Spiradenoma causing longitudinal splitting of the nail.

Longitudinal splitting of the nails can occur as a result of any growth arising in the nail matrix. We present a case of a 50-year-old woman who presented with an 18-month history of longitudinal splitting of the nail on her right little finger, along with pain in the proximal nail fold region, which was extremely tender to touch. Magnetic resonance imaging revealed an intensely enhancing lesion, while colour Doppler imaging revealed hypervascularity within the mass. A provisional diagnosis of glomus tumour was considered. Histopathology demonstrated presence of a well-circumscribed tumour comprising a dual population of cells, which stained negatively with periodic-acid-Schiff. The histopathological features were consistent with those of eccrine spiradenoma (ES). In this case, glomus tumour was considered as the first differential diagnosis, but histopathology confirmed it as an ES.