Histologic muscular history in steroid-treated and untreated patients with Duchenne dystrophy.
OBJECTIVE
Duchenne muscular dystrophy (DMD) is a lethal disease. The outcome measures used in numerous therapeutic trials include skeletal muscle biopsy. We studied the natural history of DMD from the standpoint of muscle histology with the aim of providing a reproducible tool for use in evaluating and comparing any histologic changes occurring in patients with DMD undergoing treatment and hence be able to determine how therapy modulates the histologic evolution of the disease.


METHODS
Three independent operators analyzed 56 muscle biopsies from 40 patients not treated with steroids, aged 1 to 10 years and 16 individuals treated with steroids, aged 7 to 10 years. We analyzed morphologic measures, normalized every measure for the average number of fibers observed for each year of age, and calculated intraclass correlation coefficients.


RESULTS
The average proportion of connective tissue in patients not treated with steroids was 16.98% from ages 1 to 6 years and 30% from ages 7 to 10 years (p < 0.0001). The average proportion in patients treated with steroids was 24.90%. Muscle fiber area mirrored that of connective tissue in both groups.


CONCLUSIONS
Having provided a reproducible tool for evaluation and comparison of histologic changes occurring in patients undergoing clinical trials, it was observed that at ages 6 to 7 years, fibrotic tissue rapidly peaks to 29.85%; this is a crucial moment when muscle tissue loses its self-regeneration ability, veering toward fibrotic degeneration. These data should be considered when deciding the most suitable time to begin therapy.
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Lorenzo
L
Peverelli
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Silvia
S
Testolin
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Luisa
L
Villa
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Adele
A
D'Amico
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Stefania
S
Petrini
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Chiara
C
Favero
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Francesca
F
Magri
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Lucia
L
Morandi
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Marina
M
Mora
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Tiziana
T
Mongini
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Enrico
E
Bertini
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Monica
M
Sciacco
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy.
Giacomo P
GP
Comi
From the Neuromuscular and Rare Diseases Unit (L.P., S.T., L.V., M.S., M. Moggio), Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan; Laboratory of Molecular Medicine for Muscular and Neurodegenerative Diseases (A.D.), Research Center, Confocal Microscopy Facility (S.P.), and Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders (E.B.), Bambino Gesù Children's Hospital, Rome; Center of Molecular and Genetic Epidemiology (C.F.), Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan; Dino Ferrari Center (F.M., G.P.C.), Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda, Ospedale Maggiore Policlinico, Milan; U.O. Neuromuscular Diseases and Neuroimmunology (L.M., M. Mora), Fondazione IRCCS Istituto Neurologico C. Besta, Milan; and Department of Neurosciences Rita Levi Montalcini (T.M.), University of Turin, Italy. maurizio.moggio@unimi.it.
Maurizio
M
Moggio
D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D006801:Humans; D007223:Infant; D008297:Male; D053580:Muscle Strength / Q000187:drug effects / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000473:pathology*; D020388:Muscular Dystrophy, Duchenne / Q000175:diagnosis* / Q000188:drug therapy*; D012189:Retrospective Studies; D013256:Steroids / Q000494:pharmacology / Q000627:therapeutic use*; D016896:Treatment Outcome
D013256:Steroids