Symptomatic and Electrodiagnostic Features of Peripheral Neuropathy in Scleroderma

Autoimmune polyneuropathies

The autoimmune peripheral neuropathies with prominent motor manifestations are a diverse collection of unusual peripheral neuropathies that are appreciated in vast clinical settings. This chapter highlights the most common immune-mediated, motor predominant neuropathies excluding acute, and chronic inflammatory demyelinating polyradiculoneuropathy (AIDP and CIDP, respectively). Other acquired demyelinating neuropathies such as distal CIDP and multifocal motor neuropathy will be covered. Additionally, the radiculoplexus neuropathies, resulting from microvasculitis-induced injury to nerve roots, plexuses, and nerves, including diabetic and nondiabetic lumbosacral radiculoplexus neuropathy and neuralgic amyotrophy (i.e., Parsonage-Turner syndrome), will be included. Finally, the motor predominant peripheral neuropathies encountered in association with rheumatological disease, particularly Sjögren's syndrome and rheumatoid arthritis, are covered. Early recognition of these distinct motor predominant autoimmune neuropathies and initiation of immunomodulatory and immunosuppressant treatment likely result in improved outcomes.

High-resolution ultrasound of peripheral neuropathies in rheumatological patients: An overview of clinical applications and imaging findings

Peripheral neuropathies are surprisingly common and can be associated with a number of conditions, including rheumatological diseases. Whether the co-existence of peripheral neuropathies with rheumatological disorders is coincidental or related to a common pathogenic mechanism, these disabling conditions can affect the outcome of rheumatological patients and should be targeted with specific treatment. The clinical presentation of peripheral neuropathy can be multifaceted and difficult to recognize in polysymptomatic patients. However, physicians adopting state-of-art diagnostic strategies, including nerve imaging, may improve the detection rate and management of neuropathies. In particular, a diagnostic approach relying exclusively on clinical history and nerve conduction studies may not be sufficient to disclose the etiology of the nerve damage and its anatomical location and thus requires integration with morphological studies. High-Resolution Ultrasound (HRUS) is increasingly adopted to support the diagnosis and follow-up of both joint disorders in rheumatology and peripheral neuropathies of different etiologies. In this review, the different types of nerve disorders associated with the most common syndromes of rheumatological interest are discussed, focusing on the distinctive sonographic features.

Clinical Manifestations, Pathogenesis, Diagnosis and Treatment of Peripheral Neuropathies in Connective Tissue Diseases: More Diverse and Frequent in Different Subtypes than Expected

Purpose of review: To discuss and summarize recent findings in peripheral neuropathy (PN) related to connective tissue diseases (CTD) including its prevalence, clinical manifestations, pathogenesis, diagnosis and treatment. Recent findings: Although PN is a common complication in CTD and has been well studied, recent research has shown that PN is more diverse and frequent in different subtypes of CTD than was expected. The incidence of PN in Sjögren’s syndrome and rheumatoid arthritis (RA) varies according to different disease subtypes, and the pathogenesis of neuropathic pain in different subtypes of eosinophilic granulomatosis with polyangiitis (EGPA) may also differ. Neurogenic inflammation, autoantibody-mediated changes, ischemia of the vascular wall and metabolic mechanisms have been shown to contribute to the pathogenesis of PN in CTD. Moreover, allergic inflammation has been recently identified as a possible new mechanism producing peripheral neuropathic pain associated with MPO-ANCA negative EGPA patients. Glucocorticoids are routinely used to relieve pain caused by PN. However, these steroids may cause hyperalgesia, exacerbate neuropathic pain, and activate the early phase of pain induction and produce hyperalgesia. Recently, neuroactive steroids, such as progesterone, tetrahydroprogesterone and testosterone, have been shown to exert protective effects for several PN symptoms, and in particular neuropathic pain. Neuroactive steroids will be an interesting topic for future research into PN in CTD. Summary: It is essential for the diagnosis and treatment of PN in CTD to be updated. Timely diagnosis, appropriate treatments, and multidisciplinary care are essential to minimize morbidity and decrease the risk of permanent neurologic deficits. Further studies are needed to guide diagnosis and treatment.

Epidemiology and treatment of peripheral neuropathy in systemic sclerosis

OBJECTIVE

The epidemiology and treatment of peripheral neuropathy in systemic sclerosis (SSc) is poorly understood. The objectives of this study were to evaluate the incidence, prevalence, risk factors, and treatments of peripheral neuropathy in SSc.

METHODS

A systematic review of Medline, Embase and CINAHL databases for literature reporting peripheral neuropathy in SSc was performed. Studies evaluating incidence, prevalence, risk factors, and treatments were synthesized. Meta-analysis using a random effects model was used to evaluate the prevalence of peripheral neuropathy.

RESULTS

113 studies reported 949 subjects with at least one type of peripheral neuropathy out of 2143 SSc patients studied. The mean age was 48.5 years. The mean time between SSc onset and detection of peripheral neuropathy was 8.85 years. The pooled prevalence of neuropathy was 27.4% (95%CI 22.4% - 32.7%). Risk factors for peripheral neuropathy in SSc included advanced diffuse disease, anticentromere antibodies, calcinosis cutis, ischemia of the vasa nervosum, iron deficiency anemia, metoclopramide, pembrolizumab, silicosis and uremia. There were 73 subjects with successful treatments (n=36 restoring sensation, n=37 restoring motor or sensorimotor function). Treatments included decompression surgery, prednisone, cyclophosphamide, carbamazepine, transcutaneous electrical nerve stimulation, tricyclic antidepressants and IVIG.

CONCLUSION

All-cause peripheral neuropathy is not uncommon in SSc. Compression neuropathies can be treated with decompression surgery. Observational data reporting immunosuppressive and anticonvulsants to treat peripheral neuropathy in SSc is limited and conflicting. This data provides the signal of effect to justify RCT to evaluate the efficacy of these interventions.

Immune Axonal Neuropathies Associated With Systemic Autoimmune Rheumatic Diseases

Immune axonal neuropathies are a particular group of immune-mediated neuropathies that occasionally accompany systemic autoimmune rheumatic diseases such as connective tissue dissorders and primary systemic vasculitides. Apart from vasculitis of vasa nervorum, various other mechanisms are involved in their pathogenesis, with possible therapeutic implications. Immune axonal neuropathies have highly heterogeneous clinical presentation and course, ranging from mild chronic distal sensorimotor polyneuropathy to severe subacute mononeuritis multiplex with rapid progression and constitutional symptoms such as fever, malaise, weight loss and night sweats, underpinning a vasculitic process. Sensory neuronopathy (ganglionopathy), small fiber neuropathy (sensory and/or autonomic), axonal variants of Guillain-Barré syndrome and cranial neuropathies have also been reported. In contrast to demyelinating neuropathies, immune axonal neuropathies show absent or reduced nerve amplitudes with normal latencies and conduction velocities on nerve conduction studies. Diagnosis and initiation of treatment are often delayed, leading to accumulating disability. Considering the lack of validated diagnostic criteria and evidence-based treatment protocols for immune axonal neuropathies, this review offers a comprehensive perspective on etiopathogenesis, clinical and paraclinical findings as well as therapy guidance for assisting the clinician in approaching these patients. High quality clinical research is required in order to provide indications and follow up rules for treatment in immune axonal neuropathies related to systemic autoimmune rheumatic diseases.

Rheumatologic Disorders and the Nervous System

PURPOSE

This article describes the neurologic manifestations of systemic autoimmune diseases.

RECENT FINDINGS

Systemic autoimmune diseases can be associated with a wide spectrum of neurologic comorbidities involving the central and peripheral nervous systems. Systemic lupus erythematosus (SLE) can be associated with a number of manifestations predominantly affecting the central nervous system (CNS), whereas peripheral neuropathy is less common. Sjögren syndrome can be associated with peripheral neuropathy in 10% of cases and CNS disease in 2% to 5% of cases. The risk of stroke is increased in SLE, rheumatoid arthritis, temporal arteritis, psoriatic arthritis, and ankylosing spondylitis. Systemic vasculitides present most commonly with mononeuritis multiplex but can also affect the CNS. Cognitive dysfunction is a common symptom among patients with systemic autoimmune diseases, most commonly seen in patients with SLE or Sjögren syndrome.

SUMMARY

Neurologic manifestations of systemic autoimmune disease are important to recognize, as they may often be the presenting manifestation leading to diagnosis of the systemic disease or may be associated with increased morbidity, other complications, or mortality. Timely diagnosis and institution of appropriate treatment, often requiring multidisciplinary care, is essential to minimize morbidity and decrease the risk of permanent neurologic deficits.

Large fiber peripheral neuropathy in systemic sclerosis: A prospective study using clinical and electrophysiological definition

AIM

The reported prevalence of peripheral neuropathy in systemic sclerosis (SSc) is variable between 0.01% to 28%, probably due to differences in sample size, study design and population. Our aim is to determine the prevalence of large fiber peripheral neuropathy in SSc and to identify any contributing factors.

METHOD

A prospective cross-sectional study of 60 SSc patients were evaluated for large fiber neuropathy using the modified clinical Total Neuropathy Score (cTNS) and nerve conduction study (NCS) of the upper and lower limbs. A combination of clinical (cTNS score ≥ 2) and NCS criteria (≥2 abnormal nerves including 1 sural [symmetrical polyneuropathy] and NCS abnormalities consistent with individual nerves/nerve roots [focal neuropathy]) was used to diagnose peripheral neuropathy.

RESULTS

The majority had limited cutaneous subset (75%). Mean age was 55.73 (SD ± 13.04) years and mean disease duration was 8.61 (SD ± 8.09) years. Twenty-two (36.7%) had combined clinical and NCS criteria for peripheral neuropathy, 14 (23.3%) with symmetrical polyneuropathy and 8 (13.3%) with focal neuropathy. Symmetrical polyneuropathy patients had significantly lower hemoglobin levels (11.2 vs. 12.35 g/L; P = .047). Serum vitamin B₁₂ levels were normal, therefore excluding vitamin B₁₂ deficiency. No other associations were found for both polyneuropathy and focal neuropathy with demography, co-morbid diseases and SSc disease factors such as Raynaud's phenomenon and modified Rodnan skin score.

CONCLUSION

Large fiber neuropathy is common in SSc patients, which could contribute to non-lethal burden in SSc with sensory loss and muscle weakness. Apart from lower hemoglobin in polyneuropathy, there were no associations with disease-specific features or co-morbid diseases.

Facial nerve palsy in giant-cell arteritis: case-based review

Acute peripheral facial nerve palsy is most frequently idiopathic (Bell's palsy) or virally induced, but can also be due to several other conditions. A rare cause is underlying systemic or autoimmune disease. A 79-year-old man presented with peripheral facial nerve palsy, malaise, and fever. Physical examination revealed tenderness of the left temporal artery and reduced pulsatility. ¹⁸F-FDG-PET/CT and biopsy of the temporal artery confirmed the diagnosis of giant cell arteritis (GCA). Prompt institution of corticosteroid therapy produced rapid decrease in inflammatory markers and gradual improvement of the facial nerve palsy. We searched the MEDLINE, Embase, and Scopus databases to identify previous reports of peripheral nerve palsy in GCA, other vasculitides, and autoimmune diseases. Facial nerve palsy as the presenting symptom of GCA has very rarely been reported. Although temporal artery biopsy is the gold standard for diagnosis, it may be negative in up to one-third of cases. In doubtful cases, imaging can help establish the diagnosis. Ultrasound, 3 T MRI, and ¹⁸F-FDG-PET/CT have all been previously reported to be useful. Peripheral facial nerve palsy may very rarely be the presenting symptom of GCA. Early correct diagnosis is essential for starting appropriate therapy. In patients with atypical features, ¹⁸F-FDG-PET/CT may be useful for establishing the diagnosis.

[Multiple mononeuropathy associated with systemic sclerosis with vasculitis confirmed by nerve biopsy: a case report]

A 68-year-old woman with a medical history of interstitial pneumonia associated with systemic sclerosis (SSc) presented with numbness of the lower limbs and left drop foot. She was diagnosed with multiple mononeuropathy based on the laterality of her symptoms, muscle weakness, thermal hypoalgesia, and nerve conduction study findings. Left sural nerve biopsy showed vasculitis, and steroid therapy was effective. This case highlights the importance of histopathological assessment to select an appropriate treatment strategy.

Immune Axonal Polyneuropathy

PURPOSE OF REVIEW

Immune axonal polyneuropathy is caused by a diverse group of disorders that share similar presentations and treatment regimens. This article focuses on the clinical findings, evaluation, and management of immune-mediated causes of axonal polyneuropathy, focusing primarily on large fiber sensorimotor polyneuropathy.

RECENT FINDINGS

Specific characteristics of an immune-mediated polyneuropathy have been incorporated in a new diagnostic screening tool that is highly sensitive and can easily be used in the outpatient clinic setting. New insights into autoantibodies may help identify the presence of an underlying autoimmune or paraneoplastic disease as the cause of a polyneuropathy.

SUMMARY

This article provides readers with further understanding into the autoimmune causes of axonal polyneuropathy and will help the clinician recognize key clinical features that may lead to timely diagnosis and treatment.

Neuropathic pain in Systemic Sclerosis patients: A cross-sectional study

OBJECTIVES

To investigate if patients with Systemic Sclerosis (SSc) show a higher prevalence of neuropathic pain (NP) in comparison with controls. To study the relationship between clinical variables of the disease and NP among SSc patients.

MATERIAL AND METHODS

48 patients and 45 controls were included. Presence of NP was assessed applying the DN4 "Douleur Neuropathique en 4 Questions" questionnaire. Different clinical variables were also assessed in patients. Statistical analysis included parametric, nonparametric tests and multivariate logistic regression.

RESULTS

NP was significantly higher in SSc patients (56.2% vs 13.3%, p<0.001). Mean Modified Rodnan Skin Score was independently associated with the presence of NP (p<0.05, OR 1.90).

CONCLUSIONS

Peripheral nervous system involvement in SSc is not well studied and, as far as the authors are aware, this is the first study published evaluating NP in SSc patients and controls. These findings should raise the awareness of the clinician to recognize and address the presence of NP in these patients, especially in those with severe skin involvement.