Focal and other unusual presentations of facioscapulohumeral muscular dystrophy

Department of Neurology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, Minnesota 55905, USA.
Muscle & Nerve (Impact Factor: 2.28). 09/2012; 46(3):421-5. DOI: 10.1002/mus.23358
Source: PubMed


Facioscapulohumeral dystrophy (FSHD) presents classically with facial and shoulder-girdle weakness. We report focal atypical presentations of FSHD. Our aim was to identify focal/unusual phenotypes in genetically confirmed FSHD cases.
We undertook a retrospective review of an academic center database of the period from 1996 to 2011. Of 139 FSHD cases, 7 had atypical genetically confirmed disease. Clinical data were abstracted.
Seven cases (4 men) had a mean age of 37 years at onset (range 18-63 years) and mean 43 years at diagnosis (range 20-74 years). Presenting symptoms were monomelic lower limb (n = 3) or upper limb (n = 2) atrophy, or axial weakness (n = 2). Five patients had focal weakness on examination. CK was normal to borderline high. Two patients had a relative with FSHD. Coexistent unusual features included dyspnea (n = 1), S1 radicular pain with calf atrophy (n = 2), and peripheral neuropathy (n = 1). Almost all patients had myopathic EMG changes. DNA analysis showed a D4Z4 EcoRI fragment size ranging from 20 to 37 kilobases.
FSHD may present with focal weakness, dyspnea and myopathic EMG changes. These findings should raise the possibility of FSHD.

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Available from: Anhar Hassan, Jul 24, 2014
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