Neuropediatrics 2006; 37 - MP77
DOI: 10.1055/s-2006-943674

FACIOSCAPULOHUMERAL MUSCULAR DYSTROPHY: ATYPICAL PRESENTATIONS AND DIAGNOSTIC CONSIDERATIONS

L Billinghurst 1, H Kolski 1
  • 1Division of Neurology, Stollery Children's Hospital, University of Alberta, Edmonton, AB, Canada

Objectives: Facioscapulohumeral muscular dystrophy (FSHD) is a slowly progressive myopathy usually presenting with weakness of the face and scapulae. Atypical presentations have been reported. FSHD is diagnosed by demonstrating a deletion in a 3.3 kb DNA repeat motif (D4Z4) at chromosome 4q35 in 95% of individuals. However, interpretation of molecular genetic testing can be problematic, making definitive diagnosis difficult. The purpose of this case series is to report suspected geno-phenotypic variations in two patients with features suggestive of FSHD. Methods: Case Series.

Results: A 13 year-old male presented with asymmetric scapular winging and hip girdle weakness, along with bilateral weakness of the face and deltoids. There was no ophthalmoparesis and reflexes were normal. He reported poor exercise tolerance and was fatigueable during the exam. The second patient, a 4 year-old female, presented with congenital right ophthalmoparesis, severe articulation disorder, expressive language, fine and groß motor delays. Macrocephaly, facial weakness, hypotonia and hyporeflexia were evident. She had a mildly elevated CK but an unremarkable EMG. Neither child had visual or hearing impairments nor did they report a family history of FSHD. Given the atypical clinical presentations, genetic testing for FSHD was performed. Southern blot analysis using the probe 13E-11 and double digestion with EcoRI and BInI yielded the same result in both patients: three chromosome 10-type D4Z4 repeats and one chromosome 4-type D4Z4 repeats, indicative of a sequence rearrangement. One chromosome 10-type D4Z4 repeat had a large deletion. Should this repeat be the one located on chromosome 4, clinical manifestations of FSHD would be anticipated.

Conclusion: In view of the recognized expanding geno-phenotypic spectrum of FSHD, we propose that 4q35 deletions associated with chromsome 4–10 translocations may be symptomatic. This warrants further study.