The nervous system in systemic sclerosis (scleroderma). Clinical features and pathogenetic mechanisms

Neurological, cardiac, musculoskeletal, and renal manifestations of scleroderma along with insights into its genetics, pathophysiology, diagnostic, and therapeutic updates

Background

Scleroderma, also referred to as systemic sclerosis, is a multifaceted autoimmune condition characterized by abnormal fibrosis and impaired vascular function. Pathologically, it encompasses the persistent presence of inflammation, abnormal collagen buildup, and restructuring of blood vessels in various organs, resulting in a wide range of clinical symptoms. This review incorporates the most recent scientific literature on scleroderma, with a particular emphasis on its pathophysiology, clinical manifestations, diagnostic approaches, and treatment options.

Methodology

A comprehensive investigation was carried out on numerous databases, such as PubMed, MEDLINE, Scopus, Web of Science, and Google Scholar, to collect pertinent studies covering diverse facets of scleroderma research.

Results

Scleroderma presents with a range of systemic manifestations, such as interstitial lung disease, gastrointestinal dysmotility, Raynaud's phenomenon, pulmonary arterial hypertension, renal complications, neurological symptoms, and cardiac abnormalities. Serological markers, such as antinuclear antibodies, anti-centromere antibodies, and anti-topoisomerase antibodies, are important for classifying diseases and predicting their outcomes.

Discussion

The precise identification of scleroderma is crucial for promptly and correctly implementing effective treatment plans. Treatment approaches aim to improve symptoms, reduce complications, and slow down the progression of the disease. An integrated approach that combines pharmacological agents, including immunosuppressants, endothelin receptor antagonists, and prostanoids, with nonpharmacological interventions such as physical and occupational therapy is essential for maximizing patient care.

Conclusion

Through the clarification of existing gaps in knowledge and identification of emerging trends, our goal is to improve the accuracy of diagnosis, enhance the effectiveness of therapeutic interventions, and ultimately enhance the overall quality of life for individuals suffering from scleroderma. Ongoing cooperation and creative research are necessary to advance the field and achieve improved patient outcomes and new therapeutic discoveries.

Ocular Involvement in Systemic Sclerosis: Updated Review and New Insights on Microvascular Impairment

Systemic sclerosis (SSc) is a chronic multisystemic disease characterized by immunological activation, diffuse vasculopathy, and generalized fibrosis exhibiting a variety of symptoms. A recognized precursor of SSc is Raynaud's phenomenon, which is part of the very early disease of systemic sclerosis (VEDOSS) in combination with nailfold videocapillaroscopy (NVC) impairment. The pathophysiology of ocular involvement, alterations in internal organs, and body integumentary system involvement in SSc patients are complicated and poorly understood, with multiple mechanisms presumptively working together. The most prevalent ocular symptoms of SSc are abnormalities of the eyelids and conjunctiva as well as dry eye syndrome, due to fibroblasts' dysfunction and inflammation of the ocular surface. In particular, lagophthalmos, blepharophimosis limitation of eyelid motion, eyelid telangiectasia, and rigidity or tightening of the lids may affect up to two-third of the patients. In addition, reduction in central corneal thickness, iris defects and higher rates of glaucoma were reported. In the first reports based on retinography or fluorescein angiography, about 50% of SSc patients showed signs of vascular disease: peripheral artery occlusion, thinning of retinal pigment epithelium and choroidal capillaries, ischemic areas surrounded by intraretinal extravasation and microaneurysms, and peripheral capillary non-perfusion. Successively, thanks to the advent of optical coherence tomography angiography (OCTA), several studies highlighted significant impairment of either the choriocapillaris and retinal vascular plexuses, also correlating with NVC involvement and skin disease, even in VEDOSS disease. Given the sensitivity of this technique, ocular micro-vasculopathy may act as a tool for early SSc identification and discriminate between disease stages.

Transcutaneous auricular branch vagal nerve stimulation as a non-invasive add-on therapeutic approach for pain in systemic sclerosis

OBJECTIVE

Systemic sclerosis (SSc) is an autoimmune disease with health-related quality of life (HRQoL) high impairment. Pain is of paramount importance to be targeted by therapeutical approaches. Our study aim was to perform an add-on device-based non-invasive neuromodulatory treatment through transcutaneous auricular vagal nerve stimulation (tVNS) in patients with SSc, assessing its effects on pain as primary endpoint and on inflammation, cardiovascular autonomic control and HRQoL.

METHODS

Thirty-two patients with SSc were enrolled based on reported pain assessed through Numeric Rating Scale (NRS). Twenty-one (90% with limited cutaneous SSc) completed a randomised, cross-over, patient-blind trial, in which interventional and active control were used in random order for 4 weeks, interspersed with 4 weeks washout. NRS, Patient-Reported Outcomes Measurement Information System-29 (PROMIS-29) Item4 for pain interference, heart rate variability (HRV), serum cytokines and HRQoL questionnaires (Health Assessment Questionnaire, Patient Health Questionnaire-9, University of California, Los Angeles Gastrointestinal Tract, Pittsburgh Sleep Quality Index) were assessed at baseline, at T1 (after 1 month of tVNS or active control), at T2 (after washout) and at T3 (after 1 month of active control or tVNS). T-test for paired data and Wilcoxon signed-rank test for non-normally distributed parameters were performed to compare the effect of tVNS and active control.

RESULTS

NRS pain was significantly reduced by tVNS and not by active control (Mean±SD: -27.7%±21.3% vs -7.7%±26.3%, p=0.002). Interleukin-6 was downregulated in tVNS versus active control (p=0.029). No significant differences were observed in tVNS versus active control for PROMIS-29 Item4, QoL scales and HRV with both spectral and symbolic analyses.

CONCLUSION

tVNS demonstrated to be a safe and non-invasive add-on tool to reduce pain in SSc.

The Interplay between Autonomic Nervous System and Inflammation across Systemic Autoimmune Diseases

The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation.

Autonomic nervous system dysfunction correlates with microvascular damage in systemic sclerosis patients

OBJECTIVES

Cardiac autonomic neuropathy is among the known cardiovascular complications of systemic sclerosis and may affect the whole prognosis of the disease. The aim of our study was to assess cardiac autonomic neuropathy prevalence in our cohort of systemic sclerosis patients and compare its main features with clinical and epidemiological data, particularly with the severity of microvascular damage, as detected by nailfold videocapillaroscopy.

METHODS

Twenty-six patients with definite systemic sclerosis were consecutively enrolled at our outpatient rheumatology clinic. All patients underwent physical examination, nailfold videocapillaroscopy, and autonomic neuropathy diagnostic tests (orthostatic hypotension test, deep breathing test, lying-to-standing, and Valsalva maneuvers).

RESULTS

Cardiac autonomic neuropathy prevalence was 50% (13 cases). On univariate analysis, cardiac autonomic neuropathy was shown to be significantly associated with an active pattern on nailfold videocapillaroscopy (odds ratio 5.86, 95% confidence interval 1.59-9.24; p = 0.032), whereas anti-Scl-70 positivity (odds ratio, 0.24; 95% confidence interval, 0.03-2.12; p = 0.049) and C-reactive protein (odds ratio, 19.32; 95% confidence interval, 1.79-56.71; p = 0.036) reached only a borderline statistical association. The time-dependent Cox multivariate regression model showed cardiac autonomic neuropathy development to be independently associated with an active pattern on nailfold videocapillaroscopy (odds ratio, 7.19; 95% confidence interval, 1.87-8.96; p = 0.042) and anti-Scl-70 positivity (odds ratio, 5.92; 95% confidence interval, 1.06-18.43; p = 0.048).

CONCLUSIONS

Severe microvascular damage, as detected by nailfold videocapillaroscopy, may suggest the coexistence of autonomic dysfunction and should be considered as a red flag for the identification of patients particularly at risk of cardiac morbidity and mortality.

Diseases which cause generalized peripheral neuropathy: a systematic review

PURPOSE

Peripheral autonomic neuropathy, including enteric neuropathy, may be subtle and unrecognized for several years. Diagnosis of enteric neuropathy demands complicated examinations such as full-thickness bowel biopsy. We hypothesized that knowledge about simultaneous occurrence of different types of neuropathy would lead to faster recognition and diagnosis of autonomic/enteric neuropathy. The aim of the present systematic review was to increase the awareness of disease groups causing autonomic and enteric neuropathy along with sensorimotor neuropathy.

METHODS

A systematic search strategy was used in PubMed, Embase and Web of Science. First, 4978 articles were identified. Review of titles/abstracts rendered exclusion of animal studies, articles not written in English or full-length, case reports, conference abstracts and duplicates until 357 articles remained. The full-length evaluation resulted in 35 studies (27 non-systematic reviews) which described objectively verified peripheral autonomic, enteric and sensorimotor neuropathy within the same disease.

RESULTS

Diabetes is the most common disease in society rendering generalized peripheral neuropathy. Accumulation of tissue deposits in amyloidosis, Lewy body disorders and sarcoidosis lead to widespread peripheral neuropathy. Several autoimmune disorders such as systemic sclerosis and primary Sjögren's syndrome present themselves with neuropathy. Paraneoplastic neuropathy may appear prior to symptoms from the malignancy. Both the infection per se, as well as the autoimmune response to the infection, i.e., Guillain-Barré syndrome, may lead to widespread peripheral neuropathy. Hereditary disorders with disturbed metabolism lead to intermittent attacks of neuropathy.

CONCLUSIONS

The major causes of generalized peripheral neuropathy are diabetes, diseases with tissue deposits, autoimmunity, infections, malignancy and metabolic diseases.

Genome-Wide Reduction in Chromatin Accessibility and Unique Transcription Factor Footprints in Endothelial Cells and Fibroblasts in Scleroderma Skin

OBJECTIVE

Systemic sclerosis (SSc) is characterized by widespread fibrosis and vascular complications. This study was undertaken to examine the chromatin landscape and transcription factor footprints in SSc, using an assay for genome-wide chromatin accessibility.

METHODS

Dermal endothelial cells (ECs) and fibroblasts were isolated from healthy controls and patients with diffuse cutaneous SSc (dcSSc). Assay for transposase-accessible chromatin with sequencing (ATAC-seq) was performed to assess genome-wide chromatin accessibility at a read depth of ~150 million reads per sample. Transcription factor footprinting and motif binding analysis were performed, followed by functional experiments.

RESULTS

Chromatin accessibility was significantly reduced in dcSSc patients compared to healthy controls. Differentially accessible chromatin loci were enriched in pathways and gene ontologies involved in the nervous system, cell membrane projections and cilia motility, nuclear and steroid receptors, and nitric oxide. In addition, chromatin binding of transcription factors SNAI2, ETV2, and ELF1 was significantly increased in dcSSc ECs, while recruitment of RUNX1 and RUNX2 was enriched in dcSSc fibroblasts. We found significant down-regulation of the neuronal gene NRXN1 and up-regulation of SNAI2 and ETV2 in dcSSc ECs. In dcSSc fibroblasts, down-regulation of the neuronal gene ENTPD1 and up-regulation of RUNX2 were confirmed. Further functional analysis revealed that ETV2 and NRXN1 dysregulation affected angiogenesis in ECs, while ENTPD1 enhanced profibrotic properties in dcSSc fibroblasts.

CONCLUSION

Our data identify the chromatin blueprint of dcSSc, and suggest that neuronal-related characteristics of SSc ECs and fibroblasts could be a culprit for dysregulated angiogenesis and enhanced fibrosis. Targeting the key pathways and transcription factors identified might present novel therapeutic approaches in SSc.

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.

Ocular manifestations in patients with systemic sclerosis

Systemic sclerosis (SSc) is a rare, chronic autoimmune disease with unknown etiology. Its prominent features are fibrosis, vasculopathy and impaired immune response. Disease can also affect eyes leading to various findings in ophthalmological examination.

The objective of this study was to determine the prevalence and type of ocular involvement in patients with SSc. A systematic literature review was conducted using electronic databases. A combination of following keywords was used: “systemic sclerosis” and ophthalmology-related search terms, including the keywords “eye”, “ocular” and “ophthalmic”.

In conclusion, eyelid and conjunctival abnormalities and dry eye disease are among the most common ocular manifestations of SSc. Their diversity is connected to complexity of the disease.

Ganglionic Acetylcholine Receptor Antibodies and Autonomic Dysfunction in Autoimmune Rheumatic Diseases

Autonomic neuropathy has been reported in autoimmune rheumatic diseases (ARD) including Sjögren’s syndrome, systemic sclerosis, rheumatoid arthritis, and systemic lupus erythematosus. However, the pathophysiological mechanism underlying autonomic dysfunction remains unknown to researchers. On the other hand, autoimmune autonomic ganglionopathy (AAG) is an acquired immune-mediated disorder, which causes dysautonomia that is mediated by autoantibodies against ganglionic acetylcholine receptors (gAChRs). The purpose of this review was to describe the characteristics of autonomic disturbance through previous case reports and the functional tests used in these studies and address the importance of anti-gAChR antibodies. We have established luciferase immunoprecipitation systems to detect antibodies against gAChR in the past and determined the prevalence of gAChR antibodies in various autoimmune diseases including AAG and rheumatic diseases. Autonomic dysfunction, which affects lower parasympathetic and higher sympathetic activity, is usually observed in ARD. The anti-gAChR antibodies may play a crucial role in autonomic dysfunction observed in ARD. Further studies are necessary to determine whether anti-gAChR antibody levels are correlated with the severity of autonomic dysfunction in ARD.

Evaluation of brain changes in systemic sclerosis (SSc) patients using two different techniques of MRI: Is it really worthy?

BACKGROUND

Systemic sclerosis (SSc) is a rare chronic multi-system autoimmune disease of unknown cause and a complex pathogenesis. The hallmark of the disease is microvascular vasculopathy which results in tissue ischemia with recurrent episodes of reperfusion. Diffusion-weighted (DW) Magnetic Resonance imaging (MRI) is an excellent tool for the detection of activity of any vascular or inflammatory lesions.

OBJECTIVES

Detect brain changes in systemic sclerosis patients with asymptomatic CNS manifestations using fluid attenuation inversion recovery (FLAIR) weighted sequence and diffusion-weighted (DW) sequence MRI.

METHODS

Fifteen systemic sclerosis female patients aged 27-60 years old with disease duration of 1-20 years with no CNS clinical manifestations were included. A controlled group of 14 clinically normal persons, age and sex matched. Both groups were subjected to brain MR examination at 1.5T; a FLAIR weighted sequence and a DW sequence. SPSS (version 20) was used for statistical analysis.

RESULTS

37 white matter hyperintense lesions (≤2 to ≥ 5mm in diameter) were detected in patient group using FLAIR weighted MRI while diffusion-weighted MRI failed to detect the same lesions. A non-significant relation (P=.259) between the presence of white matter hyperintense lesions and the severity of peripheral vascular affection of the disease was observed.

CONCLUSIONS

Asymptomatic central nervous system vasculopathy is detected in systemic sclerosis using FLAIR MRI, while diffusion MRI failed to detect such lesions. These findings suggest a non-inflammatory form of central nervous system microvasculopathy in SSc patients.

Neurosonological and cognitive screening for evaluation of systemic sclerosis patients

OBJECTIVE

Assessment of cerebrovascular hemodynamics, third ventricle diameter (as a proxy of brain atrophy) by transcranial sonography (TCS), and screening of cognitive performance by the Symbol Digit Modalities Test (SDMT) in systemic sclerosis (SSc) patients.

METHODS

A total of 38 SSc patients recruited from the outpatient clinic of the Rheumatology Department, Kasr Alainy Hospital, Cairo University, and 51, age- and sex-matched, healthy controls were included in the study. TCS was used to assess the mean flow velocity (MFV), pulsatility index (PI) of the anterior, middle, and posterior cerebral arteries bilaterally, and to measure the third ventricle diameter as a proxy of brain atrophy. Cognitive impairment was screened using the SDMT. p values < 0.05 were considered statistically significant.

RESULTS

There was no significant difference between SSc patients and controls regarding either PI or MFV of the anterior, middle, and posterior cerebral arteries; also, there was no difference regarding the third ventricle diameter; however, limited SSc patients showed a significant increase in the PI of PCA and MFV of ACA as compared with diffuse SSc patients (p = 0.005, 0.004). There was a significant difference between SSc patients and controls regarding the SDMT (p = 0.016).

CONCLUSION

There is an evidence of increased cerebral vascular tone and resistance in limited SSc patients compared with diffuse SSc subgroup, without evidence of cerebral atrophy, suggesting early cerebrovascular affection even in asymptomatic limited SSc patients. There was also an evidence of cognitive impairment in SSc patients.

Symptoms of Autonomic Dysfunction in Systemic Sclerosis Assessed by the COMPASS-31 Questionnaire

OBJECTIVE

Autonomic dysfunction is a known complication of systemic sclerosis (SSc) that can affect vascular tone, gastrointestinal (GI) motility, heart rate, and blood pressure control. We sought to quantify autonomic symptom burden in SSc, and to define the characteristics of patients with SSc and autonomic dysfunction.

METHODS

Patients with SSc were consecutively recruited during routine clinical visits at the Johns Hopkins Scleroderma Center and asked to complete the Composite Autonomic Symptom Score (COMPASS)-31 questionnaire, a validated tool to assess symptoms of autonomic dysfunction. We determined the relationship between various clinical and serological features of SSc and the total COMPASS-31 scores and domain-specific scores using the Student t test or Wilcoxon rank-sum test for dichotomous variables and linear regression analysis for continuous variables.

RESULTS

The study included 104 patients with SSc who completed the COMPASS-31 questionnaire. The mean COMPASS-31 score in this cohort was 24.9 ± 15.5, higher than COMPASS-31 scores from previously published healthy controls (8.9 ± 8.7). Compared to patients with mild or absent GI disease, patients with significant GI disease had higher scores across several subdomains of the COMPASS-31, including orthostatic intolerance (median 10.0 vs 0, p = 0.006) and secretomotor dysfunction (median 6.4 vs 4.3, p = 0.03). There was also a dose-response relationship between GI disease severity and autonomic symptom burden.

CONCLUSION

Symptoms of autonomic dysfunction are common in SSc. Patients with more severe GI disease in SSc report more symptoms of dysautonomia across many facets of the autonomic nervous system.

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.

Neurologic involvement in scleroderma: a systematic review

OBJECTIVES

To perform a systematic review of neurologic involvement in Systemic sclerosis (SSc) and Localized Scleroderma (LS), describing clinical features, neuroimaging, and treatment.

METHODS

We performed a literature search in PubMed using the following MeSH terms, scleroderma, systemic sclerosis, localized scleroderma, localized scleroderma "en coup de sabre", Parry-Romberg syndrome, cognitive impairment, memory, seizures, epilepsy, headache, depression, anxiety, mood disorders, Center for Epidemiologic Studies Depression (CES-D), SF-36, Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Patient Health Questionnaire-9 (PHQ-9), neuropsychiatric, psychosis, neurologic involvement, neuropathy, peripheral nerves, cranial nerves, carpal tunnel syndrome, ulnar entrapment, tarsal tunnel syndrome, mononeuropathy, polyneuropathy, radiculopathy, myelopathy, autonomic nervous system, nervous system, electroencephalography (EEG), electromyography (EMG), magnetic resonance imaging (MRI), and magnetic resonance angiography (MRA). Patients with other connective tissue disease knowingly responsible for nervous system involvement were excluded from the analyses.

RESULTS

A total of 182 case reports/studies addressing SSc and 50 referring to LS were identified. SSc patients totalized 9506, while data on 224 LS patients were available. In LS, seizures (41.58%) and headache (18.81%) predominated. Nonetheless, descriptions of varied cranial nerve involvement and hemiparesis were made. Central nervous system involvement in SSc was characterized by headache (23.73%), seizures (13.56%) and cognitive impairment (8.47%). Depression and anxiety were frequently observed (73.15% and 23.95%, respectively). Myopathy (51.8%), trigeminal neuropathy (16.52%), peripheral sensorimotor polyneuropathy (14.25%), and carpal tunnel syndrome (6.56%) were the most frequent peripheral nervous system involvement in SSc. Autonomic neuropathy involving cardiovascular and gastrointestinal systems was regularly described. Treatment of nervous system involvement, on the other hand, varied in a case-to-case basis. However, corticosteroids and cyclophosphamide were usually prescribed in severe cases.

CONCLUSIONS

Previously considered a rare event, nervous system involvement in scleroderma has been increasingly recognized. Seizures and headache are the most reported features in LS en coup de sabre, while peripheral and autonomic nervous systems involvement predominate in SSc. Moreover, recently, reports have frequently documented white matter lesions in asymptomatic SSc patients, suggesting smaller branches and perforating arteries involvement.

Gastrointestinal symptoms and motility disorders in patients with systemic scleroderma

BACKGROUND

Studies on gastrointestinal symptoms, dysfunctions, and neurological disorders in systemic scleroderma are lacking so far.

METHODS

Thirty-eight scleroderma patients (34 limited, 4 diffuse), 60 healthy controls and 68 dyspeptic controls were scored for upper and lower gastrointestinal symptoms (dyspepsia, bowel habits), gastric and gallbladder emptying to liquid meal (functional ultrasonography) and small bowel transit (H2-breath test). Autonomic nerve function was assessed by cardiovascular tests.

RESULTS

The score for dyspepsia (mainly gastric fullness) was greater in scleroderma patients than healthy controls, but lower than dyspeptic controls who had multiple symptoms, instead. Scleroderma patients with dyspepsia had a longer disease duration. Fasting antral area and postprandial antral dilatation were smaller in scleroderma patients than dyspeptic and healthy controls. Gastric emptying was delayed in both scleroderma patients (particularly in those with abnormal dyspeptic score) and dyspeptic controls, who also showed a larger residual area. Despite gallbladder fasting and postprandial volumes were comparable across the three groups, gallbladder refilling appeared delayed in dyspeptic controls and mainly dependent on delayed gastric emptying in scleroderma. Small intestinal transit was also delayed in 74% of scleroderma and 66% of dyspeptic controls. Bowel habits were similar among the three groups. Autonomic neuropathy was not associated with dyspepsia, gastric and gallbladder motility and small intestinal transit.

CONCLUSION

In scleroderma patients dyspepsia (mainly gastric fullness), restricted distension of the gastric antrum and diffuse gastrointestinal dysmotility are frequent features. These defects are independent from the occurrence of autonomic neuropathy.

Variations of neuronal nitric oxide synthase in systemic sclerosis skin

OBJECTIVE

In systemic sclerosis (SSc), derangement of the peripheral nervous system is linked to vascular tone dysfunction. Nitric oxide (NO) produced by neuronal nitric oxide synthase (nNOS, NOS-I) might play a dynamic role in the control of vascular tone. This study was performed to verify, by immunohistochemical and biochemical analyses, the presence and expression of nNOS and protein gene product 9.5 (PGP 9.5) in SSc skin, in different subsets and various phases of the disease.

METHODS

Biopsy samples of clinically involved skin from 32 SSc patients (12 with limited cutaneous SSc [lcSSc] and 20 with the diffuse form [dcSSc]) and skin samples from 6 healthy controls were either immunostained with anti-PGP 9.5 and anti-nNOS antibodies or analyzed by semiquantitative reverse transcription-polymerase chain reaction and Western blotting.

RESULTS

Immunohistochemical and biochemical data showed a decrease in PGP 9.5 and nNOS innervation and in their messenger RNA (mRNA) levels in lcSSc and dcSSc skin. In the edematous phase of SSc, a light alteration in cutaneous innervation was initiated and slowly progressed into the sclerotic phase, becoming most evident in the atrophic phase. Levels of nNOS mRNA were significantly lower between the edematous phase and the sclerotic phase in both dcSSc and lcSSc skin, which was attributable to the earlier occurrence of more severe pathologic alterations.

CONCLUSION

Total cutaneous innervation and nNOS innervation slowly disappear in the skin of SSc patients. Expression of nNOS depends on the severity of tissue damage in SSc, and increased synthesis of NO also contributes to this process. It remains to be determined whether the changes in cutaneous innervation are due to the disease itself or whether these changes contribute to the pathogenesis and evolution of SSc.

Damage of cutaneous peripheral nervous system evolves differently according to the disease phase and subset of systemic sclerosis

OBJECTIVE

Evidence shows that peripheral nervous system (PNS) is involved in systemic sclerosis (SSc), but few morphological studies have assessed the ultrastructural pathological modifications. The aim was to study ultrastructural modifications of skin PNS fibres in SSc according to subsets [limited SSc (lSSc) and diffuse SSc (dSSc)] and phases (early and advanced) of the disease.

METHODS

Skin biopsies were taken from the forearms of 23 SSc patients (11 lSSc and 12 dSSc) and 10 controls. Each biopsy was processed for transmission electron microscopy (TEM).

RESULTS

At TEM, observation in skin from early lSSc, signs of inflammation were evident, while PNS fibres were not damaged. The microvascular wall showed hypertrophic endothelial cells bulging into the lumen. In advanced lSSc, fibrosis prevailed on inflammation and slight ultrastructural alterations of PNS fibres were evident in the papillary derma. In early dSSc, ultrastructural alterations of PNS fibres, similar to those observed in the advanced phase of lSSc, were found together with signs of inflammation and fibrosis. In advanced dSSc, in the papillary and reticular dermis PNS fibres were reduced and showed relevant ultrastructural alterations.

CONCLUSIONS

In SSc, PNS ultrastructure damage is linked to the progression and severity of skin involvement. The alterations evolve from the early to the advanced phase mainly in the diffuse subset. In particular, the severe PNS lesions found in advanced lSSc are already present and widely diffuse in early dSSc and the microvascular involvement in early lSSc seems to precede the modification of the PNS in the skin. Thus, an early therapeutic approach can be useful to reduce the progression of PNS and skin damage in SSc patients.

Blink reflex discloses CNS dysfunction in neurologically asymptomatic patients with systemic sclerosis

OBJECTIVE

To investigate trigeminal-nerve, brain-stem, and brain function, in order to disclose a possible nervous system involvement in neurologically asymptomatic systemic sclerosis (SSc) patients.

METHODS

Using a standard electromyographic (EMG) technique, we recorded the early (R1) and late (R2) components of the blink reflex in 35 SSc patients with no history or signs of cranial-nerve impairment and 20 control subjects. SSc patients were classified as limited or diffuse SSc and also evaluated for disease duration, autoantibody pattern (ANA, ACA, Scl70) and skin score (by Rodnan modified method).

RESULTS

Whereas no SSc patients had an abnormal R1, six (18%) had delayed R2 responses. We found no correlation between R2 latency and clinical or laboratory data.

CONCLUSIONS

Whereas previous studies reported both R1 and R2 abnormalities (reasonably due to trigeminal neuropathy) in symptomatic SSc patients, we found selective abnormalities of the R2 components in asymptomatic patients. The selective R2 abnormality is secondary to a central dysfunction, either because of a direct impairment of the polysynaptic circuits in the medulla, or because of a decreased cortico-reticular drive on these circuits. The lack of overt trigeminal symptoms in our patients favours a suprasegmental dysfunction, possibly due to microvascular lesions disseminated in the subcortical white matter.

The use of pupillometry in joint and connective tissue diseases

The central and peripheral nervous systems are variably affected in the rheumatic diseases. Automated standardized infrared pupillometry allows the safe, noninvasive assessment of the pupillary innervation. Pupillometry has already been used in studying the autonomic nervous system (ANS) in various rheumatic diseases. In systemic lupus erythematosus, the irideal parasympathetic branch of ANS was more affected then the sympathetic branch. In Sjögren's syndrome, signs of pupillary parasympathetic denervation have been reported. In rheumatoid arthritis, pupil parasympathetic dysfunction has been shown to correlate with ocular dryness. In systemic sclerosis (SSc), both sympathetic and parasympathetic irideal impairment have been demonstrated. Beside providing autonomic innervation, sensory nerves fibers are able to control iris diameter. Exogenous ocular instillation of substance P (SP), a sensory neuropeptide, can determine an omathropine-resistant, non-cholinergic myosis, acting on specific receptors present on the iris sphincter muscle. We first studied pupillary SP-ergic responsiveness in SSc, evaluating substance P (SP)-stimulated pupillary diameters by pupillometry. A higher basal and SP-stimulated myosis was found in lSSc versus both dSSc and controls, whereas no differences existed between dSSc and controls. From the literature, the pupillary parasympathetic nervous system seems to be more affected than the sympathetic branch of ANS in the rheumatic diseases characterized by an inflammatory status. However, we found in SSc both sympathetic and parasympathetic pupil control to be equally impaired. From our experience, we conclude that pupillary nervous control is differently affected in the two subsets of SSc, and that the SP-ergic system seems to be impaired only in lSSc.

[The carpal tunnel syndrome in the oil toxic syndrome]

BACKGROUND

The toxic oil syndrome (TOS) is an autoimmune disease caused by the ingestion of aniline-denatured rapeseed oil. The carpal tunnel syndrome (CTS) is an entrapment neuropathy due to the median nerve entrapment, which is associated with both occupational activities and autoimmune diseases. The objective of this work was to know the frequency and characteristics of CTS in TOS patients.

PATIENTS AND METHODS

Between December 1977 and July 2000, 744 TOS patients were evaluated. The inclusion criteria were: the clinical records for patients diagnosed between May 1981 and November 1997; and for patients diagnosed between December 1997 and July 2000, symptoms with the classical or likely pattern according to the Katz's hand diagram and one of the following findings: a) abnormal electromyogram, and b) hypalgesia in the median nerve territory and positive Tinel and/or Phalen signs.

RESULTS

A total of 70 patients (63 women, 90%) were diagnosed; 48 of them had been diagnosed before 1997 and 22 subsequently. The mean age of patients was 47.6 (20-78) years. In 36 patients (51.4%), a bilateral CTS was present. Fifty-six patients (81.4%) had a diagnostic EMG, and 31 (44.2%) were obese, 13 (18.6%) diabetic, and 4 (6%) had hypothyroidism. Most of these cases (48; 68.6%) were housewives.

CONCLUSIONS

TOS patients have a high frequency of CTS; therefore, this condition must be suspected in patients with associated obesity and diabetes mellitus.

Nerve growth factor and neuropeptides circulating levels in systemic sclerosis (scleroderma)

OBJECTIVE

To determine the circulating levels of nerve growth factor (NGF), neuropeptide Y (NPY), and vasoactive intestinal peptide (VIP) in systemic sclerosis (SSc), and to correlate these levels with clinical and laboratory features.

METHODS

Forty four patients with SSc were evaluated for circulating NGF (immunoenzymatic assay), NPY and VIP (radioimmunoassay), anticentromere and antitopoisomerase I autoantibodies, lung disease (pulmonary function tests with carbon monoxide transfer factor (TLCO), ventilation scintiscan with 99mTc DTPA radioaerosol, high resolution computed tomography (HRCT), pulmonary pressure (echo colour Doppler)), heart disease (standard and 24 ECG, echocardiography), cutaneous involvement (skin score), joint involvement (evidence of tender or swollen joints, or both), peripheral nervous system (PNS) involvement (electromyography), rheumatoid factor, angiotensin converting enzyme (fluorimetric method), von Willebrand factor (ELISA), and erythrocyte sedimentation rate (ESR) (Westergren).

RESULTS

Circulating NGF levels in SSc were significantly increased compared with controls (p<0.00001) and significantly higher in the diffuse than in the limited subset of patients (p<0.01). Patients with articular disease had significantly higher levels of NGF. A significant indirect correlation between NGF levels and TLCO was detected (p<0.01), but no correlation was found between NGF and HRCT, DTPA, skin score, PNS involvement and angiotensin converting enzyme and von Willebrand factor levels, antitopoisomerase or anticentromere antibodies, and ESR. NGF levels increased progressively as the disease worsened. Similarly, VIP circulating levels were significantly increased in patients with SSc (p<0.001), whereas the increase of NPY levels did not reach statistical significance. However, both neuropeptides, following the same trend as NGF, increased as the disease worsened (skin score and lung disease).

CONCLUSIONS

The increase of NGF and VIP in patients with SSc, the former in the diffuse subset of the disease, and in patients with prominent articular disease, may suggest a link between neurotransmitters and the disease pathogenesis. Neuropeptide circulating levels seem to increase only in patients with the most severe disease.

Intracerebral calcification in systemic sclerosis

BACKGROUND AND PURPOSE

Advanced cerebrovascular wall calcification was recently observed at autopsy in 2 patients with systemic sclerosis. To further investigate this issue, we conducted a prospective CT study of scleroderma patients to detect intracerebral calcification.

METHODS

Thirty-seven consecutive patients with systemic sclerosis underwent unenhanced brain CT. Images were blindly interpreted, together with those of 2 age-matched (+/-1 year) and sex-matched control subjects per patient.

RESULTS

Intracerebral calcification was found in 12 patients (32.4%) and 7 controls (9.5%) (P=0.006). Among the patients, intracerebral calcification was associated with the duration of Raynaud's phenomenon (P=0.005) and not with age (P=0.086).

CONCLUSIONS

Intracerebral calcification is closely associated with scleroderma, which suggests that scleroderma causes primary cerebrovascular changes.

Myenteric neuronal antibodies in scleroderma: passive transfer evokes alterations in intestinal myoelectric activity in a rat model

Although the mechanism for neuropathic gastrointestinal motility disturbances in scleroderma is unknown, we have previously described anti-myenteric antibodies in some patients with scleroderma. The aim of this study was to screen patients with scleroderma who had gastrointestinal symptoms for the presence of anti-myenteric neuronal antibodies and then purify the immunoglobulin G (IgG) fraction from serum samples for passive immunization into a rat model and observe for intestinal motility effects. Patients with scleroderma were screened, a serum sample from a patient with high titer anti-myenteric neuronal antibodies was obtained, and IgG was purified. Using a rat model with chronic indwelling intestinal electrodes to measure intestinal myoelectric activity, we passively transferred the IgG from either control subjects or this patient with scleroderma. We immunosuppressed the rats and intraperitoneally injected IgG from control subjects and this patient with scleroderma daily for 7 days. Recordings of myoelectric activity in control injected rats revealed no difference from baseline, but a prolongation in the activity front duration and interval and a disruption were seen after scleroderma IgG injections. IgG from a patient with scleroderma with antimyenteric neuronal antibodies, when passively immunized into a rat model, evokes intestinal myoelectric activity alterations. We hypothesize that these antibodies could account for the gastrointestinal neuropathic motility disturbances seen in scleroderma.

Raynaud’s Phenomenon and Vascular Disease in Systemic Sclerosis

Raynaud's phenomenon (RP) is very often the first manifestation of SSc preceding the onset of all the other signs and symptoms of the disease. Two structures are involved in the pathogenesis of RP: the endothelium and the peripheral nervous system (PNS). The hypothesis is that SSc modifies consistently the activity of both these systems leading eventually to RP. The disease, through the injury to the endothelium, jeopardizes the basilar endothelial-dependent vascular tone control. An increase of endothelin, a potent endothelial-derived vasoconstrictor, and the reduction of nitric oxide, one of the main endothelial vasodilators, are two key events involved in the genesis of RP. The PNS is also targeted by the disease as demonstrated by the high incidence of neuropathy in SSc patients. A marked reduction of sensory fibres has been detected in SSc skin. Thus, the involvement of nerve terminals reduces the vasodilatory, endothelial dependent or independent, potential of the neuropeptides released by sensory nerve endings. Indeed, an increased sensitivity of alpha 2 adrenoceptors mediated vasoconstriction has been shown in SSc skin. The complex vasodilatory network formed by the interaction between the endothelium and the PNS seems greatly damaged by SSc leading inesorably toward vascular tone dysfunction clinically evident as RP.

Brain involvement in scleroderma: two autopsy cases

BACKGROUND

Neuropathological data are very scarce in systemic sclerosis and fail to demonstrate primary changes in the brains of such patients.

CASE DESCRIPTIONS

A 41-year-old woman with CREST syndrome developed signs of dementia after an episode of severe dehydration and died two months later of septic shock. A 63-year-old woman with CREST syndrome and a history of two unexplained transient ischemic attacks had had balance disorders since age 62. She died of severe pulmonary hypertension. In both cases, the autopsy showed extensive wall calcification of small arteries and arterioles in the brain, primarily in the basal ganglia, and also in the frontal lobes and the cerebellar area in the second case. No known cause of cerebrovascular calcification was found in either patient.

CONCLUSION

The neuropathological findings in these two patients suggest that systemic sclerosis may induce primary vascular changes in the brain, of which calcification may be a marker.