Julie Drouin

OBJECTIVE: To describe successful therapeutic strategies in statin-induced anti-HMGCR myopathy. METHODS: Retrospective data from a cohort of 55 patients with statin-induced anti-HMGCR myopathy, sequentially stratified by the presence of proximal weakness, early remission, and corticosteroid and IVIG use at treatment induction, were analyzed for optimal successful induction and maintenance of remission strategies. RESULTS: A total of 14 patients achieved remission with a corticosteroid-free induction strategy (25%). In 41 patients treated with corticosteroids, only 4 patients (10%) failed an initial triple steroid/IVIG/steroid-sparing immunosuppressant (SSI) induction strategy. Delay in treatment initiation was independently associated with lower odds of successful maintenance with immunosuppressant monotherapy (OR 0.92, 95% CI 0.85 to 0.97, P = 0.015). While 22 patients (40%) presented with normal strength, only 9 had normal strength at initiation of treatment. CONCLUSION: While corticosteroid-free treatment of anti-HMGCR myopathy is now a safe option in selected cases, initial triple steroid/IVIG/SSI was very efficacious in induction. Delays in treatment initiation and, as a corollary, delays in achieving remission decrease the odds of achieving successful maintenance with an SSI alone. Avoiding such delays, most notably in patients with normal strength, may reset the natural history of anti-HMGCR myopathy from a refractory entity to a treatable disease.

OBJECTIVE: To determine through a systematic literature search the predictors of clinical response and radiographic progression in adult patients with rheumatoid arthritis (RA) treated with methotrexate (MTX) monotherapy. METHODS: A systematic literature search using Medline, Embase, and the Cochrane Central Register of Controlled Trials, in May 2008, and review of abstracts of the annual congresses of the American College of Rheumatology (2006-2007) and the European League Against Rheumatism (2002-2007) was performed, as part of a national initiative to develop guidelines for the use of MTX in RA. RESULTS: Nine studies fulfilled the criteria set for this literature search. Male sex, low disease activity measured by composite scores (DAS or SDAI), and nonutilization of prior DMARD were predictive of good clinical response to MTX. Patients with early RA who are rheumatoid factor-positive and smokers tend to have lower response. However, this last association has not been found for patients with established disease. High disease activity before introduction of MTX monotherapy and higher activity during followup at 3 months is a predictor of more severe radiographic progression. CONCLUSION: Among factors found to be predictive of clinical and radiographic outcomes of patients with RA treated with MTX, no factor was found to have a high predictive value. Variability in efficacy measures and statistical tests made it difficult to compare results. Followup of disease activity after 3 to 6 months of treatment seems to be a better and more useful predictor than baseline patient characteristics.

OBJECTIVE: To develop recommendations for the use of methotrexate (MTX) in patients with rheumatoid arthritis. METHODS: Canadian rheumatologists who participated in the international 3e Initiative in Rheumatology (evidence, expertise, exchange) in 2007-2008 formulated 5 unique Canadian questions. A bibliographic team systematically reviewed the relevant literature on these 5 topics. An expert committee consisting of 26 rheumatologists from across Canada was convened, and a set of recommendations was proposed based on the results of systematic reviews combined with expert opinions using a nominal group consensus process. RESULTS: The 5 questions addressed drug interactions, predictors of response, strategies to reduce non-serious side effects, variables to assess clinical response, and incorporating patient preference into decision-making. The systematic review retrieved 93 pertinent articles; this evidence was presented to the expert committee during the interactive workshop. After extensive discussion and voting, a total of 9 recommendations were formulated: 2 on drug interactions, 1 on predictors of response, 2 on strategies to reduce non-serious side effects, 3 on variables to assess clinical response, and 1 on incorporating patient preferences into decision-making. The level of evidence and the strength of recommendations are reported. Agreement among panelists ranged from 85% to 100%. CONCLUSION: Nine recommendations pertaining to the use of MTX in daily practice were developed using an evidence-based approach followed by expert/physician consensus with high level of agreement.

The general aim of this study was to evaluate the disease spectrum in patients presenting with a pure polymyositis (pPM) phenotype. Specific objectives were to characterize clinical features, autoantibodies (aAbs), and membrane attack complex (MAC) in muscle biopsies of patients with treatment-responsive, statin-exposed necrotizing autoimmune myositis (NAM). Patients from the Centre hospitalier de l'Université de Montréal autoimmune myositis (AIM) Cohort with a pPM phenotype, response to immunosuppression, and follow-up ≥3 years were included. Of 17 consecutive patients with pPM, 14 patients had a NAM, of whom 12 were previously exposed to atorvastatin (mean 38.8 months). These 12 patients were therefore suspected of atorvastatin-induced AIM (atorAIM) and selected for study. All had aAbs to 3-hydroxy-3-methylglutaryl coenzyme A reductase, and none had overlap aAbs, aAbs to signal recognition particle, or cancer. Three stages of myopathy were recognized: stage 1 (isolated serum creatine kinase [CK] elevation), stage 2 (CK elevation, normal strength, and abnormal electromyogram [EMG]), and stage 3 (CK elevation, proximal weakness, and abnormal EMG). At diagnosis, 10/12 (83%) patients had stage 3 myopathy (mean CK elevation: 7247 U/L). The presenting mode was stage 1 in 6 patients (50%) (mean CK elevation: 1540 U/L), all of whom progressed to stage 3 (mean delay: 37 months) despite atorvastatin discontinuation. MAC deposition was observed in all muscle biopsies (isolated sarcolemmal deposition on non-necrotic fibers, isolated granular deposition on endomysial capillaries, or mixed pattern). Oral corticosteroids alone failed to normalize CKs and induce remission. Ten patients (83%) received intravenous immune globulin (IVIG) as part of an induction regimen. Of 10 patients with ≥1 year remission on stable maintenance therapy, IVIG was needed in 50%, either with methotrexate (MTX) monotherapy or combination immunosuppression. In the remaining patients, MTX monotherapy or combination therapy maintained remission without IVIG. AtorAIM emerged as the dominant entity in patients with a pPM phenotype and treatment-responsive myopathy. Isolated CK elevation was the mode of presentation of atorAIM. The new onset of isolated CK elevation on atorvastatin and persistent CK elevation on statin discontinuation should raise early suspicion for atorAIM. Statin-induced AIM should be included in the differential diagnosis of asymptomatic hyperCKemia. Three patterns of MAC deposition, while nonpathognomonic, were pathological clues to atorAIM. AtorAIM was uniformly corticosteroid resistant but responsive to IVIG as induction and maintenance therapy.

Intensive plasma exchange therapy with fresh-frozen plasma as the replacement fluid was used to manage ten patients, five with acute and five with chronic immune thrombocytopenic purpura (ITP). Therapy was started because of severe hemorrhage (1 case), failure to respond to steroid therapy (6 cases), or steroid dependence (3 cases). After a median of four exchanges over 6 days (median total volume removed, 11.7 liters), initial responses, defined as a platelet count greater than 100,000 per microliter at the end of the exchange series, were observed in 80 percent of the patients treated. Two adolescents, ages 16 and 17 years, with chronic ITP failed to respond to plasma exchange therapy and subsequently responded to splenectomy. Prolonged remissions of 9 months and greater than 2 years were observed in two patients with acute ITP; in patients with chronic ITP, no prolonged remissions occurred. Neither pre-exchange levels of platelet-associated immunoglobulin G (PAIgG) nor circulating immune complexes predicted the response to plasma exchange, although serially determined PAIgG levels correlated with the severity of ITP and response, or lack of response, to plasma exchange. We conclude that intensive plasma exchange merits further study in patients with acute ITP unresponsive to steroid therapy to determine if the need for splenectomy is reduced. In selected patients with chronic ITP, exchange therapy may provide short-term adjunctive benefit.