title: Variable histological expression of dystrophinopathy in two females.
abstract: We report two carriers of Xp21 muscular dystrophy with unusual clinical manifestations and striking variability of dystrophin deficiency within the same muscle biopsy. The first patient was a 60-year-old nun with recent onset of cramps and proximal weakness, mimicking an acquired myopathy. Muscle biopsy disclosed slight alterations in one sample and severe dystrophic changes in another; dystrophin was absent in 7% fibers in the former specimen and in 60% in the second. X inactivation was skewed with 90% cells inactivating the same X chromosome. The second patient was a 17-year-old girl with hyperCKemia, learning disability and a family history of X-linked muscular dystrophy. Muscle biopsy displayed slight fiber size variability and some internal nuclei; dystrophin was absent only in one muscle fiber. A second sample with the same morphological features demonstrated dystrophin deficiency with mosaic distribution. The pattern of X inactivation was normal. These cases emphasize the variability of histopathological changes and dystrophin deficiency in Xp21 muscular dystrophy carriers and the risk of sampling errors in muscle biopsy.
authors.affiliation: Centro per le Malattie Neuromuscolari Paolo Peirolo, Torino, Italy. palmucci@medfarm.unito.it
authors.forename: C
authors.initials: C
authors.lastname: Doriguzzi
authors.forename: L
authors.initials: L
authors.lastname: Palmucci
authors.forename: T
authors.initials: T
authors.lastname: Mongini
authors.forename: L
authors.initials: L
authors.lastname: Chiadò-Piat
authors.forename: C
authors.initials: C
authors.lastname: Saggiorato
authors.forename: I
authors.initials: I
authors.lastname: Ugo
authors.forename: E P
authors.initials: EP
authors.lastname: Hoffman
mesh_terms: D000293:Adolescent; D005260:Female; D006801:Humans; D008875:Middle Aged; D009132:Muscles / Q000473:pathology; D009136:Muscular Dystrophies / Q000235:genetics / Q000473:pathology*; D014960:X Chromosome / Q000235:genetics