Footnotes

• Contributors BEW wrote the case report. AA-B advised on histology and provided histology pictures. JNG provided intellectual content and critically revised the manuscript.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Patient consent for publication Obtained.

• Provenance and peer review Not commissioned; externally peer reviewed.