TY - JOUR
T1 - Muscle MRI in immune-mediated necrotizing myopathy (IMNM): implications for clinical management and treatment strategies
AU - Fionda, Laura
AU - Lauletta, Antonio
AU - Leonardi, Luca
AU - Perez, Jorge Alonso
AU - Morino, Stefania
AU - Merlonghi, Gioia
AU - Alfieri, Girolamo
AU - Costanzo, Rocco
AU - Tufano, Laura
AU - Vanoli, Fiammetta
AU - Rossini, Elena
AU - Vigo, Eduard Gallardo
AU - Tartaglione, Tommaso
AU - Salvetti, Marco
AU - Antonini, Giovanni
AU - Diaz-Manera, Jordi
AU - Garibaldi, Matteo
PY - 2023
Y1 - 2023
N2 - Objectives: Immune-mediated necrotizing myopathy (IMNM) is the most severe idiopathic inflammatory myopathy (IIM) and early aggressive poly-immunotherapy is often required to reduce long-term disability. The aim of this study is to investigate muscle MRI in IMNM as outcome measure for disease activity, severity, progression, response to treatment, and to better characterize the pattern of muscle involvement. Methods: This is a retrospective, observational, cross-sectional, and longitudinal study including 22 IMNM patients, divided into three groups based on timing of first MRI and if performed before or under treatment. T1 score and percentage of STIR positive muscles (STIR%) were considered and analyzed also in relation to demographic, clinical and laboratory characteristics. Results: STIR% was higher in untreated patients and in those who performed MRI earlier (p = 0.001). Pelvic girdle and thighs were in general more affected than legs. T1 score was higher in patients with MRI performed later in disease course (p = 0.004) with a prevalent involvement of the lumbar paraspinal muscles, gluteus medius and minimus, adductor magnus and hamstrings. 22% of STIR positive muscles showed fat replacement progression at second MRI. Higher STIR% at baseline correlated with higher risk of fat replacement at follow-up (p = 0.003); higher T1 score correlated with clinical disability at follow-up, with late treatment start and delayed treatment with IVIG (p = 0.03). Interpretation: Muscle MRI is a sensitive biomarker for monitoring disease activity and therapy response, especially when performed early in disease course and before treatment start, and could represent a supportive outcome measure and early prognostic index in IMNM.
AB - Objectives: Immune-mediated necrotizing myopathy (IMNM) is the most severe idiopathic inflammatory myopathy (IIM) and early aggressive poly-immunotherapy is often required to reduce long-term disability. The aim of this study is to investigate muscle MRI in IMNM as outcome measure for disease activity, severity, progression, response to treatment, and to better characterize the pattern of muscle involvement. Methods: This is a retrospective, observational, cross-sectional, and longitudinal study including 22 IMNM patients, divided into three groups based on timing of first MRI and if performed before or under treatment. T1 score and percentage of STIR positive muscles (STIR%) were considered and analyzed also in relation to demographic, clinical and laboratory characteristics. Results: STIR% was higher in untreated patients and in those who performed MRI earlier (p = 0.001). Pelvic girdle and thighs were in general more affected than legs. T1 score was higher in patients with MRI performed later in disease course (p = 0.004) with a prevalent involvement of the lumbar paraspinal muscles, gluteus medius and minimus, adductor magnus and hamstrings. 22% of STIR positive muscles showed fat replacement progression at second MRI. Higher STIR% at baseline correlated with higher risk of fat replacement at follow-up (p = 0.003); higher T1 score correlated with clinical disability at follow-up, with late treatment start and delayed treatment with IVIG (p = 0.03). Interpretation: Muscle MRI is a sensitive biomarker for monitoring disease activity and therapy response, especially when performed early in disease course and before treatment start, and could represent a supportive outcome measure and early prognostic index in IMNM.
KW - Follow-up study
KW - Immune mediated necrotizing myopathy (IMNM)
KW - Whole body muscle MRI
KW - Inflammatory myopathies
KW - Immunomodulating therapy
KW - Follow-up study
KW - Immune mediated necrotizing myopathy (IMNM)
KW - Whole body muscle MRI
KW - Inflammatory myopathies
KW - Immunomodulating therapy
UR - http://hdl.handle.net/10807/302992
U2 - 10.1007/s00415-022-11447-7
DO - 10.1007/s00415-022-11447-7
M3 - Article
SN - 0340-5354
VL - 270
SP - 960
EP - 974
JO - Journal of Neurology
JF - Journal of Neurology
ER -