Sclérodermie systémique: épidémiologie et facteurs environnementaux

The role of PET/CT in connective tissue disorders: systemic sclerosis, Sjögren's syndrome and systemic lupus erythematosus

Advanced imaging techniques are needed to help clinicians in the diagnosis, in the choice of the right time for therapeutic interventions or for modifications and monitoring of treatment response in patients with autoimmune connective tissue diseases. Nuclear medicine imaging, especially PET/CT and PET/MRI, may play an important role in detecting disease activity, assessing early treatment response as well as in clarifying the complex mechanisms underlying systemic sclerosis, Sjögren's syndrome or systemic lupus erythematosus. In addition, [¹⁸F]FDG PET/CT may help in excluding or detecting coexisting malignancies. Other more specific radiopharmaceuticals are being developed and investigated, targeting specific cells and molecules involved in connective tissue diseases. Further larger studies with standardized imaging protocol and image interpretation are strongly required before including PET/CT in the diagnostic work-up of subsets of patients with autoimmune connective tissue diseases.

Etiological factors of systemic sclerosis in the southeast region of Romania

Systemic sclerosis (SSc) is a relatively rare autoimmune disease with skin and visceral involvement, having a yet unknown etiopathogenesis. Research has shown that professional exposure to various polluting chemicals such as dyes, aliphatic and aromatic organic solvents, inhalable silica dust or certain heavy metals, can be triggering factors for this disease when they overlap a predisposing genetic profile. Smoking is still a debated factor involved in the etiology of SSc, as authors have divergent opinions on this matter. The present study was designed to analyze the etiological factors identified in the group of 37 patients with diffuse and limited SSc from the southeast region of Romania and the results were compared to the literature data. In the group of patients included in this study, occupational exposure and smoking history were not present in all patients, and a hereditary factor was identified only in an isolated case. The majority of patients suffered from a major negative psychological event or from long-term stressful situations and these factors were associated with smoking history or occupational exposure; this suggests that SSc is initiated in a set of cumulative triggering factors.

Risk factors for the development of systemic sclerosis: a systematic review of the literature

OBJECTIVES

Although numerous studies have investigated the roles of various genetic, epigenetic and environmental factors that may impact its aetiology, SSc is still regarded as an idiopathic disease. Given that there is significant heterogeneity in what has been proposed to influence the development of SSc, this systematic review was conducted to assess the impacts of different factors on the aetiology of scleroderma.

METHODS

The search was performed in the PubMed, CINAHL and SCOPUS databases on 17 May 2017. Any study that made explicit reference to scleroderma or SSc that had information about the risk factors or epidemiology of the disease was included. The extracted outcome variables were prevalence, gender preponderance, geographical distribution, family history and various proposed environmental risk factors.

RESULTS

One thousand five hundred and seventy-four articles were screened for eligibility. Thirty-four articles were eligible for the systematic literature review.

CONCLUSION

Age between 45 and 64 years, female sex, positive family history and exposure to silica were found to be risk factors. There were conflicting findings regarding the impact of exposure to organic solvents and microchimerism. No relationship between infectious agents, alcohol consumption or cigarette smoking and the development of SSc was identified.

[Prevalence of macrovascular arterial involvement of the 4 limbs in systemic sclerosis: About a case series of 14 patients]

INTRODUCTION

Trophic disorders of the extremities are a common complication of systemic sclerosis (SSc), mainly related to microvascular damage. However, SSc seems to be a risk factor for premature athero-thrombotic disease that can affect the peripheral arteries, participate in the occurrence of trophic disorders and promote the occurrence of infectious complications. The objective of this study was to assess the prevalence of arterial disease of the limbs in SSc patients.

METHODS

Consecutive inclusions in the context of a multidisciplinary consultation centered on disability of the hand with collection of clinical data [cardiovascular risk factors (CVRF), history of trophic disorders of ischemic origin, peripheral pulse palpation, Allen maneuver the upper (UL) and lower limbs (LL)], and hemodynamic data (flow recorded by Doppler in radial, ulnar, anterior and posterior tibial arteries, and measurement of systolic indices ankles).

RESULTS

Fourteen patients were included (11 right-handers, 2 left-handers, 1 ambidextrous). The sex-ratio male/female was 0.27 and the average age of 58.1±10.4 years. The main CVRF were age and smoking. In the UL, 42.8% of patients had a history of trophic disorders, Allen maneuver was abnormal for 35.7% of the superficial palmar arch, 42.9% of ulnar pulse were not perceived and there was no recordable flow in 25% of ulnar artery. In the LL, 14.3% of patients had already presented trophic disorders toes, Allen maneuver was abnormal for 15.4% of the posterior tibial artery, 25.6% of posterior tibial pulse were not perceived and flow of 15.4% of posterior tibial arteries was pathological.

CONCLUSION

The distal macrovascular disease preferentially affecting the ulnar and posterior tibial arteries with a high frequency to the UL and two times less at LL. The pathophysiology is unclear but it could be a proper manifestation of SSc. It seems necessary that SSc patients have a strict balance of their CVRF and a screening of macrovascular arterial lesions. There is also the question of the place of an anti-atherosclerotic therapy in these patients.

[Silica-associated systemic sclerosis occurring after an occupational exposure to arc welding]

La sclérodermie systémique liée à l’exposition à la silice cristalline peut apparaître chez les personnes utilisant la soudure à l’arc. Une forme diffuse de sclérodermie a été diagnostiquée chez un plombier-soudeur de 57 ans, qui présentait des polyarthralgies inflammatoires, un phénomène de Raynaud, une sclérodactylie, une sclérose cutanée diffuse, des télangiectasies, une atteinte œsophagienne, une hypertension artérielle pulmonaire et une fibrose pulmonaire associées à la présence d’anticorps anti-nucléosomes. Au cours de son activité professionnelle, le patient était fréquemment exposé à des concentrations atmosphériques élevées de silice cristalline lors de la soudure à l’arc. Le diagnostic d’un syndrome d’Erasmus avec une association d’une sclérodermie systémique à une silicose pulmonaire était retenu. Une déclaration en maladie professionnelle au titre du tableau n°17 en Tunisie a été réalisée.

[Epidemiological, clinical and evolutionary peculiarities of interstitial lung disease in systemic sclerosis]

Pulmonary involvement during systemic sclerosis (SS) is dominated by interstitial lung disease and arterial pulmonary hypertension. It is about a retrospective study analyzing 65 cases of SS over a period of 13 years. We compared cases with and without interstitial lung disease. The diagnosis of SS was retained according to American College of Rheumatology (ACR)/EULAR 2013 criteria. The diagnosis of interstitial lung disease was retained in TDM and EFR. Pulmonary hypertension is defined by a pulmonary arterial pression higher than 25 mmHg. The mean delay of diagnosis of interstitial lung disease and the diagnosis was of 48 months (extremes 0-78 months). The comparison between both groups according to average age of the patients, prevalence of pulmonary hypertension, frequency of Raynaud phenomenon and trophic disorders did not find any significant difference. Lung involvement was associated with an esophageal involvement in 71% of the cases (P=0.059). Antibodies anti-Scl 70 were noted more frequently in patient's with interstitial lung disease (79% of the cases, P=0.001). Patients were treated with colchicine and vitamin E. A corticotherapy had been indicated at a single patient. The evolution of SS was marked by the stabilisation of the restrictive syndrome in 71.8% of the cases and a worsening in 25% of the cases. Early and appropriate diagnosis of SS and screening of lung involvement are essential for a early care.

[Hypertension in scleroderma: A vital emergency]

PURPOSE

In systemic sclerosis, hypertension is feared because it is often heralding severe renal impairment. The objective of our study was to identify the frequency of arterial hypertension and clarify its etiologies in this condition.

PATIENTS/METHODS

Our study was prospective. From January 2008 to May 2012, we have included all patients over the age of 16 years which featured a systemic scleroderma meeting the criteria for classification of Leroy and Medsger modified. Blood pressure was systematic and hypertension was defined as a greater than 140/90 mmHg PAS/PAD.

RESULTS

We have collected 60 patients. It was 50 women and 10 men with an average age of 41.1 ans ± 13.03. Arterial hypertension was noted in sixteen patients (26.7%) with an average age of 48.8 years ± 13.21. It was nine diffuse cutaneous systemic scleroderma of six limited cutaneous scleroderma and one case of scleroderma sine scleroderma. Etiologic research hypertension had concluded to a renal cause in 12 patients. It was five scleroderma renal crisis (SRC), three vascular nephropathies, four chronic kidney failure (CKD) including three terminals and a moderate CKD. An 'essential' so-called HTA was observed in four patients. Hypertension was a major sign that reported five cases of SRC. These patients had received treatment anti hypertensive and renal extra cleansing.

DISCUSSION

Hypertension is common in systemic scleroderma. Our data approximates of literature when its frequency and severity.

CONCLUSION

Hypertension is a major warning sign that under no circumstances should overlook it or novo or secondary aggravation. Its support must be very early under penalty to put at stake the life-threatening in particular during the CRS.

Scleroderma renal crisis

Scleroderma renal crisis (SRC) is characterized by malignant hypertension and oligo-anuric acute renal failure. It occurs in 5% of patients with systemic sclerosis (SSc), particularly in patients with diffuse disease during the first years. SRC is more common in patients receiving corticosteroids, the risk increasing with increasing dose. The disease is sometimes triggered by use of nephrotoxic drugs and/or intravascular volume depletion. Left ventricular insufficiency and hypertensive encephalopathy are typical clinical features. Thrombotic microangiopathy is detected in 43% of cases, and anti-RNA-polymerase III antibodies are present in one-third of patients. Renal biopsy is not necessary if SRC presents classical features. However, biopsy may help to define the prognosis and guide treatment in atypical forms. The prognosis of SRC has greatly improved with the introduction of angiotensin-converting enzyme (ACE) inhibitors. However, the 5-year survival for SSc patients with full SRC remains low (65%). The treatment of SRC relies on aggressive blood pressure control with an ACE inhibitor, combined with other antihypertensive drugs if needed. Dialysis is frequently indicated but can be stopped in about half of patients, mainly those with good blood pressure control. Patients who need dialysis for more than 2 years qualify for renal transplantation.

Scleroderma renal crisis: a rare but severe complication of systemic sclerosis

Scleroderma renal crisis (SRC) is a major complication in patients with systemic sclerosis (SSc). It is characterized by malignant hypertension and oligo/anuric acute renal failure. SRC occurs in 5% of patients with SSc, particularly in the first years of disease evolution and in the diffuse form. The occurrence of SRC is more common in patients treated with glucocorticoids, the risk increasing with increasing dose. Left ventricular insufficiency and hypertensive encephalopathy are typical clinical features. Thrombotic microangiopathy is detected in 43% of the cases. Anti-RNA-polymerase III antibodies are present in one third of patients who develop SRC. Renal biopsy is not necessary if SRC presents with classical features. However, it can help to define prognosis and guide treatment in atypical forms. The prognosis of SRC has dramatically improved with the introduction of angiotensin-converting enzyme inhibitors (ACEi). However, 5 years survival in SSc patients who develop the full picture of SRC remains low (65%). SRC is often triggered by nephrotoxic drugs and/or intravascular volume depletion. The treatment of SRC relies on aggressive control of blood pressure with ACEi, if needed in combination with other types of antihypertensive drugs. Dialysis is frequently indicated, but can be stopped in approximately half of patients, mainly in those for whom a perfect control of blood pressure is obtained. Patients who need dialysis for more than 2 years qualify for renal transplantation.

Therapeutic options for systemic sclerosis related interstitial lung diseases

Interstitial lung disease (ILD) is a common manifestation of systemic sclerosis (SSc) mainly encountered in patients with diffuse disease. Unlike idiopathic interstitial pneumonias (IIP), SSc associated ILD corresponds to non-specific interstitial pneumonia (NSIP) in most cases, whereas usual interstitial pneumonia (UIP) is encountered less frequently. This explains the better prognosis of SSc associated ILD compared to IIP. However, severe restrictive lung disease represents one of the two main causes of disease-related death in SSc patients. The treatment of SSc associated ILD is not very well established. Anti-fibrosing treatments have failed to demonstrate any benefit and cyclophosphamide, which has been used in the treatment of this condition for about 15 years, has recently been evaluated in two prospective randomised studies which showed a significant but modest effect on respiratory function. Since none of the patients included in retrospective or prospective studies were selected on the basis of progression of ILD, and since only a minority of SSc patients develop severe ILD, further studies should focus on the subgroup of SSc patients with worsening ILD. A subgroup of patients with rapidly progressive ILD might benefit from pulsed intravenous cyclophosphamide combined with prednisone 15 mg daily but this remains to be confirmed.

[Diffuse systemic sclerosis after occupational exposure to trichloroethylene and perchloroethylene]

BACKGROUND

Diffuse systemic sclerosis (DSS) is an autoimmune disease that is most often endogenous but which can also be induced by exogenous substances of occupational origin.

PATIENTS AND METHODS

We report a case of DSS involving prolonged intermittent occupational exposure to solvents (trichloroethylene [TCE] and perchloroethylene [PCE]). The disease was rapidly fatal with cardiac arrest secondary to myocardial fibrosis.

DISCUSSION

In the event of exposure to TCE/PCE, we suggest more systematic prevention and diagnosis of DSS.

Systemic sclerosis: a world wide global analysis

The objective of this study was to analyze epidemiological tendencies of systemic sclerosis (SSc) around the world in order to identify possible local variations in the presentation and occurrence of the disease. A systematic review of the literature was performed through electronic databases using the keywords "Systemic Sclerosis" and "Clinical Characteristics." Out of a total of 167 articles, 41 were included in the analysis. Significant differences in the mean age at the time of diagnosis, subsets of SSc, clinical characteristics, and presence of antibodies were found between different regions of the word. Because variations in both additive and nonadditive genetic factors and the environmental variance are specific to the investigated population, ethnicity and geography are important characteristics to be considered in the study of SSc and other autoimmune diseases.

Polyautoimmunity and familial autoimmunity in systemic sclerosis

Characterization of the extent to which particular combinations of autoimmune diseases occur in excess of that expected by chance may offer new insights into possible common pathophysiological mechanisms. The goal of this study was to investigate the spectrum of polyautoimmunity (i.e. autoimmune diseases co-occurring within patients) and familial autoimmunity (i.e. diverse autoimmune diseases co-occurring within families) in patients with systemic sclerosis (SSc). A cross-sectional study of two convenience samples of patients with SSc, one in Canada and the other in Colombia, was performed. History of other autoimmune diseases in the SSc patients as well as a family history of autoimmunity was obtained. Of 719 patients, 273 (38%) had at least one other autoimmune disease. A total of 366 autoimmune diseases were reported, of which the most frequent were autoimmune thyroid disease (AITD, 38%), rheumatoid arthritis (RA, 21%), Sjögren's syndrome (18%), and primary biliary cirrhosis (4%). There were 260 (36%) patients with first-degree relatives with at least one autoimmune disease, of which the most frequent were RA (18%) and AITD (9%). Having at least one first-degree relative with autoimmune disease was a significant predictor of polyautoimmunity in SSc patients. No significant differences in polyautoimmunity or familial autoimmunity were noted between diffuse and limited subsets of disease. Our results indicate that polyautoimmunity is frequent in patients with SSc and autoimmune diseases cluster within families of these patients. Clinically different autoimmune phenotypes might share common susceptibility variants, which acting in epistatic pleiotropy may represent risk factors for autoimmunity.

[Systemic sclerosis in men]

PURPOSE

To study the initial clinical features and describe the outcome of systemic sclerosis in a cohort of French men.

METHODS

Patients with systemic sclerosis based on Leroy's criteria were included. In this retrospective study we compared a cohort of men to a cohort of women, diagnosed between 1997 and 2005 in departments of internal medicine and rheumatology.

RESULTS

One hundred and twenty-one patients were included amongst which thirty-six men. The mean follow-up duration was 6.5 years. The time to diagnosis was significantly shorter in men than in women. Diffuse cutaneous systemic sclerosis, cutaneous ulcers and interstitial syndrome on chest radiograph were more frequent at diagnosis in men than in women. An environmental factor (silica) was observed in only nine men. During the follow-up, incidence of restrictive lung disease was significantly higher in men than in women (37% versus 14% p=0.01) with higher rates of oxygen dependency (22% versus 5% p<0.01). Cumulated survival rates in men were 92% at 5 years, 72% at ten years and 43% at 15 years, respectively. The mean survival was 13 years in men (IC 95%: 10-16) versus 23 years in women (IC 95%: 10-36) with no statistical difference (p=0.27).

CONCLUSION

If interstitial and restrictive lung disease, oxygen dependency and diffuse systemic sclerosis were more frequent in men than in women, this data did not provide any evidence of survival difference between men and women with systemic sclerosis.