JOHNS HOPKINS
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Department of Pathology
600 N. Wolfe Street / Baltimore MD 21287-7093
(410) 955-5077 / FAX (410) 614-8087
Division of Medical Microbiology
THE JOHNS HOPKINS MICROBIOLOGY NEWSLETTER Vol. 26, No. 16
Tuesday, September 11, 2007
A. Provided by Emily Luckman, Division of Outbreak Investigation, Maryland Department
of Health and Mental Hygiene.
There is no information available at this time.
B. The Johns Hopkins Hospital, Department of Pathology, Information provided by,
Terina Chen, M.D.
Case presentation: The patient is a 10 year-old African American female with history of acute
myeloid leukemia, status-post matched related bone marrow transplant in February of 2007.
Recently she was admitted for coagulase negative Staphylococcus bacteremia and was treated
with vancomycin. Blood cultures taken during this admission failed to demonstrate bacteremia.
However, yeast was isolated shortly after her discharge. The patient was recalled to Johns
Hopkins to begin antifungal therapy and address her vascular access. Ultimately, the yeast was
identified as Rhodotorula mucilaginosa and was recovered from at least four blood cultures
drawn over a five day period. The cultures became positive at between 2 and 6 days. The
patient’s central venous line was changed, and she began a course of liposomal amphotericin.
Throughout the second admission, she remained afebrile and asymptomatic.
Epidemiology: Rhodotorula species are ubiquitous saprophytic yeasts that may be recovered
from many environmental sources. These organisms are routinely encountered in bathrooms,
where they proliferate and form salmon pink films on shower curtains, toilets, bathtubs and
toothbrushes. Members of the genus Rhodotorula include R. mucilaginosa (formerly R.
rubra), R. minuta, and R. glutinis. Rhodotorula species colonize moist surfaces in humans,
including the skin, respiratory, genitourinary and gastrointestinal tracts. Occasionally, they
are true pathogens, particularly in immunocompromised hosts.
Laboratory aspects: Rhodotorula species may be compared to Cryptococcus species with
regards to morphology and biochemical properties. While their clinical significance is
disparate, both are round to oval budding yeasts with capsules. They similarly are urease
positive and do not ferment sugars. Distinguishing features of Rhodotorula include their
characteristic salmon pink or coral red pigmentation and their inability to assimilate inositol.
Also, Rhodotorula capsules are small in comparison to those of Cryptococcus.
Clinical Features & Treatment: Catheter-related fungemia appears to be one of the more
common Rhodotorula-related diseases. Rarely, a septic picture may develop. As with other
possible environmental contaminants, multiple positive cultures and relevant clinical signs or
symptoms suggest real fungemia. Cases of endocarditis, meningitis, ocular infections and
peritonitis have been reported. In a recent review of central venous catheter-associated
Rhodotorula fungemia (Tuon et al 2007), 87 of 88 patients had a known immunocompromised
state. Specifically, 78% of patients had underlying malignancy. The most frequently isolated
species was R. mucilaginosa (75%), and the reported overall mortality was 9.1%. Therefore,
while typically less virulent than more common pathogenic yeasts such as Cryptococcus and
Candida species, Rhodotorula infections may have serious implications.
Though treatment guidelines are not well-established due to the limited number of cases,
indwelling catheter removal in combination with antifungal therapy is prudent. In the available
literature, amphotericin B is the most often employed antifungal agent for Rhodotorula
infections. Rhodotorula species have demonstrated established resistance to fluconazole and
caspofungin. Susceptibility to voriconazole is variable. Proper identification of Rhodotorula
in clinical specimens is therefore important for appropriate management of significant
infections.
References:
1. Anatoliotaki M et al. “Rhodotorula species fungemia: a threat to the immunocompromised
host.” Clinical Laboratory 2003; 49(1-2):49-55.
2. Chung J et al. “Central venous catheter-related Rhodotorula rubra fungemia.” Journal of
Infection and Chemotherapy 2002; 8:109-10.
3. Diekema DJ. “Healthcare-associated fungal infections: beyond Candida and Aspergillus.”
Southern Medical Journal 2007; 100(2):130-1.
4. Hazen KC et al. “Candida, Cryptococcus, and other yeasts of medical importance” in Manual
of Clinical Microbiology, 9th edition. pp. 1762-88.
5. Neofytos D et al. “Rhodotorula mucilaginosa catheter-related fungemia in a patient with sickle
cell disease: case presentation and literature review.” Southern Medical Journal 2007;
100(2):198-200.
6. Tuon FF et al. “Central venous catheter-associated fungemia due to Rhodotorula species- a
systematic review.” Medical Mycology 2007; 45(5):441-7.