JOURNAL OF CLINICAL MICROBIOLOGY, Dec. 2010, p. 4677–4679
Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Vol. 48, No. 12
Candida bracarensis Bloodstream Infection in an
Thomas A. Warren,1Lisa McTaggart,2Susan E. Richardson,1,2,3and Sean X. Zhang1,2*
Department of Laboratory Medicine and Pathobiology, University of Toronto,1Public Health Laboratories, Ontario Agency for
Health Protection and Promotion,2and Division of Microbiology, Hospital for Sick Children,3Toronto, Ontario, Canada
Received 15 July 2010/Returned for modification 30 August 2010/Accepted 21 September 2010
Candida bracarensis is a recently described Candida species which is phenotypically similar to Candida
glabrata. A case of C. bracarensis bloodstream infection in a bone marrow transplant patient is described and
confirms this organism as an opportunistic human pathogen. The organism can be distinguished from C.
glabrata by its white color on CHROMagar and by DNA sequence analysis using D1/D2 and internal tran-
scribed spacer (ITS) primers.
A 50-year-old male underwent a matched related-donor
bone marrow transplant after a diagnosis of chronic lympho-
cytic leukemia made 7 years previously. The patient’s post-
transplant course was complicated by significant graft-versus-
host disease (GVHD) of the skin, liver, and bowel. Four
months after transplant, the GVHD necessitated admission to
hospital and he was treated with cyclosporine and corticoste-
roids. In hospital, he had multiple infectious complications,
including herpes simplex virus mucositis and cytomegalovirus
viremia, treated with antiviral therapy. Seven weeks after ad-
mission to hospital, the patient developed respiratory failure
and sepsis, which necessitated transfer to the intensive care
unit (ICU). Klebsiella pneumoniae was cultured from both the
urine and the blood, and Staphylococcus aureus was cultured
from bronchoalveolar lavage fluid. He was treated with appro-
priate antibiotic therapy.
Three weeks after admission to the ICU, two blood cultures
became positive, and yeast cells were seen on the Gram stain.
After 24 h of growth, small white colonies were seen on blood
and chocolate agar media. A wet prep showed budding yeast
cells, and a germ tube test was negative. On Saboraud’s agar,
colonies appeared white and creamy. On cornmeal agar, hy-
phae or pseudohyphae were not observed microscopically.
Both isolates produced white colonies on BBL CHROMagar
(BD diagnostics, Maryland). Biochemically, the isolates were
positive for the rapid trehalose assay (Remel, Lenexa, KS) and
positive for assimilation of lysine and glucose (Table 1). Iden-
tification using the API 20C AUX system (bioMe ´rieux, Inc.,
NC) showed a low-percentage identity match with C. glabrata
(?50%). Thus, molecular analysis was applied to further char-
acterize these strains.
Both isolates were negative as determined by a C. glabrata-
specific PCR, with gel electrophoresis endpoint detection using
primers targeting the internal transcribed spacer (ITS) region
and PCR conditions described previously (8) (Table 1). The
ITS1-5.8S-ITS2 region and the D1/D2 region of 26S ribosomal
DNA (nucleotides 63 to 642) were amplified and sequenced.
PCRs were conducted using the Phire Hot Start DNA poly-
merase kit (New England Biolabs, Massachusetts) according to
the manufacturer’s instructions and using the following ampli-
fication conditions: 98°C for 30 s, followed by 35 cycles of 98°C
for 5 s, annealing temperature (see below) for 5 s, and 72°C for
20 s, followed by a final extension of 72°C for 1 min. The ITS
region was amplified using the primers ITS-1 (5?-TCCGTAG
GTGAACCTGCGG-3?) and ITS-4 (5?-TCCTCCGCTTATTG
ATATGC-3?) (12) and an annealing temperature of 56°C,
while amplification of D1/D2 required the primers NL-1 (5?-
GCATATCAATAAGCGGAGGAAAAG-3?) and NL-4 (5?-G
GTTCCGTGTTTCAAGACGG-3?) (9) and an annealing tem-
perature of 60°C. PCR amplicons were sequenced using the
ABI 3130xl genetic analyzer (Life Technologies, Carlsbad,
CA) according to the manufacturer’s instructions. Sequence
alignment and cluster analysis of the ITS and D1/D2 regions of
the clinical isolates along with the type strains C. nivariensis
NRRL Y-48269T, C. bracarensis NRRL Y-48270T, C. glabrata
NRRL Y-65T, and C. albicans NRRL Y-12983Twere per-
formed by the neighbor-joining (NJ) method using the Bio-
Numerics v.6.0 software program (Applied Maths, Inc., Austin,
TX). The ITS and D1/D2 sequences of the clinical isolates
were identical to each other and showed 98.7% and 99.7%
similarities, respectively, to the type strain of C. bracarensis.
Furthermore, NJ phylogenetic analysis of both D1/D2 (Fig. 1)
and ITS (data not shown) demonstrated the clinical isolates
clustering more closely with C. bracarensis than any of the
other type strains. Based on the results from phenotypic and
molecular analysis (Table 1 and Fig. 1), we identified the iso-
lates as C. bracarensis.
Antifungal drug susceptibilities of the two isolates were
tested using the Yeast YO9 panel (Trek Diagnostic, Cleveland,
OH). Both isolates were susceptible to all the drugs tested
except for itraconazole, to which a category of “susceptible
dose dependent” was assigned (Table 2). The patient was
treated with a 2-week course of caspofungin. Subsequent blood
* Corresponding author. Present address: Division of Medical Mi-
crobiology, the Johns Hopkins University School of Medicine, 600
North Wolfe St., Meyer B1-193, Baltimore, MD 21287. Phone: (410)
955-5077. Fax: (410) 614-8087. E-mail: firstname.lastname@example.org.
?Published ahead of print on 29 September 2010.