Dermatomyosite induite par la fluvastatine

Causes and Clinical Presentation of Drug-Induced Dermatomyositis: A Systematic Review

Importance

While several medications are known to induce dermatomyositis (DM), most existing studies are case reports or small case series from a single institution. There is also limited information on DM induced by immune checkpoint inhibitors, which are increasingly used in oncologic therapy.

Objective

To characterize causes and clinical presentation of drug-induced DM based on the current literature.

Evidence Review

A systematic review was performed in PubMed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines, from inception to August 22, 2022. Articles meeting preestablished inclusion criteria (written in English and classified as original articles, case reports, literature reviews, and observation letters) were selected and data abstracted. Articles that met the scope of the review were also added from reference lists. When possible, study results were quantitatively combined.

Findings

In 134 studies (114 from the literature search and 20 additional studies pulled from reference lists) describing 165 cases, 88 patients (53.3%) were female, and the median (IQR) age was 61 (49-69) years. Among the cases of drug-induced DM, the most common associated medications were hydroxyurea (50 [30.3%]), immune checkpoint inhibitors (27 [16.4%]), statins (22 [13.3%]), penicillamine (10 [6.1%]), and tumor necrosis factor inhibitors (10 [6.1%]). Histopathologic testing, when undertaken, helped establish the diagnosis. There was a median (IQR) of 60 (21-288) days between drug initiation and drug-induced DM onset. History of cancer was reported in 85 cases (51.6%).

Conclusions and Relevance

In this systematic review, drug-induced DM was associated with multiple types of medications, including chemotherapies and immunotherapies. It is essential that dermatologists promptly recognize and diagnose drug-induced DM so that they can guide management to minimize interruption of therapy when possible.

Environmental exposures as risk factors for idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of rare autoimmune diseases, with increasing incidence rates observed in the recent years. The pathogenesis of IIM remains not fully understood, and the interaction of genetic and environmental factors is suspected. It is unclear whether the observed upward trend in the IIM incidence is solely due to improved access to effective diagnostics or perhaps due to increased exposure to external risk factors. The PUBMED database was thoroughly searched for articles describing environmental exposures potentially triggering the onset of IIM. The article summarizes the current knowledge available on this subject, taking into account various environmental factors, including among others UV radiation, infectious agents with SARS-CoV-2, inhaled particles, or iatrogenic effects. Limitations and unmet needs requiring further studies were highlighted.

Statin use in patients with non-HMGCR idiopathic inflammatory myopathies: A retrospective study

Background

Statins are the most widely used lipid lowering therapies which reduce cardiovascular risk, but are associated with muscular adverse events (AEs). Idiopathic inflammatory myopathies (IIM) are autoimmune diseases of the muscle with higher risk of cardiovascular disease. More data is needed regarding statin safety in patients with intrinsic muscle disease such as IIM.

Hypothesis

Statins are tolerated in patients with IIM without leading to significant increase in muscular AEs.

Methods

Statin use was retrospectively examined in a longitudinal IIM cohort. Safety analysis included assessment of muscular and nonmuscular AEs by chart review. IIM patients receiving a statin during the cohort follow‐up period were matched to IIM patients not receiving a statin for comparative analysis of longitudinal outcomes.

Results

33/214 patients had a history of statin use. 63% started for primary prevention, while others were started for clinical ASCVD events, vascular surgery, IIM related heart failure, and cardiac transplantation. A high intensity statin was used in nine patients with non‐HMGCR myositis, and tolerated in 8/9 patients. Statin related muscular AE was noted in three patients. There were no cases of rhabdomyolysis, or statin related nonmuscular AEs in a median observation period of 5 years. In patients newly started on statins during cohort follow‐up (n = 7) there was no change in disease activity after statin initiation. Long term outcomes were not different between statin and nonstatin IIM control groups.

Conclusion

Statins were well tolerated in patients with non‐HMGCR positive IIM. Given the accelerated atherosclerotic risk in IIM patients, further prospective studies of statin safety in IIM patients are warranted.

Diplomats' Mystery Illness and Pulsed Radiofrequency/Microwave Radiation

Importance: A mystery illness striking U.S. and Canadian diplomats to Cuba (and now China) "has confounded the FBI, the State Department and US intelligence agencies" (Lederman, Weissenstein, & Lee, 2017). Sonic explanations for the so-called health attacks have long dominated media reports, propelled by peculiar sounds heard and auditory symptoms experienced. Sonic mediation was justly rejected by experts. We assessed whether pulsed radiofrequency/microwave radiation (RF/MW) exposure can accommodate reported facts in diplomats, including unusual ones. Observations: (1) Noises: Many diplomats heard chirping, ringing or grinding noises at night during episodes reportedly triggering health problems. Some reported that noises were localized with laser-like precision or said the sounds seemed to follow them (within the territory in which they were perceived). Pulsed RF/MW engenders just these apparent "sounds" via the Frey effect. Perceived "sounds" differ by head dimensions and pulse characteristics and can be perceived as located behind in or above the head. Ability to hear the "sounds" depends on high-frequency hearing and low ambient noise. (2) Signs/symptoms: Hearing loss and tinnitus are prominent in affected diplomats and in RF/MW-affected individuals. Each of the protean symptoms that diplomats report also affect persons reporting symptoms from RF/MW: sleep problems, headaches, and cognitive problems dominate in both groups. Sensations of pressure or vibration figure in each. Both encompass vision, balance, and speech problems and nosebleeds. Brain injury and brain swelling are reported in both. (3) Mechanisms: Oxidative stress provides a documented mechanism of RF/MW injury compatible with reported signs and symptoms; sequelae of endothelial dysfunction (yielding blood flow compromise), membrane damage, blood-brain barrier disruption, mitochondrial injury, apoptosis, and autoimmune triggering afford downstream mechanisms, of varying persistence, that merit investigation. (4) Of note, microwaving of the U.S. embassy in Moscow is historically documented. Conclusions and relevance: Reported facts appear consistent with pulsed RF/MW as the source of injury in affected diplomats. Nondiplomats citing symptoms from RF/MW, often with an inciting pulsed-RF/MW exposure, report compatible health conditions. Under the RF/MW hypothesis, lessons learned for diplomats and for RF/MW-affected civilians may each aid the other.

Inflammatory myopathy associated with statins: report of three cases

Statins are well-established lipid-lowering drugs that reduce morbidity and mortality due to cardiovascular disease and cause adverse effects relatively rarely. It is still unclear whether statins are capable of inducing an immune-mediated response directed against skeletal muscle. Here, we present the cases of three patients who developed inflammatory myopathy in the course of statin treatment. Moreover, multiple mitochondrial DNA deletions were found in two of them. The ability of statins to induce an immune-mediated response and their interactions with mitochondrial metabolism pathways are discussed.

Diagnosis and classification of drug-induced autoimmunity (DIA)

Since sulfadiazine associated lupus-like symptoms were first described in 1945, certain drugs have been reported to interfere with the immune system and induce a series of autoimmune diseases (named drug-induced autoimmunity, DIA), exemplified by systemic lupus erythematosus (SLE). Among the drugs, procainamide and hydralazine are considered to be associated with the highest risk for developing lupus, while quinidine has a moderate risk, and all other drugs have low or very low risk. More recently, drug-induced lupus has been associated with the use of newer biological modulators, such as tumor necrosis factor (TNF)-alpha inhibitors and cytokines. In addition to lupus, other major autoimmune diseases, including vasculitis and arthritis, have also been associated with drugs. Because resolution of symptoms generally occurs after cessation of the offending drugs, early diagnosis is crucial for treatment strategy and improvement of prognosis. Unfortunately, it is difficult to establish standardized criteria for DIA diagnosis. Diagnosis of DIA requires identification of a temporal relationship between drug administration and the onset of symptoms, but the relative risk with respect to dose and duration for each drug has rarely been determined. DIA is affected by multiple genetic and environmental factors, leading to difficulties in establishing a list of global clinical features that are characteristic of most or all DIA patients. Moreover, the distinction between authentic DIA and unmasking of a latent autoimmune disease also poses challenges. In this review, we summarize the highly variable clinical features and laboratory findings of DIA, with an emphasis on the diagnostic criteria.

Statins as a possible cause of inflammatory and necrotizing myopathies

BACKGROUND

Hydroxy-methyl-glutaryl Co-A reductase (HMGCR) inhibitors or statins are a well recognized cause of a variety of skeletal myopathic effects which generally resolve on stopping the medication. Recent reports, however, suggest that statins are associated with a unique autoimmune myopathy wherein symptoms persist or even progress after statin discontinuation and require immunosuppressive therapy. We performed a systematic review to examine the association of statins with inflammatory (dermatomyositis/polymyositis) and necrotizing myopathies.

METHODS

We searched PubMed, Ovid and Scopus for English language articles addressing statin associated inflammatory and necrotizing myopathies. Given the paucity of cases, we extended the search to include articles in all languages.

RESULTS

The search yielded 14 articles reporting a possible association of statins with inflammatory myopathies describing 10 cases of polymyositis and 14 cases of dermatomyositis, and 4 articles reporting a possible association of statins with necrotizing myopathies describing 63 cases. One study identified a unique antibody directed against HMGCR in patients with necrotizing myopathy. Systemic immunosuppressive therapy was required in majority of these cases for resolution of symptoms.

CONCLUSION

Statins have recently been associated with a variety of inflammatory myopathies including polymyositis, dermatomyositis, and a necrotizing myopathy. The association of statins with necrotizing myopathy is strengthened by the discovery that the serum of some of these patients contains an anti-HMGCR antibody. This suggests that statins can cause or unmask an immune mediated myopathy.

Terbinafine-induced dermatomyositis: a case report and literature review of drug-induced dermatomyositis

Dermatomyositis, a connective tissue disease syndrome where antibodies to the endothelium of the microvasculature of the skin, muscle and lung are implicated in lesional propagation, is characterized by photodistributed erythema, heliotrope rash, Gottron's papules, muscle weakness and interstitial pulmonary fibrosis. Endotheliotropic viruses and underlying neoplasia are among the inciting triggers. Uncommon drugs, namely the lipid-lowering agents, have been implicated in dermatomyositis. The patient, a 57-year-old man, developed a photodistributed rash and muscle weakness following treatment with the antifungal medication, terbinafine. A skin biopsy was performed, showing an atrophying interface dermatitis with pandermal mucinosis and striking vasculopathic changes including endothelial cell necrosis with denudement and basement membrane zone reduplication. Ultrastructural studies confirmed the presence of endothelial cell injury. Direct immunofluorescent testing showed prominent staining of C5b-9 along the dermal-epidermal junction and within the vasculature. Western blot studies showed strong seroreactivity of his serum to an endothelial-based protein weighing 45,000, a common target described in other microvascular injury-based syndromes. We have shown a temporal association between use of terbinafine and the development of dermatomyositis. The exact basis remains speculative. One potential hypothesis is based on the fact that terbinafine, the active agent in terbinafine, triggers apoptosis of human endothelial cells in culture. Enhanced endothelial cell apoptosis results in the displacement of various cellular antigens creating a state of neoantigenicity; its attendant sequelae is held to be one of anti-endothelial cell antibody formation, a defining pathogenetic event in the evolution of dermatomyositis. The second may be because of the effects of the drug on the promotion of an interferon-rich T-helper-1-dominant cytokine milieu.