Comparison of therapeutic efficacy between lateral type of distal and lateral subungual onychomycosis (DLSO) and non-lateral types of DLSO

Background: Onychomycosis is a common fungal infection accounting for 50% of all nail disorders. Above all the clinical types of onychomycosis, distal and lateral subungual onychomycosis (DLSO) is the most common clinical type seen up to 70-90% in onychomycosis patients. Even though the cure rate and recurrence rate of DLSO are considered to be different according to the clinical type of DLSO. Clinical experience, there is a few clinical study showing the difference. Objectives: This is to investigate the therapeutic efficacy of lateral type of DLSO comparing with the other types of DLSO. Methods: We reviewed 81 DLSO cases who visited our clinic from June 1^st, 2006 to June 31^st, 2010, and classified them into 2 groups; lateral type and non-lateral types including edge, distal and linear type. We treated the patients with oral antifungal agent for 4 months, and followed them up in 2 months. Scoring clinical index for onychomycosis (SCIO) was checked and photography was taken before treatment and after treatment. Results: There are no significant differences in average age and male to female ratio between lateral DLSO and non-lateral DLSO. The comparison of SCIO score distribution before treatment between lateral DLSO and non-lateral DLSO showed no significant statistical difference. However, there was significant change in SCIO score distribution after the treatment. Decreased SCIO score in lateral DLSO was 6.99, while non-lateral DLSO was 11.1 (p=0.018). There was 2cases worsen cases in lateral DLSO, while there was no worsen case in non-lateral DLSO (p=0.019). Conclusion: Lateral DLSO is more difficult to treat than non-lateral DLSO.