Primary Sjögren's Syndrome Associated Neuropathy

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.

Association of Sjögren's syndrome with myotonic dystrophy type 1

A 47-year-old woman presented with sicca symptoms, polyarthralgias, polymyalgias and dysphagia. She was found to have positive antinuclear, anti-SSA-Ro and anti-SSB-La antibodies. Slit lamp exam confirmed the presence of keratoconjunctivitis sicca, and the patient was diagnosed with Sjögren's syndrome. Three years later, she was referred for evaluation of gait instability associated with recent falls. On physical examination, the patient was found to have bilateral ptosis, percussion myotonia, distal upper and lower extremity weakness, and a steppage gait. Electromyography demonstrated electrical myotonia. Genetic testing revealed expanded CTG repeats (733 and 533) in the myotonic dystrophy type 1 (DM1) protein kinase gene, confirming the diagnosis of DM1. Dysphagia, pain and eye discomfort may occur in both Sjögren's syndrome and DM1, and in this case, may have delayed the diagnosis of muscular dystrophy.

Sjogren's Syndrome and TAM Receptors: A Possible Contribution to Disease Onset

Sjogren's syndrome (SS) is a chronic, progressive autoimmune disease featuring both organ-specific and systemic manifestations, the most frequent being dry mouth and dry eyes resulting from lymphocytic infiltration into the salivary and lacrimal glands. Like the related autoimmune disease systemic lupus erythematosus (SLE), SS patients and mouse models display accumulation of apoptotic cells and a Type I interferon (IFN) signature. Receptor tyrosine kinases (RTKs) of the Tyro3, Axl, and Mer (TAM) family are present on the surface of macrophages and dendritic cells and participate in phagocytosis of apoptotic cells (efferocytosis) and inhibition of Type I IFN signaling. This review examines the relationship between TAM receptor dysfunction and SS and explores the potential contributions of TAM defects on macrophages to SS development.

Diagnosis and management of sensory polyneuropathy

Sensory polyneuropathies, which are caused by dysfunction of peripheral sensory nerve fibers, are a heterogeneous group of disorders that range from the common diabetic neuropathy to the rare sensory neuronopathies. The presenting symptoms, acuity, time course, severity, and subsequent morbidity vary and depend on the type of fiber that is affected and the underlying cause. Damage to small thinly myelinated and unmyelinated nerve fibers results in neuropathic pain, whereas damage to large myelinated sensory afferents results in proprioceptive deficits and ataxia. The causes of these disorders are diverse and include metabolic, toxic, infectious, inflammatory, autoimmune, and genetic conditions. Idiopathic sensory polyneuropathies are common although they should be considered a diagnosis of exclusion. The diagnostic evaluation involves electrophysiologic testing including nerve conduction studies, histopathologic analysis of nerve tissue, serum studies, and sometimes autonomic testing and cerebrospinal fluid analysis. The treatment of these diseases depends on the underlying cause and may include immunotherapy, mitigation of risk factors, symptomatic treatment, and gene therapy, such as the recently developed RNA interference and antisense oligonucleotide therapies for transthyretin familial amyloid polyneuropathy. Many of these disorders have no directed treatment, in which case management remains symptomatic and supportive. More research is needed into the underlying pathophysiology of nerve damage in these polyneuropathies to guide advances in treatment.

Pain and fatigue in primary Sjögren's syndrome

Chronic fatigue, pain and depression are common in patients with primary Sjögren's syndrome. These phenomena mutually affect each other and have a considerable impact on the patients' quality of life. While pain is usually regarded as a fairly somatic phenomenon, both fatigue and depression have traditionally been regarded as more-or-less of psychological origin. There is an increasing understanding that this picture is multifaceted; that there is a genetic foundation, and that biological mechanisms regulate the clinical expression through activation of evolutionary, deeply conserved neuronal pathways in the brain. This pattern is evident not only in primary Sjögren's syndrome, but also in other systemic inflammatory autoimmune diseases, in cancer and in neurodegenerative diseases like Parkinson's disease. This article will mainly focus on the biology of pain and fatigue. We describe how these factors influence each other, and act with the overarching purpose of defending the organism against harm and danger.

Patterns of peripheral neuropathy in Sjogren's syndrome in a tertiary care hospital from South India

Introduction

Sjogren's syndrome (SS) is a systemic autoimmune disease that apart from involving the exocrine glands can affect any organ. Involvement of the peripheral nervous system results in a wide spectrum of neuropathic manifestations.

Objective

To evaluate the clinico-electrophysiological patterns as well as pathological characteristics of neuropathy in SS patients presenting to a neuromuscular clinic in a tertiary hospital from South India.

Materials and Methods

This is a retrospective study from the Departments of Neurology, Rheumatology, and Pathology from Nizam's Institute of Medical Sciences. Twenty-one patients with the diagnosis of SS and peripheral neuropathy, seen between 2010 and 2016 were analyzed. Clinical records, conventional nerve conduction studies, and lip and nerve biopsy reports were collected.

Results

Twenty one patients with SS had associated neuropathy. Female-to-male ratio was 2:1. In 14 (66.7%) patients, neuropathy was the initial manifestation, while in 4 (20%), exocrinopathy preceded neuropathy. The patterns of neuropathy included mononeuropathy multiplex (MNM) in 7 patients (30%), ganglionopathy in 4 (20%), length-dependant trigeminal autonomic neuropathy, and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in 2 (10%), and cranial neuropathy in 1 (10%). Eighteen (86%) were seropositive with either anti Ro/SS-A or anti La/SS-B antibodies. Schirmer's test was positive in 13 (61.9%) patients. Nerve biopsy showed vasculitis in 5 patients and demyelinating and axonopathy in 2 patients each.

Conclusions

We conclude that neuropathy is frequently the initial presentation of SS. MNM is the most common pattern followed by ganglionopathy. The pattern of neuropathy helps in arriving at the diagnosis of SS. Serology is a useful initial laboratory test. However,confirmation of SS is not by mere serology. Schirmer's test and lip biopsy are equally essential for the diagnosis, especially in seronegative patients when the clinical index of suspicion is high.

Sensory Neuronopathies

PURPOSE OF REVIEW

The sensory neuronopathies are sensory-predominant polyneuropathies that result from damage to the dorsal root and trigeminal sensory ganglia. This review explores the various causes of acquired sensory neuronopathies, the approach to diagnosis, and treatment.

RECENT FINDINGS

Diagnostic criteria have recently been published and validated to allow differentiation of sensory neuronopathies from other polyneuropathies. On the basis of serial electrodiagnostic studies, the treatment window for the acquired sensory neuronopathies has been identified as approximately 8 months. If treatment is initiated within 2 months of symptom onset, there is a better opportunity for improvement of the patient's condition. Even though sensory neuronopathies are rare, significant progress has been made regarding characterization of their clinical, electrophysiologic, and imaging features. This does not hold true, however, for treatment. There have been no randomized controlled clinical trials to guide management of these diseases, and a standard treatment approach remains undetermined.

Magnetic Resonance Imaging of the Digital Nerves of the Hand: Anatomy and Spectrum of Pathology

Digital nerves are intrinsic to the sensory and motor function of the hand. These nerves represent the terminal ramifications of the ulnar, median, and radial nerves and are located distal to the carpal tunnel and Guyon canal. With magnetic resonance imaging, traumatic and nontraumatic abnormalities of the digital nerves can be shown with high contrast as well as high spatial resolution. Digital nerve abnormalities are most commonly posttraumatic in nature; however, infection, inflammatory, vascular malformations, and neoplasms can rarely occur. Magnetic resonance imaging is playing an increasing role in the assessment of peripheral nerve injury throughout the body, and in the hand, which can accurately identify the extent and character of digital nerve abnormalities before operative intervention.

Cognition, depression, fatigue, and quality of life in primary Sjögren's syndrome: correlations

OBJECTIVE

The aim of the present study was to investigate the prevalence and pattern of cognitive dysfunction observed in primary Sjögren's syndrome (PSS) and to examine the relationships between cognitive abilities, depression, fatigue, and quality of life.

MATERIALS AND METHODS

Thirty-two subjects with PSS were compared with 19 healthy controls on comprehensive neuropsychological, depression, fatigue, health state, and daily-life activities tests.

RESULTS

There was low performance in Clock Drawing, COWAT, Paced Auditory Serial Addition Test (PASAT), Colorless Word Reading (Stroop1) and Recognizing Colors (Stroop2) Patterns of STROOP test, SDLT, Auditory-Verbal Learning Test (AVLT), immediate and long-term verbal memory, Benton Judgment of Line Orientation Test (BJLOT), and in all the patterns of RCFT in PSS patients compared to the healthy control group (p < .05). It was observed an increased depression frequency and fatigue severity, impairment in health condition, and a decreased quality of life in PSS cases compared to the healthy controls (p < .05). All the depression, fatigue severity, and quality of life tests showed a significant positive correlation with each other (p < .05). A significant negative correlation between Clock Drawing and SF-36-BP (p = .031, r = -.382) and SF-36-GH (p = .027, r = -.392) was observed.

CONCLUSIONS

Clock Drawing, PASAT, and AVLT are very useful tests to determine the subclinical and clinical cognitive dysfunction to evaluate attention, information processing speed, executive functions, and short-term and long-term verbal memory in PSS patients. Depression and fatigue may not affect the neuropsychological tests performance.

[A case of chronic progressive motor-dominant multiple mononeuritis associated with primary Sjögren's syndrome]

A 45-year-old female with a history of dry eyes presented with chronic progressive disturbance of her right finger extension, bilateral foot drops, and dysesthesia in the left lower leg. On admission, neurological examination revealed decreased tendon reflex in the right upper limb and bilateral lower limbs, and dysesthesia in the distal outer portions of the bilateral lower legs. Her vibration sensation was moderately diminished in both lower legs. Weakness ranging from moderate to severe was predominantly found in the muscles innervated by the radial (r > l), medial (r > l), ulnar (r > l), deep peroneal (r ≒ l), tibial (r < l), and medial planter nerves (r < l). Nerve conduction study showed asymmetrical axonal neuropathy, while chronic neurogenic changes were observed on needle electromyography. Cerebrospinal fluid analysis results were unremarkable, except for an elevated IgG index (1.53) and the presence of oligoclonal IgG bands. Seropositive anti-SS-A antibody and histological findings of the biopsied minor salivary gland, as well as the lack of other connective tissue disorders, indicated primary Sjögren syndrome (SjS). A left sural nerve biopsy showed inhomogeneous reductions in the myelinated fibers within fascicules, mild infiltration of CD8-positive T lymphocytes around small vessels, and no fibrinoid necrosis in the arteries. From these findings, the diagnosis of motor-dominant multiple mononeuritis associated with primary SjS was made. Therapy that comprised a single course of intravenous (IV) methylprednisolone (1 g for 3 days), followed by oral prednisolone (60 mg/day) with gradual tapering, resulted in no amelioration of her symptoms. She then received IV immunoglobulin (0.4 mg/kg/day for 5 days), which resulted in moderate improvement in the strength of several muscles and a reduction of CSF IgG index (0.89). A wide variety of peripheral nerve complications are documented in primary SjS. However, the present case is unique in the symptoms of chronic progressive, motor-dominant, multiple mononeuritic phenotype.

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.

The cutaneous nerve biopsy: technical aspects, indications, and contribution

Skin biopsy with a 3mm disposable circular punch is easy to perform and allows, after proper processing, the visualization of epidermal, dermal, and sweat gland nerve fibers. A technique of sampling the epidermis alone by applying a suction capsule, the "blister" technique, has also been developed. It is most common to stain immunohistochemically for the pan-axonal marker protein gene product 9.5 (PGP 9.5), an ubiquitin C-terminal hydroxylase. The sections are then observed and analyzed with bright-field microscopy or with indirect immunofluorescence with or without confocal microscopy. Most studies report quantification of intraepidermal nerve fiber density displayed in bright-field microscopy. Normative values have been established, particularly from the distal part of the leg, 10cm above the external malleolus. In diabetes mellitus early degeneration of intraepidermal nerve fibers is induced and there is slower regeneration even when there is no evidence of neuropathy. Skin biopsy is of particular value in the diagnosis of small fiber neuropathy when nerve conduction studies are normal. It may also be repeated in order to study the progressive nature of the disease and also has the potential of studying regeneration of nerve fibers and thus the effects of treatment. Inflammatory demyelinating neuropathies may also involve loss of small-diameter nerve fibers and IgM deposits in dermal myelinated nerve fibers in anti-MAG neuropathy. In some cases the presence of vasculitis in skin may indicate a nonsystemic vasculitic neuropathy and in HIV neuropathy intraepidermal nerve fiber density is reduced in a length-dependent manner. In several hereditary neuropathies intraepidermal nerve fiber density may be reduced but other abnormalities can also be demonstrated in dermal myelinated fibers. Some small swellings and varicosities may be present in the distal leg skin biopsy of healthy individuals but large axonal swellings are considered as evidence of a pathological process affecting the normal structure of nerves. The indirect immunofluorescence technique with confocal microscopy provides the opportunity to study the complex structure of sensory receptors and cutaneous myelinated fibers and the innervation of sweat glands, arrector pilorum muscles, and vessels.

Intravenous Immunoglobulin and Mycophenolate Mofetil for Long-Standing Sensory Neuronopathy in Sjögren's Syndrome

Sensory neuronopathy is described in association with the Sjögren's syndrome (SS). We studied a 55-year-old woman with a 4-year history of progressive asymmetric numbness, distal tingling, and burning sensation in upper and lower limbs. In a few months, she developed ataxia with increased hypoanaesthesia. Electrodiagnostic tests revealed undetectable distal and proximal sensory nerve action potential in upper and lower limbs. Cervical spine magnetic resonance showed a signal hyperintensity of posterior columns. Previous treatment with high-dose glucocorticoids and azathioprine was ineffective. A combined treatment with intravenous immunoglobulin and mycophenolate mofetil was followed by a progressive and persistent improvement. This case documented the efficacy and the safety of the coadministration of intravenous immunoglobulin and mycophenolate mofetil in sensory neuronopathy associated with SS refractory to conventional immunosuppressive therapy.

Acute and chronic polyradiculopathies

Polyradiculopathies are uncommon peripheral nervous system syndromes that result from a variety of conditions. The clinical manifestations are variable but often include symmetric or asymmetric distal and proximal weakness with a variable degree of sensory loss and reduction or loss of reflexes. The most common cause of an acute polyradiculopathy is acute inflammatory demyelinating polyradiculopathy (also known as Guillain-Barré syndrome); however, other inflammatory, infectious, or neoplastic causes can present with similar features. Chronic polyradiculopathies include chronic inflammatory demyelinating polyradiculopathy as well as paraprotein-related syndromes and other inflammatory and infectious causes. Evaluation using a combination of serologic studies, electrodiagnostic testing, and CSF evaluation can help to identify the underlying etiology and implement the appropriate treatment. This article reviews the approach to patients with suspected polyradiculopathy and the features of the more common causes of acute and chronic polyradiculopathies.

Psychiatric manifestations in patients with dysautonomy associated with systemic lupus erythematosus

The psychiatric manifestations of three patients with systemic lupus erythematosus (SLE) and neuropathic dysautonomic processes are described. All patients had a severe form of SLE with neurological, renal, articular, pulmonary or haematological manifestations. All three have two types of psychiatric manifestations: (1) a chronic and progressive depression and (2) a complex dissociative disorder during the acute episodes of postural hypotension. A provocative test with SPECT with 99mTc-HmPAO to be done during the episode of orthostatic hypotension may contribute to clinical assessment of complex changes in cerebral regional perfusion.

Fatigue and depression predict physician visits and work disability in women with primary Sjögren's syndrome: results from a cohort study

OBJECTIVES

Patients with primary SS (pSS) are frequently suffering from multiple enduring disorders that raise the risk of work disability and require treatment by various health-care specialists. We aimed at determining predictors of physician visits and work disability in pSS patients.

METHODS

Physician visits within the past 6 months, employment status and sick leave were compared among 176 female pSS patients and 115 age-matched controls. Dryness, pain, fatigue and depression were assessed by rating scales of the EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI), the Profile of Fatigue and Discomfort (PROFAD) and Patient Health Questionnaire depression measurements (PHQ-9). Factors associated with an increased number of physician visits and inability to work were determined by multivariate logistic regression analysis.

RESULTS

Patients and controls were comparable in age and education, but differed significantly in the prevalence of depression (38.1 vs 7.9%, P < 0.001), the number of physician visits [17.0 (10.0) vs 6.5 (4.5); P < 0.001] and gainful employment (≤64 years: 52.8 vs 77.1% P < 0.001). Multivariate regression analyses revealed that depression (PHQ-9) and/or fatigue, particularly lack of stamina, but not dryness, were significantly associated with physician visits and working status in pSS patients. Patients with high ratings for the statement 'I have had difficulties to keep going, was easily worn out or lacking in energy' had a highly increased risk of not being gainfully employed (adjusted OR 4.1; 95% CI 1.5, 11.2; P < 0.001).

CONCLUSION

In pSS, lack of stamina and/or depression cause a higher level of individual and societal burden than dry eyes and mouth. Fatigue and depression deserve more recognition as treatment targets in pSS.

Dysfunction of lacrimal and salivary glands in Sjögren's syndrome: nonimmunologic injury in preinflammatory phase and mouse model

Sjögren's syndrome (SjS) is a chronic autoimmune disorder characterized by dry eyes and dry mouth due to dacryoadenitis and sialoadenitis with SS-A/Ro and/or SS-B/La autoantibodies in genetically predisposed individuals. Destruction of lacrimal and salivary glands by autoimmune reactions may lead to clinical manifestation. However, the mechanisms behind the decreased volume of secretions in tears and saliva are complex and are not fully understood. Exocrine gland dysfunction may precede autoimmunity (acquired immunity) or represent a process independent from inflammation in the pathogenesis of SjS. The preceded functional and morphologic changes of those tissues by nonimmunologic injury before the development of inflammation at the sites of target organs have been implicated. This paper focuses on the several factors and components relating to glandular dysfunction and morphologic changes by nonimmunologic injury during the preinflammatory phase in mouse model, including the factors which link between innate immunity and adaptive immunity.

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.

Lupoid sclerosis

Lupoid sclerosis (LS) is a controversial entity, comprising features of both systemic lupus erythematosus and multiple sclerosis. Diagnostic criteria are a matter of debate, as well as the role of antinuclear and antiphospholipid antibodies. In this review, clinical and laboratory findings of LS available on Pubmed up to date are discussed.