Muscle biopsy with dystrophic pattern and rimmed vacuoles: GNE myopathy in a Brazilian patient

GNE myopathy (MIM#605820) is a rare autosomal recessive disorder with a higher prevalence in individuals with Middle Eastern or Japanese ancestries[1]. We present a 23-year-old Brazilian female, without such ancestries, with slowly progressive distal and proximal weakness in her lower limbs since the age of 18. Within five years, weakness progressed to her upper limbs and led to loss of ambulation (sparing the quadriceps somewhat). The muscle biopsy is shown in the [Figure]. Exome analysis revealed compound heterozygous variants on GNE gene (p.Arg193Cys, known[2], and p.Arg132Cys, novel). This is the first South American patient report, which illustrates the utility of high-throughput sequencing to diagnose rare and potentially treatable disorders[1],[3].

Figure Dystrophic pattern with rimmed vacuoles with autophagic aspect (arrows) on muscle biopsy. A) H&E (bar= 50 μm). B) Gomori's trichrome (bar= 50 μm). C) Acid phosphatase (bar= 50 μm). D) Electron microscopy (bar = 1000 nm).

Conflict of interest:

There is no conflict of interest to declare.

• References

• 1 Nishino I, Carrillo-Carrasco N, Argov Z. GNE myopathy: current update and future therapy. J Neurol Neurosurg Psychiatry. 2015;86(4):385-92. doi:10.1136/jnnp-2013-307051
• 2 Del Bo R, Baron P, Prelle A, Serafini M, Moggio M, Fonzo AD et al. Novel missense mutation and large deletion of GNE gene in autosomal-recessive inclusion-body myopathy. Muscle Nerve. 2003;28(1):113-7. doi:10.1002/mus.10391
• 3 Mori-Yoshimura M, Nishino I. [Sialic acid replacement therapy for distal myopathy with rimmed vacuoles]. Brain Nerve. 2015;67(9):1115-23. Japanese. doi:10.11477/mf.1416200269

Publication History

Received: 22 July 2016

Accepted: 01 September 2016

Article published online:
06 September 2023