Rheumatoid Arthritis: Johnson K

Lipani JA, Strand V, Woodworth T, Furst D, Singh G, Johnson K, Day R, Brooks P. · No affiliation provided · J Rheumatol. · Pubmed #10782801 No free full text.

This publication has no abstract.

Gardner-Medwin JM, Irwin G, Johnson K. · Department of Child Health, University of Glasgow, Royal Hospital for Sick Children, Yorkhill, Glasgow, Scotland, UK. · Ann N Y Acad Sci. · Pubmed #19250231 No free full text.

Abstract: The use of MRI in the assessment of the musculoskeletal system in children has important differences from its use in adults. Growth in children has significant impact on the epiphysis and growth plate, which are important structures in the growing child, and there are radiological features that differ from those in adults: disease may alter structures during a period of growth; the pathologies themselves are a distinct group of diseases at variance with adult arthritis and myositis, with a different spectrum of differential diagnoses; and many technical issues are different when imaging a child. These are important considerations in choosing the appropriate imaging. MRI is a powerful and valuable imaging technique in pediatric musculoskeletal pathologies, with considerable potential for future developments to enhance its role in diagnosis, management, and therapeutic intervention for these children.

Johnson K. · Radiology Department, Birmingham Children's Hospital, Steelhouse Lane, Birmingham, B4 6NH, UK. · Pediatr Radiol. · Pubmed #16741713 No free full text.

Abstract: Over the past decade there have been considerable changes in the classification and imaging of juvenile idiopathic arthritis (JIA). Radiology now has a considerable role in the management of JIA, the differential diagnosis, monitoring disease progression and detecting complications. The different imaging modalities available, their role and limitations are discussed in this article and the various disease features that the radiologist should be aware of are described. An approach to the imaging of the child with joint disease and in the monitoring of disease complications are also discussed.

Wells G, Anderson J, Boers M, Felson D, Heiberg T, Hewlett S, Johnson K, Kirwan J, Lassere M, Robinson V, Shea B, Simon L, Strand V, van Riel P, Tugwell P. · Department of Clinical Epidemiology and Community Medicine, University of Ottawa, Ottawa, Ontario, Canada. · J Rheumatol. · Pubmed #12734920 No free full text.

Abstract: The OMERACT 6 Minimal Clinically Important Difference/Low Disease Activity Workshop was organized with the aim of meeting the many challenges that exist in determining a low disease activity in rheumatoid arthritis (RA). This article presents an overview of that workshop, including results of the voting, a summary of associated discussions, recommendations, and a proposed research agenda.

Wells G, Boers M, Shea B, Anderson J, Felson D, Johnson K, Kirwan J, Lassere M, Robinson V, Simon L, Strand V, van Riel P, Tugwell P. · Department of Clinical Epidemiology and Community Medicine, University of Ottawa, Ottawa, Canada. · J Rheumatol. · Pubmed #12734918 No free full text.

Abstract: The MCID (minimal clinically important difference) module of OMERACT 5 developed a research agenda that led to the conclusion that a state of low disease activity for rheumatoid arthritis (RA) would need to be defined. To develop such a definition the various concepts and terminologies, the process for developing an operational definition, and the availability and design of longitudinal datasets for validation needed to be considered. This article describes the process of the MCID/Low Disease Activity State Workshop at OMERACT 6 to develop such a definition.

Johnson K, Gardner-Medwin J. · Department of Paediatric Radiology, Birmingham Children's Hospital, Birmingham, UK. · Clin Radiol. · Pubmed #11798203 No free full text.

Abstract: Childhood arthritis has now been reclassified into a single internationally recognized entity of juvenile idiopathic arthritis (JIA). Radiology provides an important role in the management of JIA, in helping in the differential diagnosis, monitoring disease progression and detecting complications. Traditionally, plain radiographs have been the imaging investigation of choice but magnetic resonance imaging (MRI) and ultrasound are now providing a more effective and safer alternative. The appropriate use of sequences in MR imaging is important in the early detection of joint abnormalities in JIA.

Lipani JA, Strand V, Johnson K, Woodworth T, Furst D, Singh G, Day R, Brooks P, Anonymous00241. · Department of Medicine, Standford Universiity, Palo Alto, CA, USA. · J Rheumatol. · Pubmed #11361208 No free full text.

Abstract: This paper proposes the creation of an objectively acquired reference database to more accurately characterize the incidence and longterm risk of relatively infrequent, but serious, adverse events. Such a database would be maintained longitudinally to provide for ongoing comparison with new rheumatologic drug safety databases collecting the occurrences and treatments of rare events. We propose the establishment of product-specific registries to prospectively follow a cohort of patients with rheumatoid arthritis (RA) who receive newly approved therapies. In addition, a database is required of a much larger cohort of RA patients treated with multiple second line agents of sufficient size to enable case-controlled determinations of the relative incidence of rare but serious events in the treated (registry) versus the larger disease population. The number of patients necessary for agent-specific registries and a larger patient population adequate to supply a matched case-control cohort will depend upon estimates of the detectability of an increased incidence over background. We suggest a system to carry out this proposal that will involve an umbrella organization, responsible for establishment of this large patient cohort, envisioned to be drawn from around the world.

Strand V, Lassere M, van der Heijde D, Johnson K, Boers M. · Division of Immunology, Stanford University, San Francisco, CA 94028, USA. · J Rheumatol. · Pubmed #11327271 No free full text.

Abstract: Recent randomized controlled trials of traditional and newly developed therapies provide evidence that we have interventions that potentially slow or prevent structural damage in active rheumatoid arthritis, as measured using radiography. These trials also provide a unique opportunity for exploratory data analysis to generate hypotheses apropos the pathogenesis and determinants of radiographic progression and functional disability; they also facilitate further study of the methodological issues regarding imaging measurement.

Gardner-Medwin JM, Killeen OG, Ryder CA, Bradshaw K, Johnson K. · Department of Child Health, Royal Hospital for Sick Children, Yorkhill, Glasgow, UK. · J Rheumatol. · Pubmed #16981289 No free full text.

Abstract: OBJECTIVE: A proportion of children with oligoarthritis have an aggressive disease course. Identifying these children at presentation would help guide prognosis and management. We examined if magnetic resonance imaging (MRI) of clinically unaffected joints is more sensitive than clinical assessment in identifying those at risk of developing arthritis in more than one joint. METHODS: Ten children were recruited; they had a mean age of 9.4 (range 5.2-14.2) years at presentation of a monoarthritis. MRI of a clinically unaffected knee was performed within 4 months of presentation, and was reported by 2 pediatric radiologists blinded to the clinical findings. All MR examinations included post-gadolinium sequences. Joints with clinically apparent arthritis were recorded regularly over a median of 37.0 (range 6.6-47.0) months by a median of 6.0 (range 2-8) pediatric rheumatologists blinded to the MR result. RESULTS: Four children developed arthritis in other joints over a median of 3.9 (range 3-6) months after the MRI scan; all had abnormal MRI scans at presentation. Three of these developed clinical features in the previously normal knee 4-11 months after MRI identified small joint effusions, synovial hypertrophy, and lymph node enhancement. One child developed a polyarthritis, but never developed clinical features in the imaged knee over 3.8 years of followup. Four other children had a persistent monoarthropathy with a median followup of 29.5 (range 6.6-42.0) months. All 4 had normal MRI. Two children had reactive arthritis. CONCLUSION: MRI distinguished between patients with a persistent monoarthritis and those who developed further clinical arthritis up to 1 year later. The results suggest a widespread inflammatory process may exist in children whose arthritis extends, and this has implications for our understanding of disease and the design and timing of therapeutic interventions.

McDonald K, Toms AP, Armon K, Johnson K, Marshall TJ. · Department of Radiology, Norfolk and Norwich University Hospital, Colney Lane, Norwich, Norfolk NR4 7UY, UK. · Skeletal Radiol. · Pubmed #17618432 No free full text.

Abstract: Carpal-tarsal osteolysis is a rare condition that manifests as the progressive resorption of carpal and tarsal bones in young children. The diagnosis of this condition is often difficult and delayed as the initial clinical presentation is non-specific. Radiographic changes occur gradually, are often not seen at presentation and depend on recognising loss of bone in the ossification centres of the carpus and tarsus. MRI demonstrates morphological abnormalities in the cartilaginous, as well as the osseous components, of the developing carpal and tarsal bones and therefore may be helpful in predating the radiographic changes. Ultrasound appears to contribute little to the diagnosis and may be misleading. Exclusion of other conditions, particularly juvenile idiopathic arthritis, is important in making the diagnosis. MRI can be useful in excluding an inflammatory arthropathy, and suggesting the diagnosis of carpal-tarsal osteolysis.

Nistala K, Babar J, Johnson K, Campbell-Stokes P, Foster K, Ryder C, McDonagh JE. · Paediatric Rheumatology Department, Birmingham Children's Hospital, Steelhouse Lane, Birmingham B4 6NH, UK. · Rheumatology (Oxford). · Pubmed #17158211 links to  free full text

Abstract: OBJECTIVES: To compare the diagnostic performance of clinical assessment against magnetic resonance imaging (MRI) diagnosed hip arthritis in a juvenile idiopathic arthritis (JIA) population. To determine the clinical and serological predictors of MRI diagnosed hip arthritis. METHODS: A total of 34 JIA patients with established disease (mean disease duration 6.3 yrs) had their hip MRIs scored for features of active hip arthritis and hip damage. Results were compared with clinical variables (disease subtype, history of hip pain, core outcome variables (COV)) and the clinician's assessment of active hip arthritis. RESULTS: MRI features of active hip arthritis were found in 45 hips (70%) and hip damage in 36 hips (56%). Clinical assessment had fair agreement with MRI scoring of active arthritis in patients with disease duration <4 yrs (kappa score 0.38, P = 0.045). Clinical assessment had a sensitivity of 25.7% and specificity of 91% for detecting MRI diagnosed arthritis. Of the core outcome variables only erythrocyte sedimentation rate predicted inflammation detected on MRI (r = 0.44, P = 0.014). CONCLUSIONS: The association between the clinician's assessment, core outcome variables and MRI findings in this study was limited. This indicates that clinical and laboratory findings are inadequate diagnostic tools for the assessment of hip arthritis when compared with MRI as the gold standard.

Johnson K. · Department of Radiology, Birmingham Children's Hospital, Steelhouse Lane, Birmingham B4 6NH, UK. · Pediatr Radiol. · Pubmed #12904921 No free full text.

This publication has no abstract.

Johnson K, Wittkop B, Haigh F, Ryder C, Gardner-Medwin JM. · Department of Clinical Radiology, Birmingham Children's Hospital, Birmingham, U.K. · Clin Radiol. · Pubmed #12069461 No free full text.

Abstract: AIMS: Early diagnosis of juvenile idiopathic arthritis (JIA) facilitates earlier more aggressive therapy, and improved outcome. Recognition of the features of early, untreated JIA on magnetic resonance imaging (MRI) will improve disease detection and expedite treatment. This study aims to highlight the relevant MRI features. METHODS: MRI examinations of the knee joint were performed on 11 children with clinically confirmed, early, untreated JIA. The MRI images were obtained at a mean of 2 months after symptom onset and independently evaluated by two consultant paediatric radiologists. RESULTS: Abnormalities were found on all MRI examinations. Synovial hypertrophy, joint effusions, popliteal lymph nodes and soft tissue swelling were present in all patients. Gadolinium DTPA enhancement improved the detection of synovial hyperplasia. Metaphyseal splaying and condylar overgrowth were seen in five cases (41%), oedema of the lateral collateral ligament in two cases (18%) and superficial cartilage thinning in one case. Bony erosions and deep cartilage destruction were not demonstrated. CONCLUSION: MRI of the knee joint identifies early joint changes which are distinct from those in later disease. The presence of these features should alert the radiologist to the possible diagnosis of JIA and post gadolinium DTPA sequences should be performed. Gadolinium DPTA enhancement increases the sensitivity for the detection of inflammatory changes in JIA.

Lassere MN, van der Heijde D, Johnson K, Bruynesteyn K, Molenaar E, Boonen A, Verhoeven A, Emery P, Boers M. · Department of Rheumatology, St George Hospital, NSW, Sydney, Australia. · J Rheumatol. · Pubmed #11327275 No free full text.

Abstract: The smallest detectable difference (SDD) reflects that component of a measure statistically attributable to error from the measurement process itself. As such it is an irreducible component of the inherent variability in measurements in clinical trials and will affect their design, whether randomized or observational. Even though the application of the SDD concept to assaying radiographs in rheumatoid arthritis is relatively new and not well understood, systematic work on the influences of radiographic SDD can be done. This report describes the effects of a number of clinical aspects of the disease and operational aspects of trials on the values of the SDD of radiographic progression data. We show that if conditions affecting SDD are known and kept constant across datasets, the SDD of radiological progression from one study may be generalizable to other studies. However, if any one condition varies, the SDD is distinctly unrobust and cannot be generalized to other studies.

Johnson K. · No affiliation provided · J Rheumatol. · Pubmed #10685832 No free full text.

Abstract: Since medicine remains largely empirical, clinical knowledge about therapy is derived primarily from experiments designed to control confounders that use inferential techniques applied to the null hypothesis model. On a public health scale, health agencies need to assess the evidentiary weight supplied for new therapies to make approval decisions. In the field of rheumatoid arthritis (RA), there are additional analytic challenges such as designation of endpoints or missing data. The intellectual architecture that underpins these exercises continues to evolve, and recently the US Food and Drug Administration released an RA Guidance Document to describe some aspects of these exercises. This article focuses on the use of measurements of radiographic endpoints in particular as an element in the evidentiary portrayal of therapeutic efficacy in RA.

Davis PJ, Hackett J, Johnson K, McDonagh JE. · No affiliation provided · Ann Rheum Dis. · Pubmed #16284343 links to  free full text

This publication has no abstract.