white matter, while ultrasonography showed an impairment of microvasculature response. At multivariate analysis, headache, cognitive disorders and psychiatric symptoms was significantly associated to serological markers (anti-SSA), MRS and ultrasonographic features.

Conclusions

The higher prevalence of MWO-mimic headache, cognitive dys-esecutive syndrome and mood disorders observed in this series confirmed previous evidences of a higher diffused CNS compromission rather than focal involvement such as SM-like clinical course or NMO-like syndrome. The association with immunological biomarkers, metabolic cerebral dysfunction and microvascular damage suggests a possible endothelial dysfunction of the cerebral microcirculation or a potential inflammation-mediated shift of the neurovascular coupling.

Advances in the Aetiophatogenesis of Sjögren's Syndrome: a Literature Review

OBJECTIVES

The purpose of present paper is to review and critically address the recent advances on the aetiopathogenesis of the Sjögren's syndrome, taking into account the attained clinical features, with particular relevance given to the oral involvement.

MATERIAL AND METHODS

A comprehensive review of the available literature between 1970 and 2012, regarding to the aetiopathogenesis and clinical findings related to Sjögren's syndrome was conducted. Eligible studies were identified by searching the electronic literature PubMed, Medline, Embase, and ScienceDirect databases for relevant reports (last search update January 2012), combining the MESH heading term "Sjögren's syndrome", with the words "salivary glands, xerostomia, xerophtalmia, aetiology". The authors checked the references of the selected articles to identify additional eligible publications and contacted the authors, if necessary.

RESULTS

This article addresses a large number of the recent advances in the aetiopathogenesis of the disease, taking into account the attained clinical features of both local and systemic nature. Detailed mechanisms of the hypothesized influence of viral infections, genetic and hormonal factors, and the relevance of the altered glandular homeostasis are critically discussed with particular relevance given to the local and systemic involvement of Sjögren's syndrome.

CONCLUSIONS

The increasing number of data published recently on the aetiophatogenesis of Sjögren's syndrome strengthens the hypothesis that this condition, as all autoimmune diseases, is a multifactor disorder. Genetic predisposition, hormonal and environmental factors are thought to be implicated.

Sensory neuronopathy and autoimmune diseases

Sensory neuronopathies (SNs) are a specific subgroup of peripheral nervous system diseases characterized by primary degeneration of dorsal root ganglia and their projections. Multifocal sensory symptoms often associated to ataxia are the classical features of SN. Several different etiologies have been described for SNs, but immune-mediated damage plays a key role in most cases. SN may herald the onset of some systemic autoimmune diseases, which further emphasizes how important the recognition of SN is in clinical practice. We have thus reviewed available clinical, neurophysiological, and therapeutic data on autoimmune disease-related SN, namely, in patients with Sjögren's syndrome, autoimmune hepatitis, and celiac disease.

Immune mediated diseases and immune modulation in the neurocritical care unit

This chapter will review the spectrum of immune-mediated diseases that affect the nervous system and may result in an admission to the neurological intensive care unit. Immunomodulatory strategies to treat acute exacerbations of neurological diseases caused by aberrant immune responses are discussed, but strategies for long-term immunosuppression are not presented. The recommendations for therapeutic intervention are based on a synthesis of the literature, and include recommendations by the Cochrane Collaborative, the American Academy of Neurology, and other key organizations. References from recent publications are provided for the disorders and therapies in which randomized clinical trials and large evidenced-based reviews do not exist. The chapter concludes with a brief review of the mechanisms of action, dosing, and side effects of commonly used immunosuppressive strategies in the neurocritical care unit.

Peripheral nervous system manifestations of Sjögren syndrome: clinical patterns, diagnostic paradigms, etiopathogenesis, and therapeutic strategies

Sjögren syndrome is among the most common autoimmune diseases affecting adults in the United States, and is frequently regarded as an immune-mediated exocrinopathy exclusively causing dry eyes and dry mouth. However, as a systemic rheumatic disease, there can be various "extraglandular" complications. The eclectic permutation of peripheral nervous system (PNS) syndromes which occur in Sjögren patients are among the most common and severe extraglandular complications. This review article highlights the evaluation, differential diagnosis, immunopathogenic mechanisms, and potential treatment options of these PNS complications encountered by neurologists. The sensory neuropathies constitute the most frequent PNS complication. Sjögren patients can suffer from severe neuropathic pain, with small-fiber neuropathy causing lancinating or burning pain which can disproportionately affect the proximal torso or extremities, and the face (ie, in a "non-length-dependent distribution"). The technique of skin biopsy, assessing for the intraepidermal nerve fiber density of unmyelinated nerves, provides a useful technique for neurologists to diagnose small-fiber neuropathies, especially when there is such a non-length-dependent distribution. Other diagnostic techniques (ie, electromyography/nerve-conduction studies, evoked potentials, nerve and muscle biopsy) may be useful in specific subtypes of neuropathies. A rational approach to treatment requires a careful appraisal of the clinical subtype of the neuropathy, as well as a familiarity with such discriminating immunopathogenic mechanisms. The application of the traditional armamentarium used for neuropathic pain can be especially challenging. Sjögren patients can suffer from debilitating fatigue, sicca symptoms, and autonomic findings; as such manifestations can be complications of various neuropathic agents, neurologists should understand how to minimize such iatrogenic complications. Therefore, this article will empower neurologists to more effectively collaborate with rheumatologists, in the diagnosis and treatment of Sjögren patients with PNS complications.