Tocilizumab in giant cell arteritis: an update for the clinician.

PURPOSE OF REVIEW: The recent approval of tocilizumab (TCZ) for the treatment of giant cell arteritis (GCA) has changed the landscape for management of this disease. Herein, we review recent literature addressing practical questions for the clinician regarding the use of TCZ in GCA. We evaluate efficacy of TCZ across different disease phenotypes, optimal dosing and formulation, treatment-related toxicity, recommendations for monitoring disease, and duration of therapy. RECENT FINDINGS: Post-hoc analyses of a large clinical trial and real-world data suggest efficacy of TCZ across various disease phenotypes in GCA, and support use of weekly subcutaneous dosing over every-other-week dosing. More data are needed to guide duration of TCZ therapy, optimal disease activity monitoring in patients treated with TCZ, and to speak to efficacy in GCA with large vessel involvement. SUMMARY: TCZ has added valuably to the treatment arsenal in GCA, though more data are needed to guide optimal use of the drug.

Rituximab versus azathioprine for maintenance of remission for patients with ANCA-associated vasculitis and relapsing disease: an international randomised controlled trial.

OBJECTIVE: Following induction of remission with rituximab in anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) relapse rates are high, especially in patients with history of relapse. Relapses are associated with increased exposure to immunosuppressive medications, the accrual of damage and increased morbidity and mortality. The RITAZAREM trial compared the efficacy of repeat-dose rituximab to daily oral azathioprine for prevention of relapse in patients with relapsing AAV in whom remission was reinduced with rituximab. METHODS: RITAZAREM was an international randomised controlled, open-label, superiority trial that recruited 188 patients at the time of an AAV relapse from 29 centres in seven countries between April 2013 and November 2016. All patients received rituximab and glucocorticoids to reinduce remission. Patients achieving remission by 4 months were randomised to receive rituximab intravenously (1000 mg every 4 months, through month 20) (85 patients) or azathioprine (2 mg/kg/day, tapered after month 24) (85 patients) and followed for a minimum of 36 months. The primary outcome was time to disease relapse (either major or minor relapse). RESULTS: Rituximab was superior to azathioprine in preventing relapse: HR 0.41; 95% CI 0.27 to 0.61, p<0.001. 19/85 (22%) patients in the rituximab group and 31/85 (36%) in the azathioprine group experienced at least one serious adverse event during the treatment period. There were no differences in rates of hypogammaglobulinaemia or infection between groups. CONCLUSIONS: Following induction of remission with rituximab, fixed-interval, repeat-dose rituximab was superior to azathioprine for preventing disease relapse in patients with AAV with a prior history of relapse. TRIAL REGISTRATION NUMBER: NCT01697267; ClinicalTrials.gov identifier.

Therapeutic advances in eosinophilic granulomatosis with polyangiitis.

PURPOSE OF REVIEW: In recent years, therapeutic advances in eosinophilic granulomatosis with polyangiitis (EGPA) have changed our treatment paradigm. This review will summarize and discuss updates in management of EGPA, with a particular focus on biologic therapies. RECENT FINDINGS: The anti-interleukin (IL)-5 agent mepolizumab (the first FDA-approved drug specifically for EGPA) is effective in induction and maintenance of remission particularly in patients with predominantly asthma and allergic manifestations, though efficacy in ANCA-positive, vasculitic disease is unclear; additional anti-IL-5 agents are under study. Rituximab is currently recommended for remission induction in severe disease, particularly in ANCA-positive patients with vasculitic manifestations, though the supportive evidence is mostly observational. Evidence supporting use of traditional DMARDs and other biologic agents such as omalizumab remains limited and observational. SUMMARY: Although management of this heterogeneous disease remains challenging and unanswered questions remain, advances in biologics (particularly anti-IL-5 agents and an evolving interest in rituximab) have expanded our treatment armamentarium in EGPA.

Rituximab as therapy to induce remission after relapse in ANCA-associated vasculitis.

OBJECTIVES: Evaluation of rituximab and glucocorticoids as therapy to induce remission after relapse in ANCA-associated vasculitis (AAV) in a prospective observational cohort of patients enrolled into the induction phase of the RITAZAREM trial. METHODS: Patients relapsing with granulomatosis with polyangiitis or microscopic polyangiitis were prospectively enrolled and received remission-induction therapy with rituximab (4×375 mg/m2) and a higher or lower dose glucocorticoid regimen, depending on physician choice: reducing from either 1 mg/kg/day or 0.5 mg/kg/day to 10 mg/day by 4 months. Patients in this cohort achieving remission were subsequently randomised to receive one of two regimens to prevent relapse. RESULTS: 188 patients were studied: 95/188 (51%) men, median age 59 years (range 19-89), prior disease duration 5.0 years (range 0.4-34.5). 149/188 (79%) had previously received cyclophosphamide and 67/188 (36%) rituximab. 119/188 (63%) of relapses had at least one major disease activity item, and 54/188 (29%) received the higher dose glucocorticoid regimen. 171/188 (90%) patients achieved remission by 4 months. Only six patients (3.2% of the study population) did not achieve disease control at month 4. Four patients died in the induction phase due to pneumonia (2), cerebrovascular accident (1), and active vasculitis (1). 41 severe adverse events occurred in 27 patients, including 13 severe infections. CONCLUSIONS: This large prospective cohort of patients with relapsing AAV treated with rituximab in conjunction with glucocorticoids demonstrated a high level of efficacy for the reinduction of remission in patients with AAV who have relapsed, with a similar safety profile to previous studies.

Update on maintenance therapy for granulomatosis with polyangiitis and microscopic polyangiitis.

PURPOSE OF REVIEW: The antineutrophilic cytoplasmic antibody (ANCA)-associated vasculitides are a group of rare systemic diseases. The past several years have seen major therapeutic advances in the treatment of granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). The success rate in induction of remission is high, but reducing the high incidence of relapses remains a therapeutic challenge. RECENT FINDINGS: Studies have shown no improvement in relapse rates in GPA and MPA over the past 2 decades. This has prompted a recent focus on therapeutic strategies to maintain remission in these relapsing diseases. Low-dose rituximab (RTX) at fixed intervals has been shown superior to azathioprine for maintenance of remission. Despite this advance, longer follow-up periods have shown late-stage relapses with withdrawal of therapy suggesting a possible need for longer treatment regimens. Evaluation of prognostic indicators is also helpful in stratifying patients who might be more likely to relapse or to respond to a particular therapy. SUMMARY: Results from recent research have significantly advanced our approach to prevention of relapses in GPA and MPA. Newer maintenance agents have shown benefit in maintenance of remission and relapse-free survival.

2017 American College of Rheumatology/American Association of Hip and Knee Surgeons Guideline for the Perioperative Management of Antirheumatic Medication in Patients With Rheumatic Diseases Undergoing Elective Total Hip or Total Knee Arthroplasty.

OBJECTIVE: This collaboration between the American College of Rheumatology and the American Association of Hip and Knee Surgeons developed an evidence-based guideline for the perioperative management of antirheumatic drug therapy for adults with rheumatoid arthritis (RA), spondyloarthritis (SpA) including ankylosing spondylitis and psoriatic arthritis, juvenile idiopathic arthritis (JIA), or systemic lupus erythematosus (SLE) undergoing elective total hip (THA) or total knee arthroplasty (TKA). METHODS: A panel of rheumatologists, orthopedic surgeons specializing in hip and knee arthroplasty, and methodologists was convened to construct the key clinical questions to be answered in the guideline. A multi-step systematic literature review was then conducted, from which evidence was synthesized for continuing versus withholding antirheumatic drug therapy and for optimal glucocorticoid management in the perioperative period. A Patient Panel was convened to determine patient values and preferences, and the Grading of Recommendations Assessment, Development and Evaluation methodology was used to rate the quality of evidence and the strength of recommendations, using a group consensus process through a convened Voting Panel of rheumatologists and orthopedic surgeons. The strength of the recommendation reflects the degree of certainty that benefits outweigh harms of the intervention, or vice versa, considering the quality of available evidence and the variability in patient values and preferences. RESULTS: The guideline addresses the perioperative use of antirheumatic drug therapy including traditional disease-modifying antirheumatic drugs, biologic agents, tofacitinib, and glucocorticoids in adults with RA, SpA, JIA, or SLE who are undergoing elective THA or TKA. It provides recommendations regarding when to continue, when to withhold, and when to restart these medications, and the optimal perioperative dosing of glucocorticoids. The guideline includes 7 recommendations, all of which are conditional and based on low- or moderate-quality evidence. CONCLUSION: This guideline should help decision-making by clinicians and patients regarding perioperative antirheumatic medication management at the time of elective THA or TKA. These conditional recommendations reflect the paucity of high-quality direct randomized controlled trial data.

Hypovitaminosis D is a predictor of aromatase inhibitor musculoskeletal symptoms.

The aromatase inhibitor (AI)-associated musculoskeletal (MSK) pain symptoms are often debilitating and limit compliance with this important hormonal breast cancer therapy. The etiology of this syndrome is unknown. Hypovitaminosis D has been suggested as a possible risk factor for the development of MSK symptoms in women starting AIs. The objective of this substudy was to define the prevalence of low 25(OH)D in this population, to assess risk of low levels on developing pain and to define a target therapeutic goal for 25(OH)D in this population. This analysis was part of a 6-month prospective cohort study examining the MSK side effects of adjuvant AI therapy in postmenopausal women. Patients were evaluated by a rheumatologist with a joint examination, had 25(OH)D levels measured and completed quality of life questionnaires at baseline, 3 and 6 months. Symptomatic patients were defined as those that self-reported new or worsening MSK symptoms. Of 52 patients, 28 (54%) were symptomatic, and two (3.8%) stopped AIs due to MSK ailments. Thirteen patients had objective evidence of tendonitis on rheumatologic examination. Thirty-three percent of all subjects had baseline 25(OH)D levels <40 ng/mL, 19.2% had levels <30 ng/mL and 5.8% had levels <20 ng/mL. Symptomatic patients were more likely to have had baseline levels below 40 ng/mL, compared with asymptomatic patients (46.4% versus 16.7%, p = 0.037). In multivariate regression analyses, levels <40 ng/mL were associated with developing objective tenosynovitis (p = 0.033) but not with developing nonspecific myalgias. Our findings suggest hypovitaminosis D may be contributing to the AI-associated MSK pain syndrome and in particular to the development of tendonitis. Repletion to 25(OH)D levels >40 ng/mL is advisable. Further research should be carried out on identifying additional modifiable risk factors for this syndrome.

Real-World Experience With Avacopan in Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis.

Introduction: Postmarketing data on outcomes of avacopan use in antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) are lacking. Methods: We performed a multicenter retrospective analysis of 92 patients with newly diagnosed or relapsing AAV who received therapy with avacopan. The coprimary outcome measures were clinical remission at 26 and 52 weeks. We use descriptive statistics and univariate logistic regression to assess outcomes and predictors of remission, respectively. Results: Of the 92 patients, 23% (n = 21) had a baseline estimated glomerular filtration rate (eGFR) < 15 ml/min per 1.73 m2 and 10% on kidney replacement therapy at baseline. Among those with kidney involvement, mean (SD) enrollment eGFR was 33 (27) ml/min per 1.73 m2 with a mean (SD) change of +12 (25) and +20 (23) ml/min per 1.73 m2 at weeks 26 and 52, respectively. In addition to avacopan, 47% of patients received combination therapy of rituximab and low-dose cyclophosphamide, and 14% of patients received plasma exchange (PLEX). After induction, the median (interquartile range [IQR]) time to start avacopan was 3.6 (2.1-7.7) weeks, and the median time to discontinue prednisone after starting avacopan was 5.6 (3.3-9.5) weeks. Clinical remission was achieved in 90% of patients at week 26 and 84% of patients at week 52. Of the patients, 20% stopped avacopan due to adverse events, with the most common being elevated serum aminotransferases (4.3%). Conclusion: A high rate of remission and an acceptable safety profile were observed with the use of avacopan in the treatment of AAV in this postmarketing analysis, including the populations excluded from the ADVOCATE trial.

Methotrexate versus leflunomide in rheumatoid arthritis: what is new in 2011?

PURPOSE OF REVIEW: To review the recent efficacy and safety data comparing methotrexate (MTX) and leflunomide (LEF) monotherapy, in combination with biologic therapies and in combination with each other. RECENT FINDINGS: MTX is the 'anchor drug' in all rheumatoid arthritis treatment strategies. Patients with contraindications to or intolerance of this drug pose a challenge to the treating physician. Recent studies have re-examined LEF as an alternative to MTX and demonstrated comparable clinical and radiographic efficacy both as monotherapy and in combination with certain biologic agents (tumor necrosis factor inhibitors and rituximab). Safety data, however, are less conclusive. Though some studies have shown greater withdrawal rates with LEF, the incidence of infection and elevated transaminases have been comparable. There are few new data examining the previously demonstrated added benefit of combination MTX+LEF over either alone. The safety profile of this combination, however, has been re-examined in several studies, with conflicting results. Although two meta-analyses and two small retrospective studies have demonstrated a safety profile similar to that of MTX monotherapy, data from a large population study suggested a greater degree of hepatotoxicity with combination. SUMMARY: LEF offers an alternative with comparable efficacy to MTX as both monotherapy and, as preliminary data suggest, in combination with certain biologics agents. Addition of LEF to MTX in rheumatoid arthritis patients who have failed MTX monotherapy has added therapeutic benefit. Safety data on LEF compared to MTX are less conclusive. All patients on LEF, and particularly those on combined LEF+MTX, should be monitored closely for hepatotoxicity.

Safety and efficacy of abatacept in early diffuse cutaneous systemic sclerosis (ASSET): open-label extension of a phase 2, double-blind randomised trial.

BACKGROUND: Abatacept was well tolerated by patients with early diffuse cutaneous systemic sclerosis in a phase 2, double-blind randomised trial, with potential efficacy at 12 months. We report here the results of an open-label extension for 6 months. METHODS: Patients (aged ≥18 years) with diffuse cutaneous systemic sclerosis of less than 3 years' duration from their first non-Raynaud's symptom were enrolled into the ASSET trial (A Study of Subcutaneous Abatacept to Treat DiffuseCutaneous Systemic Sclerosis), which is a double-blind trial at 22 sites in Canada, the UK, and the USA. Aftercompletion of 12 months of treatment with either abatacept or placebo, patients received a further 6 months ofabatacept (125 mg subcutaneous every week) in an open-label extension. The primary endpoint of the double-blind trial was modified Rodnan Skin Score (mRSS) at 12 months, which was reassessed at 18 months in the open-label extension. The primary analysis included all participants who completed the double-blind trial and received at least one dose of open-label treatment (modified intention to treat). This trial is registered with ClinicalTrials.gov, NCT02161406. FINDINGS: Between Sept 22, 2014, and March 15, 2017, 88 participants were randomly allocated in the double-blind trial either abatacept (n=44) or placebo (44); 32 patients from each treatment group completed the 6-month open-labelextension. Among patients assigned abatacept, a mean improvement from baseline in mRSS was noted at 12 months (-6·6 [SD 6·4]), with further improvement seen during the open-label extension period (-9·8 [8·1] at month 18). Participants assigned placebo had a mean improvement from baseline in mRSS at 12 months (-3·7 [SD 7·6]), with a further improvement at month 18 (-6·3 [9·3]). Infections during the open-label extension phase occurred in nine patients in the placebo-abatacept group (12 adverse events, one serious adverse event) and in 11 patients in theabatacept-abatacept group (14 adverse events, one serious adverse event). Two deaths occurred during the 12-month double-blind period in the abatacept group, which were related to scleroderma renal crisis; no deaths were recorded during the open-label extension. INTERPRETATION: During the 6-month open-label extension, no new safety signals for abatacept were identified in the treatment of diffuse cutaneous systemic sclerosis. Clinically meaningful improvements in mRSS and other outcome measures were observed in both the abatacept and placebo groups when patients transitioned to open-label treatment. These data support further studies of abatacept in diffuse cutaneous systemic sclerosis. FUNDING: Bristol-Myers Squibb and National Institutes of Health.

Abatacept in Early Diffuse Cutaneous Systemic Sclerosis: Results of a Phase II Investigator-Initiated, Multicenter, Double-Blind, Randomized, Placebo-Controlled Trial.

OBJECTIVE: T cells play a key role in the pathogenesis of early systemic sclerosis. This study was undertaken to assess the safety and efficacy of abatacept in patients with diffuse cutaneous systemic sclerosis (dcSSc). METHODS: In this 12-month, randomized, double-blind, placebo-controlled trial, participants were randomized 1:1 to receive either subcutaneous abatacept 125 mg or matching placebo, stratified by duration of dcSSc. Escape therapy was allowed at 6 months for worsening disease. The coprimary end points were change in the modified Rodnan skin thickness score (MRSS) compared to baseline and safety over 12 months. Differences in longitudinal outcomes were assessed according to treatment using linear mixed models, with outcomes censored after initiation of escape therapy. Skin tissue obtained from participants at baseline was classified into intrinsic gene expression subsets. RESULTS: Among 88 participants, the adjusted mean change in the MRSS at 12 months was -6.24 units for those receiving abatacept and -4.49 units for those receiving placebo, with an adjusted mean treatment difference of -1.75 units (P = 0.28). Outcomes for 2 secondary measures (Health Assessment Questionnaire disability index and a composite measure) were clinically and statistically significantly better with abatacept. The proportion of subjects in whom escape therapy was needed was higher in the placebo group relative to the abatacept group (36% versus 16%). In the inflammatory and normal-like skin gene expression subsets, decline in the MRSS over 12 months was clinically and significantly greater in the abatacept group versus the placebo group (P < 0.001 and P = 0.03, respectively). In the abatacept group, adverse events occurred in 35 participants versus 40 participants in the placebo group, including 2 deaths and 1 death, respectively. CONCLUSION: In this phase II trial, abatacept was well-tolerated, but change in the MRSS was not statistically significant. Secondary outcome measures, including gene expression subsets, showed evidence in support of abatacept. These data should be confirmed in a phase III trial.

2017 American College of Rheumatology/American Association of Hip and Knee Surgeons Guideline for the Perioperative Management of Antirheumatic Medication in Patients With Rheumatic Diseases Undergoing Elective Total Hip or Total Knee Arthroplasty.

OBJECTIVE: This collaboration between the American College of Rheumatology and the American Association of Hip and Knee Surgeons developed an evidence-based guideline for the perioperative management of antirheumatic drug therapy for adults with rheumatoid arthritis (RA), spondyloarthritis (SpA) including ankylosing spondylitis and psoriatic arthritis, juvenile idiopathic arthritis (JIA), or systemic lupus erythematosus (SLE) undergoing elective total hip (THA) or total knee arthroplasty (TKA). METHODS: A panel of rheumatologists, orthopedic surgeons specializing in hip and knee arthroplasty, and methodologists was convened to construct the key clinical questions to be answered in the guideline. A multi-step systematic literature review was then conducted, from which evidence was synthesized for continuing versus withholding antirheumatic drug therapy and for optimal glucocorticoid management in the perioperative period. A Patient Panel was convened to determine patient values and preferences, and the Grading of Recommendations Assessment, Development and Evaluation methodology was used to rate the quality of evidence and the strength of recommendations, using a group consensus process through a convened Voting Panel of rheumatologists and orthopedic surgeons. The strength of the recommendation reflects the degree of certainty that benefits outweigh harms of the intervention, or vice versa, considering the quality of available evidence and the variability in patient values and preferences. RESULTS: The guideline addresses the perioperative use of antirheumatic drug therapy including traditional disease-modifying antirheumatic drugs, biologic agents, tofacitinib, and glucocorticoids in adults with RA, SpA, JIA, or SLE who are undergoing elective THA or TKA. It provides recommendations regarding when to continue, when to withhold, and when to restart these medications, and the optimal perioperative dosing of glucocorticoids. The guideline includes 7 recommendations, all of which are conditional and based on low- or moderate-quality evidence. CONCLUSION: This guideline should help decision-making by clinicians and patients regarding perioperative antirheumatic medication management at the time of elective THA or TKA. These conditional recommendations reflect the paucity of high-quality direct randomized controlled trial data.

2017 American College of Rheumatology/American Association of Hip and Knee Surgeons Guideline for the Perioperative Management of Antirheumatic Medication in Patients With Rheumatic Diseases Undergoing Elective Total Hip or Total Knee Arthroplasty.

OBJECTIVE: This collaboration between the American College of Rheumatology and the American Association of Hip and Knee Surgeons developed an evidence-based guideline for the perioperative management of antirheumatic drug therapy for adults with rheumatoid arthritis (RA), spondyloarthritis (SpA) including ankylosing spondylitis and psoriatic arthritis, juvenile idiopathic arthritis (JIA), or systemic lupus erythematosus (SLE) undergoing elective total hip (THA) or total knee arthroplasty (TKA). METHODS: A panel of rheumatologists, orthopedic surgeons specializing in hip and knee arthroplasty, and methodologists was convened to construct the key clinical questions to be answered in the guideline. A multi-step systematic literature review was then conducted, from which evidence was synthesized for continuing versus withholding antirheumatic drug therapy and for optimal glucocorticoid management in the perioperative period. A Patient Panel was convened to determine patient values and preferences, and the Grading of Recommendations Assessment, Development and Evaluation methodology was used to rate the quality of evidence and the strength of recommendations, using a group consensus process through a convened Voting Panel of rheumatologists and orthopedic surgeons. The strength of the recommendation reflects the degree of certainty that benefits outweigh harms of the intervention, or vice versa, considering the quality of available evidence and the variability in patient values and preferences. RESULTS: The guideline addresses the perioperative use of antirheumatic drug therapy including traditional disease-modifying antirheumatic drugs, biologic agents, tofacitinib, and glucocorticoids in adults with RA, SpA, JIA, or SLE who are undergoing elective THA or TKA. It provides recommendations regarding when to continue, when to withhold, and when to restart these medications, and the optimal perioperative dosing of glucocorticoids. The guideline includes 7 recommendations, all of which are conditional and based on low- or moderate-quality evidence. CONCLUSION: This guideline should help decision-making by clinicians and patients regarding perioperative antirheumatic medication management at the time of elective THA or TKA. These conditional recommendations reflect the paucity of high-quality direct randomized controlled trial data.

Identification of Functional and Expression Polymorphisms Associated With Risk for Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis.

OBJECTIVE: To identify risk alleles relevant to the causal and biologic mechanisms of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: A genome-wide association study and subsequent replication study were conducted in a total cohort of 1,986 cases of AAV (patients with granulomatosis with polyangiitis [Wegener's] [GPA] or microscopic polyangiitis [MPA]) and 4,723 healthy controls. Meta-analysis of these data sets and functional annotation of identified risk loci were performed, and candidate disease variants with unknown functional effects were investigated for their impact on gene expression and/or protein function. RESULTS: Among the genome-wide significant associations identified, the largest effect on risk of AAV came from the single-nucleotide polymorphism variants rs141530233 and rs1042169 at the HLA-DPB1 locus (odds ratio [OR] 2.99 and OR 2.82, respectively) which, together with a third variant, rs386699872, constitute a triallelic risk haplotype associated with reduced expression of the HLA-DPB1 gene and HLA-DP protein in B cells and monocytes and with increased frequency of complementary proteinase 3 (PR3)-reactive T cells relative to that in carriers of the protective haplotype. Significant associations were also observed at the SERPINA1 and PTPN22 loci, the peak signals arising from functionally relevant missense variants, and at PRTN3, in which the top-scoring variant correlated with increased PRTN3 expression in neutrophils. Effects of individual loci on AAV risk differed between patients with GPA and those with MPA or between patients with PR3-ANCAs and those with myeloperoxidase-ANCAs, but the collective population attributable fraction for these variants was substantive, at 77%. CONCLUSION: This study reveals the association of susceptibility to GPA and MPA with functional gene variants that explain much of the genetic etiology of AAV, could influence and possibly be predictors of the clinical presentation, and appear to alter immune cell proteins and responses likely to be key factors in the pathogenesis of AAV.

Cogan and Behcet syndromes.

Cogan and Behcet syndromes are considered large vessel vasculitides. Both are rare diseases, with varied clinical manifestations affecting multiple organ systems. Although both have hallmark symptoms (ocular and vestibuloauditory inflammation in Cogan syndrome and aphthous ulcers in Behcet syndrome), neither has confirmatory diagnostic testing. Delayed diagnosis can result in poor outcomes. In both syndromes, large vessel arterial inflammation may result in severe morbidity and mortality. Treatment strategies in both syndromes vary based on organ system involvement and severity of manifestations. In this article, the epidemiology, proposed pathogenesis, manifestations, and the most current treatment paradigms for these syndromes are reviewed.

Defining the aromatase inhibitor musculoskeletal syndrome: a prospective study.

OBJECTIVE: To define the musculoskeletal syndrome associated with use of aromatase inhibitors (AIs), specifically, to describe its incidence, time to onset, risk factors, and clinical presentation. METHODS: Postmenopausal women with hormone-sensitive, nonmetastatic breast cancer starting AI therapy were enrolled in this prospective cohort study. They underwent complete rheumatologic evaluation and contrast-enhanced magnetic resonance imaging (MRI) of the hands and wrists prior to starting AI, at 3 and 6 months. The primary outcome was change in grip strength. RESULTS: Twenty-eight (54%) of 52 women reported new or worsening musculoskeletal symptoms. Two discontinued AIs due to pain. Mean time to symptom onset was 6 weeks (range 2-18 weeks), and 75% of symptomatic patients developed symptoms by 8 weeks. Later-stage cancer and worse quality of life (QOL) pretreatment were significantly associated with symptom development. Sixty-eight percent of symptomatic subjects had involvement of the hands; however, there was no difference in the mean change in grip strength (-2.9 kg versus -1.3 kg; P = 0.6). Among symptomatic subjects, 46% had evidence of focal tenosynovitis of the hands and feet on examination. Although some symptomatic subjects had new MRI abnormalities, Rheumatoid Arthritis Magnetic Resonance Imaging Scoring did not significantly change. CONCLUSION: The incidence of AI-associated musculoskeletal syndrome is more than 50%, with most women developing symptoms by 8 weeks. The key finding in symptomatic women was focal tenosynovitis of the hands and feet, without evidence of autoimmune disease or systemic inflammation. Later-stage cancer and poorer QOL were predictive of symptom development.