[A Rare Yeast: Cases of Rhodotorula mucilaginosa Infection Followed Up in a Tertiary University Hospital]

Rhodotorula species are yeasts that are common in the environment,but are not frequently encountered as an infectious agent in humans. Rhodotorula mucilaginosa, Rhodotorula glutinis and Rhodotorula minuta are the species that cause disease in humans. Although its isolation from mucosa is doubtful in terms of the presence of true infection, it is more frequently encountered in daily practice due to the increasing number of invasive procedures, immune system deficiencies caused by immunosuppressive drugs and diseases. R.mucilaginosa growth isolated from various clinical samples between 2000 and 2018 in a tertiary university hospital was presented in this case report. The first case was an 82-year-old man with chronic lung disease, hypertension, congestive heart failure and acute leukemia causing severe immunosuppression. Use of broad spectrum antibiotics, history of immunosuppressive therapy, presence of jugular catheter were the risk factors in this patient. R.mucilaginosa was isolated from blood culture while the patient was receiving fluconazole treatment for Candida albicans grown in urine culture and the patient died before starting the treatment. The second case was a 34-year-old female patient with congenital heart disease. Discharge was observed at the intracardiac defibrillator site of the patient, a temporary pacemaker was inserted, and she used broad spectrum antibiotics for a long time. When the yeast growth was reported in the blood culture, caspofungin treatment was initiated. Although the treatment was switched to amphotericin B lipid complex after the culture result was reported as R.mucilaginosa, the patient died after 12 hours. The third case was a 70-year-old woman with hypertension, dementia, diabetes mellitus and rheumatoid arthritis admitted to the intensive care unit due to cerebrovascular accident. She received different immunosuppressive treatments and had invasive procedures. R.mucilaginosa was isolated from the blood culture taken from the patient's catheter, and there was no growth in the blood culture obtained from the peripheral vein. Anidulafungin was started empirically, which was changed to amphotericin B lipid complex after the identification of the yeast. The patient died for various reasons 10 days after the antifungal treatment was stopped. Our last case was a 55-year-old woman with metastatic ovarian cancer and secondary ascites. Broad-spectrum multiple antibiotics were used and invasive procedures were performed. R.mucilaginosa and C.albicans were isolated from the urine of the patient who had a urinary catheter. No growth was detected from urine after changing the urinary catheter. Therefore, growths were evaluated as colonization, and fluconazole was administered for C.albicans due to the high risk of invasive infection. The patient was lost for different reasons. The development and diversity of the treatment methods lead to the emergence of some opportunistic infectious agents that were not observed previously. Rhodotorula species are one of the rare agents that have increased over the years. Rhodotorula species should be considered as the cause of an infection if no clinical response is obtained after echinocandin and/or fluconazole treatment in patients with long-term immunosuppression and invasive procedures. Data on clinical pictures, treatment responses, follow-up and treatment results of this rare yeast are still limited. This case series was presented to draw attention to the risk factors related to R.mucilaginosa infection/colonization, clinical characteristics of the patients, follow-up results and treatment options and to contribute to the literature.