PMC3975748_01
Moderate degree of fiber size variation with increased endomysial and perimysial connective tissue. Intrafascicular and perivascular lymphoid aggregates are noted (a; HE). Higher magnification reveals hypertrophic vacuolated fibers. Scattered atrophic and necrotic fibers with intrafascicular lymphocytic infiltration are present (b; HE). Rimmed vacuoles are highlighted by mGT stain (c; mGT). Tubulofilamentous inclusion, myeloid bodies, and autophagic vacuoles in the area corresponding to rimmed vacuoles (d; bar = 1 mum).
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PMC3975748_01_crn-0006-0055-g01.jpg
F1
There was perivascular and scattered intrafascicular lymphocytic infiltration (fig. 1a) with scattered necrotic and regenerating fibers. Vacuolated fibers were predominantly hypertrophic (fig. 1b). Rimmed vacuoles were highlighted by modified Gomori trichrome (mGT) stain (fig. 1c). Ultrastructural study showed tubulofilamentous inclusions, myeloid bodies, and autophagic vacuoles in the areas corresponding to rimmed vacuoles (fig. 1d).
Electropherogram of compound heterozygous mutations in this patient. A novel mutation c.1057A>G in exon 6 resulting in substitution of lysine to glutamic acid (p.K353E) is presented (a). A known mutation c.2086G>A in exon 12 resulting in substitution of valine to methionine (p.V696M) is presented (b).
crn-0006-0055-g02.jpg
PMC3975748_01_crn-0006-0055-g02.jpg
F2
A heterozygous substitution of adenine (A) to guanine (G) at nucleotide position 1057 (c.1057A>G) in exon 6 was identified, resulting in a lysine to glutamic acid substitution at codon 353 (p.K353E) in the epimerase domain (fig. 2a). A heterozygous substitution of G to A at nucleotide position 2086 (c.2086G>A) in exon 12 was present, resulting in a valine to methionine substitution at codon 696 (p.V696M) in the kinase domain (fig. 2b). c.1057A>G (p.K353E) was not present in the screening of 376 normal chromosomes from 188 Thai subjects.