Microsporum Gypseum as Parasite in Man and Saprophyte Isolated From Soil

Abstract

Starting from investigations made by Ajello, Gordon, Georg, Vanbreuseghem and others, regarding the saprophytic life of pathogenic fungi, the authors have searched for pathogenic dermatophytes from soil samples taken in an area in Bosnia, where ringwonn of the scalp is endemic.

Using 120 samples of soil tested after the method of Vanbreuseghem and by suspension, the authors succeeded in establishing existence of M. gypseum in 5 samples, while other dermatophytes-those that cause the endemic ring-worm of the scalp (T. violaceum, T. schbnleini) in this area so far have not been isolated. In addition, a case of 9-year old boy, infected with M. gypseum is described; however the source of infection could not be established.

Taking note of the fact, that Cajkovac has isolated the same parasite in men 22 times, this means that so fai' there have been 23 known cases of M. gypseum isolation in Yugoslavia. On the basis of review of recent literature the Ajello’s table has been complemented: the data available up to the, present now reveal 322 known cases of isolates of M. gyspeum.

By comparing the growth of M. gypseum as a saprophyte (in soil and culture) and as a parasite (on human hair), the authors were able to establish a marked difference in behaviour of this dermatophyte depending on wheter it exists as a saprophyte or as a parasite, and wheter the substratum is a sterile on unsterile soil.

It was found that M. gypseum as a sapropyte (either from soil or in
culture) grows both in sterile and in unsterile soil. On the other hand, M.
gypseum as a parasite on human haii- behaves differently when using as the medium unsterile soil. Unsterile soil has an inhibitory action upon the growth of M. gyipseum in its parasitic State. However, the protruding part of the hair put in unsterile moistened soil serves as a good substratum for the development of M. gypseum in its sapropytic life, producing abundant morphological forms, as seen when it grows as a saprophyte, while that part of the hair, which was covered with soil, remains unchanged. It therefore follows that unsterile soil brings about a certain inhibitory effect upon M. gypseum in its parasitical life, but not so when the dermatophyte shows biologically conditioned morphologic forms of saprophytic life.

A suggestion is made for a classification of fungi, as regards biology and oecology, into four developmental groups, which are pertinent to the pathology of man and animals, according to their parasitic and saprophytic life respectively.