Yves Maugars

From osteoarthritis treatments to future regenerative therapies for cartilage

Osteoarthritis (OA) is associated with cartilage degeneration and an accompanying inflammatory syndrome of the synovium in addition to alteration of the subchondral bone. The molecular and cellular events involved in OA have only partially been elucidated. This review provides a global view of the physiopathology of OA, as well as non-pharmacological and pharmacological treatments for the disorder. An update on surgical treatments and their indications is given with an orientation towards the management of OA and cartilage repair by cell-based regenerative therapies. These promising biological technologies will, potentially, play a major role in the treatment of cartilage-associated diseases.

The Hawthorne effect: Stronger than the placebo effect?

Joint Bone Spine - In Press.Proof corrected by the author Available online since samedi 9 juillet 2011

Regulatory B cells play a key role in immune system balance

Regulatory B cells (Bregs) may act earlier than regulatory T cells (Tregs) and may play as important a role in autoimmune and allergic diseases. Obstacles to the investigation of Bregs are the same as those encountered for Tregs: the regulatory effects are short-lived in some cases, there is no consistent phenotype (C5 expression is neither indispensable nor sufficient), differences exist across species (e.g., between humans and mice), and there are a number of suppression modalities (IL-10, TGF-beta, expression of proapoptotic membrane molecules) that vary across Breg subtypes. The Breg subtypes may be homologous to the Treg subtypes (Br1 cells expressing IL-10, Br3 cells expressing TGF-beta, and B-Foxp3 cells), although the Br1 subtype seems to predominate. Nevertheless, differences with Treg cells may exist: Breg activation may chiefly involve the toll-like receptors rather than the antigen receptor; and Bregs act earlier, facilitating the recruitment of Tregs then disappearing once the Tregs become operational. Bregs make a major contribution to autoimmune disorders associated with several forms of immune deficiency, as well as to the absence of transplant rejection when there is a strong B cell response. Breg deficiencies have been reported in lupus, and the disappointing effects in this disease of treatments designed to inhibit the B cell response may be related to further Breg impairment. In several animal models, Breg stimulation is effective in correcting a variety of autoimmune disorders, most notably those initiated in the mucous membranes. Research into the interactions between the gut microbiota and Bregs holds considerable promise.

Side effects of corticosteroid injections: what's new?

The risk of sepsis with a hip or knee implant does not seem to be increased by prior joint injections, as long as the injection and surgery are separated by at least two months. Calcifications have been reported after intradiscal injection in the coccygeal region for coccydynia. Complete rest for 24 hours after injection of triamcinolone hexacetonide into the knee had no effect on systemic diffusion of the product. Patients infected by HIV who are treated with ritonavir are at much greater risk for Cushing syndrome after epidural injection. Problems with menstruation after corticosteroid injection seem to be related to a transient decrease in estradiol levels, without alterations in FSH and LH levels. The risk of central serous chorioretinopathy and acute necrosis of the retina after injection is not known, even by ophthalmologists. Transient dysphonia occurs in 12% of patients receiving corticosteroid injections. The impressive Tachons syndrome seems to be the venous counterpart to Nicolaus syndrome for arteries. Injections into C1-C2 should be abandoned because of the neurological risks. Since serious neurological events after foraminal injections could be the result of an overly fast injection into the arterialized radicular veins rather than in the arteries, only slow injections with products having a low risk of embolism or vascular complications should be allowed. Dexamethasone-based preparations seem to contain no particles or crystals, and have not induced any neurological accidents in various animal models, even after direct administration into vertebral or carotid arteries.

Overdiagnosing early spondyloarthritis: What are the risks?

Joint Bone Spine - In Press.Proof corrected by the author Available online since samedi 1 juin 2013

Evidence supporting a role for dormant bacteria in the pathogenesis of spondylarthritis

Spondylarthritis is still viewed as a reaction to infectious agents, as opposed to an infection by persistent bacteria, for several reasons: (a) an infection is considered proven only when the organism can be cultured; (b) no studies have identified dormant bacteria in the tissues targeted by spondylarthritis; (c) the bacterial persistence hypothesis has no therapeutic implications at the time being, since antibiotics are effective neither on dormant bacteria nor on the manifestations of spondylarthritis; and (d) the high prevalence of borderline disorders combining features of spondylarthritis and of psoriatic arthritis, or even rheumatoid arthritis (RA), would indicate a role for dormant bacteria in these last two diseases. However, recent data on dormant bacteria have rekindled interest in the bacterial persistence hypothesis. Dormant bacteria cannot be cultured, because they express only a small group of genes, known as the regulon, which includes genes for transcription factors that block the expression of the usual bacterial genes. Certain forms of cell stress, such as molecule misfolding, promote the entry of bacteria into a state of dormancy, which induces the low-level release by the host cells of cytokines such as TNF. Whether HLA-B27 misfolding facilitates the persistence of dormant bacteria within spondylarthritis tissue targets remains to be determined. If it does, then treatments that reactivate dormant bacteria might make these organisms susceptible to appropriate antibiotics and might therefore serve as useful adjuncts to nonsteroidal anti-inflammatory drugs and TNFα antagonists. TNFα antagonists rarely reactivate dormant bacteria, with the exception of Mycobacterium tuberculosis, which, together with metastatic cells, is the most extensively studied latency model to date.

Rheumatoid arthritis and sexuality: A patient survey in France

BackgroundThe objective of this study was to evaluate the impact of rheumatoid arthritis (RA) on patients’ sexuality and identify disease and other factors such as fatigue that most influence sexual relationships.MethodsA specific pretested questionnaire was sent to all members of a French patient association (ANDAR). Questions related to demographics, disease status, quality of life (utility, EQ-5D), pain, psychological status (mood), fatigue and emotional and sexual relationships. To isolate the impact of RA, an attempt was made to include a matched sample from the general population.ResultsThe analysis included 1271 patients, but only 70 controls agreed to participate and comparisons should therefore be considered with caution. The two groups were similar in terms of age, gender distribution, living conditions and diseases other than RA. However, patients scored worse for global health, mood, fatigue, had a lower utility (0.55 versus 0.65). Controls were more active sexually (69% versus 63%), in particular women (71% versus 60%). Age, gender, living alone, physical function and mood were significant predictors for being sexually active for patients; for controls, age and overall quality of life (utility) were significant predictors.ConclusionsWhile it is known that RA has a negative impact on patients’ sexuality, there have been few attempts to quantify the problem. Our study highlights the negative impact of RA on patients’ sexuality, and triggers the question how to include this aspect into care.

Pathogenesis of hyperostosis: A key role for mesenchymatous cells?

The similarities between diffuse idiopathic skeletal hyperostosis (DISH) and some forms of ankylosing spondylitis suggest shared pathogenic mechanisms. Entheseal ossification progresses at the same rate in the two conditions, and spondyloarthritis was the first diagnosis considered in several families with genetically determined early-onset DISH. However, DISH may be a heterogeneous condition, as the presence of peripheral calcifications in some families suggests pathogenic similarities with several animal models combining entheseal ossification and peripheral calcifications, as well as with X-linked familial hypophosphatemia and dentin-matrix-protein mutations. In the far more common presentation of hyperostosis without calcifications, entheseal ossification may be related to abnormal osteoblastic differentiation of mesenchymatous stem cells normally found around the intervertebral disks, in the vertebral periosteum, and in the anterior and posterior longitudinal ligaments. The many factors suspected of promoting this abnormal differentiation include bone morphogenetic proteins (BMPs), retinoids, and various hormonal factors; in addition, adipokines such as leptin are the focus of growing interest based on the well-documented association between DISH and obesity. Confirmation of the role for mesenchymatous cells in DISH should encourage investigations of mesenchymatous cells as possible pathogenic contributors to the entheseal abnormalities seen in spondyloarthritis. These cells normally exert immunosuppressive effects, which may be subverted in spondyloarthritis, notably by a T-cell population that homes specifically to the entheses.

Ultrasonography of the lumbar spine: Sonoanatomy and practical applications

Ultrasonography of the bones and joints has gained considerable ground in the field of rheumatology over the past decade and is now used in everyday practice both for diagnostic purposes and to guide local injections. However, the use of ultrasonography is virtually confined to the peripheral joints, whereas spinal diseases make a major contribution to rheumatology practice. Studies have established that ultrasonography of the lumbar spine is feasible. Adequate equipment and familiarity with spinal sonoanatomy are required. In this update, we suggest starting with a systematic examination of the lumbar spine to assess the various anatomic structures, from the thoracolumbar fascia superficially to the posterior part of the vertebras at the deepest level. The ligaments, erector spinae muscles, facet joints, and transverse processes can be visualized. Ultrasonography can serve to guide injections into the facet joints, about the nerve roots, and into the iliolumbar ligaments; as well as to identify relevant landmarks before epidural injection. Although diagnostic applications are more limited at present, systematic studies of abnormal ultrasonography findings will allow evaluations of the potential usefulness of ultrasonography for diagnosing spinal disorders. The depth of the spinal structures limits the ability to obtain high-resolution images. However, future technical improvements in ultrasound transducers and machines, together with the growing number of physicians trained in ultrasonography, can be expected to benefit the development of spinal ultrasonography in the near future.

Information on glucocorticoid therapy in the main studies of biological agents.

OBJECTIVE To evaluate reported information on prednisone therapy in the main studies of biological agents used to treat rheumatoid arthritis (RA). METHODS We reviewed 66 publications (including four abstracts), including 11 studies of infliximab, 19 of etanercept, eight of adalimumab, five of golimumab, four of certolizumab, four of rituximab, eight of abatacept, and seven of tocilizumab. RESULTS Whether concomitant prednisone therapy was used, it was specified in only 56 (85%) of the 66 publications. Only 42 (64%) publications indicated that the prednisone dosage remained unchanged throughout the study. The maximum prednisone dosage allowed was specified in only 39 (59%) reports and was lower than 8 mg/day in only four (6%) studies. Data enabling determination of the mean daily prednisone dosage in prednisone-treated patients was available for only eight (12%) studies; the mean dosage ranged from 5.0 to 9 mg/day (mean, 7.1 ± 1.5). The percentage of patients receiving prednisone therapy was reported for only 41 (62%) studies. All the above-mentioned information was available in only two (3%) study reports. The percentage of patients on prednisone therapy ranged from 34% to 93% (mean, 58 ± 13%) overall and varied across biological agents as follows: abatacept, 74.4%; golimumab, 67.9%; infliximab, 60.6%; certolizumab, 57.5%; rituximab, 57.5%; etanercept, 54.4%; tocilizumab, 52.8%; and adalimumab, 50.4%. These percentages did not decline between 1997 and 2010. CONCLUSION Study reports provide inadequate information on prednisone therapy during biological treatment for RA.