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Background: A reference method for dermatophyte in vitro susceptibility testing is lacking. With the advent of new antimycotics, susceptibility testing has received increasing attention as an important laboratory tool for aiding the selection of appropriate drug therapy., Methods: One hundred strains of Trichophyton rubrum were tested against four antifungal agents, itraconazole, clotrimazole, ketoconazole and terbinafine, by using a modification of the proposed standard M38-P of the National Committee for Clinical Laboratory Standards and two types of standardized inocula, 1.4 x 10(4) and 5 x 10(3) CFU/ml., Results: Terbinafine was revealed to be the most effective antifungal drug. Of the three azole derivatives tested, clotrimazole showed the highest antifungal activity, while the minimum inhibitory concentrations (MICs) of itraconazole and ketoconazole were similar. Inoculum size did not affect the MIC of any of the antifungal agents tested., Conclusion: Our preliminary data provide promising results for the development of a reference method for dermatophyte susceptibility testing based on the microdilution technique, although more dermatophytes should be tested and the method evaluated in different laboratories., (Copyright 2000 S. Karger AG, Basel)

From October 1994 to December 1996, a prospective study was undertaken in 10,000 unselected school children in Madrid, aged between 2 and 16 years (mean +/- SD 8.5 +/- 3.6 years). Fifty-two (0.52%) (including 13 immigrants from Africa) had dermatophytes in the scalp: 33 (0.33%) (including 10 immigrants from Africa) had tinea capitis and 19 were scalp carriers. Almost half of the symptomatic cases were caused by Trichophyton tonsurans (12 of 33 cases) and Microsporum canis (16 of 33 cases). T. tonsurans (13 of 19 cases) was the predominant species in the scalp carriers. Twenty-four per cent of the subjects with tinea capitis and 42% of the asymptomatic scalp carriers also had ringworm in other body sites. There was a significantly higher occurrence of tinea capitis (P < 0.001) (particularly due to T. tonsurans: P < 0.001) and of asymptomatic scalp carriers (P < 0.05) (particularly due to anthropophilic species: P < 0.01) in the immigrant population from Africa.

We have reviewed all the dermatophytoses diagnosed in Galicia during four consecutive 9-year periods 1951-86 and 1987. From 4571 patients, we isolated 3351 fungal strains belonging, in decreasing order of frequency, to the following dermatophyte species: Microsporum canis (25.5%), Trichophyton rubrum (24.6%), T. mentagrophytes (21.4%), Epidermophyton floccosum (11.8%), M. gypseum (5.2%), T. tonsurans (3.9%), T. verrucosum (3.1%), T. schoenlenii (2.5%), T. violaceum (1.2%), T. mengninii (0.3%), M. audouinii (0.2%), T. equinum (0.1%) and T. soudanense (0.1%). Tinea capitis has diminished in frequency since 1951, though there was been a slight increase since 1978; M. canis has always been the most common agent, and between 1951 and 1959 T. schoenleinii was also very frequent but is no longer found. The frequency of tinea corporis, on the other hand, has experienced a considerable increase. Its most common causal agents in the last few years have been T. mentagrophytes, M. canis and T. rubrum. Until 1977 the most common tinea cruris dermatophyte was E. floccosum, but since then it has been T. rubrum. The commonest tinea pedis dermatophytes have been T. rubrum and T. mentagrophytes. Tinea unguium and tinea barbae have been the most frequent dermatophytoses, and their commonest causal agents T. rubrum and T. mentagrophytes respectively. We have documented the distribution of the various causal agents by location of the lesions, age and source of the patients (private or National Health Service patients), and we have compared the results with those obtained in other regions of Spain.

We have had the opportunity to study an dermatophyte isolated from the face of a woman, as a result of a fall on the ground. We identified the strain as Trichophyton proliferans whose characteristics, together with a review of the works published about this dermatophyte, lead us to believe that we are dealing with an independent species and not a synonym of T. mentagrophytes var. erinacei.

A case of tinea faciae caused by Trichophyton equinum affecting a 5-year-old boy is described. The boy had ridden a pony a month earlier and responded to a 6-week course of treatment with oral and topical terbinafine. [ABSTRACT FROM AUTHOR]