Clinical and Microbiological Spectrum of Invasive Trichosporonosis at a Tertiary Care Institute: A Retrospective Observational Study

Abstract

Introduction: Invasive trichosporonosis was considered rare in the past decades, but it has emerged as an opportunistic pathogen causing invasive infections in immunocompromised patients. It can colonise various parts of the body, and it is important to differentiate between colonisation and infection. Moreover, knowledge of the epidemiology and risk factors associated with the disease is limited. Its inherent resistance to echinocandins poses a therapeutic challenge in treating patients. If not treated appropriately, it may lead to disseminated infections. Aim: To understand the clinical and microbiological spectrum of infections caused by Trichosporon spp. Materials and Methods: This retrospective observational study was conducted in the Department of Microbiology at Nizam’s Institute of Medical Sciences, Hyderabad, Telangana, India for a peroid of one year period from January 2019 to December 2019. The study analysed demographic data such as age, sex, risk factors, clinical features, microbiological diagnosis, treatment, and patient outcomes related to invasive trichosporonosis from the case records. The final sample size was 14 cases. Samples were processed for both aerobic and fungal cultures. The samples were inoculated into Chromogenic agar plates (bioMeriux), 5% sheep blood agar plates (bioMeriux), and Sabouraud dextrose agar. The plates were incubated at 37°C for 48 hours. Culture identification was performed using the Vitek® 2 compact system with the yeast panel YST, and antifungal susceptibility was determined by Broth Microdilution (BMD). Descriptive statistics were used for analysis, and categorical data were described as frequencies with percentages. The data was entered into a Microsoft Excel sheet and analysed using Statistical Packages for the Social Sciences (SPSS) Version 20.0. Results: During the study period, there were 14 cases of invasive trichosporonosis. The predominant age group was 60-70 years. Risk factors included the administration of broad-spectrum antibiotics in 13 (92.8%) of patients, followed by prolonged Intensive Care Unit (ICU) stay in 8 (57.1%) of the patients. Trichosporon spp. were isolated from urine in 10 (71.4%) cases, blood in 2 (14.2%) cases, and tissue in 2 (14.2%) cases. Trichosporon asahii was the predominant species isolated in 12 (85.7%) patients. All isolates were sensitive to voriconazole and amphotericin B. Mortality was reported in 5 (35.7%) of the patients. Conclusion: In present study, Trichosporon spp. was predominantly isolated from urine in the majority of patients. The pathogen was isolated from patients with various risk factors. Hence, proper identification of the pathogen, understanding its clinical significance, and determining antifungal susceptibility would aid in the appropriate management of patients.