Retrospective study of mycotic infections of the feet due to dermatophytes and moulds in Siena from 1993 to 2002 [Infezioni micotiche dei piedi da dermatofiti e muffe a Siena. Studio retrospettivo dal 1993 al 2002]

Aim. The aim of this paper is to evaluate the occurrence of mycotic infections due to dermatophytes and moulds, diagnosed at the Mycology Unit of the Dermatology Department, Siena, the only unit in Siena Province offering mycological examination, from 1993 to 2002. Methods. Five hundred and thirthy-nine patients with suspected mycotic infection underwent mycological examination. Diagnosis was based on direct microscope observation and culture of pathological material on Sabouraud dextrose agar with CAF and cycloheximide and on Sabouraud dextrose agar with CAF only. Results. Dermatophyte infections were found in 190 cases (112 males, 78 females, age 5-71 years, mean age 38) and mould infections in 13 cases (9 males, 4 females, age 28-52 years, mean age 37). With regard to dermatophyte infections, Trichophyton rubrum was isolated in 71% of cases, Trichophyton mentagrophytes in 21% and Epidermophyton floccosum in 8%. The infections manifested as intertrigo in 87%, tinea pedis bullosa in 8%, "moccasin foot" in 4% and intertrigo plus bullae in 1%. With regard to mould infections, Fusarium was isolated in 11 cases (Fusarium oxysporum in 10 cases and Fusarium solani in 1). The clinical picture was interdigital intertrigo with areas of whitish, macerated and eroded skin. Scytalidium hyalinum was isolated in 2 cases. The clinical manifestations were "moccasin foot" in 1 case, plantar and interdigital desquamation in the other. Conclusion. Mycotic infections of the feet are usually caused by dermatophytes, rarely (7%) by moulds. The most frequent site is between toes IV and V. Predisposing factors are warm maceration, occlusion and, in mould infections, contact with soil. When mycotic infections of the feet are suspected, it is advisable to perform mycological examination with culture of pathological material not only on Sabouraud dextrose agar with CAF and cycloheximide but also on Sabouraud dextrose agar with CAF only. Long-standing monitoring of mould infections is necessary because they are dangerous in immunodepressed patients.