Footnotes

• Contributors SKT wrote the manuscript with supervision by NT. CB and MS collated patient history, conducted examination and organised investigations with supervision by TL, and further follow-up by SKT.

• 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.

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