Statin-induced focal myositis of the upper extremity. A report of two cases

Statin use and longitudinal changes in quantitative MRI-based biomarkers of thigh muscle quality: data from Osteoarthritis Initiative

OBJECTIVE

To assess whether changes in MRI-based measures of thigh muscle quality associated with statin use in participants with and without/at-risk of knee osteoarthritis.

METHODS

This retrospective cohort study used data from the Osteoarthritis Initiative study. Statin users and non-users were matched for relevant covariates using 1:1 propensity-score matching. Participants were further stratified according to baseline radiographic knee osteoarthritis status. We used a validated deep-learning method for thigh muscle MRI segmentation and calculation of muscle quality biomarkers at baseline, 2nd, and 4th visits. Mean difference and 95% confidence intervals (CI) in longitudinal 4-year measurements of muscle quality biomarkers, including cross-sectional area, intramuscular adipose tissue, contractile percent, and knee extensors and flexors maximum and specific contractile force (force/muscle area) were the outcomes of interest.

RESULTS

After matching, 3772 thighs of 1910 participants were included (1886 thighs of statin-users: 1886 of non-users; age: 62 ± 9 years (average ± standard deviation), range: 45-79; female/male: 1). During 4 years, statin use was associated with a slight decrease in muscle quality, indicated by decreased knee extension maximum (mean-difference, 95% CI: - 1.85 N/year, - 3.23 to - 0.47) and specific contractile force (- 0.04 N/cm2/year, - 0.07 to - 0.01), decreased thigh muscle contractile percent (- 0.03%/year, - 0.06 to - 0.01), and increased thigh intramuscular adipose tissue (3.06 mm2/year, 0.53 to 5.59). Stratified analyses showed decreased muscle quality only in participants without/at-risk of knee osteoarthritis but not those with established knee osteoarthritis.

CONCLUSIONS

Statin use is associated with a slight decrease in MRI-based measures of thigh muscle quality over 4 years. However, considering statins' substantial cardiovascular benefits, these slight muscle changes may be relatively less important in overall patient care.

Rare forms of inflammatory myopathies - part II, localized forms

INTRODUCTION

The idiopathic inflammatory myopathies traditionally comprise dermatomyositis, polymyositis, the anti-synthetase syndromes, immune-mediated necrotizing myopathy and inclusion body myositis. However, there are uncommon localized forms that are less known. In this review, we aimed to cover these uncommon forms.

AREAS COVERED

We identified rare forms of localized myositis on the basis of list provided by the homepage of the Neuromuscular disease center of Washington University, USA and on the basis of the authors' knowledge. We searched PubMed® for relevant articles on these forms with the aim of providing as much as possible information on their clinical manifestations as well as guidance on their work-up and treatment.

EXPERT OPINION

herein, we provide un updated description of rare forms of localized myositis. These forms are often difficult to diagnose because of their localized nature and are sometimes misdiagnosed as tumors. Knowledge about these rare forms of localized myositis can aid in their recognition and treatment.

Statin-related Muscle Toxicity: An Evidence-based Review

The efficacy of statins in the primary and secondary prevention of cardiovascular disease has been proven beyond doubt. The number needed to treat to prevent one cardiovascular event is 1 in 30 over 10 years, and the number needed to treat for secondary prevention is much lower. However, a recent study demonstrated that only 68% of eligible patients are on statin therapy. Moreover, there seems to be a reluctance to escalate statin doses due to the fear of adverse effects. The adverse effects that worries patients and their physicians most frequently are those related to muscular symptoms. N-of-1 trial evidence suggests that muscular symptoms attributed to statins are often caused by the nocebo effect. This article aims to provide a structured, evidence-based approach to suspected statin-related muscle toxicity.

A Patient With Focal Myositis and Primary Cutaneous Diffuse Large B-Cell Lymphoma: A Case Report

We report a rare case of a 92-year-old male, with a history of statin/ezetimibe intake, complained of pain and swelling of left forearm. The patient was diagnosed with focal myositis at first. Symptoms aggravated after 2 months of immunomodulatory therapy, and accompanied with protrusion lesion at left elbow. Biopsy of the protrusion lesion turned out to be primary cutaneous diffuse large B-cell lymphoma.

Focal myositis: New insights on diagnosis and pathology

OBJECTIVE

To better define in a cohort study the clinical and pathologic features of focal myositis (FM).

METHODS

With the use of the usual clinicopathologic definition, each confirmed case of FM in the Lyon University Hospital's myopathologic database between 2000 and 2016 was retrieved. Clinical, pathologic, imaging, serologic, and therapeutic data were collected. When data were missing but feasible, appropriate pathologic analyses were performed.

RESULTS

Of the 924 patients included in the database, 37 (4%) had confirmed FM (14 female, 23 male patients). The main symptoms were pain (n = 30, 81%), muscular mass (n = 16, 43%), erythema at the site of FM (n = 12, 32%), and fever (n = 9, 24%). Serum creatine kinase was normal in most patients (81%); serum immune abnormalities were frequent (inflammatory syndrome in sera [39%], dysglobulinemia [52%], and anti-nuclear antibody positivity [29%]). In addition to confirming previously reported findings, pathologic analyses found significant rates of vasculitis (68%) and fasciitis (73%). Here, FM appeared frequently to be associated with other diseases such as immune-mediated inflammatory disease (IMID; 32%), neoplasia (24%), and radiculopathy (11%). Regarding outcomes, 64% of the cases had received immunosuppressive drugs, and the relapse rate was 41%.

CONCLUSION

The present study suggests that FM is not as innocuous as previously believed, particularly considering the associated disorders. Notably, patients with FM should receive careful IMID and neoplasia screening.

Focal myositis: A review

Amongst the heterogeneous group of inflammatory myopathies, focal myositis stands as a rare and benign dysimmune disease. Although it can be associated with root and/or nerve lesions, traumatic muscle lesions and autoimmune diseases, its triggering factors remain poorly understood. Defined as an isolated inflammatory pseudotumour usually restricted to one skeletal muscle, clinical presentation of focal myositis is that of a rapidly growing solitary mass within a single muscle, usually in the lower limbs. Electromyography shows spontaneous activity associated with a myopathic pattern. MRI reveals a contrast enhanced enlarged muscle appearing hyper-intense on FAT-SAT T2 weighted images. Adjacent structures are spared and there are no calcifications. Serum creatine kinase (CK) levels are usually moderately augmented and biological markers of systemic inflammation are absent in most cases. Pathological histological features include marked variation in fibre size, inflammatory infiltrates mostly composed of T CD4+ lymphocytes and macrophages, degenerating/regenerating fibres and interstitial fibrosis. Differential diagnoses are numerous and include myositis of other origin with focal onset. Steroid treatment should be reserved for patients who present with major pain, nerve lesions, associated autoimmune disease, or elevated C reactive protein or CK.

Drug-induced rheumatic diseases: a review of published case reports from the last two years

PURPOSE OF REVIEW

New drugs are continuously being developed and some rheumatic syndromes have been associated with specific drugs. As most of the rheumatic diseases are multisystem, it is worthwhile examining the wider case report literature to see whether any recent studies signify new associations between drugs and the rheumatic diseases. The last 2 years' case reports in English were scrutinized for noninfectious association with the rheumatic diseases. Cross-referencing from MEDLINE was performed using several databases including Google scholar; British Medical Journal (BMJ) case reports were also queried separately.

RECENT FINDINGS

Fifty-three articles comprising 56 case reports are included in the review, with 27 (48.2%) associated with the vasculitides, eight (14.3%) associated with lupus and 13 (23.2%) were associated with the myositis syndromes. The commonest four groups of drugs to potentially induce rheumatic diseases were anti-tumour necrosis factor (TNF) drugs, oncology drugs, propylthiouracil and interferons.

SUMMARY

It is important to recognise that drugs used in other specialties may induce rheumatic disease and vigilance on making a diagnosis is the key.

Magnetic resonance imaging of inflammatory myopathies

The following article reviews the role of magnetic resonance imaging (MRI) in patients with idiopathic inflammatory myopathies (IIMs), focusing on the 3 major types of IIM: polymyositis, dermatomyositis, and inclusion-body myositis. After a brief introduction with general information about IIM, we will discuss the reasons why MRI plays an important role in the diagnosis and management of patients with polymyositis, dermatomyositis, and inclusion-body myositis. Magnetic resonance imaging can confirm the diagnosis and can help to phenotype the disease. Moreover, the support of MRI is important in addressing the muscle biopsy site and in reducing the high false-negative rate of biopsy when performed in a blind fashion. In monitoring therapy, MRI can add important information about the activity of the muscle disease and can identify cases where continued immunosuppressive therapy is no longer warranted owing to complete fatty replacement of the muscles. Lastly, we provide an overview about some advanced MRI techniques that focus more on function than on morphology of muscle.