The morphology of the pseudoparasitic phase of some dermatophytes

Summary

The morphology of the pseudoparasitic life phase (continuous shake culture) of several dermatophytes is described. There was a strong resemblance between the forms developing in the early stages of this phase and those of the parasitic phase as found in clinical lesions. Propagation of the organisms mainly took place by the breaking up of hyphae into numerous arthrospores. During the later stages of development, however, structures not found in the parasitic phase appeared but which resembled those found in the saprophytic phase (stationary culture). This was especially true forE. floccosum, T. violaceum andT. schoenleini. The complete absence of microconidia in all species, and of spirals inT. mentagrophytes andE. floccosum was noted.

In addition to the different rates of growth certain microscopic features, most pronounced withT. violaceum, T. schoenleini andE. floccosum, seemed to permit differentiation of the various species in their pseudoparasitic life phase.