Océane Landon-Cardinal1, Cédi Koumako2, Giulia Hardouin3, Benjamin Granger3, Harmen Reyngoudt2, Jean-Marc Boisserie2, Aude Rigolet4, Baptiste Hervier4, Nicolas Champtiaux4, Perrine Guillaume-Jugnot4, Mathieu Vautier4, Olivier Benveniste4, Pierre G Carlier2, Yves Allenbach4. 1. Department of Internal Medicine and Clinical Immunology and Inflammation-Immunopathology-Biotherapy Department (I2B), Pitié-Salpêtrière University Hospital, Assistance Publique-Hôpitaux de Paris, East Paris Neuromuscular Diseases Reference Center, Inserm U974, Sorbonne Université, Paris 6, Paris, France; Department of Medicine, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada; Division of Rheumatology and Research Center, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada. Electronic address: oceane.landon-cardinal@umontreal.ca. 2. Laboratoire de RMN AIM & CEA, Centre d'Explorations Neuro-musculaires, Institut de Myologie, Paris, France. 3. Département de Biostatistiques, Santé Publique et Information Médicale, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France. 4. Department of Internal Medicine and Clinical Immunology and Inflammation-Immunopathology-Biotherapy Department (I2B), Pitié-Salpêtrière University Hospital, Assistance Publique-Hôpitaux de Paris, East Paris Neuromuscular Diseases Reference Center, Inserm U974, Sorbonne Université, Paris 6, Paris, France.
Abstract
BACKGROUND: Our objective was to define the pattern and severity of muscle damage in immune-mediated necrotizing myopathy (IMNM) and its relationship with clinical and serological features. METHODS: IMNM patients with a whole-body MRI (n=42) were included and compared to sporadic inclusion-body myositis (s-IBM) patients (n=60). Fat replacement was estimated using the Mercuri score in 55 muscles. Overall lesion load was defined as the sum of all abnormal Mercuri scores (reported in % maximal score) and lesion load quotient was defined as the overall lesion load divided by disease duration. Linear relationships between variables were assessed and multidimensional analysis was performed to define homogenous groups of patients. RESULTS: IMNM patients were aged 48.1±15.8 years and had a disease duration of 9.8±8.1 years. Most severely affected muscle groups were located in the pelvifemoral and lumbar region. Unsupervised analysis showed two subgroups of patients: one with mild lesion load (15±10%, n=32/42) and another with severe lesion load (60±10%, n=10/42: p<0.001) associated with a mean disease duration of 6.8±6.0 years and 19.5±5.7 years, respectively (p<0.0001). Correlational studies confirmed that disease duration was the most important predictor of muscle damage. Multivariate analyses demonstrated a more severe involvement in select muscle groups in females and seropositive patients. No difference was found in overall lesion load quotient of IMNM compared to IBM (p=0.07) but with a distinct muscle pattern. CONCLUSION: IMNM is associated with severe axial and pelvifemoral muscle damage. Disease duration is an important predictor of muscle damage. IMNM and s-IBM patients have a comparable damage burden. Crown
BACKGROUND: Our objective was to define the pattern and severity of muscle damage in immune-mediated necrotizing myopathy (IMNM) and its relationship with clinical and serological features. METHODS: IMNM patients with a whole-body MRI (n=42) were included and compared to sporadic inclusion-body myositis (s-IBM) patients (n=60). Fat replacement was estimated using the Mercuri score in 55 muscles. Overall lesion load was defined as the sum of all abnormal Mercuri scores (reported in % maximal score) and lesion load quotient was defined as the overall lesion load divided by disease duration. Linear relationships between variables were assessed and multidimensional analysis was performed to define homogenous groups of patients. RESULTS: IMNM patients were aged 48.1±15.8 years and had a disease duration of 9.8±8.1 years. Most severely affected muscle groups were located in the pelvifemoral and lumbar region. Unsupervised analysis showed two subgroups of patients: one with mild lesion load (15±10%, n=32/42) and another with severe lesion load (60±10%, n=10/42: p<0.001) associated with a mean disease duration of 6.8±6.0 years and 19.5±5.7 years, respectively (p<0.0001). Correlational studies confirmed that disease duration was the most important predictor of muscle damage. Multivariate analyses demonstrated a more severe involvement in select muscle groups in females and seropositive patients. No difference was found in overall lesion load quotient of IMNM compared to IBM (p=0.07) but with a distinct muscle pattern. CONCLUSION: IMNM is associated with severe axial and pelvifemoral muscle damage. Disease duration is an important predictor of muscle damage. IMNM and s-IBM patients have a comparable damage burden. Crown
Authors: Jeremy X Wang; Michael Wilkinson; Christopher Oldmeadow; Vidya Limaye; Gabor Major Journal: Rheumatology (Oxford) Date: 2022-08-30 Impact factor: 7.046
Authors: Robert L Kruse; Jemima Albayda; Sonja O Vozniak; Courtney E Lawrence; Ruchika Goel; Parvez M Lokhandwala; Paul M Ness; Aaron A R Tobian; Evan M Bloch; Elizabeth P Crowe Journal: J Clin Apher Date: 2022-02-04 Impact factor: 2.605