M.F. Heymann

Interleukin 34 expression is associated with synovitis severity in rheumatoid arthritis patients

Objectives Interleukin (IL) 34 is a new cytokine implicated in macrophage differentiation and osteoclastogenesis. This study assessed IL-34 expression in the tissue of patients with rheumatoid arthritis (RA). Methods Immunohistochemistry was performed in synovial biopsies from patients with RA (n=20), osteoarthritis (n=3) or other inflammatory arthritis (n=4). IL-34 was detected in the synovial fluid by ELISA and its messenger RNA expression was studied by quantitative PCR in rheumatoid synovial fibroblasts after stimulation by tumour necrosis factor α (TNFα) and IL-1β. Wild-type, jnk1−/−–jnk2−/− and nemo−/− murine fibroblasts and pharmacological inhibition were used to determine the involvement of nuclear factor kappa B (NF-κB) and JNK in that effect. Results IL-34 was expressed in 24/27 biopsies, with three samples from RA patients being negative. A significant association was found between IL-34 expression and synovitis severity. Levels of IL-34 and the total leucocyte count in synovial fluid were correlated. TNFα and IL-1β stimulated IL-34 expression by synovial fibroblasts in a dose/time-dependent manner through the NF-κB and JNK pathway. Conclusion This work for the first time identifies IL-34 expression in the synovial tissue of patients with arthritis. This cytokine, as a downstream effector of TNFα and IL-1β, may contribute to inflammation and bone erosions in RA.

Outcome of Heart Transplants 15 to 20 Years Ago : Graft Survival, Post-transplant Morbidity, and Risk Factors for Mortality

OBJECTIVES The study was conducted to determine the long-term outcome of patients who underwent heart transplantation 15 to 20 years ago, in the cyclosporine era, and identify risk factors for death. METHODS A retrospective analysis was done of 148 patients who had undergone heart transplantation between 1985 and 1991 at a single center. Operative technique and immunosuppressive treatment were comparable in all patients. RESULTS Actuarial survival rates were 75% (n = 111), 58% (n = 86), and 42% (n = 62) at 5, 10, and 15 years, respectively. The mean follow-up period was 12.1 +/- 5.6 years for patients who survived more than 3 months after transplantation (n = 131). The major causes of death were malignancy (35.8%) and cardiac allograft vasculopathy (24.7%). No death related to acute rejection was reported after the first month of transplantation. Graft coronary artery disease was detected on angiography in 66 (50.3%), and 7 (5.3%) had retransplantation. Malignancies developed in 131 patients (48.1%), including skin cancers in 31 (23.6%), solid tumors in 26 (19.8%), and hematologic malignancies in 14 (10.6%). Severe renal function requiring dialysis or renal transplantation developed in 27 patients (20.6%). By multivariable analysis, the only pre-transplant risk factor found to affect long-term survival was a history of cigarette use (p < 0.0004). CONCLUSIONS Long-term survival at 15 years after cardiac transplantation remains excellent in the cyclosporine era. Controlling acute allograft rejection can be achieved but seems to carry a high rate of cancers and renal dysfunction. History of cigarette use affects significantly long-term survival in our study.

Neointimal Hyperplasia after Stenting in a Human Mammary Artery Organ Culture

Although the use of stents has limited the incidence of restenosis, in-stent restenosis remains an important problem. In-stent restenosis is the result of a healing process that induced neointimal hyperplasia through mechanisms that are still not understood. The aim of this study was to analyze the histological consequences of the healing process following stent implantation. Internal mammary arteries from atheroslerotic patients undergoing coronary artery bypass surgery were stented and maintained in culture for 0–28 days. Stent implantation after predilatation induced an extensive loss of endothelial cells whereas direct stenting preserved endothelium between the struts. Morphometric analysis shows that stent placement induced neointimal thickening. Smooth muscle α-actin labeling indicates that neo-intimal formation was mainly due to proliferation and migration of smooth muscle cells. Smooth muscle cell proliferation, assessed by MIB-1 staining, was maximal at day 14 after stent insertion. Human mammary artery organ culture thus provides valuable information on histological consequences of stent implantation with or without predilatation regarding endothelial cell disappearance and neointimal hyperplasia. These data also demonstrate that neointimal thickening induced by stent implantation comprises an intrinsic component resulting from the vessel wall response to stent insertion and suggest that blood factors could play an amplifying but not necessary role.

A New Experimental Rat Model of Osteosarcoma Established by Intrafemoral Tumor Cell Inoculation, Useful for Biology and Therapy Investigations

Satisfactory experimental models for preclinical cancer studies must follow several criteria: (1) reproducibility of the method used to induce the tumor and (2) clinical, pathological and kinetic similarity with the corresponding human tumors. We developed a model of osteosarcoma locally induced by the intrafemoral injection of osteosarcoma (OSR) cells in Sprague-Dawley rats. This method yields nearly 80% of bone tumors at the injection site. These tumors double their volume fairly slowly (in approximately 20 days) and lung metastases occur in 96% of the animals. The OSR cell-induced tumor is characterized by a direct production of mineralized matrix by the tumor cells themselves, as revealed by histochemical analysis. The microarchitectural parameters which were quantified by a microscanner show an increased trabecular bone volume (+238%) when OSR cells were injected in the femur, as compared to controls injected with vehicle. Osteoblastic markers such as alkaline phosphatase, osteopontin, osteocalcin and bone sialoprotein were expressed by the tumor in vivo, whereas the initially injected OSR cells did not express some of these markers, suggesting that OSR cells reacquired an osteoblastic phenotype in a favorable environment. The clinical, radiological and histological data show that this model shares high similarities with the osteocondensing forms of osteosarcoma in humans.

FRI0526 Quality of Ultrasound-Guided Synovial Biopsies Performed in Clinical Practice

Background Synovial tissue is the principal target and end organ involved in the pathogenesis of multiple articular disease processes. Histological and bacteriological analyses of synovial tissue (ST) are useful in clinical practice for the diagnosis of undifferentiated arthritis. Ultrasound (US) allows an evaluation of the synovial thickness and inflammation. It also helps to perform real-time synovial biopsy and detect nearby structures such as tendons, nerves and vessels. Objectives The aim of this study was to assess quantity and quality of synovial tissue obtained by ultrasound guided synovial biopsies, in clinical practice. Methods We retrospectively analysed all synovial biopsies performed between January 2007 and December 2014 in the Rheumatology Department of Nantes University Hospital. Synovial biopsies were performed under real-time US guidance (Philips HD11 XE) using a core biopsy needle with a 14 or 16G calibre semi-automatic Tru-cut needle. This technique allows to collect multiple synovial samples during a single procedure. Hematoxylin and eosin stained slides were analysed by one operator (AN), blindly from clinical data. Size, area, presence/absence of synovial tissue, presence/absence of lining layer, other types of tissues were assessed and compared to pathologists analysis (gold standard). Results 75 biopsy procedures were analysed (73 patients). 125 samples were available for analysis corresponding to a median number of samples taken per patient of 1 (IQR 1–3). Mean length and width of the biopsy samples were 6.34 millimetres (mm) (±3.60) and 1.70 mm (±0.77) respectively. The mean total area of the samples was 8.77 mm2. Biopsies showed synovial tissue at the histological examination in 102 samples (80.1%). The average area of synovial tissue in these samples was 6.36 mm2 corresponding to 72.5% of the total area of biopsied tissue. The other types of tissue present on these biopsies were connective tissue in 101 cases (80.8%), adipose tissue in 42 cases (33.6%), tendon in 14 cases (11.2%) and fibrin in 24 cases (19.2%). The 23 sample retrieving no synovial tissue were composed of fibrin in 15 cases (12%), conjunctive and adipose tissue in 17 cases (13.6%), tendon in 3 cases (3.15%), cartilage in 3 cases (3.15%) and muscle in one case (0.8%). Synovial lining layer was found in 92.6% of the successful biopsies. Interobserver reliability for presence/absence of synovial tissue between AN and the pathologist was high with a kappa coefficient of 0.90 (95%CI =0.763 to 1). Conclusions Our study is the first to assess quality and quantity of synovial tissue obtained by ultrasound guided biopsy, in the clinical setting. In 80% of the biopsy procedures, quantity and quality of the synovial tissue were high enough to allow a proper histological examination. Given the fact that conjunctive and adipose tissues as well as fibrin were frequently seen on histological examination, retrieving a minimal number of 2 samples per patient appears to be required for appropriate pathology assessment in the clinical setting. Disclosure of Interest None declared

SAT0599 Results and Indications of Ultrasound Guided Synovial Biopsies in “Real Life”: Retrospective Analysis of 75 Synovial Biopsies

Background Histological and bacteriological analysis of synovial tissue (ST) is useful for the diagnosis of undetermined monoarthritis or polyarthritis, especially if a septic arthritis or a villonodular synovitis is suspected. Ultrasound (US) allows an evaluation of the synovial tissue thickness and inflammation. It also helps to perform real-time synovial biopsy. The goal of this study was to describe the “real life” indications and results of US guided synovial biopsies. Methods We retrospectively analyzed all synovial biopsies performed between January 2007 and December 2014 in the Rheumatology Department of Nantes University Hospital. Synovial biopsies were performed under real-time US guidance (Philips HD11 XE) using a semi-automatic core biopsy, with a 14 or 16G caliber Tru-cut needle. We collected all data with a standardized form including clinical data (indication, type of joint, side effects, final diagnosis); histological results (presence of synovial tissue, type of cell infiltrate) and microbiological results (PCR, bacteriological, fungal and mycobacterium cultures). We considered the procedure as successful if synovial tissue was found at the histological examination. Results Seventy-four patients underwent 75 synovial biopsies. 46% were women and average age was 58,8 years. Biopsies were performed in the following joints: knee (n=42; 56%), ankle (n=7; 10%), wrist (n=7; 10%), shoulder (n=6; 8%), hip (n=4), sterno-clavicular joint (n=3), elbow (n=3), pubic symphysis (n=1), acromio-clavicular joint (n=1), first metatarsophalangeal joint (n=1). Patients presented a chronic monoarthritis in 43 cases (57%), an acute monoarthritis in 16 cases (21%), a chronic polyarthritis in 13 cases (17%), an acute polyarthritis, a chronic tenosynovitis and a chronic bursitis in 1 case respectively. Indications for the biopsies were a suspicion of septic arthritis in 64 cases (85%) or villo nodular synovitis in 11 cases (15%). Biopsy succeeded in 85% of cases (64 on 75 biopsies performed). When analyzing failed biopsies, we found either fibrin deposition (corresponding with thick synovial tissue visualized with US) or adipose tissue (corresponding with thin synovial tissue visualized with US or small joints). Ten biopsies on 64 resulted in definitive diagnosis: 1 case of amyloid arthritis on a patient having no known myeloma, 1 joint localization of a mantle cell lymphoma, 2 villonodular synovitis, 1 gouty arthritis, 1 osteochondromatosis, 2 septic arthritis (no bacteria found on cultures, but a typical histological aspect), 1 Whipple disease (positive PCR on synovial tissue) and 1 Lyme arthritis (positive PCR on synovial tissue). The histological analysis of the 54 other biopsies showed a non-specific cell infiltrate with lymphocytes and/or macrophages. One patient presented a knee hemarthrosis 48 hours after the US guided biopsy. Conclusions US guided synovial biopsies success in 85% of cases. This technique allows to biopsy all joints, especially small joints as sterno-clavicular joint or pubic symphysis. Side effects are rare. Synovial biopsy allowed in one over eight cases to obtain a definitive diagnosis. In the 54 other cases, synovial biopsy excludes septic or tumoral synovitis, allowing intra articular injections of glucocorticoids or other immunosuppressive treatments. Disclosure of Interest None declared

Endocardite infectieuse à hémocultures négatives

Resume Les endocardites a hemocultures negatives posent un probleme diagnostique, therapeutique et pronostique. Nous rapportons le cas d’un homme de 57 ans avec pour seul antecedent un rhumatisme articulaire aigu. En aout 2000, decouverte d’une thrombose veineuse surale du membre inferieur droit sans facteur favorisant retrouve. Mise en route d’un traitement par AVK. En octobre 2000, mise en evidence d’une occlusion du tronc tibio-peronier droit et d’une thrombose suspendue de l’artere poplite gauche dans un contexte de claudication du membre inferieur droit. Une EI est suspectee apres 2 autres episodes emboliques et sur l’antecedent rhumatismal. Ce diagnostic est confirmee par ETO : fuite aortique associee a des vegetations de 8 mm. Les hemocultures sont negatives. Un interrogatoire policier a la recherche d’une porte d’entree fait suspecter une maladie de Whipple devant la notion d’arthralgies associees a une diarrhee intermittente avec perte de poids et ceci malgre des biopsies jejunales negatives. Le diagnostic sera pose sur la valvule aortique resequee pour remplacement par homogreffe et sur la relecture des thrombi reseques anterieurement. Examen anatomopathologique : reaction inflammatoire a predominance macrophagique avec inclusions PAS positives cytoplasmiques. Confirmation par immunohistochimie avec Ac anti-tropheryma whipplei et par PCR. Conclusion La maladie de Whipple doit etre evoquee devant toute EIHN avec contexte evocateur (diarrhee, perte de poids, arthralgies). L’examen anatomopathologique reste primordial et peut etre complete par biologie moleculaire. L’atteinte cardiaque au cours du Whipple n’est pas rare. Le pronostic reste sombre si une antibiotherapie adaptee et au long cours n’est pas mise en place rapidement.