Rhoda W. Benham

Cryptococcosis and blastomycosis.

The two diseases which form the title of this report were described for the first time in 1894: one from Europe, the other from the United States. These two, with a number of other distinct diseases, did in the past and in some cases still do appear in the literature under the name “blastomycosis.” The resulting chaos in terminology has been difficult to overcome. It originated with the practice of referring to organisms reproducing by buds or blastospores as “Blastomycetes,” and the conditions in which they occurred as “blastomycosis.” Since the etiological agent in many different deep-seated fungus infections appears in the tissues or exudate from the lesions in the form of oval or rounded budding cells, they were often erroneously described as blastomycosis. Cultures proved, however, that a number of different fungi were involved and that a number of distinct diseases had been described under one name. Some workers went so far as to suggest that blastomycosis was a disease entity due to a plurality of species. Castellani,’ for one, stated in 1920 that “Blastomycosis is a term generally applied to affections due to fungi of the genera Saccka~oinyces, Crypiococcus, Monilia, Oidium, and Coccidioides.” As a result, then, of cultural studies and of a careful consideration of the characteristic appearance of the fungus in the parasitic state, we now have a number of deep-seated fungus infections described under their respective names, and the term blastomycosis has become more limited in scope. The general practice is to restrict its use to the disease first described as such, namely, that of Gilchrist. Although Castellani2 and Conant3 have pointed out that the name is not suitable, neither advises dropping it. It has come to stand for a definite entity in medical mycological literature and has not much significance otherwise. History shows us that the name Blasfomyces was first given by Constantin and Rolland4 (1888) to a fungus which they isolated from dung and described as a new species. It is a filamentous, branched form with conidia a t the ends of short branches. These conidia or buds, as these authors called them, in turn produce so-called secondary buds a t many points, and these, still others, until each fruiting branch transforms itself into a powdery spore mass. This fruiting mass is yellow to sulphur color, passing to redorange and sometimes green. Only one species is known, Elastomyces luteus. This is listed as being in the collection a t Baarn, but I have not as yet obtained a subculture. Just what it is would be anyone’s guess, but, in the illustrations, the conidia are not unlike those of some of the gymnoascus forms, or of some of the dermatophytes. Certainly it is not a yeast-like fungus. In Clements and Shear’s5 key to Saccardo’s classification me find it defined as follows: “Hyphae elongated and distinct from conidia. Conidia bearing hyphae of two sorts, the upright alone den ticulate.”

Cryptococcus neoformans: "An Ascomycete".

Conclusions These observations would seem to indicate that Cryptococcus neofor-mans and Lipomyces starkeyi may be one and the same organism, and that it is frequently isolated from the soil. Thus another of the fungi pathogenic to man may take its place in that large and important class of the Ascomy-cetes. It remains but to find ascospores in a strain isolated from a human case. A large number of strains from various sources must be studied and comparisons made both as to virulence and other characteristics. For absolute proof that the structure represents a true ascus one would need to know how the spores are delimited. The final and complete story will be told only by cytological investigations.

Cultural Characteristics of Pityrosporum ovale—A Lipophylic Fungus. Nutrient and Growth Requirements

Conclusions The Pityrosporum ovale grows in the presence of inorganic salts, glucose and oleic acid. The addition of asparagin accelerates growth and increases the final yield. Thiamin and pyridoxin accelerate development but are not essential to the growth of this fungus under the conditions studied.

Pityrosporum ovale-a lipophilic fungus. Thiamin and oxaloacetic acid as growth factors.

Summary and Conclusions Thiamin when added to a basal medium containing KH2PO4, MgSO4 and with asparagin or NH4Cl causes an increase in the growth of Pityrosporum ovale. With asparagin the increase is much greater than with NH4Cl. However, if ethyl oxalacetate replaces the thiamin, growth in the NH4Cl medium is just about equal to that in the asparagin medium. The addition of thiamin to the medium containing oxalacetate does not cause any further increase in growth. It would seem then that NH4Cl and ethyl oxalacetate can be substituted for asparagin and thiamin in the cultivation of Pityrosporum ovale. It appears that if a suitable keto acid is supplied neither thiamin nor an amino acid is necessary. On the other hand, the asparagin may furnish both the carbon and nitrogen source needed by the organism, yielding ammonia and a carbon skeleton, probably oxalacetate. Thiamin increases growth when added to the asparagin by hastening the production of the carbon skeleton in some way. When this carbon skeleton is supplied as oxalacetate, thiamin is no longer necessary.