Exploring necrotizing autoimmune myopathies with a novel immunoassay for anti-3-hydroxy-3-methyl-glutaryl-CoA reductase autoantibodies

Introduction

Necrotizing autoimmune myopathies (NAM) have recently been defined as a distinct group of severe acquired myopathies, characterized by prominent myofiber necrosis without significant muscle inflammation. Because of the lack of appropriate biomarkers, these diseases have been long misdiagnosed as atypical forms of myositis. NAM may be associated to autoantibodies directed against signal recognition particle (SRP) or 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR). The objective of this work was to quantify anti-HMGCR autoantibodies in patients with suspicion of NAM through the development of a new addressable laser bead immunoassay (ALBIA).

Methods

Recombinant HMGCR C-domain was bound to fluorescent beads. After incubation with serum, autoantibodies were revealed using class- or subclass-specific anti-human immunoglobulin G (IgG) antibodies. Anti-HMGCR levels were assayed in 150 patients with suspicion of NAM, 142 controls with different inflammatory/autoimmune diseases and 100 healthy donors. Inhibition with free recombinant HMGCR and immunoprecipitation experiments confirmed test specificity. Reproducibility and repeatability were determined from sera with various levels of anti-HMGCR autoantibodies. A multiplex assay (ALBIA-NAM) was also developed to permit the simultaneous quantification of anti-HMGCR and anti-signal recognition particle autoantibodies.

Results

No controls scored positive. Of 150 patients with suspicion of NAM, 24% were positive for anti-HMGCR autoantibodies with levels ranging from 24 to 2,656 AU/mL. Anti-HMGCR positivity could be associated to a cytoplasmic pattern in immunofluorescence assay on HEp-2 cells. Anti-HMGCR-positive patients had high creatine kinase (CK) levels (mean 6,630 IU/L) and only 40% of them had been exposed to statins. Multiplex ALBIA-NAM was equally as effective as monoplex anti-HMGCR and anti-SRP ALBIA.

Conclusions

Both monoplex ALBIA-HMGCR and multiplex ALBIA-NAM reliably detect and quantify anti-HMGCR autoantibodies. A positive result allows ascribing patients with a necrotizing myopathy to an autoimmune form. Anti-HMGCR autoantibodies may be found in patients who have not taken statins.

Rituximab for induction and maintenance treatment of ANCA-associated vasculitides: a multicentre retrospective study on 80 patients

OBJECTIVES

Rituximab has been shown to induce remission of ANCA-associated vasculitides (AAVs). Our study was undertaken to describe AAV clinical responses to rituximab used for remission-induction and/or maintenance therapy, assess rituximab's safety profile and evaluate French clinical practices.

METHODS

This retrospective study concerned AAV patients who had received one or more rituximab infusion between 2002 and January 2011 and had follow-up lasting ≥12 months.

RESULTS

Eighty patients were included, most with refractory or relapsing AAV: 70 (88%) with granulomatosis with polyangiitis (GPA), 9 (11%) with microscopic polyangiitis and 1 (1%) with eosinophilic GPA. Rituximab was the first agent used to induce remission in 73 patients. The two most commonly administered regimens were an infusion of 375 mg/m(2)/week for 4 weeks (54 patients) and an infusion of 1 g every 2 weeks for a month (16 patients). Rituximab was first prescribed to maintain remission in seven patients. Respective 1-, 2-, and 3-year relapse-free survival rates after the first infusion were 80% (95% CI 72, 89), 63% (51, 77) and 52% (39, 70). Relapse-free survival was longer for patients receiving rituximab maintenance therapy (P = 0.002). Among 22 (28%) rituximab-treated patients experiencing severe adverse events, 12 (15%) had infectious complications leading to 4 (5%) deaths. Only 15 (19%) patients had received anti-pneumococcal vaccine before rituximab.

CONCLUSION

Rituximab was able to induce AAV remission and seemed to maintain remission better than other agents, but caution is needed concerning its safety, especially regarding bacterial infections, in this population.

Prospective study to evaluate the association between systemic sclerosis and occupational exposure and review of the literature

INTRODUCTION

Systemic sclerosis (SSc) has complex pathogenesis and likely multifactorial causes. Environmental exposures have been suggested to play a role in SSc pathogenesis, including occupational exposure to pollutants and chemicals as well as use of drugs leading to modulation of immune response. Thus, this case-control study aimed to assess: the relationship between SSc and occupational exposure; and the risk of SSc related to occupational exposure in male and female patients.

METHODS

From 2005 to 2008, 100 patients with a definite diagnosis of SSc were included in the study; 3 age, gender, and smoking habits matched controls were selected for each patient. A committee of experts evaluated blindly occupational exposure to crystalline silica, white spirit, organic solvents, ketones, welding fumes, epoxy resins, and pesticides; an occupational exposure score was calculated for all subjects. Our findings were compared with previous data in the literature.

RESULTS

Increased ORs for SSc were found for: crystalline silica (p<0.0001), white spirit (p<0.0001), aromatic solvents (p=0.0002), chlorinated solvents (p=0.014), trichlorethylene (p=0.044), ketones (p=0.002) and welding fumes (p=0.021). Elevated risk associated with high final cumulative score in SSc was observed for: crystalline silica, white spirit, chlorinated solvents, trichlorethylene, aromatic solvents, any type of solvents, ketones and welding fumes. A marked association between SSc and occupational exposure was further found for: 1) crystalline silica, chlorinated solvents, trichloroethylene, white spirit, ketones and welding fumes in male patients; and 2) white spirit, aromatic solvents, any type of solvent and ketones in female patients. Finally, we did not find an association between SSc and: 1) the use of drugs that have been speculated to play a role in SSc onset (anorexigens, pentazocine, bromocriptine, l-tryptophan); 2) implants - that are prosthesis, silicone implants, and contact lenses; and 3) dyeing hair. In the literature, SSc has been associated with occupational exposure to silica and solvents, while the association between SSc and specific organic solvents and welding fumes has been anecdotally reported.

CONCLUSION

The following occupational factors have an impact in the development of SSc: crystalline silica, white spirit, aromatic solvents, chlorinated solvents, trichlorethylene, ketones and welding fumes. The risk of SSc appears to be markedly associated with high cumulative exposure. Finally, the association between SSc and occupational exposure may be variable according to gender.

Functional outcome and prognostic factors in anti-Jo1 patients with antisynthetase syndrome

INTRODUCTION

The aims of this present study were firstly to assess the outcome, including functional course, in anti-Jo1 positive patients with antisynthetase syndrome (ASS), and secondly to determine predictive parameters of poor outcome in these patients.

METHODS

The medical records of 86 consecutive anti-Jo1 patients with ASS were reviewed in 4 academic centers.

RESULTS

13 patients (15.1%) achieved remission of ASS, whereas 55 (63.9%) improved and 18 (20.9%) deteriorated in their clinical status. Both steroid and cytotoxic drugs could be discontinued in only 4.7% of patients. ASS was associated with decreased quality of life at long-term follow-up: only 69.2% of patients considered to be in remission experienced a return to previous normal activities; and 24.7% of other patients with non-remitting ASS still had a marked reduction of activities (as shown by the disability scale of the Health Assessment Questionnaire). Decreased quality of life was further due to calcinosis cutis (8.1%) and adverse effects of steroid therapy (36%). Factors associated with ASS deterioration were older age, pulmonary and esophageal involvement, calcinosis cutis and cancer. Higher anti-Jo1 levels were further associated with disease severity in ASS patients.

CONCLUSIONS

The present study shows high morbidity related to ASS. Furthermore, we suggest that patients with predictive factors of ASS deterioration may require more aggressive therapy. Our findings also suggest that in anti-Jo1 patients with severe esophageal manifestations, combined high dose steroids and intravenous immunoglobulins might be proposed as the first line therapy. Finally, as cancer occurred in 14% of anti-Jo1 patients, our findings underscore that the search for cancer should be performed in these patients.

Clinical manifestations and outcome of anti-PL7 positive patients with antisynthetase syndrome

BACKGROUND

The aims of the present study were to determine both clinical manifestations and outcome of anti-PL7 patients with antisynthetase syndrome (ASS).

METHODS

The medical records of 15 consecutive anti-PL7 patients with biopsy proven ASS were retrospectively analyzed without prior selection.

RESULTS

Anti-PL7 patients exhibited polymyositis (n=14) and dermatomyositis (n=1); extra-pulmonary manifestations of ASS included: Raynaud's phenomenon (40%), mechanic's hands (33.3%), joint impairment (26.7%), pericardial effusion (20%) and esophageal/gastrointestinal involvement (20%). The outcome of myositis was as follows: remission/improvement (91.7%) and deterioration (8.3%). Fourteen patients (93.3%) experienced interstitial lung disease (ILD). ILD preceded ASS diagnosis (n=5), was identified concomitantly with ASS (n=8) and occurred after ASS diagnosis (n=1). Patients could be divided into 3 groups according to their presenting lung manifestations: acute onset of lung disease (n=1), progressive onset of lung signs (n=11) and asymptomatic patients exhibiting abnormalities consistent with ILD on PFT and HRCT-scan (n=2). No patient had resolution of ILD, whereas 64.3% and 35.7% experienced improvement and deterioration of ILD, respectively. ILD resulted in respiratory insufficiency requiring O2 therapy in 14.3% of cases. Two patients died. Predictive parameters of ILD deterioration were: DLCO<45% at ILD diagnosis and HRCT-scan pattern of usual interstitial pneumonia (UIP).

CONCLUSION

Our series mainly underscores that ILD is frequent in anti-PL7 patients, leading to high morbidity. Our study further suggests that patients with predictive factors of ILD deterioration may require more aggressive therapy, especially the group of patients with DLCO<45% at ILD diagnosis and UIP pattern on HRCT-scan.

Interstitial lung disease in anti-Jo-1 patients with antisynthetase syndrome

OBJECTIVE

To assess the outcome of interstitial lung disease (ILD) in anti-Jo-1 patients with antisynthetase syndrome, determine predictive variables of ILD deterioration in these patients, and compare features of anti-Jo-1 patients with and without ILD.

METHODS

Ninety-one anti-Jo-1 patients were identified by medical records search in 4 medical centers. All of these patients had undergone pulmonary function tests (PFTs) and high-resolution computed tomography (HRCT) scans.

RESULTS

Sixty-six patients (72.5%) had ILD. Patients could be divided into 3 groups according to their presenting lung manifestations: acute onset of lung disease (n = 12), progressive onset of lung signs (n = 35), and asymptomatic patients exhibiting abnormalities consistent with ILD on PFTs and HRCT scans (n = 19). Sixteen patients had resolution of ILD; 39 and 11 patients experienced improvement and deterioration of ILD, respectively. ILD led to decreased functional status, since 29.8% of patients exhibited a marked reduction of activities due to ILD and 13.6% had respiratory insufficiency requiring oxygen therapy; 5 of 6 patients died due to ILD complications. Predictive parameters of ILD deterioration were HRCT scan pattern of usual interstitial pneumonia, respiratory muscle involvement, and age ≥55 years. Furthermore, anti-Jo-1 patients with ILD, compared with those without, more frequently exhibited mechanic's hands and lower creatine kinase levels.

CONCLUSION

Our findings confirm that ILD is a frequent complication in anti-Jo-1 patients, resulting in high morbidity. We suggest that patients with predictive factors of ILD deterioration may require more aggressive therapy. Finally, anti-Jo-1 patients with ILD, compared with those without, may exhibit a particular clinical phenotype.

[The work placement for developing skills]

The implementation of the reform of nursing studies is a strategic part of the 2009-2013 care project of Millau General Hospital as it has modified the supervision of students on work placements and the organisation of caregivers. In order to make the ten-week work placements a rich learning experience, the teams of the hospital and nurse training institute have designed work placements and tools to provide the best possible support for the students and help them construct a professional identity.