The authors report 2 cases of sea urchin granuloma of the nail apparat
us resulting in permanent nail deformity. Both patients developed peri
ungual and subungual nodular lesions 1-2 months after sea urchin spine
injuries in the Mediterranean sea. The affected nails showed periungu
al nodules associated with splitting of the nail plate distal to the n
odules. Surgical excision of the nail lesions required the removal of
a large amount of nail matrix that resulted in permanent nail plate dy
strophy. Histopathology revealed typical foreign-body granulomas in th
e nail dermis.