Therapeutic effect of intra-lesional triamcinolone injection on idiopathic onychodystrophy

Background: Intra-lesional triamcinolone injection is a widely used treatment modality of onychodystrophy. However, clinical evaluation has rarely been performed for the therapeutic effect of intra-lesional triamcinolone injection in the treatment of idiopathic onychodystrophy, except for psoriatic nail. Objective: The purpose of this study was to investigate the therapeutic effect of intra-lesional triamcinolone injection on idiopathic onychodystrophy. Methods: A total of 43 patients diagnosed as idiopathic onychodystrophy were enrolled in this study. At first 2 visits, triamcinolone acetonide (2.5mg/ml) was injected into the proximal nail fold of each nail using the dermo-jet. Thereafter, intra-lesional injection was performed at 4-week intervals with two-fold increased concentration of triamcinolone acetonide (5mg/ml). After a total of 7 treatments, the treated nails were scored by both doctor and patient between O and 10 according to the severity. Results: In 26 patients treated for more than 12-weeks, 189 nails were eventually assessed by four grade scale. Therapeutic effects were as follows; excellent improvement in 19.8%, good in 28.8%, moderate in 11.6%, and poor in 38.6%. Onycholysis responded well to this treatment, with 81.1% of good to excellent improvement, whereas trachyonychia was resistent with 78.1% of poor to moderate improvement. There was no significant side effect, except pain on the injection site. Conclusion: According to our results, intra-lesional injection of triamcinolone acetonide is an effective and safe treatment modality of idiopathic onychodystrophy. It is suggested that, with intra-lesional triamcinolone injection, the morphologic classification is an important prognostic factor in the treatment of idiopathic onychodystrophy.