Naslov
Oculopharyngeal muscular dystrophy-case report

Autori
Bauer-Šegvić, A ; Milić, Astrid ; Ljubanović, Danica ; Canki-Klain, Nina

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
15th Ljudevit Jurak international symposium on comparative pathology / - Zagreb, 2004

Skup
15th Ljudevit Jurak international symposium on comparative pathology

Mjesto i datum
Zagreb, Hrvatska, 04.06.2004. - 05.06.2004

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
oculopharyngeal muscular dystrophy; OPMD; intranuclear inclusions; PABP2 gene

Sažetak
Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset autosomal dominant disease with a worldwide distribution. It usually presents in the sixth decade with progressive dysphagia, ptosis and proximal limb weakness. Unique nuclear filament inclusions in skeletal muscle fibres are its pathologic hallmark. It is caused by stable (GCG)8-13 expansions in exon 1 of poly(A)-binding protein 2 gene (PABP2). (GCG)6 represents normal repeat length while (GCG)7 is a polymorphism that acts as a modifier of the disease severity or as a recessive mutation. More severe phenotypes were observed in compound heterozygotes for the (GCG)9 mutation and (GCG)7 allele that is found in 2% of the population. We report on the histological study in a 56-year old woman who had progressive eyelid dropping from the age of 48. She had mild dysphagia, hardly noticed opthalmoplegia and severe proximal limb girdle weakness that had started around the age of 56 when she had been hospitalized and found to have a myogenic pattern of EMG, high serum level of creatine kinase and stenocardia. Muscle biopsy was performed. The biopsy specimen was examined by light and electron microscopy. Tissue samples for light microscopy were fixed in formalin, embedded in paraffin and stained with hematoxylin and eosin. Electron microscopy samples were prepared according to standard procedure. Light microscopy showed normal arrangement and different thickness of muscle fibers. Examination of semi-thin sections showed the presence of a clear zone in some muscle fiber nuclei (intranuclear inclusions). On electron microscopy these inclusions were made of tubular filaments arranged in tangles or palisades. The filaments were seen in muscle fibers but not in the cytoplasm or other cells found in the samples. The muscle fibers had otherwise normal ultrastructure. The intranuclear inclusions are specific for oculopharyngeal muscular dystrophy. Several years later, DNA analysis confirmed the diagnosis of OPMD, finding her to be a compound heterozygote for (GCG)8 mutation and (GCG)7 allele of PABP2 gene. Until the identification of PABP2 gene mutations, definitive diagnosis relied on electron microscopy observation of intranuclear inclusions. Noninvasive DNA testing from peripheral blood has now replaced this approach. The test is reliable, can be done in Zagreb and permits accurate genetic counselling

Izvorni jezik
Engleski

Znanstvena područja
Javno zdravstvo i zdravstvena zaštita

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