Candidemia in neonatal intensive care units: Barcelona, Spain

Neonatal candidiasis: epidemiology, risk factors, and clinical judgment

OBJECTIVE

Invasive candidiasis is a leading cause of infection-related morbidity and mortality in extremely low birth weight (<1000-g) infants. We quantified risk factors that predict infection in premature infants at high risk and compared clinical judgment with a prediction model of invasive candidiasis.

METHODS

The study involved a prospective observational cohort of infants≤1000 g birth weight at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. At each sepsis evaluation, clinical information was recorded, cultures were obtained, and clinicians prospectively recorded their estimate of the probability of invasive candidiasis. Two models were generated with invasive candidiasis as their outcome: (1) potentially modifiable risk factors; and (2) a clinical model at time of blood culture to predict candidiasis.

RESULTS

Invasive candidiasis occurred in 137 of 1515 (9.0%) infants and was documented by positive culture from ≥1 of these sources: blood (n=96); cerebrospinal fluid (n=9); urine obtained by catheterization (n=52); or other sterile body fluid (n=10). Mortality rate was not different for infants who had positive blood culture compared with those with isolated positive urine culture. Incidence of candida varied from 2% to 28% at the 13 centers that enrolled≥50 infants. Potentially modifiable risk factors included central catheter, broad-spectrum antibiotics (eg, third-generation cephalosporins), intravenous lipid emulsion, endotracheal tube, and antenatal antibiotics. The clinical prediction model had an area under the receiver operating characteristic curve of 0.79 and was superior to clinician judgment (0.70) in predicting subsequent invasive candidiasis.

CONCLUSION

Previous antibiotics, presence of a central catheter or endotracheal tube, and center were strongly associated with invasive candidiasis. Modeling was more accurate in predicting invasive candidiasis than clinical judgment.

Canadian clinical practice guidelines for invasive candidiasis in adults

Candidemia and invasive candidiasis (C/IC) are life-threatening opportunistic infections that add excess morbidity, mortality and cost to the management of patients with a range of potentially curable underlying conditions. The Association of Medical Microbiology and Infectious Disease Canada developed evidence-based guidelines for the approach to the diagnosis and management of these infections in the ever-increasing population of at-risk adult patients in the health care system. Over the past few years, a new and broader understanding of the epidemiology and pathogenesis of C/IC has emerged and has been coupled with the availability of new antifungal agents and defined strategies for targeting groups at risk including, but not limited to, acute leukemia patients, hematopoietic stem cell transplants and solid organ transplants, and critical care unit patients. Accordingly, these guidelines have focused on patients at risk for C/IC, and on approaches of prevention, early therapy for suspected but unproven infection, and targeted therapy for probable and proven infection.

[Epidemiology of invasive candidiasis in pediatric and adult populations]

BACKGROUND

Invasive candidiasis (IC) is the most frequent fungal disease in children and adults.

AIMS

To critically review and update the current epidemiology of Candida spp. disease in neonates, children and adults (critically ill patients and in oncohematologic patients and in solid organ transplant recipients).

METHODS

We searched the PubMed/Medline, discussing the current data.

RESULTS AND CONCLUSIONS

IC is associated with high attributable morbimortality and increased healthcare costs. In the last decades the incidence of invasive Candida spp. disease has increased in critically ill patients, has decreased in oncohematologic patients, although currently the involvement of non-albicans Candida species in the etiology of this disease is increasing steadily.

Antifungal agents in neonates: issues and recommendations

Fungal infections are responsible for considerable morbidity and mortality in the neonatal period, particularly among premature neonates. Four classes of antifungal agents are commonly used in the treatment of fungal infections in pediatric patients: polyene macrolides, fluorinated pyrimidines, triazoles, and echinocandins. Due to the paucity of pediatric data, many recommendations for the use of antifungal agents in this population are derived from the experience in adults. The purpose of this article was to review the published data on fungal infections and antifungal agents, with a focus on neonatal patients, and to provide an overview of the differences in antifungal pharmacology in neonates compared with adults. Pharmacokinetic data suggest dosing differences in children versus adult patients with some antifungals, but not all agents have been fully evaluated. The available pharmacokinetic data on the amphotericin B deoxycholate formulation in neonates exhibit considerable variability; nevertheless, the dosage regimen suggested in the neonatal population is similar to that used in adults. More pharmacokinetic information is available on the liposomal and lipid complex preparations of amphotericin B and fluconazole, and it supports their use in neonates; however, the optimal dosage and duration of therapy is difficult to establish. All amphotericin-B formulations, frequently used in combination with flucytosine, are useful for treating disseminated fungal infections and Candida meningitis in neonates. Fluconazole, with potent in vitro activity against Cryptococcus neoformans and almost all Candida spp., has been used in neonates with invasive candidiasis at dosages of 6 mg/kg/day, and for antifungal prophylaxis in high-risk neonates. There are limited data on itraconazole, voriconazole, and posaconazole use in neonates. Caspofungin, which is active against Candida spp. and Aspergillus spp., requires higher doses in children relative to adults, and dosing is best accomplished based on body surface area. Micafungin shows a clear trend toward lower levels in the smallest patients. There are no data on the use of other new antifungal drugs (ravuconazole and anidulafungin) in neonates. In summary, the initial data suggest dosage differences in neonates for some antifungal agents, although the newer agents have not been fully tested for optimal administration in these patients.

[In vitro antifungal activity of voriconazole: New data after the first years of clinical experience]

Voriconazole has been developed to meet the increasing need for new and useful antifungal agents for the treatment of invasive mycoses. This review describes the spectrum of voriconazole antifungal activity based on data from in vitro studies published during the last three years. This survey demonstrates that voriconazole has a broad antifungal spectrum against the most common fungal pathogens being its action fungistatic for Candida and fungicidal for Aspergillus and other filamentous fungi. Overall, more than 95% of all Candida isolates tested are susceptible to voriconazole and less than 3% are resistant. Similar or even better activity rates have been described for Aspergillus, Cryptococcus and most of yeasts and moulds of medical importance. We also discuss the limitations related to the azole cross-resistance observed in some Candida glabrata isolates, the poor activity of voriconazole against Scedosporium prolificans, its activity against fungal biofilms and the great potential usefulness of combination of voriconazole with other antifungal drugs.

Candidemia and candiduria in critically ill patients admitted to intensive care units in France: incidence, molecular diversity, management and outcome

OBJECTIVE

To determine the concomitant incidence, molecular diversity, management and outcome of nosocomial candidemia and candiduria in intensive care unit (ICU) patients in France.

DESIGN

A 1-year prospective observational study in 24 adult ICUs.

PATIENTS

Two hundred and sixty-two patients with nosocomial candidemia and/or candiduria.

MEASUREMENTS AND RESULTS

Blood and urine samples were collected when signs of sepsis were present. Antifungal susceptibility of Candida strains was determined; in addition, all blood and 72% of urine C. albicans isolates were analyzed by using multi-locus sequence type (MLST). The mean incidences of candidemia and candiduria were 6.7 and 27.4/1000 admissions, respectively. Eight percent of candiduric patients developed candidemia with the same species. The mean interval between ICU admission and candidemia was 19.0 +/- 2.9 days, and 17.2 +/- 1.1 days for candiduria. C. albicans and C. glabrata were isolated in 54.2% and 17% of blood and 66.5% and 21.6% of urine Candida-positive cultures, respectively. Fluconazole was the most frequently prescribed agent. In all candidemic patients, the prescribed curative antifungal agent was active in vitro against the responsible identified strain. Crude ICU mortality was 61.8% for candidemic and 31.3% for candiduric patients. Seventy-five percent of the patients were infected with a unique C. albicans strain; cross-transmission between seven patients was suggested in one hospital.

CONCLUSIONS

Candidemia is late-onset ICU-acquired infection associated with high mortality. No difference in susceptibility and genetic background were found between blood and urine strains of Candida species.

A comparison of AmBisome to amphotericin B for treatment of systemic candidiasis in very low birth weight infants

PURPOSE

Amphotericin B is considered the treatment of choice for systemic candidiasis, but adverse effects may limit its use. An alternative option for the treatment of candidiasis includes lipid preparations of amphotericin B. This study investigated the safety and efficacy of AmBisome, a lipid formulation of amphotericin B containing liposomal structures, for the treatment of systemic candidiasis in very low birth weight infants (VLBWI).

MATERIALS AND METHODS

Data from 26 VLBWI treated with AmBisome in the study group (AmBisome group) from October 2003 to July 2006 were compared with data from 20 VLBWI treated with amphotericin B as a historical control (Amphotericin group). This study was a prospective, historical control, multi-center trial.

RESULTS

Candida spp. was isolated in 73% (19/26) of the cases for the AmBisome group and 90% (18/20) of the cases for the Amphotericin group. The fungal eradication rate and the time to eradication was 84% (16/19) and 9+/-8 days in the AmBisome group, and 89% (16/18) and 10+/-9 days in the Amphotericin group, respectively (p=0.680 vs p=0.712). The major adverse effects were lower in the AmBisome group (renal toxicity, 21% vs 55%, p=0.029; hepatotoxity, 25% vs 65%, p=0.014, AmBisome group vs Amphotericin group, respectively). There was no significant difference in mortality attributed to systemic candidiasis (12% in the AmBisome group, 10% in the Amphotericin group, p=0.868).

CONCLUSION

AmBisome is effective and safe for treating systemic fungal infections in VLBWI.

Occurrence and genetic variability of Candida parapsilosis sensu lato in Hungary

The occurrence and genetic variability of Candida parapsilosis isolates in two Hungarian hospitals, located in Debrecen and Pécs, were examined. Among the 209 Candida isolates examined, 20 were found to belong to C. parapsilosis sensu lato, based on morphological, physiological and molecular data. The frequency of occurrence of C. parapsilosis isolates (9.6%) was lower than that observed in Europe but higher than that observed previously in Hungary. The genetic variability of C. parapsilosis sensu lato isolates was also examined using random amplified polymorphic DNA (RAPD) analysis and sequence analysis of the intergenic transcribed spacer (ITS) region of the rRNA gene cluster. The genetic variability of the isolates was relatively high, as revealed by RAPD analysis. Two isolates were found to belong to the recently described Candida metapsilosis species (C. parapsilosis group III), based on ITS sequence data, RAPD analysis and phenotypic data. These two isolates could also be distinguished from C. parapsilosis sensu stricto isolates using a primer pair developed for the detection of C. parapsilosis group I isolates. To the best of the authors' knowledge, this is the first report on the identification of C. metapsilosis from bloodstream infection.

Healthcare-associated infections in neonatal units: lessons from contrasting worlds

Neonatal intensive care units are vulnerable to outbreaks and sporadic incidents of healthcare-associated infections (HAIs). The incidence and outcome of these infections are determined by the degree of immaturity of the neonatal immune system, invasive procedures involved, the aetiological agent and its antimicrobial susceptibility pattern and, above all, infection control policies practised by the unit. It is important to raise awareness of infection control practices in resource-limited settings, since overdependence upon antimicrobial agents and co-existing lack of awareness of infection control is encouraging the emergence of multi-drug-resistant nosocomial pathogens. We reviewed 125 articles regarding HAIs from both advanced and resource-limited neonatal units in order to study risk factors, aetiological agents, antimicrobial susceptibility patterns and reported successes in infection control interventions. The articles include surveillance studies, outbreaks and sporadic incidents. Gram-positive cocci, viruses and fungi predominate in reports from the advanced units, while Gram-negative enteric rods, non-fermenters and fungi are commonly reported from resource-limited settings. Antimicrobial susceptibility patterns from surveillance studies determined the empirical therapy used in each neonatal unit. Most outbreaks, irrespective of the technical facilities available, were traced to specific lack of infection control practices. We discuss infection control interventions, with special emphasis on their applicability in resource-limited settings. Cost-effective measures for implementing these interventions, with particular reference to the recognition of the role of the microbiologist, the infection control team and antibiotic policies are presented.

Epidemiology, risk factors, and prognosis of Candida parapsilosis bloodstream infections: case-control population-based surveillance study of patients in Barcelona, Spain, from 2002 to 2003

Candida parapsilosis has emerged as an important yeast species causing fungemia. We describe the incidence and epidemiology of C. parapsilosis fungemia. Data from active population-based surveillance in Barcelona, Spain, from January 2002 to December 2003 were analyzed. We focused on 78 episodes of C. parapsilosis fungemia, and we compared them with 175 Candida albicans controls. C. parapsilosis accounted for 23% of all fungemias. The annual incidences were 1 episode per 10(5) patients, 1.2 episodes per 10(4) discharges, and 1.7 episodes per 10(5) patient days. All isolates but one (99%) were fluconazole susceptible. Seventy-two isolates (92%) were inpatient candidemias. Forty-two episodes (51%) were considered catheter-related fungemia, 35 (45%) were considered primary fungemia, and 3 (4%) were considered secondary fungemia. Risk factors for candidemia were vascular catheterization (97%), prior antibiotic therapy (91%), parenteral nutrition (54%), prior surgery (46%), prior immunosuppressive therapy (38%), malignancy (27%), prior antifungal infection (26%), transplant recipient (16%), neutropenia (12%), and prior colonization (11%). Multivariate analysis of the differential characteristics showed that the factors that independently predicted the presence of C. parapsilosis fungemia were neonate patients (odds ratio [OR], 7.5; 95% confidence interval [CI], 2.1 to 26.8; P = 0.002), transplant recipients (OR, 9.2; 95% CI, 1.9 to 43.3; P = 0.005), patients with a history of prior antifungal therapy (OR, 5.4; 95% CI, 1.8 to 15.9; P = 0.002), and patients who received parenteral nutrition (OR, 2.2; 95% CI, 1.09 to 4.6; P = 0.028). The overall mortality rate was lower than that associated with C. albicans candidemia (23% versus 43%; P < 0.01). In summary, C. parapsilosis was responsible for 23% of all candidemias and was more frequent in neonates, in transplant recipients, and in patients who received parenteral nutrition or previous antifungal therapy, mainly fluconazole. The mortality rate was lower than that associated with C. albicans fungemia.