Clinical Study of Onychomycosis: Factors Contributing to the Prognosis and Reponse Rate According to Each Factor and Summation of Factors

Kim, Duk Han; Park, Hyun Jeong; Lee, Jun Young; Cho, Baik Kee

Abstract

BACKGROUND
The treatment of onychomycosis has improved recently. However, for 25% of patients, persistent disease remains a problem. Predisposing factors that contribute to a poor treatment response include a thick nail, extensive nail involvement, lateral nail involvement, dermatophytoma, onycholysis and yellow spikes. OBJECTIVES: Our purpose was to study the clinical characteristics of onychomycosis contributing to the prognosis. METHODS: On the basis of the charts, photographs and telephone-visiting of the patients who visited St. Mary's hospital from January 2000 to May 2004, we investigated the number and percentage of good-responders according to each prognostic factor and the number of factors. RESULTS: 1. KOH smear, fungus culture and KONCPA test showed positivity rates of 61.0% (347/569), 17.4% (101/581) and 75.1% (284/378), respectively. 2. Triple tests showed positivity rate of 86.9% (271/312) by one or more of the triple tests. 3. The number and percentage of good-responders as a whole was 63.0% (400/635). The 5 prognostic factors contributed to statistically significant outcomes (p< 0.05), and the number and percentage of good-responders showing statistical significance were 53.1% (139/262) in the old-age group (odds ratio (OR) 2.1), 70.0% in the non-old-age; 19.2% (9/47) in the dermatophytoma group (OR 8.4), 66.5% (391/588) in the non-dermatophytoma; 35.3% (18/51) in the yellow-spike group (OR 3.5), 65.4% (382/584) in the non-yellow-spike; 19.5% (32/164) in the thick-nail group (OR 14.7), 78.1% (368/471) in the non-thick-nail; and 35.6% (36/101) in the involvement-more-than-50% group (OR 3.9), 68.2% (364/534) in the involvement-less-than-50%. 4. The 2 prognostic factors did not contribute to the outcomes statistically (p> 0.05) and the number and percentage of good-responders showing no statistical significance were 60.4% (58/96) in the onycholysis group, 63.5% (342/539) in the non-onycholysis; and 62.9% (44/70) in the lateral-involvement group, 63.0% (356/565) in the non-lateral-involvement. 5. The number and percentage of good-responders according to the number of prognostic factors were 92.6% (162/175) in 0-factor group, 62.3% (157/252) in 1-factor, 52.0% (64/123) in 2-factor and 30.9% (17/55) in 3-factor. CONCLUSIONS: Clinical outcomes of onychomycosis depend on what kind of prognostic factor or how many factors the patient has. Therefore, the clinical prognostic factors should be considered before starting the treatment for predicting prognosis and planning therapeutic modalities.