Timing of treatment for nonneutropenic patients colonized with Candida

Diagnosis and therapy of Candida infections: joint recommendations of the German Speaking Mycological Society and the Paul-Ehrlich-Society for Chemotherapy

Invasive Candida infections are important causes of morbidity and mortality in immunocompromised and hospitalised patients. This article provides the joint recommendations of the German-speaking Mycological Society (Deutschsprachige Mykologische Gesellschaft, DMyKG) and the Paul-Ehrlich-Society for Chemotherapy (PEG) for diagnosis and treatment of invasive and superficial Candida infections. The recommendations are based on published results of clinical trials, case-series and expert opinion using the evidence criteria set forth by the Infectious Diseases Society of America (IDSA). Key recommendations are summarised here: The cornerstone of diagnosis remains the detection of the organism by culture with identification of the isolate at the species level; in vitro susceptibility testing is mandatory for invasive isolates. Options for initial therapy of candidaemia and other invasive Candida infections in non-granulocytopenic patients include fluconazole or one of the three approved echinocandin compounds; liposomal amphotericin B and voriconazole are secondary alternatives because of their less favourable pharmacological properties. In granulocytopenic patients, an echinocandin or liposomal amphotericin B is recommended as initial therapy based on the fungicidal mode of action. Indwelling central venous catheters serve as a main source of infection independent of the pathogenesis of candidaemia in the individual patients and should be removed whenever feasible. Pre-existing immunosuppressive treatment, particularly by glucocorticosteroids, ought to be discontinued, if feasible, or reduced. The duration of treatment for uncomplicated candidaemia is 14 days following the first negative blood culture and resolution of all associated symptoms and findings. Ophthalmoscopy is recommended prior to the discontinuation of antifungal chemotherapy to rule out endophthalmitis or chorioretinitis. Beyond these key recommendations, this article provides detailed recommendations for specific disease entities, for antifungal treatment in paediatric patients as well as a comprehensive discussion of epidemiology, clinical presentation and emerging diagnostic options of invasive and superficial Candida infections.

Combined Assessment of β-d-Glucan and Degree of Candida Colonization before Starting Empiric Therapy for Candidiasis in Surgical Patients

The purpose of the study was to investigate whether examination for plasma beta-D-glucan, a cell wall constituent of fungi, is useful for selecting surgical patients with Candida colonization who would benefit from empiric antifungal therapy. We administered fluconazole to postoperative patients with Candida colonization who have risk factors for candidemia and complained of persistent fever despite prolonged antibacterial therapy. We then analyzed the clinical outcomes regarding the number of sites colonized with Candida spp. and plasma beta-D-glucan. Of the 32 patients positive for alpha-D-glucan, 15 (46.9%) responded to the empiric therapy; only 9% of those who were negative responded (p < 0.01). In the multiple logistic regression analysis, being positive for alpha-D-glucan was a significant factor predicting response, with an adjusted odds ratio of 12.9 in patients with Candida colonization [95% confidence interval (CI) 2.07-80.73) (p < 0.01). In addition, the number of sites colonized with Candida spp. was a significant factor predicting response, with an estimated exposure odds ratio of 7.57 for those who were colonized at three or more sites compared with those colonized at one site (95% CI 1.20-47.70) (p = 0.031). In patients with Candida colonization, assessment of beta-D-glucan was useful for deciding whether to start empiric therapy for suspected candidiasis in surgical patients.

Antifungal drug resistance

The increasing incidence of invasive fungal infections is the result of many factors, including an increasing number of patients with severe immunosuppression. Although new drugs have been introduced to combat this problem, the development of resistance to antifungal drugs has become increasingly apparent, especially in patients who require long-term treatment or who are receiving antifungal prophylaxis, and there is growing awareness of shifts of flora to more-resistant species. The frequency, interpretation, and, in particular, mechanism of resistance to current classes of antifungal agents, particularly the azoles (where resistance has climbed most prominently) are discussed in this review.

Use of antifungal agents in febrile patients nonresponsive to antibacterial treatment: the current status in surgical and critical care patients in Japan

Disseminated candidiasis is difficult to diagnose and treat, and often becomes life-threatening in critically ill patients. However, guidelines or consensus views regarding the management of disseminated candidiasis do not exist in Japan. To develop feasible guidelines in Japan, we studied the current status of antifungal treatment in critically ill patients in Japan. From April 1999 to January 2000, critically ill patients from either surgical wards or critical care/intensive care units of 26 teaching hospitals were studied, using a prospective enrollment protocol. Patient enrollment criteria included persistent fever(> or =38 degrees C) for 3 days or more despite antibacterial agent administration. Data were entered at each institution and managed centrally using Clinware software. Of the 200 patients in the study, 68 (34%) received antifungal agents. Factors associated with antifungal treatment in the 68 patients included: central venous or pulmonary artery catheter, re-surgery, carbapenem or cephem administration, prolonged antibacterial agent administration, and high body temperature. Proven or probable disseminated candidiasis was presumed or diagnosed by culture in 34 patients, and by clinical signs and/or serological tests in 34 patients. Fungi isolated from blood included Candida albicans (57%), C. tropicalis (14%), C. parapsilosis (7%), C. glabrata (7%), and others (14%). Treatment patterns were as follows: 65 patients (96%) were treated with fluconazole (60 as monotherapy and 5 with amphotericin B); 2 patients, with miconazole; and 1 patient, with amphotericin B. Excluding 6 unevaluable cases, antifungal treatment was efficacious in 75% (21/28) of the patients with positive fungal culture and in 68% (23/34) of patients diagnosed by other means.

Clinical, cellular, and molecular factors that contribute to antifungal drug resistance

In the past decade, the frequency of diagnosed fungal infections has risen sharply due to several factors, including the increase in the number of immunosuppressed patients resulting from the AIDS epidemic and treatments during and after organ and bone marrow transplants. Linked with the increase in fungal infections is a recent increase in the frequency with which these infections are recalcitrant to standard antifungal therapy. This review summarizes the factors that contribute to antifungal drug resistance on three levels: (i) clinical factors that result in the inability to successfully treat refractory disease; (ii) cellular factors associated with a resistant fungal strain; and (iii) molecular factors that are ultimately responsible for the resistance phenotype in the cell. Many of the clinical factors that contribute to resistance are associated with the immune status of the patient, with the pharmacology of the drugs, or with the degree or type of fungal infection present. At a cellular level, antifungal drug resistance can be the result of replacement of a susceptible strain with a more resistant strain or species or the alteration of an endogenous strain (by mutation or gene expression) to a resistant phenotype. The molecular mechanisms of resistance that have been identified to date in Candida albicans include overexpression of two types of efflux pumps, overexpression or mutation of the target enzyme, and alteration of other enzymes in the same biosynthetic pathway as the target enzyme. Since the study of antifungal drug resistance is relatively new, other factors that may also contribute to resistance are discussed.