| Abstract: | Candida albicans is often isolated from clinicalsamples, thus its presumptive differentiation from other species of the samegenus can be based on its ability to form the germ tube in human serum.Nevertheless, there are two other species that share this characteristic:C. dubliniensis and C. africana. The aimof this study was to compare four different substrates to perform the germ tube(GT) test. The Candida spp. isolates were identifiedusing a manual system (135 C. albicans, 24 C.tropicalis and one C. dubliniensis). The germtube test was performed with fresh, previously frozen serum and Mueller-Hinton(MH) broth and agar. GT was observed in 96%(130/136) of the isolates through the fresh serum technique,94% (128/136) through previously frozen serum, 92%(125/136) in MH agar, and 90% (122/136) in MHbroth. The sensitivity of each test was higher than 90%, with 100%specificity. Both the MH agar and broth were able to identify the truepositives, and false positives were not found. However, some C.albicans isolates were not identified. MH agar and broth may beused in laboratory for the rapid presumptive identification of C.albicans, as an alternative method for germ tube test. |
