Research Information System
Thesis Type: Expertise In Medicine
Institution Of The Thesis: Gazi Üniversitesi, Tıp Fakültesi, Turkey
Approval Date: 2011
Student: ARZU ÇİFTÇİ
Supervisor: ESİN ŞENOL
Abstract:Candidemia is an important clinical entity, with high morbidity and mortality. It is responsible for 50-70 % of invasive candidiasis, and its diagnosis and treatment are difficult. Candida species are the fourth most commonly isolated pathogens in patients with nosocomial bloodstream infection in the United States of America (USA). Due to high mortality of candidemia, besides the prediction of patients at high risk for invasive candidiasis, preemptive or prophylactic approaches are required. Several studies have previously identified risk factors for the development of candidemia. This study is a laboratory-based, prospective observational study which was performed between 1 July 2009-1 July 2010 in Gazi University Medical Faculty Hospital. The frequency of candidemia, the risk factors associated with candidemia, the epidemiology, the distribution of species Candida spp. and their antifungal susceptibilities were determined to help to establish prophylactic and preemptive treatment strategies. Seventy-one patients of nosocomial candidemia were defined as the presence of positive blood culture for Candida species in at least 1 blood culture sample using traditional microbiological procedures if they occured 48 hours after hospital admission with concomitant signs and symptoms of infection according to the criteria of the Center for Disease Control and Prevention. All demographic characteristics, underlying diseases, risk factors, clinical signs and documentation of infectious, microbiological data, antifungal susceptibility, antifungal and antibacterial treatments and outcome patients with nosocomial candidemia were recorded to case report forms. The incidence of nosocomial candidemia was found to be 0.94 cases per 1000 hospital admission and the incidence density of nosocomial candidemia was determined as 0,021 per 1000 patient-days (0.21 per 10000 patient-days). Candida albicans was isolated in 34(47.9%), and non-Candida albicans in 37(52.1%) of the candidemia episodes. C. albicans was the most common species isolated (47.9%), followed by C.parapsilosis (16.9%), C.tropicalis (15.5%). C. glabrata (4.2%), C. krusei (4.2%), C.guilliermondii (% 4.2), C.kefyr ( 4.2%), C.lusitaniae (1.4%) and C.rugosa (1.4%). The most common risk factors associated with candidemia was the use of antibiotics (94.4%). The other risk factors were hospitalization in the last 1 month (93%), insertion of central venous catheter (70.4%), a history of hospitalization within the last 3 months (69.0%) and stay in intensive care unit (68.6%). While abdominal surgery, urethral catheter insertion and use of piperacillin tazobactam was found to increase the risk of C. albicans, a history of hospitalization within the last 3 months increased the risk of developing candidemia with non-Candida albicans. Seventy strains of Candida were tested for antifungal susceptibility to amphotericin B, fluconazole and voriconazole. Amphotericin B resistance was found to be 1.4% only 1 C.kefyr strains. For the total of strains fluconazole resistance was 20% which was involving 24.2% of C. albicans and 16.2% of non-Candida albicans strains. The results for voriconazole susceptibility testing were as follows; the resistance rate for the total of strains was 5.7%, for C. albicans 12.1% resistance was observed, however no resistance was observed for non-Candida albicans. Caspofungin resistance was found in 2% of 50 Candida species (only 1 C.albicans strain). Itraconazole has been studied for 69 strains and resistance was found in 40.6% of the C. albicans, 16.2% in non-Candida albicans strain. Crude mortality rate was found to be 33% for candidemia. The use of catheters and mechanical ventilation were associated with increase in mortality. The initiation of antifungal therapy before or after 48 hours, neutropenia, removal of central venous catheter, the type of Candida strain, was not found to be associated mortality rate in our study. As a result, the incidence of candidemia in our hospital was similar to the results of other studies conducted our country in the literature which some of them were performed. Although Candida albicans is found to be the most common cause of candidemia, non-Candida albicans were isolated from more than half of the cases in this study. When the common risk factors for candidemia in our study were taken into account, the incidence of candidemia can be reduced with the rational use of antibiotics, compliance with infection control measures, and avoiding unnecessary invasive interventions and medical treatments. Patients with defined risk factors can be monitored for the development of candidemia. Thus, early diagnosis and treatment of candidemia can be provided. In our study, resistance to fluconazole and itraconazole was found to be high. This result may lead to limited use of fluconazole which is frequently used for the treatment of candidemia, because of its low toxicity, and cost. In this study by analysing the epidemiology of candidemia regarding the distribution of Candida species and analysing the resistance rates of these species to commonly used antifungal agents in our institution we hope to be helpful in designing and implementing therapeutic strategies as prophylactic and preemptive therapies