Candidemia in Finland, 1995-1999

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.

Treatment of candidemia and invasive candidiasis in the intensive care unit: post hoc analysis of a randomized, controlled trial comparing micafungin and liposomal amphotericin B

Introduction

Invasive candidiasis and candidemia are life-threatening nosocomial infections in intensive care patients.

Methods

A post hoc analysis of a phase 3 trial assessing micafungin (100 mg/day for subjects > 40 kg; 2 mg/kg/day for subjects ≤ 40 kg) versus liposomal amphotericin B (3 mg/kg/day). Subgroups were defined according to the type of ward on the first day of treatment: intensive care unit (ICU) or non-ICU. Multivariate regression was performed to identify factors associated with treatment success at end of therapy and all-cause mortality at days 8 and 30.

Results

In non-ICU subjects, treatment success was significantly higher for micafungin versus liposomal amphotericin B (85% (n = 108/127) versus 72.1% (n = 98/136); P = 0.0113). However, for ICU subjects, treatment success rates for micafungin versus liposomal amphotericin B were similar (62.5% (n = 75/120) versus 66.4% (n = 73/110); P = 0.5828). Overall, treatment success was significantly lower in ICU subjects compared with non-ICU subjects (64.3% (n = 148/230) versus 78.3% (n = 206/263); P = 0.0006). Multivariate regression analysis revealed a lower likelihood of treatment success for: ICU versus non-ICU subjects; persistent neutropenia; and high versus low Acute Physiology and Chronic Health Evaluation (APACHE) II scores. However, when interactions between potential explanatory factors were included in the analysis model, ICU status no longer emerged as a significant associated variable but the association between APACHE II score and treatment outcome remained. Further analyses indicated that the likelihood of mortality at day 8 and day 30 was lower for subjects with lower APACHE II scores. Renal function was significantly better in micafungin versus liposomal amphotericin B subjects: a difference (liposomal amphotericin B - micafungin in mean peak change in estimated glomerular filtration rate (ml/minute/1.73 m²) of -18.2 (P < 0.0001) and -17.7 (P = 0.0124) in non-ICU and ICU subjects, respectively.

Conclusions

Overall, ICU subjects had lower treatment success rates than non-ICU subjects for both liposomal amphotericin B and micafungin. Multivariate regression after controlling for potential confounding factors suggested the APACHE II score remained a potential explanatory factor associated with treatment success, mortality at day 8, and mortality at day 30.

Trial registration

Post hoc analysis - clinicaltrials.gov trial NCT00106288.

Invasive candidiasis and candidemia: from current opinions to future perspectives

Candida spp. are the fourth most common cause of nosocomial bloodstream infections in the United States, as well as the single most important cause of opportunistic fungal infections worldwide. A delayed diagnosis of invasive candidiasis and/or inadequate treatment choice is associated with high mortality rates and prolonged hospital stays. Even though the antifungal armamentarium has been broadened significantly over the last years, the best options for diagnosing and treating invasive candidiasis still remain a matter of discussion. In this article we present and analyze current evidence on the epidemiology, diagnostic methods and treatment options of invasive candidiasis, with a focus on results from randomized clinical trials. Finally, the reader is provided with a brief overview on promising clinical trial designs and antifungals that might shape the treatment of invasive candidiasis in the years to come.

Candidaemia with uncommon Candida species: predisposing factors, outcome, antifungal susceptibility, and implications for management

The risk factors for and clinical features of bloodstream infection with uncommon Candida spp. (species other than C. albicans, C. glabrata, C. parapsilosis, C. tropicals and C. krusei) are incompletely defined. To identify clinical variables associated with these species that might guide management, 57 cases of candidaemia resulting from uncommon Candida spp. were analysed in comparison with 517 episodes of Candida albicans candidaemia (2001-2004). Infection with uncommon Candida spp. (5.3% of candidaemia cases), as compared with C. albicans candidaemia, was significantly more likely to be outpatient-acquired than inpatient-acquired (15 of 57 vs. 65 of 517 episodes, p 0.01). Prior exposure to fluconazole was uncommon (n=1). Candida dubliniensis was the commonest species (n=22, 39%), followed by Candida guilliermondii (n=11, 19%) and Candida lusitaniae (n=7, 12%).C. dubliniensis candidaemia was independently associated with recent intravenous drug use (p 0.01) and chronic liver disease (p 0.03), and infection with species other than C. dubliniensis was independently associated with age<65 years (p 0.02), male sex (p 0.03) and human immunodeficiency virus infection (p 0.05). Presence of sepsis at diagnosis and crude 30-day mortality rates were similar for C. dubliniensis-related, non-C. dubliniensis-related and C. albicans-related candidaemia. Haematological malignancy was the commonest predisposing factor in C. guilliermondii (n=3, 27%) and C. lusitaniae (n=3, 43%) candidaemia. The 30-day mortality rate of C. lusitaniae candidaemia was higher than the overall death rate for all uncommon Candida spp. (42.9% vs. 25%, p not significant). All isolates were susceptible to amphotericin B, voriconazole, posaconazole, and caspofungin; five strains (9%) had fluconazole MIC values of 16-32 mg/L. Candidaemia due to uncommon Candida spp. is emerging among hospital outpatients; certain clinical variables may assist in recognition of this entity.

Improving survival of patients with candidaemia: Analysis of prognostic factors from a long-term, nationwide study in Iceland

A population-based epidemiological and clinical study of candidaemia in Iceland was conducted during a 20-y period, 1980-1999. As previously reported, the incidence of candidaemia increased 3.5-fold during the study period, without major changes in species distribution or antifungal resistance (Asmundsdottir et al., J Clin Microbiol 2002;40:3489-92). In this study detailed clinical information was collected and registered on all candidaemic patients (n=165, episodes n=172) in Iceland during 1980-1999. Clinical characteristics were compared between adults and children. Univariate and multivariate analyses were used to determine predictors of 30-d mortality. In comparison with adults, young children with candidaemia more often presented with respiratory distress, without fever p<0.001. Adult patients were more likely to have underlying malignancies (p=0.009) and to have undergone surgical operations (p=0.002). During the study a steady decrease in 30-d case fatality ratio was noted, from 58.8% in 1980-1984, to 26.7% in 1995-1999 (p=0.02). At the same time a more aggressive approach to candidaemia management was documented. In multivariate analysis, prompt removal of central venous catheters (odds ratio for death, 0.22, p=0.004), and septic shock (odds ratio for death, 8.01, p=0.001) were the strongest independent predictors of outcome. Our results underline the strong association between prompt removal of vascular catheters and favourable outcome, suggesting that mortality may be reduced by more aggressive management.

The changing face of epidemiology of invasive fungal disease in Europe

Invasive fungal diseases (IFDs) are an increasingly common complication in critically ill patients in Europe and are frequently fatal. Because of changes in treatment strategies and the increased use of antifungal prophylaxis, the epidemiology of IFDs has changed substantially in recent years and infections due to Candida species are no longer the majority in many institutions. In contrast, the emergence of non-Candida IFDs such as aspergillosis, zygomycosis and fusariosis has increased. European surveys indicate that Candida albicans is responsible for more than half the cases of invasive candidaemia; however, the occurrence of non-albicans-related IFDs appears to be increasing. Rates of IFD-related mortality in Europe depend on the pathogen, geographical location and underlying patient characteristics, with rates ranging from 28 to 59% for Candida infections and from 38 to 80% for invasive aspergillosis. Early initiation of antifungal therapy is critical for improving outcomes; however, this is complicated by the difficulty in diagnosing IFDs rapidly and accurately. The introduction of new extended-spectrum azole antifungal agents (e.g. voriconazole, posaconazole) and echinocandins (e.g. micafungin, caspofungin, anidulafungin) has increased the number of therapeutic options for early therapy. Choice between agents should be based on a variety of factors, including spectrum of activity, adverse events, drug interactions, route of administration, clinical efficacy of individual agents and local epidemiology.

Not just little adults: candidemia epidemiology, molecular characterization, and antifungal susceptibility in neonatal and pediatric patients

OBJECTIVE

The purpose of this work was to identify differences in incidence, risk factors, microbiology, treatment, and clinical outcome of candidemia in neonates, children, and adults that might impact on management.

PATIENTS AND METHODS

Cases of candidemia in Australia were identified prospectively by blood culture surveillance over 3 years. Episodes of candidemia in neonatal, pediatric, and adult age groups were analyzed and compared.

RESULTS

Of 1005 incident cases, 33 occurred in neonates, 110 in children, and 862 in adults. The respective annual age-specific incidences were 4.4, 0.9, and 1.8 per 100,000 population. Prematurity and ICU admission were major risk factors in neonates. Hematologic malignancy and neutropenia were significantly more frequent in children than in neonates and adults. Diabetes, renal disease, hemodialysis, and recent surgery were more common in adults. Candidemia was attributed to a vascular access device in 58% of neonates, 70% of children, and 44% of adults. Candida albicans caused approximately 48% of cases in all of the age groups. Candida parapsilosis was significantly more common in neonates and children (42% and 38% vs 15%). Candida glabrata was infrequent in neonates and children (9% and 3% vs 17%). Significantly more isolates from children were susceptible to fluconazole compared with those from adults (95% vs 75%). Fluconazole-resistant candidal isolates were infrequent in all of the age groups. Neonates and children were more likely to receive amphotericin B compared with adults. Adults were more likely to receive fluconazole. Survival rates at 30 days were 78% in neonates, 90% in children, and 70% in adults.

CONCLUSIONS

This study identifies significant differences in candidemia in neonates, children, and adults. Neonatologists and pediatricians must consider age-specific differences when interpreting adult studies and developing treatment and prevention guidelines.

Candidemia in the 21st century

The 21st century has brought forth vast innovations in the healthcare field. The availability and use of aggressive chemotherapeutic and immunosuppressive agents as well as broad-spectrum antibacterial agents has created a large population of patients who are at increased risk of acquiring infections with fungal organisms, especially Candida species. This review will focus on the changing epidemiology of candidal bloodstream infections, its impact on healthcare and new advances in the diagnosis and treatment of candidemia.

New options for treatment of candidaemia in critically ill patients

Bloodstream infections caused by Candida spp. are increasingly recognised in critically ill adult and paediatric individuals, with significant associated morbidity and mortality. Candida albicans is the single most common fungal species to cause nosocomial infections. However, non-C. albicans spp., including Candida glabrata and Candida krusei, which are less susceptible to fluconazole, have become more common. Until the 1980s, the therapeutic possibilities for invasive candidosis were limited to amphotericin B, but with the advent of new antifungal agents, such as azoles and echinocandins, less toxic therapeutic options have become available and there are now possibilities for prevention and optimised therapy for documented Candida infections. In this review, the currently available options for the treatment of candidaemia and invasive candidosis are discussed with regard to the role of liposomal amphotericin B in comparison with the echinocandins and azoles.

Fungemia in non-HIV-infected patients: a five-year review

OBJECTIVES

To investigate the incidence, risk factors, causative fungi, and outcomes of fungemia in adult, non-HIV-infected patients.

DESIGN

We studied 147 episodes of fungemia due to Candida spp and Trichosporon spp in adult patients admitted to a university hospital in Northeast Thailand between 1999 and 2003.

RESULTS

The overall incidence of fungemia was 14.1 per 10,000 hospital admissions. Candida was the most common isolate (138 episodes, 93.9%) with non-albicans Candida accounting for 68.7%. The major non-albicans Candida isolates were Candida parapsilosis and Candida tropicalis. Fungemia caused by Trichosporon accounted for 6.1% of the cases, but their clinical features could not be distinguished from fungemia due to Candida. The overall in-hospital mortality rate was 56.1%. The independent factors related to mortality were high APACHE II score (odds ratio (OR) 1.12 per 1-point increments, 95% confidence interval (CI) 1.03-1.23), assisted ventilation (OR 3.49, 95% CI 1.04-11.64), and neutropenia (OR 7.47, 95% CI 1.25-44.74).

CONCLUSIONS

Candidemia, especially that caused by non-albicans Candida, was an important nosocomial infection in this tertiary care hospital in Northeast Thailand. The mortality rate was high, particularly in patients who were critically ill. Rapid diagnosis and early treatment are therefore important challenges for improving clinical outcomes.

Semi-national surveillance of fungaemia in Denmark 2004-2006: increasing incidence of fungaemia and numbers of isolates with reduced azole susceptibility

A semi-national laboratory-based surveillance programme for fungaemia was initiated in 2003 that now covers c. 3.5 million inhabitants (64%) of the Danish population. In total, 1089 episodes of fungaemia were recorded during 2004-2006, corresponding to an annual incidence of 10.4/100 000 inhabitants. The annual number of episodes increased by 17% during the study period. Candida spp. accounted for 98% of the fungal pathogens. Although Candida albicans remained predominant, the proportion of C. albicans decreased from 66.1% in 2004 to 53.8% in 2006 (p <0.01), and varied considerably among participating departments, e.g., from 51.1% at a university hospital in Copenhagen to 67.6% in North Jutland County. Candida glabrata ranked second, and increased in proportion from 16.7% to 22.7% (p 0.04). Candida krusei was isolated rarely (4.1%), but the proportion doubled during the study period from 3.2% to 6.4% (p 0.06). MIC distributions of amphotericin B and caspofungin were in close agreement with the patterns predicted by species identification; however, decreased susceptibility to voriconazole, defined as an MIC of >1 mg/L, was detected in one (2.5%) C. glabrata isolate in 2004 and in 12 (14.0%) isolates in 2006 (p 0.03). Overall, the proportion of isolates with decreased susceptibility to fluconazole exceeded 30% in 2006. The incidence of fungaemia in Denmark was three-fold higher than that reported from other Nordic countries and is increasing. Decreased susceptibility to fluconazole is frequent, and a new trend towards C. glabrata isolates with elevated voriconazole MICs was observed.

Increase in bloodstream infections in Finland, 1995-2002

A national, population-based laboratory surveillance of bloodstream infections (BSI) in Finland was performed. Blood-culturing rates were determined from data from clinical microbiology laboratories and trends in rates were evaluated using Poisson regression. During 1995-2002, 51,510 cases of BSI were notified; the annual incidence increased from 104 to 145 cases/100,000 (40%). Rates increased in all age groups but persons aged >or= 75 years accounted for 28% of cases and showed the largest rate increase. Escherichia coli, coagulase-negative staphylococci, Staphylococcus aureus and Streptococcus pneumoniae accounted for 58% of isolates and their relative proportions were unchanged over time. The annual blood-culturing rate increased by one-third during the study period but the number of BSI detected per blood cultures remained unchanged. Regional BSI incidence was significantly associated with blood-culturing rates. We conclude that the increase in BSI rates may have been due to more frequent blood culturing but was not associated with changes in the reporting system or aetiology of BSI.

One year prospective survey of Candida bloodstream infections in Scotland

A 12 month survey of candidaemia in Scotland, UK, in which every Scottish hospital laboratory submitted all blood isolates of yeasts for identification, strain typing and susceptibility testing, provided 300 isolates from 242 patients, generating incidence data of 4.8 cases per 100,000 population per year and 5.9 cases per 100,000 acute occupied bed days; 27.9 % of cases occurred in intensive care units. More than half the patients with candidaemia had an underlying disease involving the abdomen, 78 % had an indwelling intravenous catheter, 62 % had suffered a bacterial infection within the 2 weeks prior to candidaemia and 37 % had undergone a laparotomy. Candida albicans was the infecting species in 50 % of cases, followed by Candida glabrata (21 %) and Candida parapsilosis (12 %). Seven cases of candidaemia were caused by Candida dubliniensis, which was more prevalent even than Candida lusitaniae and Candida tropicalis (six cases each). Among C. glabrata isolates, 55 % showed reduced susceptibility to fluconazole, but azole resistance among other species was extremely low. Multilocus sequence typing showed isolates with high similarity came from different hospitals across the country, and many different types came from the hospitals that submitted the most isolates, indicating no tendency towards hospital-specific endemic strains. Multiple isolates of C. albicans and C. glabrata from individual patients were of the same strain type with single exceptions for each species. The high prevalence of candidaemia in Scotland, relative to other population-based European studies, and the high level of reduced fluconazole susceptibility of Scottish C. glabrata isolates warrant continued future surveillance of invasive Candida infections.

A cluster of Candida krusei infections in a haematological unit

BACKGROUND

Candida krusei infections are associated with high mortality. In order to explore ways to prevent these infections, we investigated potential routes for nosocomial spread and possible clonality of C. krusei in a haematological unit which had experienced an unusually high incidence of cases.

METHODS

We searched for C. krusei contamination of the hospital environment and determined the level of colonization in patients and health care workers. We also analyzed the possible association between exposure to prophylactic antifungals or chemotherapeutic agents and occurrence of C. krusei. The C. krusei isolates found were genotyped by pulsed-field electrophoresis method in order to determine possible relatedness of the cases.

RESULTS

Twelve patients with invasive C. krusei infection and ten patients with potentially significant infection or mucosal colonization were documented within nine months. We were unable to identify any exogenic source of infection or colonization. Genetic analysis of the isolates showed little evidence of clonal transmission of C. krusei strains between the patients. Instead, each patient was colonized or infected by several different closely related genotypes. No association between medications and occurrence of C. krusei was found.

CONCLUSION

Little evidence of nosocomial spread of a single C. krusei clone was found. The outbreak may have been controlled by cessation of prophylactic antifungals and by intensifying infection control measures, e.g. hand hygiene and cohorting of the patients, although no clear association with these factors was demonstrated.

A retrospective nationwide case study on the use of a new antifungal agent: patients treated with caspofungin during 2001–2004 in Finland

The aim of this study was to evaluate the efficacy and safety of caspofungin in patients treated in Finland during the period 2001-2004. The medical records of 78 adult patients treated with caspofungin in five major hospitals were reviewed retrospectively. Fifty-nine (76%) patients had proven invasive fungal infection, of whom 22 (28%) had aspergillosis and 37 (47%) had candidiasis. Nineteen (24%) patients were treated empirically; only 13 (17%) patients received caspofungin as primary therapy. A favourable response was achieved in 52 (67%) patients. The response rate was 78% in patients with candidiasis, and 50% in patients with aspergillosis. At the end of the study period, 40 (51%) patients remained alive; of the 38 deaths, nine (24%) were caused by fungal infection. The response rates were lower, although not significantly, for patients with high (>20) vs. low (< or =20) Acute Physiology and Chronic Health Evaluation (APACHE II) scores (response rate 50% vs. 68%, p 0.48, respectively), and were also lower in patients with long-term (>20 days) vs. shorter duration (< or =20 days) neutropenia (55% vs. 73%, p 0.32, respectively), and in those with an underlying haematological malignancy vs. patients with other diseases (59% vs. 73%, p 0.2, respectively). In five (6%) patients, caspofungin therapy was discontinued prematurely because of adverse drug reactions (ADRs) (elevated liver enzyme values in three patients, neuropathic pain in one, and skin rash in one). Serious ADRs occurred in two (3%) patients (severe hepatic insufficiency with consequent death, and eosinophilia with elevated alkaline phosphatase levels), and laboratory abnormalities, mostly mild and reversible, in 24 (31%) patients. In this unselected patient population, caspofungin was safe, well-tolerated, and had an efficacy comparable to that in previous reports from prospective trials.

Candidemia due to Candida tropicalis: clinical, epidemiologic, and microbiologic characteristics of 188 episodes occurring in tertiary care hospitals

Candida tropicalis is the 2nd most frequent agent of candidemia in Brazil (20-24%). We attempted to characterize the epidemiology, microbiology, and outcome of candidemia due to C. tropicalis by comparing patients with candidemia due to C. tropicalis with those with candidemia due to Candida albicans. Among the 924 episodes of candidemia, 188 (20%) were caused by C. tropicalis. These cases were compared with 384 candidemias due to C. albicans. C. tropicalis was the 2nd most frequent species in adults (21.6%) and elderly patients (23.2%), and 3rd in neonates (11.9%) and children (18.5%). Cancer was the most frequent underlying disease, and in adults and elderly patients, diabetes was the 2nd most frequent underlying disease. The only difference between C. tropicalis and C. albicans candidemia was a higher proportion of neutropenic patients in C. tropicalis candidemia. C. tropicalis is a leading cause of candidemia in Brazil, and its epidemiology is similar to that of C. albicans.

Epidemiology of invasive candidiasis: a persistent public health problem

Invasive candidiasis (IC) is a leading cause of mycosis-associated mortality in the United States. We examined data from the National Center for Health Statistics and reviewed recent literature in order to update the epidemiology of IC. IC-associated mortality has remained stable, at approximately 0.4 deaths per 100,000 population, since 1997, while mortality associated with invasive aspergillosis has continued to decline. Candida albicans remains the predominant cause of IC, accounting for over half of all cases, but Candida glabrata has emerged as the second most common cause of IC in the United States, and several less common Candida species may be emerging, some of which can exhibit resistance to triazoles and/or amphotericin B. Crude and attributable rates of mortality due to IC remain unacceptably high and unchanged for the past 2 decades. Nonpharmacologic preventive strategies should be emphasized, including hand hygiene; appropriate use, placement, and care of central venous catheters; and prudent use of antimicrobial therapy. Given that delays in appropriate antifungal therapy are associated with increased mortality, improved use of early empirical, preemptive, and prophylactic therapies should also help reduce IC-associated mortality. Several studies have now identified important variables that can be used to predict risk of IC and to help guide preventive strategies such as antifungal prophylaxis and early empirical therapy. However, improved non-culture-based diagnostics are needed to expand the potential for preemptive (or early directed) therapy. Further research to improve diagnostic, preventive, and therapeutic strategies is necessary to reduce the considerable morbidity and mortality associated with IC.

Active surveillance for candidemia, Australia

This infection has a high death rate and is predominantly associated with healthcare.

Population-based surveillance for candidemia in Australia from 2001 to 2004 identified 1,095 cases. Annual overall and hospital-specific incidences were 1.81/100,000 and 0.21/1,000 separations (completed admissions), respectively. Predisposing factors included malignancy (32.1%), indwelling vascular catheters (72.6%), use of antimicrobial agents (77%), and surgery (37.1%). Of 919 episodes, 81.5% were inpatient healthcare associated (IHCA), 11.6% were outpatient healthcare associated (OHCA), and 6.9% were community acquired (CA). Concomitant illnesses and risk factors were similar in IHCA and OHCA candidemia. IHCA candidemia was associated with sepsis at diagnosis (p<0.001), death <30 days after infection (p<0.001), and prolonged hospital admission (p<0.001). Non–Candida albicans species (52.7%) caused 60.5% of cases acquired outside hospitals and 49.9% of IHCA candidemia (p = 0.02). The 30-day death rate was 27.7% in those >65 years of age. Adult critical care stay, sepsis syndrome, and corticosteroid therapy were associated with the greatest risk for death. Systematic epidemiologic studies that use standardized definitions for IHCA, OHCA, and CA candidemia are indicated.

Trends in the Epidemiology of Invasive Fungal Infections

Invasive fungal infections have increased in importance, largely because of the increasing size of the population at risk. Candida species remain the fourth most important cause of hospital-acquired bloodstream infections. Infections with Candida species other than C. albicans appear to have become more common, but significant geographic variation has been reported. Invasive aspergillosis and other mould infections are a leading cause of infection-related death in hematopoietic stem cell transplant recipients. Although Aspergillus fumigatus remains the most frequent cause of infection, A. terreus has emerged as an important pathogen, at least among certain populations. Despite marked reductions in the rates of AIDS-associated fungal infections, such as cryptococcosis, in the United States and other developed countries, the burden of these diseases in developing countries is large and increasing. Enhanced surveillance and reporting will be critical to improve our understanding of the importance of invasive fungal infections, to enable prioritization of research and prevention efforts, and to evaluate prevention strategies.

Epidemiology of candidemia in Brazil: a nationwide sentinel surveillance of candidemia in eleven medical centers

Candidemia studies have documented geographic differences in rates and epidemiology, underscoring the need for surveillance to monitor trends. We conducted prospective candidemia surveillance in Brazil to assess the incidence, species distribution, frequency of antifungal resistance, and risk factors for fluconazole-resistant Candida species. Prospective laboratory-based surveillance was conducted from March 2003 to December 2004 in 11 medical centers located in 9 major Brazilian cities. A case of candidemia was defined as the isolation of Candida spp. from a blood culture. Incidence rates were calculated per 1,000 admissions and 1,000 patient-days. Antifungal susceptibility tests were performed by using the broth microdilution assay, according to the Clinical and Laboratory Standards Institute guidelines. We detected 712 cases, for an overall incidence of 2.49 cases per 1,000 admissions and 0.37 cases per 1,000 patient-days. The 30-day crude mortality was 54%. C. albicans was the most common species (40.9%), followed by C. tropicalis (20.9%) and C. parapsilosis (20.5%). Overall, decreased susceptibility to fluconazole occurred in 33 (5%) of incident isolates, 6 (1%) of which were resistant. There was a linear correlation between fluconazole and voriconazole MICs (r = 0.54 and P < 0.001 [Spearman's rho]). This is the largest multicenter candidemia study conducted in Latin America and shows the substantial morbidity and mortality of candidemia in Brazil. Antifungal resistance was rare, but correlation between fluconazole and voriconazole MICs suggests cross-resistance may occur.

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.

Candida guilliermondii fungemia in patients with hematologic malignancies

The microbiological, clinical, and epidemiological features of most non-Candida albicans Candida species are well known, but much less is known about species such as Candida guilliermondii, an uncommon pathogen causing a variety of deep-seated infections in immunocompromised hosts. To characterize C. guilliermondii fungemia in patients with hematological malignancies and its susceptibility to antifungal drugs, all cases of C. guilliermondii fungemia diagnosed in our department between 1983 and 2005 were retrospectively analyzed and the literature was reviewed. C. guilliermondii caused 29/243 (11.7%) candidemia episodes diagnosed during the study period. Central venous catheters were the documented sources of candidemia in 19/29 episodes (65.5%), and invasive tissue infections were documented in 2 (6.9%). In the remaining eight, the catheter was not removed and the source of the fungemia remained obscure. Seven episodes ended in death, but only one could be attributed to invasive C. guilliermondii infection. Molecular typing data reveal no evidence of common infection sources. Isolates displayed high rates of in vitro susceptibility to amphotericin B (100%), voriconazole (95%), and fluconazole (90%) and lower rates of in vitro susceptibility to flucytosine (86%), itraconazole (76%), and caspofungin (33%). Our literature review confirms that C. guilliermondii is a significantly more frequent cause of candidemia among cancer patients compared with the general hospital population. It accounted for <1% of the total number of Candida bloodstream isolates reported in the articles we reviewed, with higher rates in Europe (1.4%) and Asia (1.8%) compared with North America (0.3%).

Candidemia in Norway (1991 to 2003): results from a nationwide study

A long-term, nationwide prospective candidemia study has been ongoing in Norway since 1991. All medical microbiological laboratories in the country have participated. During the period 1991 to 2003 a total of 1,393 episodes of candidemia occurred in 1,348 patients. The incidence of candidemia episodes per 100,000 inhabitants increased from approximately 2 episodes in the early 1990s to 3 episodes in 2001 to 2003. The average annual incidences varied markedly between the age groups. The incidence was high in patients aged < 1 year and in patients aged > or = 70 years. In patients > or = 80 years of age, the incidence has increased during the last 3 years from an annual average of 6.5 to 15.6 cases/100,000 inhabitants in 2003. Four Candida species (C. albicans [70%], C. glabrata [13%], C. tropicalis [7%], and C. parapsilosis [6%]) accounted for 95.5% of the isolates. The species distribution has been constant during the 13-year study period. The distribution of the most important species varied with the age of the patient. In patients < 1 year of age, the majority of episodes were caused by C. albicans (91%). The occurrence of C. glabrata increased with age. In patients > or = 80 years of age, approximately 1/3 of all episodes were due to this species. All C. albicans strains were susceptible to fluconazole. The percentage of yeast isolates with decreased susceptibility to fluconazole (MICs > or = 16 microg/ml) was 10.7% during the first period of this study (1991 to 1996) and 11.7% during the second period (1997 to 2003).

Secular trends in nosocomial candidaemia in non-neutropenic patients in an Italian tertiary hospital

A retrospective study was performed in an Italian tertiary hospital to evaluate trends in candidaemia between 1992 and 2001, and to compare the characteristics of episodes of fungaemia between 1992--1997 and 1998--2001. In total, 370 episodes of candidaemia were identified, with an average incidence of 0.99 episodes/10 000 patient-days/year (range 0.49--1.29 episodes). On an annual trend basis, the overall incidence was essentially stable in surgical and medical wards, but decreased in intensive care units (ICUs) (p 0.0065). The average use of fluconazole was 37.9 g/10 000 patient-days/year (range 21.4--56.1 g), and did not change significantly during the 10-year period. Nearly two-thirds of patients were in ICUs at the onset of candidaemia, but none was neutropenic in either study period. Candida albicans remained the predominant species isolated (53.8% vs. 48.1%), followed by Candida parapsilosis, Candida glabrata and Candida tropicalis, the distribution of which did not change significantly. The 30-day crude mortality rate was essentially similar (44% vs. 35%) in both study periods. Thus the incidence of nosocomial candidaemia, although high in this institution, decreased among critically-ill patients during the 10-year period. This finding seemed to be related to an improvement in infection control practices, particularly regarding the prevention of intravascular catheter-related infections in ICUs. Although the overall use of fluconazole was considerable, no increase in azole-resistant non-albicans Candida spp. was detected.

Global trends in candidemia: Review of reports from 1995–2005

Candida species are an important cause of health care-related bloodstream infections (BSI). Understanding the current Candida BSI incidence trends, the dominant species causing disease, and the mortality associated with this infection are important to help guide therapeutic and prophylaxis measures. In this review, trends in the incidence of Candida BSI are assessed using data extracted from reports published worldwide during 1995 to 2005. The incidence trend of Candida BSI was found to be stable for most of the reports reviewed, and Candida albicans remains the most common species causing Candida BSIs. Surveillance to monitor the burden of disease and emergence of resistance, among the general patient population and among high risk patient populations, should be continued.

International, open-label, noncomparative, clinical trial of micafungin alone and in combination for treatment of newly diagnosed and refractory candidemia

Candida spp. are the fourth leading cause of bloodstream infections, and non-albicans species are increasing in importance. Micafungin is a new echinocandin antifungal agent with excellent in vitro activity against Candida spp. Pediatric, neonatal, and adult patients with new or refractory candidemia were enrolled into this open-label, noncomparative, international study. The initial dose of micafungin was 50 mg/d (1 mg/kg for patients <40 kg) for infections due to C. albicans and 100 mg/d (2 mg/kg for patients <40 kg) for infections due to other species. Dose escalation was allowed. Maximum length of therapy was 42 days. A total of 126 patients were evaluable (received at least five doses of micafungin). Success (complete or partial response) was seen in 83.3% patients overall. Success rates for treatment of infections caused by the most common Candida spp. were as follows: C. albicans 85.1%, C. glabrata 93.8%, C. parapsilosis 86.4%, and C. tropicalis 83.3%. Serious adverse events related to micafungin were uncommon. Micafungin shows promise as a safe and effective agent for the treatment of newly diagnosed and refractory cases of candidemia. Large-scale, randomized, controlled trials are warranted.

Seminational surveillance of fungemia in Denmark: notably high rates of fungemia and numbers of isolates with reduced azole susceptibility

The aim of this study was to present the first set of comprehensive data on fungemia in Denmark including the distribution of species and range of susceptibility to major antifungal compounds based on a seminational surveillance study initiated in 2003. The catchment area of the participating hospitals had a population of 2.8 million, or 53% of the Danish population. A total of 303 episodes of fungemia were registered (annual rate, 11 of 100,000 people or 0.49 of 1,000 hospital discharges). Candida species accounted for 97.4% of the fungal pathogens. C. albicans was the predominant species (63%), but the proportion varied from 57% to 72% among participating departments of clinical microbiology. C. glabrata was the second most frequent species (20%; range, 8% to 32%). C. krusei was a rare isolate (3%) and occurred only at two of the participating hospitals. Retrospective data retrieved from the Danish laboratory systems documented a continuous increase of candidemia cases since the early 1990s. For the 272 susceptibility-tested isolates, MICs of amphotericin B and caspofungin were within the limits expected for the species or genus. However, decreased azole susceptibility, defined as a fluconazole MIC of >8 microg/ml and/or itraconazole MIC of >0.125 microg/ml, was detected for 11 Candida isolates that were neither C. glabrata nor C. krusei. Including intrinsically resistant fungi, we detected decreased susceptibility to fluconazole and/or itraconazole in 87 (32%) current Danish bloodstream fungal isolates. We showed a continuous increase of fungemia in Denmark and an annual rate in 2003 to 2004 higher than in most other countries. The proportion of bloodstream fungal isolates with reduced susceptibility to fluconazole and/or itraconazole was also notably high.

Invasive Candida species infections: a 5 year population-based assessment

OBJECTIVES

Candida species have emerged as important causes of invasive infections and rates of resistance to standard antifungal therapies are rising. The objective of this study was to define the occurrence of, risk factors for, and antifungal susceptibilities of invasive Candida species infections in a large Canadian health region.

METHODS

Population-based surveillance was conducted for invasive Candida species infections in the Calgary Health Region during a 5 year period and susceptibility testing was performed.

RESULTS

The annual incidence of invasive Candida species infection was 2.9 per 100,000 population (0.2 and 2.8 per 100,000 for central nervous system and bloodstream infection, respectively). The very young and elderly were at highest risk for invasive Candida species infections. Several risk factors for developing invasive Candida species infection were identified with chronic haemodialysis, organ transplant recipient, and cancer patients at highest risk. Thirty percent (56/184; 43 susceptible, dose-dependent and 13 resistant) of isolates demonstrated reduced susceptibility to fluconazole. Only one (1%) isolate had reduced susceptibility to amphotericin B and six (3%) and three (2%) isolates had minimum inhibitory concentrations of >or=1 mg/L to voriconazole and caspofungin, respectively. Overall, 40% of patients died in-hospital for an annual mortality rate of 1.2 per 100,000.

CONCLUSIONS

Candida species are an important cause of invasive infection and patients with co-morbidities and extremes of age are at highest risk. Alternatives to fluconazole should be considered for initial empiric therapy in patients with severe invasive Candida species infections.

Candidaemia in an Irish tertiary referral hospital: epidemiology and prognostic factors

There were two parts to this study. Part 1 evaluated the epidemiology of Candida bloodstream isolates within the Southern Health Board (SHB) of Ireland from 1992 to 2003 by retrospective surveillance of all such isolates of patients reported from SHB hospitals to our laboratory database during that period. Part 2 reviewed candidaemia cases occurring in Cork University Hospital (CUH) from 1999 to 2003 using surveillance of all positive blood culture isolates in CUH microbiology laboratory during the 5-year period. In part 1, 250 Candida bloodstream isolates were reported in the SHB over 12 years. There was a pattern of decreasing percentage of C. albicans with time. Whereas in part 2, 63 cases of candidaemia were identified in CUH from 1999 to 2003. Candida albicans constituted 50% of all isolates, while C. parapsilosis and C. glabrata accounted for 21.2% and 18.2% respectively. Average annual incidence rate was 0.48 episodes/1000 admissions and 0.70 episodes/10 000 patient-days. Vascular catheters were the commonest source of candidaemia (61.9%) followed by the urinary tract (12.7%). Risk factors included exposure to multiple antibiotics (75%); central vascular catheterization (73%); multiple colonization sites (71%); severe gastrointestinal (GI) dysfunction (54%) and acute renal failure (43%). Crude 7-day and 30-day mortality rates were 20.6% and 39.7% respectively. Logistic regression multivariate analysis identified the following to be independent predictors for mortality: age > or =65 years [odds ratio (OR) 7.2, P = 0.013]; severe GI dysfunction (OR 10.6, P = 0.01); acute renal failure (OR 7.6, P = 0.022); recent/concurrent bacteraemia (OR 5.2, P = 0.042); endotracheal intubation (OR 7.7, P = 0.014); while major surgery was associated with a better prognosis (OR 0.05, P = 0.002). Appropriate antifungal treatment was also found to be associated with survival (Fisher's exact test, P < 0.001). The epidemiology of Candida bloodstream isolates within our health board had changed over the years. Incidence and mortality of candidaemia were relatively high in our hospital. Dysfunction of major organ systems and recent bacteraemia were found to predict mortality.

Candida species distribution in bloodstream cultures in Lyon, France, 1998–2001

In order to determine the types of Candida spp. isolated from bloodstream cultures in Lyon, France, a retrospective study of isolates collected at five different bacteriology laboratories from 1998 to 2001 was conducted. During this period Candida spp. were isolated from 190 patients hospitalized in the internal medicine (32%), hematology (23%) and surgery (23%) wards, and in intensive care units (22%). C. albicans was the leading cause of Candida infection (49.5%), followed by C. glabrata (12.6%) and C. parapsilosis (12.1%). Among the onco-hematology patients, the major cause of candidemia was C. krusei (34%), followed by C. albicans (19%), while these two species were identified in 4% and 59% of patients in the other wards, respectively. In the single onco-hematology ward that was specialized in treating acute myeloid leukemia, 14 C. krusei isolates were identified in this study, which contrasts with the single C. krusei isolate recorded between 1992 and 1996. Since C. krusei has inherent resistance to the antifungal agent fluconazole, prophylactic use of fluconazole in these patients was investigated, but no relationship between these two parameters was found.

Epidemiology and predictors of mortality in cases of Candida bloodstream infection: results from population-based surveillance, barcelona, Spain, from 2002 to 2003

We conducted population-based surveillance for Candida bloodstream infections in Spain to determine its incidence, the extent of antifungal resistance, and risk factors for mortality. A case was defined as the first positive blood culture for any Candida spp. in a resident of Barcelona, from 1 January 2002 to 31 December 2003. We defined early mortality as occurring between days 3 to 7 after candidemia and late mortality as occurring between days 8 to 30. We detected 345 cases of candidemia, for an average annual incidence of 4.3 cases/100,000 population, 0.53 cases/1,000 hospital discharges, and 0.73 cases/10,000 patient-days. Outpatients comprised 11% of the cases, and 89% had a central venous catheter (CVC) at diagnosis. Overall mortality was 44%. Candida albicans was the most frequent species (51% of cases), followed by Candida parapsilosis (23%), Candida tropicalis (10%), Candida glabrata (8%), Candida krusei (4%), and other species (3%). Twenty-four isolates (7%) had decreased susceptibility to fluconazole (MIC > or = 16 microg/ml). On multivariable analysis, early death was independently associated with hematological malignancy (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.1 to 10.4). Treatment with antifungals (OR, 0.05; 95% CI, 0.01 to 0.2) and removal of CVCs (OR, 0.3; 95% CI, 0.1 to 0.9) were protective factors for early death. Receiving adequate treatment, defined as having CVCs removed and administration of an antifungal medication (OR, 0.2; 95% CI, 0.08 to 0.8), was associated with lower odds of late mortality; intubation (OR, 7.5; 95% CI, 2.6 to 21.1) was associated with higher odds. The incidence of candidemia and prevalence of fluconazole resistance are similar to other European countries, indicating that routine antifungal susceptibility testing is not warranted. Antifungal medication and catheter removal are critical in preventing mortality.

In vitro susceptibilities of bloodstream isolates of Candida species to six antifungal agents: results from a population-based active surveillance programme, Barcelona, Spain, 2002–2003

OBJECTIVES

The antifungal drug susceptibilities of 351 isolates of Candida species, obtained through active laboratory-based surveillance in the period January 2002-December 2003, were determined (Candida albicans 51%, Candida parapsilosis 23%, Candida tropicalis 10%, Candida glabrata 9%, Candida krusei 4%).

METHODS

The MICs of amphotericin B, flucytosine, fluconazole, itraconazole, voriconazole and caspofungin were established by means of the broth microdilution reference procedure of the European Committee on Antibiotic Susceptibility Testing.

RESULTS AND CONCLUSIONS

Amphotericin B and flucytosine were active in vitro against all strains. A total of 24 isolates (6.8%) showed decreased susceptibility to fluconazole (MIC > or = 16 mg/L) and 43 (12.3%) showed decreased susceptibility to itraconazole (MIC > or = 0.25 mg/L). Voriconazole and caspofungin were active in vitro against the majority of isolates, even those that were resistant to fluconazole.

Candidaemia in allogeneic stem cell transplant recipients: low risk without fluconazole prophylaxis

Invasive fungal infections (IFI) are common in allogeneic SCT recipients. We have reviewed our experience of IFI with special reference to candidaemia in 685 adult patients transplanted in 1983-2002. The donor was a matched sibling in 505 patients and an unrelated donor in 180 patients. A BM graft was used in 561 patients and a PB graft in 124 patients. Fluconazole prophylaxis was not used during the study period. Definite or probable IFI was observed in 60 patients (8.7%) with a dominance of Aspergillus infections (46 patients, incidence 6.7%). Candidaemia was found only in nine patients (1.3%). The causative agents were Candida albicans (n=8), C. krusei (n=2), and C. glabrata (n=1); in two patients, two causative agents were found. The median time to the diagnosis of candidaemia was 53 days (range 6-249 days) post transplant. Seven patients were neutropaenic at diagnosis, and four patients had experienced acute GVHD. All patients received antifungal therapy, but only one patient was cured. According to this study, candidaemia was a rare event in allogeneic SCT recipients. Thus, systematic prophylaxis against Candida infections might not be indicated. The prognosis of established infections is still poor due to comorbid conditions, notably GVHD.

Geographic variation in the susceptibilities of invasive isolates of Candida glabrata to seven systemically active antifungal agents: a global assessment from the ARTEMIS Antifungal Surveillance Program conducted in 2001 and 2002

We examined the susceptibilities to amphotericin B, flucytosine, fluconazole, posaconazole, ravuconazole, voriconazole, and caspofungin of 601 invasive isolates of Candida glabrata and grouped the isolates by geographic location: North America (331 isolates), Latin America (58 isolates), Europe (135 isolates), and Asia-Pacific (77 isolates). Caspofungin (MIC at which 90% of isolates tested are susceptible [MIC(90)], 0.12 microg/ml; 100% of strains are susceptible [S] at a MIC of Collapse

Key Words Collapse

MESH Headings

• Antifungal Agents/pharmacology
• Candida glabrata/drug effects
• Drug Resistance, Fungal
• Microbial Sensitivity Tests
• Time Factors

Collapse

Grants Collapse

Affiliation(s)

M A Pfaller Department of Pathology, Roy J and Lucille A Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
S A Messer
L Boyken
S Tendolkar
R J Hollis
D J Diekema

Collapse

Collaborators Collapse

Clinical factors associated with fluconazole resistance and short-term survival in patients with Candida bloodstream infection

In a 1-year national surveillance program of Candida bloodstream infections in Japan, clinical factors predicting fluconazole resistance and survival of the patients were analyzed. Blood isolates and complete clinical histories were obtained from 326 patients. Fluconazole-resistant isolates were found in 15 (4.6%) of the cases. Univariate analysis of the demographic and clinical factors associated with fluconazole resistance revealed that age, hematologic malignancy, neutropenia, and immunosuppression were of statistical significance. A multiple logistic regression model showed that only hematologic malignancy as the underlying disease (odds ratio, 6.6; 95% confidence interval, 1.6-26.9; P=0.009) was independently associated with resistance. In 242 cases in which data regarding management and prognosis were available, the 30-day survival rate was 68.4%. In the univariate analysis of factors predicting survival, a significant association was found for Candida species, age of the patient, neutropenia, recent abdominal surgery, removal of the central venous catheter, and use of appropriate antifungal therapy. In the multivariate analysis, removal of the central venous catheter (odds ratio, 6.0; 95% confidence interval, 2.2-16.1; P<0.001) and the use of appropriate therapy (odds ratio, 2.1; 95% confidence interval, 1.1-4.1; P=0.03) were independent factors significantly associated with survival after the diagnosis of Candida bloodstream infection.