might have had a urinary tract infection caused by C. albi-
cans at that time. Clinicians should be aware that the reason
for urinary retention might be fungus balls for patients with
Conﬂict of interest
1 Shimada S, Nakagawa H, Shintaku I et al. Acute renal failure as a result of
bilateral ureteral obstruction by Candida albicans fungus balls. Int. J. Urol.
2006; 13: 1121–2.
2 Wang L, Ji X, Sun GF et al. Fungus ball and emphysematous cystitis sec-
ondary to Candida tropicalis: a case report. Can. Urol. Assoc. J. 2015; 9:
3 Thomas L, Tracy CR. Treatment of fungal urinary tract infection. Urol. Clin.
North Am. 2015; 42: 473–83.
4 Fisher JF, Sobel JD, Kauffman CA et al. Candida urinary tract infections —
treatment. Clin. Infect. Dis. 2011; 52(Suppl 6): 457–66.
5 Sobel JD, Kauffman CA, McKinsey D et al. Candiduria: a randomized, dou-
ble-blind study of treatment with ﬂuconazole and placebo. The National Insti-
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Infect. Dis. 2000; 30:19–24.
6 Wada K, Uehara S, Yamamoto M et al. Clinical analysis of bacterial strain
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Editorial Comment to Management of fungus balls as a result of Candida albicans
Fungus balls, also known as fungal bezoars, is a colonization
of a cavity by an aggregate of fungal mycelia. Among fun-
guria cases, Candida species make up the majority of patho-
gens, representing >95% of positive urine culture results.
Thomas et al. reported that strong risk factors for funguria
included diabetes mellitus, indwelling catheter use, recent
antibiotic use and urinary tract disease. They also reported
that the possible risk factors included pregnancy, malignancy,
immunosuppression, recent surgery and renal transplant.
Sobel et al. reported that predictive factors for candiduria
and Candida urinary tract infections included diabetes melli-
tus, urinary tract infection, kidney transplantation, advanced
age, medical device of the urinary tract, female sex, bacteri-
uria, prolonged hospitalization, congenital abnormalities of
the urinary tract, intensive care unit admission, structural
abnormalities of the urinary tract, use of broad-spectrum
antibiotics, bladder dysfunction, urolithiasis and urinary
Candida species show unique behavior in their ability to
both colonize and cause invasive disease in the urinary tract.
The article by Hiyama et al.
follows another case report of
fungal bezoar of the urinary bladder as a result of Candida
A 73-year-old man, with a past medical history of
high blood pressure, complained of a 2-week history of fever,
pyuria and difﬁculty in urination. The patient had never
complained of any lower urinary tract symptoms before this
episode. He subsequently developed acute urinary retention.
Based on a clinical diagnosis of fungal infection of the uri-
nary bladder, empirical treatment of intravenous ﬂuconazole
was carried out. The histological examination revealed a sub-
stantial amount of yeast and pseudohyphae, and the fungal
culture examination became positive for Candida tropicalis.
Currently, there are no clear guidelines on the management
of patients with Candida urinary tract infections. Although
Candida bezoars are extremely rare in the urological litera-
ture, it is imperative that recommendations based on quality
data are obtained to optimize treatment. Clinicians should be
aware that the differential diagnosis for urinary retention
might be fungal bezoar for patients with risk factors.
Yazawa Clinic, and
Department of Urology, Keio
University School of Medicine, Tokyo, Japan
Conﬂict of interest
Fig. 1 (a) Abdominal ultrasound showed
spherical masses in the patient’s bladder. (b)
Cystoscopy showed that spherical white masses
ﬁlled the bladder.
© 2018 The Japanese Urological Association