Background: Intra-articular corticosteroid injections (IACI) are a commonly used treatment for painful knee osteoarthritis (OA). Response to treatment varies the reason for which is unclear. Further there are no data concerning the impact of accuracy of injection and psychological factors including illness perceptions, pain catastrophizing and depression on outcome following IACI.Objectives: i) to undertake a systematic review looking at predictors of response to IACI in patients with symptomatic knee OA and, ii) to determine the role of psychological factors and accuracy of injection in predicting response to IACI.Methods: A systematic review was conducted using electronic databases for randomised trials and observational studies looking at predictors of response to IACI in knee and hip OA. An observational study of 141 consenting patients (105 primary OA and 36 secondary OA in the context of well controlled rheumatoid arthritis) receiving routine IACI as part of clinical care for knee OA was conducted including baseline assessment and outcome assessments at 3 and 9 weeks. Response was defined as at least 40% reduction of pain from baseline, using the Western Ontario and McMaster Universities Arthritis Index (WOMAC). Assessment included ultrasound (US) for features of synovial inflammation), radiographs, and assessment of psychological factors including the revised illness perception questionnaire (IPQR). Accuracy of injection was assessed using US. Characteristics of responders and non-responders to IACI at 3 and 9 weeks were determined using univariate statistics and significant factors entered into logistic regression models. Results: The systematic review found no consistent evidence for any disease or non-disease related predictor of response and no systematic exploration of the effects of psychological factors or accuracy of injection on treatment response. In the observational study, 83 (53%) of 141 subjects were responders to IACI at 3 weeks and 56 (44%) at 9 weeks. In univariate analysis, responders to treatment had higher scores for the IPQR domain treatment control and lower scores for IPQR consequences, depression and pain catastrophizing at both 3 and 9 weeks. Physical and patient related factors, including accuracy of injection and US features, were not associated with outcome, with the exceptions of higher baseline pain and previous experience of injection being associated with non-response at 9 weeks. In multiple regression, treatment control was the only independent predictor of response at 3 weeks. At 9 weeks, treatment control, consequences and depression were independent predictors of treatment outcome. Conclusion: In this observational study illness perceptions and depression predicted the outcome of IACI at 3 and 9 weeks. By contrast, physical factors including accuracy of injection did not influence outcome. Further work is needed to replicate these findings and elucidate mechanisms for these effects.

Although glucocorticoids are often used as an adjunct to epinephrine to treat anaphylactic shock, glucocorticoids can also be a rare cause of anaphylactic shock. Only through the administration of a challenge dose of different glucocorticoids and different substrates that glucocorticoids are delivered in can the determination be made about which glucocorticoid or accompanying solvent may be the culprit which caused the anaphylactic reaction. These challenge tests should only be performed in a controlled environment as repeat anaphylaxis is a risk, especially if the patient has a history of glucocorticoid-induced anaphylaxis.

Contexte Un objectif important de la prise en charge de l'arthrite juvénile oligoarticulaire serait d'altérer le cours de la maladie à l'aide d'une thérapie hâtive. Nous avons étudié l'effet des injections intra-articulaires de corticostéroïdes hâtives sur les chances d'atteindre un décompte d'articulation active de zéro et une maladie inactive. Méthode Les données démographiques, cliniques et thérapeutiques des patients avec oligoarthrite juvénile enrôlés dans une étude prospective longitudinale pancanadienne ont été collectées pendant 2 ans. Une injection hâtive était définie comme étant reçue dans les 3 premiers mois suivant le diagnostic. Les équations d'estimation généralisées ont été utilisées pour l'analyse statistique. Résultats Trois cent dix patients ont été inclus. Cent onze (35.8%) ont reçu une injection hâtive. Ces derniers avaient une maladie plus active lors de l'entrée dans l'étude. Les patients exposés à une injection hâtive avaient une chance similaire d'obtenir un décompte d'articulation active de zéro, OR 1.52 (IC95% 0.68-3.37), p=0.306 mais étaient significativement moins à risque d'avoir une maladie inactive, OR 0.35 (IC95% 0.14-0.88), p=0.026. Interprétation Dans cette cohorte de 310 patients avec oligoarthrite juvénile, les injections hâtives de corticostéroïdes n'ont pas mené à une probabilité plus élevée d'atteindre un décompte d'articulation active de zéro ou une maladie inactive. Des problématiques méthodologiques intrinsèques à l'utilisation de données observationnelles pour fins d'estimation d'effets thérapeutiques auraient pu biaiser les résultats. Nous ne pouvons affirmer avec certitude que les injections hâtives n'améliorent pas le décours de la maladie. Des études prospectives adressant les limitations soulevées seront requises pour clarifier la question. / Background One of the goals in oligoarticular juvenile idiopathic arthritis would be to alter the disease course with early therapy. We examined the association between early intra-articular corticosteroid injections and the achievement of an active joint count of zero and inactive disease during the first two years after study enrollment. Methods We included oligoarticular juvenile idiopathic arthritis patients enrolled into a prospective longitudinal cohort across Canada. Demographic, clinical and treatment-related information were collected. Early intra-articular corticosteroid injections was defined as having received the first injection within 3 months of diagnosis. Generalized estimating equations were used for data analysis. Results A total of 310 patients were included, of whom 111 (35.8%) received an early injection. Participants who received an early injection had more severe disease at baseline. Patients exposed to early injections had a similar chance to achieve an active joint count of zero, OR 1.52 (95%CI 0.68-3.37), p=0.306 but were significantly less likely to achieve inactive disease, OR 0.35 (95%CI 0.14-0.88), p=0.026. Interpretation In this cohort of 310 oligoarticular juvenile idiopathic arthritis patients, early intra-articular corticosteroid injections did not result in an increased risk of achieving an active joint count of zero or inactive disease. Methodological issues encountered when estimating treatment effect using observational data might have biased the estimates obtained. Firm conclusion on the inefficacy of early injections in improving outcomes in this population cannot be drawn from this study. Prospective studies addressing the limitations raised will be needed to clarify if early injections can alter the disease course.