A descriptive, cross-sectional study characterizing bone erosions in rheumatoid arthritis and gout by ultrasound

The aim of this study is to characterize bone erosions in metatarsal heads (MTH) in rheumatoid arthritis (RA) and gout by grayscale ultrasound. In a descriptive, cross-sectional study, we evaluated 40 patients with RA and 40 with gout, both diagnosed according to the American College of Rheumatology/European League Against Rheumatism criteria, respectively. All patients had bone erosion demonstrated by ultrasound, which was used, following OMERACT criteria, to describe the shape, size, number, border definition, overhanging margin, topography (intra- or extra-articular), and distribution (over dorsal, medial, lateral, or plantar aspect) of the lesions in the MTH. Descriptive statistics were used and a concordance exercise between two ultrasonographers blinded to the diagnosis was performed. Bone erosions in RA were observed most frequently at the plantar and lateral aspect of the fifth MTH, round in 96 %, small-sized (2.43 ± 0.9 mm), intra-articular (100 %), and single (75 %). Few bone erosions had a well-defined border an overhanging margin while in gout were found most frequently in the medial and dorsal aspect of the first MTH, single in 71 %, intra-articular in 100 %, and of median size (4.0 ± 2.3). For shape, 51 % was round and 49 % was oval. A well-defined border was present in 39 %, and an overhanging margin in 62 %. Inter-rater reliability kappa was excellent (0.81, 95 % CI 0.56-1.00). Some characteristics of bone erosions in RA, including shape, size, ill-defined border, and localization in the fifth MTH could distinguish the lesions from gout. Grayscale US has excellent reliability to describe bone erosions in RA and gout.

Chikungunya in the region of the Americas. A challenge for rheumatologists and health care systems

At the end of 2013, the Pan American Health Organization issued an epidemiological alert due to the detection of the first local cases of Chikungunya in the Americas. By August 2015, autochthonous transmissions were detected in 33 countries and territories of the Americas. Latin America has reported nearly one million cases; only Colombia has issued a report of >200,000 cases during the first 4 months of 2015. In some Latin American and Caribbean countries, Chikungunya becomes a major public health problem. The disease commonly exhibits a self-limited course of arthritis, usually lasting for a few days or that may be prolonged to weeks; however, in 10-60 % of cases, joint pain may become chronic and persist for up to 3-5 years. Human-caused environmental changes, such as climate change, the globalization of international exchange, and disordered urban growth, are some factors that aid in its emergence and dissemination. Outbreaks of Chikungunya comprise a challenge for health care systems and rheumatologists because of the high attack rate on the population and the anticipated development of post-Chikungunya chronic rheumatism. This review emphasizes the rheumatologic clinical manifestations reported in the American continent and highlights the challenges that health care systems face in the absence of an effective vaccine and specific treatment to fight Chikungunya.

Ultrasound in the interstitial pulmonary fibrosis. Can it facilitate a best routine assessment in rheumatic disorders?

Ultrasound (US) is increasing its potential in the assessment of several rheumatic disorders. Recently, different applications of this imaging technique have emerged. Interesting data supporting its utility and validity in the assessment of the lung to detect and quantify interstitial pulmonary fibrosis in rheumatic diseases, even in subclinical phases, have been reported. The main purpose of this review is to provide an overview of the role of US in the assessment of interstitial pulmonary fibrosis in rheumatic disorders and to discuss the current evidence supporting its clinical relevance in daily clinical practice.

Monosodium urate crystals induce oxidative stress in human synoviocytes

Background

Gout is the most common inflammatory arthropathy of metabolic origin and it is characterized by intense inflammation, the underlying mechanisms of which are unknown. The aim of this study was to evaluate the oxidative stress in human fibroblast-like synoviocytes (FLS) exposed to monosodium urate (MSU) crystals, which trigger an inflammatory process.

Methods

Human FLS isolated from synovial tissue explants were stimulated with MSU crystals (75 μg/mL) for 24 h. Cellular viability was evaluated by crystal violet staining, apoptosis was assessed using Annexin V, and the cellular content of reactive oxygen species (ROS) and nitrogen species (RNS) (O₂^-, H₂O₂, NO) was assessed with image-based cytometry and fluorometric methods. In order to determine protein oxidation levels, protein carbonyls were detected through oxyblot analysis, and cell ultrastructural changes were assessed by transmission electron microscopy.

Results

The viability of FLS exposed to MSU crystals decreased by 30 % (P < 0.05), while apoptosis increased by 42 % (P = 0.01). FLS stimulated with MSU crystals exhibited a 2.1-fold increase in H₂O₂ content and a 1.5-fold increase in O₂^- and NO levels. Oxyblots revealed that the spots obtained from FLS protein lysates exposed to MSU crystals exhibited protein carbonyl immunoreactivity, which reflects the presence of oxidatively modified proteins. Concomitantly, MSU crystals triggered the induction of changes in the morphostructure of FLS, such as the thickening and discontinuity of the endoplasmic reticulum, and the formation of vacuoles and misfolded glycoproteins.

Conclusions

Our results prove that MSU crystals induce the release of ROS and RNS in FLS, subsequently oxidizing proteins and altering the cellular oxidative state of the endoplasmic reticulum, which results in FLS apoptosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1012-3) contains supplementary material, which is available to authorized users.

Clinical and regulatory perspectives on biosimilar therapies and intended copies of biologics in rheumatology

Biologics are vital to the management of patients with rheumatic and musculoskeletal diseases such as rheumatoid arthritis and other inflammatory and autoimmune conditions. Nevertheless, access to these highly effective treatments remains an unmet medical need for many people around the world. As patents expire for existing licensed biologic (originator) products, biosimilar products can be approved by regulatory authorities and enter clinical use. Biosimilars are highly similar copies of originator biologics approved through defined and stringent regulatory processes after having undergone rigorous analytical, non-clinical, and clinical evaluations. The introduction of high-quality, safe, and effective biosimilars has the potential to expand access to these important medicines. Biosimilars are proven to be similar to the originator biologic in terms of safety and efficacy and to have no clinically meaningful differences. In contrast, “intended copies” are copies of originator biologics that have not undergone rigorous comparative evaluations according to the World Health Organization recommendations, but are being commercialized in some countries. There is a lack of information about the efficacy and safety of intended copies compared with the originator. Furthermore, they may have clinically significant differences in formulation, dosages, efficacy, or safety. In this review, we explore the differences between biosimilars and intended copies and describe key concepts related to biosimilars. Familiarity with these topics may facilitate decision making about the appropriate use of biosimilars for patients with rheumatic and musculoskeletal diseases.

Short-term efficacy to conventional blind injection versus ultrasound-guided injection of local corticosteroids in tenosynovitis in patients with inflammatory chronic arthritis: A randomized comparative study

OBJECTIVE

To compare the short-term efficacy of conventional blind injection (CBI) versus ultrasound-guided injection (USGI) of corticosteroids (CS) injection in tenosynovitis in patients with chronic arthritis and to investigate if the USGI is a less painful procedure and if there are differences in the changes of US findings during the post injection follow-up.

METHODS

Patients presenting tenosynovitis requiring CS injection were involved. After clinical and US evaluation, patients were randomized to receive CBI or USGI. Efficacy of procedure was assessed by the improvement in both Health Assessment Questionnaire (HAQ) and pain visual analogue scale (VAS), including procedure-VAS global-VAS and local-VAS, after 1 and 4 weeks post-procedure. Power Doppler (PD) and greyscale (GS) US findings were also object of the follow-up. CBI or USGI under an aseptic technique were performed according the local guidelines using 20mg of methylprednisolone acetate.

RESULTS

A total of 114 patients were randomized to receive CBI (54 patients) or USGI (60 patients) procedure. No significant difference was observed in terms of gender, age and pain duration among CBI and USGI groups at baseline. USGI proved to be significantly less painful than CBI (P=0.0001). AUC analysis showed that during the follow up visits, the USGI procedure had significantly better response in HAQ, local-VAS and global-VAS (P=0.0001, P=0.012 and P=0.0001 respectively) compared to CBI. During the follow up period, a significant greater reduction in the PD scores was found in the USGI group compared to the CBI group (P=0.0002), whereas no statistical differences were found in the GS findings between the groups (P=0.5627).

CONCLUSION

Our study demonstrates superiority of USGI over CBI for CS injections in painful tenosynovitis, having better short-term outcomes measured by functional, clinical and US scores. These data support the use of USGI for tenosynovits in typical inpatient and/or outpatient in rheumatological practices.

Assessing Elementary Lesions in Gout by Ultrasound: Results of an OMERACT Patient-based Agreement and Reliability Exercise

OBJECTIVE

To test the reliability of the consensus-based ultrasound (US) definitions of elementary gout lesions in patients.

METHODS

Eight patients with microscopically proven gout were evaluated by 16 sonographers for signs of double contour (DC), aggregates, erosions, and tophi in the first metatarsophalangeal joint and the knee bilaterally. The patients were examined twice using B-mode US to test agreement and inter- and intraobserver reliability of the elementary components.

RESULTS

The prevalence of the lesions were DC 52.8%, tophus 61.1%, aggregates 29.8%, and erosions 32.4%. The intraobserver reliability was good for all lesions except DC, where it was moderate. The best reliability per lesion was seen for tophus (κ 0.73, 95% CI 0.61-0.85) and lowest for DC (κ 0.53, 95% CI 0.38-0.67). The interobserver reliability was good for tophus and erosions, but fair to moderate for aggregates and DC, respectively. The best reliability was seen for erosions (κ 0.74, 95% CI 0.65-0.81) and lowest for aggregates (κ 0.21, 95% CI 0.04-0.37).

CONCLUSION

This is the first step to test consensus-based US definitions on elementary lesions in patients with gout. High intraobserver reliability was found when applying the definition in patients on all elementary lesions while interobserver reliability was moderate to low. Further studies are needed to improve the interobserver reliability, particularly for DC and aggregates.

Ultrasound as an Outcome Measure in Gout. A Validation Process by the OMERACT Ultrasound Working Group

OBJECTIVE

To summarize the work performed by the Outcome Measures in Rheumatology (OMERACT) Ultrasound (US) Working Group on the validation of US as a potential outcome measure in gout.

METHODS

Based on the lack of definitions, highlighted in a recent literature review on US as an outcome tool in gout, a series of iterative exercises were carried out to obtain consensus-based definitions on US elementary components in gout using a Delphi exercise and subsequently testing these definitions in static images and in patients with proven gout. Cohen's κ was used to test agreement, and values of 0-0.20 were considered poor, 0.20-0.40 fair, 0.40-0.60 moderate, 0.60-0.80 good, and 0.80-1 excellent.

RESULTS

With an agreement of > 80%, consensus-based definitions were obtained for the 4 elementary lesions highlighted in the literature review: tophi, aggregates, erosions, and double contour (DC). In static images interobserver reliability ranged from moderate to almost perfect, and similar results were found for the intrareader reliability. In patients the intraobserver agreement was good for all lesions except DC (moderate). The interobserver agreement was poor for aggregates and DC but moderate for the other components.

CONCLUSION

These first steps in evaluating the validity of US as an outcome measure for gout show that the reliability of the definitions ranged from moderate to excellent in static images and somewhat lower in patients, indicating that a standardized scanning technique may be needed, before testing the responsiveness of those definitions in a composite US score.

Polymorphic variation of hypoxia inducible factor-1 A (HIF1A) gene might contribute to the development of knee osteoarthritis: a pilot study

Background

Osteoarthritis (OA) is a multifactorial degenerative condition of the whole joint with a complex pathogenesis whose development and progression is significantly mediated by interactions between the joint cartilage and articular tissues, particularly, proinflammatory mediators and oxidative stress, which results in cartilage deterioration and subchondral bone destruction. HIF-1 alpha regulates oxygen homeostasis in hypoxic tissues such as joint cartilage; efficiency of transcriptional activity of the HIF1A gene is strongly influenced by the presence of polymorphic variants. Given the loss of articular cartilage and with intention to restore damaged tissue, WISP-1 participates in the development of subchondral bone; further, its expression is highly increased in chondrocytes of OA patients. The aim of this study was to evaluate gene frequencies of HIF1A and WISP1 polymorphisms in Mexican patients suffering from knee OA.

Methods

We determined HIF1A rs11549465 (P582S), rs11549467 (A588T), and rs2057482 (C191T), and WISP1 rs2929970 (A2364G) polymorphisms in 70 Mexican patients with knee OA and compare them to those present in 66 ethnically matched healthy controls. Genotyping for these polymorphisms was performed by Real-Time PCR using TaqMan probes.

Results

Gene frequencies exhibited a significant increase of the CC genotype of rs11549465 polymorphism in knee OA patients as compared with those present in controls (P = 0.003 OR = 5.7, 95 % CI = 1.7–21.6); CT genotype and T allele showed decreased frequency in the knee OA group vs. the controls (P = 0.003 OR = 0.2, CI = 0.05–0.6; and P = 0.004 OR = 0.2, CI = 0.05–0.65, respectively). Allele frequencies of the other polymorphic variants were similar in both patients and controls.

Conclusions

These results suggest that the presence of the rs11549465 SNP (HIF1A) plays a role protective in the loss of articular cartilage in our population, and offers the possibility to further study the molecular mechanisms within cartilage and subchondral bone.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0678-z) contains supplementary material, which is available to authorized users.

The use of renal replacement therapy in critically ill pediatric small bowel transplantation candidates and recipients: Experience from one center

Outcomes for pediatric SBT patients requiring perioperative RRT in the PICU remain unknown. The objectives were to document our center's experience with PICU SBT patients receiving perioperative RRT and to identify variables predictive of survival to discharge. A retrospective chart review of patients (ages, 0-18 yr) between January 1, 2000 and December 31, 2011 that received RRT within a SBT perioperative period and were transplanted at our university-affiliated, tertiary care children's hospital was performed. Six SBT patients received perioperative RRT (ages, 5-12 yr). Three patients (50%) survived to hospital discharge. Among survivors, RRT was required for a total of 1-112 days (mean, 49.7 days). All three survivors survived to hospital discharge without renal transplantation and free of RRT. There was a trend toward increased survival among older patients receiving RRT (p = 0.05). Survivors had a higher I-125 GFR prior to PICU admission (p = 0.045). A higher I-125 GFR prior to PICU admission among survivors may support this test's utility during SBT evaluation. In our experience, a high survival rate and freedom from RRT at the time of discharge support RRT use in the SBT population.

Effects of two calculolytic diets on parameters of feline mineral metabolism

OBJECTIVES

To evaluate the influence of two feline calculolytic diets on selected parameters of mineral metabolism.

MATERIALS AND METHODS

Two dry commercial diets designed for struvite urolith dissolution were evaluated in 14 cats. The study was designed as a two-sequence, four-period crossover protocol with a baseline period, two 60-day "run-in" periods in which calculolytic diets (Diet 1 and Diet 2) were fed and one 30-day "wash-out" period. Data are expressed as median (range).

RESULTS

Feeding the calculolytic diets for two months did not alter plasma concentrations of calcium, phosphorus, magnesium and parathyroid hormone. A significant (P < 0.05 in each case) decline in calcitriol was observed after administering both diets from 236.4 (122.4-429.6) to 170.4 (108.0-394.3) pmol/L (Diet 1) and from 278.4 (153.6-492.0) to 177.1 (87.6-392.4) pmol/L (Diet 2). Cats fed Diet 1 showed a significant increase in urine calcium concentration (from 0.3 (0.2-0.5) to 0.4 (0.3-0.7) mmol/L). Magnesium concentration in urine was significantly increased with both diets, from 1.4 (0.1-1.7) to 1.5 (1.3-2.4) mmol/L (Diet 1) and from 1.1 (0.4-1.9) to 2.0 (0.1-3.1) mmol/L (Diet 2).

CLINICAL SIGNIFICANCE

Both diets resulted in an increased urinary concentration of magnesium, through different mechanisms: urine acidification (Diet 1) and increased sodium load (Diet 2).

International Consensus for ultrasound lesions in gout: results of Delphi process and web-reliability exercise

OBJECTIVE

To produce consensus-based definitions of the US elementary lesions in gout and to test their reliability in a web-based exercise.

METHODS

The process consisted of two steps. In the first step a written Delphi questionnaire was developed from a systematic literature review and expert international consensus. This collated information resulted in four statements defining US elementary lesions: double contour (DC), tophus, aggregates and erosion. The Delphi questionnaire was sent to 35 rheumatology experts in US, asking them to rate their level of agreement or disagreement with each statement. The second step tested the reliability by a web-exercise. US images of both normal and gouty elementary lesions were collected by the participants. A facilitator then constructed an electronic database of 110 images. The database was sent to the participants, who evaluated the presence/absence of US elementary lesions. A group of 20 images was displayed twice to evaluate intra-reader reliability.

RESULTS

A total of 32 participants responded to the questionnaires. Good agreement (>80%) was obtained for US definitions on DC, tophus, aggregates and erosion in the Delphi exercise after three rounds. The reliability on images showed inter-reader κ values for DC, tophus, aggregates, erosion findings of 0.98, 0.71, 0.54 and 0.85, respectively. The mean intra-reader κ values were also acceptable: 0.93, 0.78, 0.65 and 0.78, respectively.

CONCLUSION

This, the first consensus-based US definition of elementary lesions in gout, demonstrated good reliability overall. It constitutes an essential step in developing a core outcome measurement that permits a higher degree of homogeneity and comparability between multicentre studies.

Rank diversity of languages: generic behavior in computational linguistics

Statistical studies of languages have focused on the rank-frequency distribution of words. Instead, we introduce here a measure of how word ranks change in time and call this distribution rank diversity. We calculate this diversity for books published in six European languages since 1800, and find that it follows a universal lognormal distribution. Based on the mean and standard deviation associated with the lognormal distribution, we define three different word regimes of languages: "heads" consist of words which almost do not change their rank in time, "bodies" are words of general use, while "tails" are comprised by context-specific words and vary their rank considerably in time. The heads and bodies reflect the size of language cores identified by linguists for basic communication. We propose a Gaussian random walk model which reproduces the rank variation of words in time and thus the diversity. Rank diversity of words can be understood as the result of random variations in rank, where the size of the variation depends on the rank itself. We find that the core size is similar for all languages studied.

The OMERACT Ultrasound Working Group 10 Years On: Update at OMERACT 12

Musculoskeletal ultrasound (US) now thrives as an established imaging modality for the investigation and management of chronic inflammatory arthritis. We summarize here results of the Outcome Measures in Rheumatology (OMERACT) US working group (WG) projects of the last 2 years. These results were reported at the OMERACT 12 meeting at the plenary session and discussed during breakout sessions. Topics included standardization of US use in rheumatic disease over the last decade and its contribution to understanding musculoskeletal diseases. This is the first update report of WG activities in validating US as an outcome measure in musculoskeletal inflammatory and degenerative diseases, including pediatric arthritis, since the OMERACT 11 meeting.

Animal model of acute gout reproduces the inflammatory and ultrasonographic joint changes of human gout

INTRODUCTION

Gout is an inflammatory condition induced by the deposition of monosodium urate (MSU) crystals in the joints and soft tissues that can produce acute or chronic arthritis. Several animal models of crystal-induced inflammation have been proposed that involve direct injection of MSU-crystals into different anatomical structures; however, only a few of these models reflect a true diarthrodial joint microenvironment in which an acute gouty attack takes place. The aim of this study was to assess the inflammatory and structural joint changes in a rabbit model of acute gout attack by ultrasound (US), synovial fluid (SF) and histopathological analyses.

METHODS

Under US guidance, 42 rabbit knees were randomly injected with a suspension of 50 mg/ml of either MSU or allopurinol synthetic crystals. The control group received intra-articular vehicle of phosphate-buffered saline (PBS). US evaluation, SF and histopathological analyses were performed at days 1, 3, and 7.

RESULTS

A total of 21 rabbit knees were assigned to the control group, 12 to the MSU-crystals group, and 9 to the allopurinol crystals group. By US, the MSU crystals group displayed the double contour sign and bright stippled aggregates in 67% and 75% of joints, respectively. Neither control knees nor allopurinol crystals group displayed these US signs. Power Doppler (PD) signal was moderate to intense in the MSU-crystals group and greater than both the allopurinol crystal and control groups at day 1 (P<0.001) and 3 (P<0.05), with its practical disappearance by day 7. SF leukocyte count was 40,312±6,369 cells/mm3 in the MSU-crystals group, higher than in controls (P=0.004) and allopurinol crystal group (P=0.006). At day 7, SF leukocyte count decreased in both MSU and allopurinol crystal groups reaching the non-inflammatory range. Histologically, at day 3 intense synovial polymorphonuclear cells infiltration and MSU aggregates were identified.

CONCLUSION

The rabbit model of MSU crystal-induced acute arthritis efficiently reproduces the inflammatory, US, SF and histopathological changes of the human acute gouty attack.

Recommendations on how to ensure the safety and effectiveness of biosimilars in Latin America: a point of view

The use of biotechnology-derived medicines has significantly increased in recent decades. Although biosimilars undergo rigorous characterization as well as clinical studies to document their safety and effectiveness, they are highly complex molecules and small changes in the purification and production process of a biosimilar can have major implications in its safety and effectiveness profile. In Latin America, regulatory authorities have begun to establish well-described and standardized pathways that permit a biosimilar to gain commercial licensure. In order to be certain that a biosimilar reaches its potential in ordinary clinical use, an intensive post-licensing monitoring system must be established since it is the only means to ascertain the true similarity between the original biologic and its biosimilar. Pharmacovigilance allows national authorities to determine a drug’s performance in the marketplace. An effective tracking and pharmacovigilance system for biological medicines has many steps and processes. To aid policy makers in Latin American in addressing the many issues surrounding the establishment of an effective pharmacovigilance system, the Americas Health Foundation convened a group of experts to discuss the topic and develop recommendations for implementation. The group discussed current challenges and gaps in pharmacovigilance in Latin America, paying close attention to the major issues associated with traceability and pharmacovigilance of biosimilars following their approval. The recommendations developed should enable countries to accurately document the safety and performance of a biosimilar as experienced by patients under real-life conditions and have a significant impact on the successful implementation of pharmacovigilance of biosimilars throughout the region.