Cryptococcus humicolus Species

Colonies on Sabouraud dextrose agar at 25°C are cream to yellow, glistening to dull, and smooth to rugose.

On cornmeal following 72 hours incubation at 25°C, both true and pseudohyphae are abundantly formed. Both types of hyphae appear wavy with branching occurring at narrow angles to the main hyphae.

This isolate is urease positive but fails to grow at 37°C and gives a negative nitrate reaction. The type strain was isolated from soil. DNA analysis suggests that this species is closely related to members of the genus Trichosporon [1270]. This agent has been reported as a cause of systemic cryptococcus in a 7.5 year-old HIV negative child [2096]. Isolates received in the FTL have been recovered from abdominal fluid, blood in a liver-small bowel transplant patient, and from skin.

AMB	FLU	ITRA	VORI	POSA
0.125 µg/ml=1	0.5 µg/ml=2	<0.015 µg/ml=2	0.03 µg/ml=2	0.03 µg/ml=1
0.25 µg/ml=2	2.0 µg/ml=2	0.03 µg/ml=1	0.06 µg/ml=1
	64 µg/ml=1	0.25 µg/ml=1	0.125 µg/ml=1

Drug/N	AMB/3	FLU/5	ITRA/4	POSA/1	VORI/4
MIC Range	0.125-0.25	0.5-64	<0.015 -0.25	0.03	0.03-0.125

* Fungus Testing Laboratory unpublished data (CLSI M27-A2)

PubMed

GenBank

References

1270. Kurtzman, C. P., and J. W. Fell (ed.). 2000. The Yeasts. A Taxonomic Study. Elsevier Scientific B.V., Amsterdam, The Netherlands.

2096. Shinde, S. M., K. S. Vanarse, and A. N. Pandit. 2004. Systemic humicolus cryptococcosis. Indian Pediatr. 41:1162-4.