Trends in species causing fungaemia in a tertiary care medical centre over 12 years

Imaging fungal infections in children

Fungal infections in children rarely occur, but continue to have a high morbidity and mortality despite the development of newer antifungal agents. It is essential for these infections to be diagnosed at the earliest possible stage so appropriate treatment can be initiated promptly. The addition of high-resolution computer tomography (HR CT) has helped in early diagnosis making; however, it lacks both sensitivity and specificity. Metabolic changes precede anatomical changes and hybrid imaging with positron emission tomography (PET) integrated with imaging modalities with high anatomical resolution such as CT or magnetic resonance imaging (MRI) is likely to detect these infections at an earlier stage with higher diagnostic accuracy rates. Several authors presented papers highlighting the advantages of PET/CT in imaging fungal infections. These papers, however, usually involve a limited number of patients and mostly adults. Fungal infections behave different in children than in adults, since there are differences in epidemiology, imaging findings, and response to treatment with antifungal drugs. This paper reviews the literature and explores the use of hybrid imaging for diagnosis and therapy decision making in children with fungal infections.

Controversies in Candida management

Invasive candidiasis (IC) is associated with increased morbidity and mortality. Although advances in diagnosis and management of this infection have been reached, there remain several controversies. The aim of this review is to tackle some of these controversies and shed light on studies that support the different sides of the arguments. Regarding central line-associated candidaemia, the current evidence appears to be more in favour of early central line removal whenever possible. Otherwise, antifungal agents such as echinocandins or polyenes should be the preferred agents. In the setting of infection with Candida parapsilosis and in light of the high minimum inhibitory concentrations (MICs) to echinocandins, azoles have been considered the preferred treatment agents. However, a recent study appears to indicate that empirical echinocandin use was not associated with a worse outcome when the isolated species was C. parapsilosis. Different strategies of antifungal treatment have been considered, namely prophylactic, empirical, pre-emptive or directed therapies. Whilst there is consensus on the need for prophylaxis in high-risk cancer patients, especially haematological malignancy and stem cell transplant populations, it remains debatable whether prophylaxis is of benefit in very low birthweight infants and in intensive care unit (ICU) patients. In the era of antifungal resistance and where antifungal stewardship has been advocated, pre-emptive therapy based on predictive models with various Candida risk scores and sensitive non-culture-based biomarkers such as β-d-glucan appears to be a more cost-effective approach. Future efforts should be directed to optimise clinical predictive models and reliable biomarkers for early detection of IC.

Identification of Candida Species Using MP65 Gene and Evaluation of the Candida albicans MP65 Gene Expression in BALB/C Mice

Background:

Systemic candidiasis is a major public health concern. In particular, in immunocompromised people, such as patients with neutropenia, patients with Acquired Immune Deficiency Syndrome (AIDS) and cancer who are undergoing antiballistic chemotherapy or bone marrow transplants, and people with diabetes. Since the clinical signs and symptoms are nonspecific, early diagnosis is often difficult. The 65-kDa mannoprotein (MP65) gene of Candida albicans is appropriate for detection and identification of systemic candidiasis. This gene encodes a putative b-glucanase mannoprotein of 65 kDa, which plays a major role in the host-fungus relationship, morphogenesis and pathogenicity.

Objectives:

The current study aimed to identify different species of Candida (C. albicans, C. glabrata and C. parapsilosis) using the Polymerase Chain Reaction (PCR) technique and also to evaluate C. albicans MP65 gene expression in BALB/C mice.

Materials and Methods:

All yeast isolates were identified on cornmeal agar supplemented with tween-80, germ tube formation in serum, and assimilation of carbon sources in the API 20 C AUX yeast identification system. Polymerase Chain Reaction was performed on all samples using species-specific primers for the MP65 65 kDa gene. After RNA extraction, cDNA synthesis was performed by the Maxime RT Pre Mix kit. Candida albicans MP65 gene expression was evaluated by quantitative Real-Time (q Real-Time) and Real-Time (RT) PCR techniques. The 2-ΔΔCT method was used to analyze relative changes in gene expression of MP65. For statistical analysis, nonparametric Wilcoxon test was applied using the SPSS version 16 software.

Results:

Using biochemical methods, one hundred, six and one isolates of clinical samples were determined as C. albicans, C. glabrata and C. parapsilosis, respectively. Species-specific primers for PCR experiments were applied to clinical specimens, and in all cases a single expected band for C. albicans, C. glabrata and C. parapsilosis was obtained (475, 361 and 124 base pairs, respectively). All species isolated by culture methods (100% positivity) were evaluated with PCR using species-specific primers to identify Candida species. Relative expression of Mp65 genes increased significantly after C. albicans injection into the mice (P < 0.05).

Conclusions:

The results of the current study showed that the PCR method is reproducible for rapid identification of Candida species with specific primers. Mp65 gene expression of C. albicans after injection into the mice was 2.3 folds higher than before injection, with this difference being significant. These results indicated that increase of Mp65 gene expression might be an early stage of infection; however definitive conclusions require further studies.

In vitro susceptibility of Candida species to four antifungal agents assessed by the reference broth microdilution method

This study was performed to determine the distribution of Candida species isolated from the blood cultures of the patients hospitalized in our hospital and to investigate their antifungal susceptibility. Candida strains were identified at species level by using classical methods and API ID 32C (bioMerieux, France) identification kits. The susceptibility of the strains to amphotericin B, fluconazole, voriconazole, and caspofungin was evaluated by using the reference broth microdilution method in document M27-A3 of the Clinical and Laboratory Standards Institute. Of the 111 Candida strains isolated, 47.7% were identified as C. albicans and 52.3% as non-albicans Candida strains. The MIC ranges were 0.03–1 μg/mL for amphotericin B, 0.125–≥64 μg/mL for fluconazole, 0.03–16 μg/mL for voriconazole, and 0.015–0.25 μg/mL for caspofungin. All Candida strains were susceptible to amphotericin B and caspofungin. 10.8% isolates were resistant to fluconazole and 8.1% isolates were dose-dependent susceptible. While 0.9% isolate was resistant to voriconazole, 0.9% isolate was dose-dependent susceptible. In our study, C. albicans and C. parapsilosis were the most frequently encountered agents of candidemia and it was detected that voriconazole with a low resistance rate might also be used with confidence in the treatment of infections occurring with these agents, primarily besides amphotericin B and caspofungin.

Antifungal prophylaxis in pediatric hematology/oncology: new choices & new data

A severe complication of the treatment of pediatric cancers is the development of an invasive fungal infection (IFI). The data to support antifungal prophylaxis in pediatric oncology patients derive primarily from adult patients, and thus the optimal agent to utilize is not clear. Fluconazole has been a standard option, but agents with antimold activity are now available, each with limitations. Pediatric dosing for voriconazole and posaconazole is uncertain and multiple drug interactions exist. The echinocandins are well-tolerated, but only available in intravenous form. Ultimately, studies demonstrating biologic risk factors for the development of IFI may lead to personalized prophylactic strategies.

New regulators of biofilm development in Candida glabrata

Biofilm formation plays an important role in fungal pathogenesis. In this work, we used a genetic screen in order to identify and characterize genes involved in the formation of biofilms by the opportunistic fungal pathogen Candida glabrata. We identified the Cst6p transcription factor as a negative regulator of the EPA6 gene that encodes an adhesin central to C. glabrata biofilm formation. Analysis of single and double mutant strains showed that Cst6p acts in a pathway independent of the Yak1/Sir4 pathway also known to regulate expression of EPA6 and consequently biofilm formation. In contrast, we showed that the chromatin remodelling Swi/Snf complex positively regulates biofilm formation in C. glabrata. RT-qPCR experiments demonstrated that EPA6 expression, and thus biofilm formation, depends on the integrity of the Sir complex. Finally, we showed that Swi/Snf-dependent regulation of biofilm formation is adhesin-specific.

Geographic distribution of endemic fungal infections among older persons, United States

TOC summary: Incidence was highest for histoplasmosis and blastomycosis in the Midwest and for coccidioidomycosis in the West.

To investigate the epidemiology and geographic distribution of histoplasmosis, coccidioidomycosis, and blastomycosis in older persons in the United States, we evaluated a random 5% sample of national Medicare data from 1999 through 2008. We calculated national, regional, and state-based incidence rates and determined 90-day postdiagnosis mortality rates. We identified 776 cases (357 histoplasmosis, 345 coccidioidomycosis, 74 blastomycosis). Patient mean age was 75.7 years; 55% were male. Histoplasmosis and blastomycosis incidence was highest in the Midwest (6.1 and 1.0 cases/100,000 person-years, respectively); coccidioidomycosis incidence rate was highest in the West (15.2). On the basis of available data, for 86 (11.1%) cases, there was no patient exposure to a traditional disease-endemic area. Knowledge of areas where endemic mycosis incidence is increased may affect diagnostic or prevention measures for older adults at risk.

Gene Expression and Identification Related to Fluconazole Resistance of Candida glabrata Strains

Objectives

Candida glabrata has become one of the most common causes of Candida bloodstream infections worldwide. Some strains of C. glabrata may be intermediately resistant to all azoles. The several possible mechanisms of azole resistance have been reported previously, but the exact resistant mechanism is not clear. In this study, we identified differentially expressed genes (DEGs) of fluconazole-resistant C. glabrata and compared the gene expression of fluconazole-resistant strains with that of fluconazole-susceptible strains to identify gene corresponding to fluconazole resistance.

Methods

Using antifungal susceptibility test, several C. glabrata strains were selected and used for further study. The expression of CgCDR1 and CgCDR2 genes was investigated by slot hybridization against fluconazole-susceptible, -resistant, and resistant-induced strains. In addition, ERG3 and ERG11 genes were sequenced to analyze DNA base substitution. DEGs were identified by reverse transcription-polymerase chain reaction using DEG kit composed of 120 random primers.

Results

In slot hybridization, CgCDR1 gene was expressed more than CgCDR2 gene in resistant strains. Though base substitution of ERG11 and ERG3 genes was observed in several base sequences, just one amino acid change was identified in resistant strain. In the results of reverse transcription-polymerase chain reaction, 44 genes were upregulated and 34 genes were downregulated. Among them, adenosine triphosphate-binding cassette transporter-related genes, fatty acid desaturase, lyase, and hypothetical protein genes were upregulated and aldehyde dehydrogenase, oxidoreductase, and prohibitin-like protein genes were downregulated. Other DEGs were also identified.

Conclusion

This study showed that CgCDR1 gene was more closely related to fluconazole resistance of C. glabrata than CgCDR2 gene. In addition, several other genes related with fluconazole resistance of C. glabrata were identified.

Candidemia in children

Seriously ill or immunocompromised children are at increased risk of invasive fungal infections, particularly candidemia. Candida albicans and Candida parapsilosis are the two most frequent causes of candidemia in pediatric patients. Candidemia in children is associated with high morbidity and mortality, increased length of hospital stays, and higher healthcare costs. Early effective antifungal therapy is the key to improved outcomes. Risk factors for candidemia may be used to identify patients suitable for empiric therapy. Such risk factors include prolonged stay in an intensive care unit, immunosuppression, prior bacterial infection, and recent surgery, as well as the use of a central venous catheter, mechanical ventilation, and/or total parenteral nutrition. Recent guidelines from the Infectious Diseases Society of America recommend consideration of fluconazole or an echinocandin for empiric therapy in suitable candidates, with a preference for an echinocandin in patients with moderate-to-severe disease, recent azole exposure, or high risk of Candida glabrata or Candida krusei infection. Fluconazole or an echinocandin is also preferred initial therapy for non-neutropenic candidemia, depending on disease severity and other characteristics. The guidelines recommend treatment with an echinocandin or lipid formulation of amphotericin B for most patients with neutropenic candidemia, although fluconazole is identified as an alternative for less critically ill patients without recent azole exposure. Risk factors for candidemia - and, hence, criteria for prophylaxis - are less well established in older children than in neonates. Further research is needed to better establish criteria for antifungal prophylaxis in children at high risk for candidemia.

The impact of a PCR assay for candidemia on antifungal drug prescribing in critical care: an interrupted time series pilot study

SUMMARY OBJECTIVE

To evaluate the feasibility of conducting a definitive study to assess the impact of introducing a rapid PCR-based test for candidemia on antifungal drug prescribing.

METHOD

Prospective, single centre, interrupted time series study consisting of three periods of six months' duration. The assay was available during the second period, during which the PCR assay was available for routine use by physicians Monday-Friday with guaranteed 24-h turnaround time. For each period total antifungal drug use, expressed as treatment-days, was recorded and an adjustment was made to exclude estimated use for proven candidemia. Also, during the intervention period, antifungal prescribing decisions for up to 72 h after each PCR result became available were recorded as either concordant or discordant with that result.

RESULTS

While overall antifungal use remained relatively stable throughout, after adjustment for candidemia, there was a 38% reduction in use following introduction of the PCR test; however, this was nonsignificant at the 95% level. During the intervention period overall concordance between the PCR result and prescribing decisions was 84%.

CONCLUSIONS

The PCR assay for candidemia was requested, prescribing decisions were generally concordant with the results produced and there was an apparent decrease in antifungal prescription, although this was sustained even after withdrawal of the intervention; these findings should be more thoroughly evaluated in a larger trial.

Epidemiology, incidence and risk factors for invasive candidiasis in high-risk patients

Candida spp. are an increasing cause of bloodstream infections, and are associated with high morbidity and mortality in both neutropenic and non-neutropenic critically ill patients. Risk factors associated with candidaemia are diverse and include exposure to broad spectrum antimicrobial agents, mucosal colonization by Candida spp., indwelling vascular catheters, prior surgery and cancer chemotherapy. During the last 20 years, there has been an increasing incidence worldwide in invasive candidiasis, but differences in geographical epidemiology are emerging, in particular regarding a shift towards non-albicans species. This shift has been correlated with routine fluconazole prophylaxis adopted in some patients, and the intrinsic/acquired azole resistance of Candida spp., which represents a very real problem, in terms of both selecting the appropriate empirical therapeutic approach and making prophylactic choices.

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.

Trends in candidemia and antifungal susceptibility in a university hospital in Northern Ireland 2001-2006

OBJECTIVES

To describe the species distribution and antifungal susceptibility trends for documented episodes of candidemia at the Royal Hospitals, Belfast, 2001-2006.

METHODS

Laboratory-based retrospective observational study of all episodes of candidemia.

RESULTS

There were 151 episodes of candidemia. The species recovered were: 96 C. albicans; 26 C. glabrata; 18 C. parapsilosis; five C. tropicalis; four C. guilliermondii; one C. famata and one C. dubliniensis. We separated the data into two periods 2001-2003 and 2004-2006; contrary to the findings of other investigators, there was a notable trends toward increasing frequency of C. albicans and decreasing frequency of non-albicans species over time. Although the proportion of C. albicans, C. parapsilosis and C. tropicalis isolates susceptible to fluconazole was unchanged over time, a trend of decreased susceptibility of C. glabrata to fluconazole was noted over the six-year period. Overall, 73% and 7.7% of C. glabrata isolates had susceptible-dose-dependent and resistant phenotypes, respectively. The percentage of C. glabrata isolates susceptible to fluconazole (MIC <8 microg/ml) decreased from 36% in 2001-2003 to 0% in 2004-2006. Flucytosine resistance was detected in only 4 (2.7%) isolates. None of the isolates had an amphotericin B MIC <1 microg/ml.

CONCLUSION

A shift towards increasing dominance of C. albicans contrasts both with reports from other countries and previous data from Northern Ireland. Upwards fluconazole MIC drift among C. glabrata has important implications for empirical therapeutic decisions.

Rapid simultaneous detection and identification of six species Candida using polymerase chain reaction and reverse line hybridization assay

The aim of this study was to develop and evaluate PCR based reverse line blot (RLB) hybridization assay for rapid detection of the most common Candida isolates from clinical specimens. A pair of universal primers targeting the ITS2 region of the gene from 28S rRNA to 5.8S rRNA was designed for PCR amplification of DNA from 6 Candida species (C. albicans, C. tropicalis, C. krusei, C. glabrata, C. parapsilosis, C. dubliniensis), the reverse primer was biotin labeled. PCR products, which were 302-441 bp length, were hybridized with 6 specific oligonucleotides probes immobilized on a nylon membrane. These 6 probes proved specific (they hybridized with only their target molecules). The assay was shown to be sensitive in detecting yeast to a concentration of 10 CFU/ml. This method was used to test 100 isolates and 200 vaginal swabs. The results agreed with those of culture for all but 3 of 100 isolates. Sequencing was performed on these 3 samples and confirmed that the culture results were inaccurate. Our results show the PCR-RLB positive rate (49%) is higher than culture (39%) and smear microscopic screening (27%) (P<0.05). In conclusion, the PCR/RLB developed in this study is specific and offers increased sensitivity compared to culture for the detection of Candida species in swab specimens. Moreover, the improved detection of cases of polycandidal candidiasis is advantageous.

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.

Invasive Candidiasis

Invasive candidiasis remains an important nosocomial infection that continues to present major diagnostic and therapeutic challenges to the clinician. Changes in the epidemiology of this disorder have occurred for many reasons, and included especially the extensive use of prophylactic antifungal agents, broad-spectrum antibacterial agents, and medical devices (eg, chronic indwelling intravascular catheters). The diagnosis of IC remains elusive in many patients, and there is a critical need for improved diagnostics that will provide clinicians the opportunity to intervene earlier in the course of disease. Newer antifungal agents offer promise in the treatment of candidemia and other forms of IC, but the optimal use of these agents, particularly in the approach to non-albicans Candida infections, needs to be explored in more detail. Furthermore, despite an overwhelming amount of data concerning risk factors and excess mortality associated with the development of IC, there is no consistent approach to treatment and primary prevention among individuals who are deemed to be at highest risk for this complication. Research that focuses on these important clinical areas could provide valuable insights into the diagnosis and management of this common and evolving infection.

Epidemiological trends in nosocomial candidemia in intensive care

BACKGROUND

Infection represents a frequent complication among patients in Intensive Care Units (ICUs) and mortality is high. In particular, the incidence of fungal infections, especially due to Candida spp., has been increasing during the last years.

METHODS

In a retrospective study we studied the etiology of candidemia in critically ill patients over a five-year period (1999-2003) in the ICU of the San Martino University Hospital in Genoa, Italy.

RESULTS

In total, 182 episodes of candidaemia were identified, with an average incidence of 2.22 episodes/10,000 patient-days/year (range 1.25-3.06 episodes). Incidence of candidemia increased during the study period from 1.25 in 1999 to 3.06/10,000 patient-days/year in 2003. Overall, 40% of the fungemia episodes (74/182) were due to C.albicans, followed by C. parapsilosis (23%), C.glabrata (15%), C.tropicalis (9%) and other species (13%). Candidemia due to non-albicans species increased and this was apparently correlated with an increasing use of azoles for prophylaxis or empirical treatment.

CONCLUSION

The study demonstrates a shift in the species of Candida causing fungemia in a medical and surgical ICU population during a 5 year period. The knowledge of the local epidemiological trends in Candida species isolated in blood cultures is important to guide therapeutic choices.

Use of denaturing high-performance liquid chromatography for rapid detection and identification of seven Candida species

A novel denaturing high-performance liquid chromatography (DHPLC)-based technique allows rapid high-resolution analysis of PCR products. We used this technique for unequivocal molecular identification of seven Candida species. We show the application of this PCR/DHPLC approach for direct detection and identification of yeast species from blood cultures and for detection of Candida colonization in the gastrointestinal tract of allogeneic transplant patients.

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.

Characteristics of candidaemia with Candida-albicans compared with non-albicans Candida species and predictors of mortality

Candidaemia due to non-albicans Candida species is increasing in frequency. We describe 272 episodes of candidaemia, define parameters associated with Candida albicans and other Candida species, and analyse predictors associated with mortality. Patients with C. albicans (55%) had the highest fatality rate and frequently received immunosuppressive therapy, while patients with Candida parapsilosis (16%) had the lowest fatality and complication rates. Candida tropicalis (16%) was associated with youth, severe neutropenia, acute leukaemia or bone marrow transplantation, Candida glabrata (10%) was associated with old age and chronic disease, and Candida krusei (2%) was associated with prior fluconazole therapy. The overall fatality rate was 36%, and predictors of death by multi-variate analysis were shock, impaired performance status, low serum albumin and congestive heart failure. Isolation of non-albicans Candida species, prior surgery and catheter removal were protective factors. When shock was excluded from analysis, antifungal therapy was shown to be protective. Unlike previous concerns, infection with Candida species other than C. albicans has not been shown to result in an increased fatality rate.

Candida glabrata Fungemia: Experience in a Tertiary Care Center

BACKGROUND

During the past decade, Candida glabrata has emerged as an important cause of fungemia. We reviewed demographic data, risk factors, treatment, and outcomes associated with C. glabrata fungemia from 1995-2002 and performed susceptibility testing of isolates.

METHODS

Data on all episodes of fungemia were prospectively recorded, and the associated isolates were saved. Medical records were reviewed retrospectively. Susceptibility testing was performed for fluconazole, itraconazole, and voriconazole.

RESULTS

C. glabrata caused 103 (17%) of 609 fungemic episodes during the 8-year period that we studied. Medical records and isolates were available for 94 episodes that occurred in 91 patients. The patients included 42 men and 49 women. The mean age was 51 years. Thirty-four episodes (36%) occurred in patients >60 years old; only 3 episodes occurred in patients <1 year old. The most common predisposing factors were use of broad-spectrum antibiotics (in 86% of episodes), use of central venous catheters (77%), stay in an intensive care unit (48%), renal failure (46%), and receipt of parenteral nutrition (45%). Of the 94 episodes, 83 were treated with antifungal agents. The overall mortality rate at day 30 was 29%. For the 11 episodes that were not treated, the mortality rate was 64% (7 of 11 episodes). Outcome appeared to be unrelated to whether fluconazole or amphotericin B was administered. In vitro, 60% of isolates were resistant to fluconazole, 83% to itraconazole, and 44% to voriconazole. Susceptibility to these azoles did not change over the 8 years of the study.

CONCLUSION

C. glabrata fungemia was most often seen in older adults and was associated with a mortality rate of 29%. Outcomes appeared to be unrelated to in vitro susceptibility results and to the antifungal agent used.

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.

Use of amphotericin B lipid complex in elderly patients

OBJECTIVES

The safety and effectiveness of amphotericin B lipid complex (ABLC) treatment in elderly patients was investigated using a large multicenter database.

METHODS

Data analysis was conducted on retrospectively collected patient data from 572 patients >65 years of age and 2930 patients < or =65 years of age treated for fungal infections at 160 North American hospitals.

RESULTS

Patients were typically treated with ABLC for Candidiasis, multiple fungal pathogen infections and Aspergillosis, or were treated empirically. The median cumulative dose of ABLC in patients >65 years of age and those 65 years of age was similar (3000 and 3258 mg, respectively, P=0.127). Despite higher median pretreatment serum creatinine (S-Cr) among patients >65 years of age (1.7 mg/dl vs. 1.4 mg/dl, respectively), both groups showed only a 0.1mg/dl median S-Cr change from baseline by the end of therapy (P=0.525). Clinical response was 56 and 51%, respectively, in patients >65 years of age and patients 65 years of age or younger (P=0.049).

CONCLUSIONS

This study suggests that ABLC can be safely and effectively used in the treatment of invasive fungal disease in elderly patients.

Identification of clinically relevant yeasts by PCR/RFLP

For molecular diagnosis of fungal disease using DNA amplification procedures in the routine laboratory, choice of appropriate target structures and rapid and inexpensive identification of amplification products are important prerequisites. Most diagnostic procedures described thus far are characterized by limited applicability, considerable cost for laboratory equipment or low power of discrimination between species. This study aimed at identification of a PCR target appropriate for diagnosis of clinically relevant yeasts and an affordable procedure for characterization of the PCR products to the species level. Here, we describe a PCR-based system using amplification of intergenic spacers ITS1 and ITS2 and restriction length polymorphism of PCR products after sequence-specific enzymatic cleavage. We show the evaluation of the system for clinically relevant Candida species. The simple and inexpensive procedure should be instrumental for rapid identification of medically important yeasts.

Epidemiology of Candida species infections in critically ill non-immunosuppressed patients

A substantial proportion of patients become colonised with Candida spp during hospital stay, but only few subsequently develop severe infection. Clinical signs of severe infection manifest early but lack specificity until late in the course of the disease, thus representing a particular challenge for diagnosis. Mostly nosocomial, invasive candidiasis occurs in only 1-8% of patients admitted to hospitals, but in around 10% of patients housed in intensive care units where it can represent up to 15% of all nosocomial infections. We review the epidemiology of invasive candidiasis in non-immunocompromised, critically ill patients with special emphasis on disease trends over time, pathophysiology, diagnostic approach, risk factors, and impact. Recent epidemiological data suggesting that the emergence of non-albicans candida strains with reduced susceptibility to azoles, previously linked to the use of new antifungals for empiric and prophylactic therapy in immunocompromised patients, may not have occurred in the critically ill. Management of invasive candidiasis in these patients will be addressed in the December issue of The Lancet Infectious Diseases.

Fungal infections in older adults

Invasive fungal infections have become an increasing problem in older adults. Infections with opportunistic fungi have increased because older patients are more likely to be considered for transplantation, receive aggressive regimens of chemotherapy for cancer, and take immunosuppressive drugs for nonmalignant diseases. In addition, healthy older adults are now more likely to travel extensively and to indulge in outdoor activities, which put them at risk for exposure to endemic mycoses. Although many of the clinical manifestations of fungal infections in older and younger adults are similar, there are aspects of histoplasmosis, aspergillosis, and cryptococcosis that are unique to older patients. Treatment of older adults with amphotericin B is difficult because of the intrinsic nephrotoxicity of the drug. Although they are less toxic, azoles must be used carefully for treatment of older adults, who are more likely to experience serious drug-drug interactions than are younger persons.