Interactions of Trichophyton mentagrophytes and micrococci on skin culture

Generalized skin reaction following tinea pedis (dermatophytids)

An 11-year-old boy presented with inflamed tinea pedis followed by a generalized id type skin eruption, with disappearance of the rash after treatment of the mycotic foot lesions. The pathogenesis of this process is not precisely known. Fungal infection was not detected from the generalized skin lesions. Various clinical forms of dermatophytid reaction are discussed.

Microbial ecology of interdigital infections of toe web spaces

The microbial flora of normal and macerated interdigital toe web spaces was qualitatively and quantitatively identified in 77 patients. Dermatophyte fungi were recovered from 11% of normal patients compared with a 31% recovery from patients with macerated interspaces. Macerated interspaces were characterized by a greater recovery of organisms with pathogenic potential, with Staphylococcus aureus recovered from 36% of patients, Micrococcus sedentarius in 37%, Brevibacterium epidermidis in 54%, Corynebacterium minutissimum in 69%, and Pseudomonas species in 26%. The bacterial flora of macerated interspaces showed a significantly higher incidence of resistance to multiple antibiotics, and the recovery of antibiotic-resistant bacteria correlated with the recovery of dermatophytes that produce penicillin-like substances. The results of this study support the hypothesis that overgrowth of the resident bacterial population determines the severity of interdigital toe-web infections.

Ketoconazole (R 41 400) in the treatment of dermatophyte infections: a clinical, mycological, and morphological study

Ketoconazole (100 mg, orally, once daily) was investigated in nine patients with extensive dermatophyte infections. After treatment ranging between one week and three months, clinical cures (healing of lesions and negative cultures) were observed in all cases. In vitro growth of Trichophyton rubrum, T. mentagrophytes, and T. verrucosum isolated from infected skin scales were completely inhibited by concentrations of ketoconazole of 10 microgram/ml and above. No evidence for the development of drug resistance was obtained from regular in vitro sensitivity tests.

Interactions between dermatophyte fungi and staphylococci or Brevibacterium in vitro

Interactions between dermatophyte fungi and staphylococci or brevibacteria on a new skin-based culture medium are described. Penicillin production by the fungus selects penicillin resistant S. aureus or B. epidermidis. Fungi are inhibited by brevibacteria but not by the staphylococci. "Keratolysis" by fungi may contribute to the growth nutrients of staphylococci.