Abnormal white matter tracts resembling pencil fibers involving prefrontal cortex (Brodmann area 47) in autism: a case report

J Med Case Rep. 2016 Aug 26;10(1):237. doi: 10.1186/s13256-016-1020-6.


Background: Autism is not correlated with any neuropathological hallmark as the brain of autistic individuals lack defined lesions. However, previous investigations have reported cortical heterotopias and local distortion of the cytoarchitecture of the neocortex in some cases of autism.

Case presentation: Our patient was a 40-year-old white woman diagnosed at an early age with autism and mental retardation. Pencil fibers were present within the prefrontal cortex (Brodmann area 47) and its composition resembled that of the underlying white matter region. Pencil fibers encompassed most of the extent of the cortical grey matter and were populated by oligodendrocytes, astrocytes, and microglial cells, but not by neurons.

Conclusions: Here we report a new cytoarchitectural abnormality that has not been previously described in autism. Future pathological examinations should keep in mind the potential presence of pencil fibers within the prefrontal cortex of cases with autism.

Keywords: Autism; Case report; Cerebral cortex; Human; Pathology; Pencil fibers; Prefrontal.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Autistic Disorder / diagnostic imaging*
  • Autistic Disorder / pathology*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Prefrontal Cortex / diagnostic imaging*
  • Prefrontal Cortex / pathology*
  • White Matter / diagnostic imaging*
  • White Matter / pathology*