Predominant fiber atrophy and fiber type disproportion in early ullrich disease.
Ullrich disease (congenital muscular dystrophy type Ullrich, UCMD) is a severe congenital disorder of muscle caused by recessive and dominant mutations in the three genes that encode the alpha-chains of collagen type VI. Little is known about the early pathogenesis of this myopathy. The aim of this study was to investigate early histological changes in muscle of patients with molecularly confirmed UCMD. Muscle biopsies were analyzed from 8 UCMD patients ranging in age from 6 to 30 months. Type I fiber atrophy and predominance were seen early, together with a widening of the fiber diameter spectrum, whereas no dystrophic features were apparent. A subpopulation of more severely atrophic type I fibers was apparent subsequently, including one biopsy that fulfilled the formal diagnostic criteria of histopathological fiber type disproportion (FTD). Thus, early in the disease, UCMD presents as a non-dystrophic myopathy with predominant fiber atrophy. Collagen VI mutations also qualify as a cause of fiber type disproportion.
Schessl
Joachim
J
Division of Neurology, The Children's Hospital of Philadelphia, Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Abramson Research Center, 516F, 34th Street and Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA.
Goemans
Nathalie M
NM
Magold
Alexandra I
AI
Zou
Yaqun
Y
Hu
Ying
Y
Kirschner
Janbernd
J
Sciot
Raf
R
Bönnemann
Carsten G
CG
D000251:Adenosine Triphosphatases / Q000378:metabolism; D001706:Biopsy / Q000379:methods; D002675:Child, Preschool; D024142:Collagen Type VI / Q000378:metabolism; D005260:Female; D006801:Humans; D007211:Indoles; D007223:Infant; D007797:Laminin / Q000378:metabolism; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000378:metabolism / Q000473:pathology*; D009133:Muscular Atrophy / Q000209:etiology* / Q000473:pathology*; D018995:Myosin Heavy Chains / Q000378:metabolism; D009223:Myotonic Dystrophy / Q000150:complications* / Q000473:pathology
D024142:Collagen Type VI; D007211:Indoles; D007797:Laminin; C089141:laminin gamma 1; C007293:DAPI; D000251:Adenosine Triphosphatases; D018995:Myosin Heavy Chains