title: Can serums be replaced by Mueller-Hinton agar in germ tube test?
abstract: BACKGROUND
  The germ tube test (GTT) is inexpensive, easy, and well-defined test that differentiates Candida albicans (excluding Candida dubliniensis and Candida africana) from other species. The aim of this study was to evaluate various serums (i.e., human, rabbit, horse, and fetal bovine serum) used in the GTT and Mueller-Hinton agar (MHA).
  
  
  METHODS
  Fifty species isolated from various clinical samples that were defined as C. albicans by both conventional and DNA sequence analysis methods were included in the study. One to two colonies of C. albicans were mixed into 0.5-1 ml of fetal bovine serum, horse serum, rabbit serum, and human serum. Serums and MHA were incubated at 37°C for GTT. They were removed from the incubator and evaluated after 30 min, 1 h, 2 h, and 3 h of incubation. The GTT was accepted to be positive only if germ tube was 1/2 the width and 3 times the length of the parent yeast cell and with no constriction at the point of origin.
  
  
  RESULTS
  When the use of serums and MHA for GTT was statistically evaluated, according to the positive scoring, the best results were obtained with MHA and with rabbit, horse, and fetal bovine serum, respectively. The best definition over time statistically was the third hour.
  
  
  CONCLUSIONS
  It is suggested that inexpensive MHA is a fast, appropriate, and reliable medium for the probable diagnosis of GTT and C. albicans; however, additional studies are still needed to define other Candida species.
authors.affiliation: Department of Clinical Microbiology Faculty of Medicine, Erciyes University, Kayseri, Turkey.
authors.forename: M A
authors.initials: MA
authors.lastname: Atalay
authors.affiliation: Department of Clinical Microbiology Faculty of Medicine, Erciyes University, Kayseri, Turkey.
authors.forename: A N
authors.initials: AN
authors.lastname: Koc
authors.affiliation: Department of Clinical Microbiology Faculty of Medicine, Erciyes University, Kayseri, Turkey.
authors.forename: O M
authors.initials: OM
authors.lastname: Parkan
authors.affiliation: Department of Clinical Microbiology Faculty of Medicine, Erciyes University, Kayseri, Turkey.
authors.forename: G
authors.initials: G
authors.lastname: Aydemir
authors.affiliation: Department of Biostatistics, Faculty of Medicine, Erciyes University, Kayseri, Turkey.
authors.forename: F
authors.initials: F
authors.lastname: Elmali
authors.affiliation: Department of Clinical Microbiology, Faculty of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: H
authors.initials: H
authors.lastname: Sav
mesh_terms: D000362:Agar; D000818:Animals; D002176:Candida albicans / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D002177:Candidiasis / Q000175:diagnosis* / Q000382:microbiology*; D002417:Cattle; D003470:Culture Media; D006736:Horses; D006801:Humans; D058889:Molecular Typing; D060885:Multiplex Polymerase Chain Reaction; D016533:Mycological Typing Techniques / Q000379:methods; D011817:Rabbits; D012680:Sensitivity and Specificity; D044967:Serum; D013045:Species Specificity
chemical_list: D003470:Culture Media; D000362:Agar