Comparison of Guizotia abyssinica seed extract (birdseed) agar with conventional media for selective identification of Cryptococcus neoformans in patients with acquired immunodeficiency syndrome.
Growth of Cryptococcus neoformans from the sputum of patients with acquired immunodeficiency syndrome may be obscured by oral contamination with Candida albicans on conventional media. We prospectively compared direct plating of sputum and urine onto birdseed agar and compared birdseed agar plating with plating onto Mycosel and Sabouraud dextrose agar cultures. Thirty-two sputum and three urine specimens were compared. C. neoformans was isolated from five specimens. In two specimens, one of sputum and one of urine, C. neoformans was detected only on the birdseed agar plate because of overgrowth on the conventional media by C. albicans. C. neoformans produced dark colonies on birdseed agar, unlike C. albicans, which produces white colonies. The use of birdseed agar as the primary culture medium for sputum and urine specimens from patients with acquired immunodeficiency syndrome increases sensitivity for C. neoformans.
Denning
D W
DW
Department of Pathology, Santa Clara Valley Medical Center, San Jose, California.
Stevens
D A
DA
Hamilton
J R
JR
D000163:Acquired Immunodeficiency Syndrome / Q000150:complications; D000362:Agar; D003453:Cryptococcosis / Q000150:complications / Q000175:diagnosis* / Q000382:microbiology; D003455:Cryptococcus neoformans / Q000302:isolation & purification*; D003470:Culture Media; D003951:Diagnostic Errors; D005069:Evaluation Studies as Topic; D006801:Humans; D009172:Mycology / Q000379:methods*; D009894:Opportunistic Infections / Q000150:complications / Q000175:diagnosis; D012639:Seeds; D013183:Sputum / Q000382:microbiology; D014556:Urine / Q000382:microbiology
D003470:Culture Media; D000362:Agar