Pterygium inversum unguis is
defined as an acquired condition in which the distal part of the nail-bed
remains adherent to the ventral surface of the nail-plate thus obliterating
the distal groove. It has been reported as a typical finding
of systemic sclerosis, resulting from soft tissue atrophy.
We have seen some cases in SLE patients with vasculitic involvement of the hands.
Pterygium inversum unguis in a SLE patient.
A 29 year old woman with an 8 year history of SLE. Six years prior to our observation she had suffered from vasculitic hand involvement with necrotic/suppurative lesions affecting the periungual soft tissues: repeated episodes involved all fingers and toes during a six-month period and caused the progressive formation of tight adherence between the distal part of the nail-bed and the nail-plate.
We have no records to precisely define the nature of the phenomenon (i.e. vasculitic lesions or simply bacterial or mycotic infection during immunosuppressive treatment).
Nonetheless, this case shows that pterygium inversum unguis may be a secondary phenomenon and may be encountered also in SLE patients.