Pediatric Risk Factors for Candidemia Secondary to Candida glabrata and Candida krusei Species

Invasive candidiasis in children

The prevalence of invasive candidiasis (IC) in pediatric hospitals is from 4,3 to 15,2 per 10,000 hospitalized, in ICU – from 3,5 to 7 cases per 1,000, with HSCT – 2,9%. The average length of stay of a patient in the hospital before the development of IC varies from 21 to 56 days, in the ICU – more than 15 days. Knowledge of risk factors (ICU stay for ≥15 days, use of antibacterial drugs and parenteral nutrition, active malignant neoplasm, etc.) makes it possible to identify patients with a high (10-46%) risk of developing IC. Candida albicans remains the leading causative agent of IC in children, but infections with non-albicans Candida spp. have increased and an increase in the resistance of IC pathogens to azole antimycotics was noted. The main clinical variant of IC in children is candidemia, other forms include the central nervous system, abdominal organs, eyes, heart, bones and joints, kidneys, skin and subcutaneous tissue involvement, as well as chronic disseminated (hepatolienal) candidiasis. Blood culture, the main method of laboratory diagnostics of IC, is characterized by low sensitivity and requires a long time. Methods of noncultural diagnostics of IC (1,3-β-D-glucan, mannan and antimannan antibodies, T2 Candida etc) in children have not been sufficiently studied. The main drugs for the treatment of IC in children are echinocandins (anidulafungin, etc.), and CVC removal/replacement is necessary. The overall mortality rate in pediatric patients within 30 days after the diagnosis of IC is 37% to 44%.

Current Aspects in the Biology, Pathogeny, and Treatment of Candida krusei, a Neglected Fungal Pathogen

Fungal infections represent a constant and growing menace to human health, because of the emergence of new species as causative agents of diseases and the increment of antifungal drug resistance. Candidiasis is one of the most common fungal infections in humans and is associated with a high mortality rate when the fungi infect deep-seated organs. Candida krusei belongs to the group of candidiasis etiological agents, and although it is not isolated as frequently as other Candida species, the infections caused by this organism are of special relevance in the clinical setting because of its intrinsic resistance to fluconazole. Here, we offer a thorough revision of the current literature dealing with this organism and the caused disease, focusing on its biological aspects, the host-fungus interaction, the diagnosis, and the infection treatment. Of particular relevance, we provide the most recent genomic information, including the gene prediction of some putative virulence factors, like proteases, adhesins, regulators of biofilm formation and dimorphism. Moreover, C. krusei veterinary aspects and the exploration of natural products with anti-C. krusei activity are also included.

Invasive Candidiasis in Infants and Children: Recent Advances in Epidemiology, Diagnosis, and Treatment

This paper reviews recent advances in three selected areas of pediatric invasive candidiasis: epidemiology, diagnosis, and treatment. Although the epidemiological trends of pediatric invasive candidiasis illustrate a declining incidence, this infection still carries a heavy burden of mortality and morbidity that warrants a high index of clinical suspicion, the need for rapid diagnostic systems, and the early initiation of antifungal therapy. The development of non-culture-based technologies, such as the T2Candida system and (1→3)-β-d-glucan detection assay, offers the potential for early laboratory detection of candidemia and CNS candidiasis, respectively. Among the complications of disseminated candidiasis in infants and children, hematogenous disseminated Candida meningoencephalitis (HCME) is an important cause of neurological morbidity. Detection of (1→3)-β-d-glucan in cerebrospinal fluid serves as an early diagnostic indicator and an important biomarker of therapeutic response. The recently reported pharmacokinetic data of liposomal amphotericin B in children demonstrate dose–exposure relationships similar to those in adults. The recently completed randomized clinical trial of micafungin versus deoxycholate amphotericin B in the treatment of neonatal candidemia provides further safety data for an echinocandin in this clinical setting.

Candidemia in children: Epidemiology, prevention and management

Candidemia is the leading cause of invasive fungal infections in hospitalised children. The highest rates of candidemia have been recorded in neonates and infants <1 year of age. Candidemia is more frequent in neonates and young infants than in adults, and is associated with better clinical outcomes, but higher inpatient costs. Over the last 10 years, a declining trend has been noted in the incidence of paediatric candidemia in the US and elsewhere due to the hospital-wide implementation of central-line insertion and maintenance bundles that emphasise full sterile barrier precautions, chlorhexidine skin preparation during line insertion, meticulous site and tubing care, and daily discussion of catheter necessity. Additional interventions aiming at reducing gut-associated candidemia are required in immunocompromised and critically ill children.

Pediatric Invasive Candidiasis: Epidemiology and Diagnosis in Children

Pediatric patients present with differing underlying conditions and cytotoxic therapeutic protocols, so the differing epidemiology of invasive candidiasis in children versus adults is not surprising. Understanding the Candida species epidemiology is critical, as we often begin empiric therapy or therapy before antifungal susceptibilities are known. Reports with newer molecular diagnostic assays for invasive candidiasis are rare and require more study to develop firm pediatric-specific guidance. Antifungal treatment of pediatric candidiasis is reviewed in the context of larger epidemiologic studies and the few trials completed to date.

Multicenter evaluation of Candida QuickFISH BC for identification of Candida species directly from blood culture bottles

Candida species are common causes of bloodstream infections (BSI), with high mortality. Four species cause >90% of Candida BSI: C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis. Differentiation of Candida spp. is important because of differences in virulence and antimicrobial susceptibility. Candida QuickFISH BC, a multicolor, qualitative nucleic acid hybridization assay for the identification of C. albicans (green fluorescence), C. glabrata (red fluorescence), and C. parapsilosis (yellow fluorescence), was tested on Bactec and BacT/Alert blood culture bottles which signaled positive on automated blood culture devices and were positive for yeast by Gram stain at seven study sites. The results were compared to conventional identification. A total of 419 yeast-positive blood culture bottles were studied, consisting of 258 clinical samples (89 C. glabrata, 79 C. albicans, 23 C. parapsilosis, 18 C. tropicalis, and 49 other species) and 161 contrived samples inoculated with clinical isolates (40 C. glabrata, 46 C. albicans, 36 C. parapsilosis, 19 C. tropicalis, and 20 other species). A total of 415 samples contained a single fungal species, with C. glabrata (n = 129; 30.8%) being the most common isolate, followed by C. albicans (n = 125; 29.8%), C. parapsilosis (n = 59; 14.1%), C. tropicalis (n = 37; 8.8%), and C. krusei (n = 17; 4.1%). The overall agreement (with range for the three major Candida species) between the two methods was 99.3% (98.3 to 100%), with a sensitivity of 99.7% (98.3 to 100%) and a specificity of 98.0% (99.4 to 100%). This study showed that Candida QuickFISH BC is a rapid and accurate method for identifying C. albicans, C. glabrata, and C. parapsilosis, the three most common Candida species causing BSI, directly from blood culture bottles.