Analysis of factors related to the occurrence of chronic disseminated candidiasis in patients with acute leukemia in a non-bone marrow transplant setting: a follow-up study

Chronic disseminated candidiasis manifesting as hepatosplenic abscesses among patients with hematological malignancies

BACKGROUND

The outcomes of deep-seated abscesses attributed to chronic disseminated candidiasis (CDC) in patients with hematological malignancies have rarely been reported in recent years.

METHODS

We retrospectively reviewed and analyzed the data of patients with hematological malignancies who received a diagnosis of CDC at a medical center in Taiwan between 2008 and 2013.

RESULTS

Sixty-one patients (32 men and 29 women) were diagnosed with CDC. The median age was 51 years (range: 18-83). The overall incidence of CDC was 1.53 per 100 patient-years in patients with hematological malignancies between 2008 and 2013. The highest incidence of CDC was 4.3 per 100 patient-years for acute lymphoblastic leukemia, followed by 3.6 for acute myeloid leukemia. We detected 3 (4.9%) proven, 13 (21.3%) probable, and 45 (73.8%) possible cases of CDC. A total of 13 patients had positive blood cultures for Candida species: C. tropicalis (8), C. albicans (2), C. glabrata (2), and C. famata (1). The median duration of antifungal treatment was 96 days (range: 7-796 days). Serial imaging studies revealed that the resolution rate of CDC was 30.0% at 3 months and 54.3% at 6 months. Five patients (8.2%) had residual lesions that persisted beyond one year. A multivariate analysis of the 90-day outcome revealed that shock was the only independent prognostic factor of 90-day survival in patients with CDC.

CONCLUSION

The incidence of CDC did not decrease between 2008 and 2013. Patients with acute leukemia had a higher risk of CDC than those with other hematological malignancies. Imaging studies conducted at 6 months after diagnosis revealed that only half of the patients showed complete resolution. CDC requires prolonged treatment, and serial imaging at 6 months interval is suggested. Shock is the only independent prognostic factor of 90-day survival in patients with CDC.

Discontinuation of antimicrobial therapy in adult neutropenic haematology patients: A prospective cohort

OBJECTIVES

Antibiotics for febrile neutropenia (FN) in acute myeloid leukaemia (AML) patients undergoing intensive chemotherapy are usually maintained until neutropenia resolution, because of the risk of uncontrolled sepsis in this vulnerable population. This leads to unnecessarily prolonged antimicrobial therapy.

METHODS

Based on ECIL-4 recommendations, we modified our management strategy and discontinued antibiotics after a pre-established duration in patients treated for a first episode of FN between August 2014 and October 2017.

RESULTS

Antibiotics were stopped during 62 FN episodes, and maintained in the control group (n = 13). Median age of patients was 54 years. A total of 39 (63%) patients received induction and 23 (37%) consolidation chemotherapy; 36 (58%) patients had fever of unknown origin. Median neutropenia length was 26 days (IQR 24-30). Antibiotics were started at day 9 (IQR 5-13). Most patients received piperacillin-tazobactam (56%) or cefepime (32%). Antimicrobial therapy was longer in the control group than in the policy compliant group, 10 (IQR 7-16) vs. 19 days (IQR 15-23), P = 0.0001. After antibiotics discontinuation, 20% patients experienced fever recurrence, within 5.5 days (IQR 3-7.5). None of these febrile episodes were severe and 80% patients remained afebrile, with neutrophil recovery occurring within 5 days (IQR 2-8.5). Overall, 287 antibiotics days were spared; this represents 49% of all days with antibiotics. No patient had died at day 30 from intervention; six died during late follow-up, two from graft-versus-host disease and four from relapsed or refractory leukaemia.

CONCLUSIONS

Discontinuing antibiotics in neutropenic AML patients treated for a first episode of FN is safe, and results in significant antibiotic sparing.

Clinical characteristics and outcomes of patients with chronic disseminated candidiasis who need adjuvant corticosteroid therapy

We performed a retrospective study involving 21 patients with chronic disseminate candidiasis (CDC) and 38 patients with candidemia. Neutropenia of >2 weeks' duration was more common in those with CDC (71%) than in those with candidemia (26%, P < .001), and the azole-resistant rate in patients with CDC (5%) was lower than that in those with candidemia (29%, P = .03). Of the 21 patients with CDC, five (24%) needed adjuvant corticosteroid therapy due to persistent debilitating fever (median, 19 days). Rapid defervescence (median, 5 days) occurred after adjuvant corticosteroid therapy. However, there were no significant differences in 90-day mortality between CDC patients with and without corticosteroid therapy. Further prospective data are needed to define the role of steroids in this setting.

Huge Hepatic Fungal Inflammatory Pseudotumor Misdiagnosed as Primary Hepatocellular Carcinoma

Fungal inflammatory pseudotumor (FIPT) of the liver is a rare disease that may be mistaken for a malignant tumor. It is difficult to diagnose because of its nonspecific clinical and imaging features. We report the case of a 46-year-old Asian man who presented with a mass in the right upper quadrant of the abdomen. The patient had undergone transcatheter arterial chemoembolization therapy at another institution 6 months earlier, but the mass had continued to enlarge. He had no history of chronic hepatitis B, and the serum α-fetoprotein was negative. Contrast-enhanced ultrasonography and computed tomography images were suggestive of hepatocellular carcinoma. However, ultrasound-guided biopsy revealed features of chronic inflammation. The mass was resected and found to be an FIPT. We discuss the details of the case and review related articles.

Fluconazole non-susceptible breakthrough candidemia after prolonged low-dose prophylaxis: a prospective FUNGINOS study

OBJECTIVES

Breakthrough candidemia (BTC) on fluconazole was associated with non-susceptible Candida spp. and increased mortality. This nationwide FUNGINOS study analyzed clinical and mycological BTC characteristics.

METHODS

A 3-year prospective study was conducted in 567 consecutive candidemias. Species identification and antifungal susceptibility testing (CLSI) were performed in the FUNGINOS reference laboratory. Data were analyzed according to STROBE criteria.

RESULTS

43/576 (8%) BTC occurred: 37/43 (86%) on fluconazole (28 prophylaxis, median 200 mg/day). 21% BTC vs. 23% non-BTC presented severe sepsis/septic shock. Overall mortality was 34% vs. 32%. BTC was associated with gastrointestinal mucositis (multivariate OR 5.25, 95%CI 2.23-12.40, p < 0.001) and graft-versus-host-disease (6.25, 1.00-38.87, p = 0.05), immunosuppression (2.42, 1.03-5.68, p = 0.043), and parenteral nutrition (2.87, 1.44-5.71, p = 0.003). Non-albicans Candida were isolated in 58% BTC vs. 35% non-BTC (p = 0.005). 63% of 16 BTC occurring after 10-day fluconazole were non-susceptible (Candida glabrata, Candida krusei, Candida norvegensis) vs. 19% of 21 BTC (C. glabrata) following shorter exposure (7.10, 1.60-31.30, p = 0.007). Median fluconazole MIC was 4 mg/l vs. 0.25 mg/l (p < 0.001). Ten-day fluconazole exposure predicted non-susceptible BTC with 73% accuracy.

CONCLUSIONS

Outcomes of BTC and non-BTC were similar. Fluconazole non-susceptible BTC occurred in three out of four cases after prolonged low-dose prophylaxis. This implies reassessment of prophylaxis duration and rapid de-escalation of empirical therapy in BTC after short fluconazole exposure.

Liver fungal infections: an overview of the etiology and epidemiology in patients affected or not affected by oncohematologic malignancies

Fungal infections of the liver, most commonly caused by Candida spp., often occur in patients with hematologic malignancies treated with chemotherapy. Colonization of the gastrointestinal tract is thought to be the main origin of dissemination of Candida; mucositis and neutropenia facilitate the spread of Candida from the gastrointestinal tract to the liver. Hepatic involvement due to other fungi is a less common infectious complication in this setting. Fungal infections represent a less common cause of hepatic abscesses in non-oncohematologic population and the trend appears to be decreasing in recent years. Understanding of the etiology and epidemiology of fungal infections of the liver is indicated for an appropriate antimicrobial therapy and an overall optimal management of fungal liver infections.

Use of 1,3-β-D-glucan in invasive fungal diseases in hematology patients

INTRODUCTION

Invasive fungal diseases (IFD) remain a leading cause of morbidity and mortality in hematology patients. Within a diagnostic-driven approach, the use of the serum (1,3)-ß-D-glucan (BDG) test represents a valid tool for the early diagnosis and treatment of IFD. Areas covered: The available literature on the use of BDG in hematology patients was systematically retrieved. Then, it was reviewed and discussed, to identify key issues pertaining to a clinically-oriented narrative presentation of the topic. Expert commentary: The use of BDG in hematology patients at risk for invasive aspergillosis (IA) is secondary to the use of galactomannan. However, since BDG is not specific for IA, it offers an advantage of diagnosing also other IFD, such as candidiasis and pneumocystosis. The limitations of BDG include high costs and lower sensitivity in hematology patients compared to other cohorts. The risk of false positive results is possibly lower in real life than in theory, since glucan-free equipment is available and modern dialysis membranes and blood products usually do not release BDG. Thus, in experienced hands and selected clinical situations, BDG is a useful diagnostic tool, particularly due to short turnover time to results and versatility in diagnosing different IFD.

Progress in the Diagnosis of Invasive Fungal Disease in Children

PURPOSE OF REVIEW

This review summarizes the fungal diagnostic measures currently available for use in paediatric patients at high risk for developing invasive fungal disease (IFD) and those suspected of having an IFD. The clinical utility of each test is described based on reported performances of individual tests in specific paediatric populations.

RECENT FINDINGS

Available studies in the paediatric population are scarce and are characterized by a huge heterogeneity in underlying diseases (e.g. different risk for IFD), different study objectives and management strategies (screening versus diagnostic) used.

SUMMARY

A final valuation of paediatric studies on fungal diagnostic tools is limited. While the galactomannan and fungal PCR assays are useful to exclude the presence of IFD, it is unclear if mannan, mannan antibodies and β-D-glucan are of benefit due to a lack of studies or validation of the cut-off, respectively. Well-designed multicentre paediatric studies are urgently needed to improve the outcome of IFD.

First human model of in vitro Candida albicans persistence within granuloma for the reliable study of host-fungi interactions

Backgound

The balance between human innate immune system and Candida albicans virulence signaling mechanisms ultimately dictates the outcome of fungal invasiveness and its pathology. To better understand the pathophysiology and to identify fungal virulence-associated factors in the context of persistence in humans, complex models are indispensable. Although fungal virulence factors have been extensively studied in vitro and in vivo using different immune cell subsets and cell lines, it is unclear how C. albicans survives inside complex tissue granulomas.

Methodology/Principal Finding

We developed an original model of in vitro human granuloma, reproducing the natural granulomatous response to C. albicans. Persistent granulomas were obtained when the ratio of phagocytes to fungi was high. This in vitro fungal granuloma mimics natural granulomas, with infected macrophages surrounded by helper and cytotoxic T lymphocytes. A small proportion of granulomas exhibited C. albicans hyphae. Histological and time-lapse analysis showed that C. albicans blastoconidia were located within the granulomas before hyphae formation. Using staining techniques, fungal load calculations, as well as confocal and scanning electron microscopy, we describe the kinetics of fungal granuloma formation. We provide the first direct evidence that C. albicans are not eliminated by immunocompetent cells inside in vitro human granulomas. In fact, after an initial candicidal period, the remaining yeast proliferate and persist under very complex immune responses.

Conclusions/Significance

Using an original in vitro model of human fungal granuloma, we herein present the evidence that C. albicans persist and grow into immunocompetent granulomatous structures. These results will guide us towards a better understanding of fungal invasiveness and, henceforth, will also help in the development of better strategies for its control in human physiological conditions.

Infections in Leukemia and Hematopoietic Stem Cell Transplantation

Infections are one of the most common complications in patients diagnosed with leukemia and serve as a major obstacle to treatment. Through the early 1970s, infections were the most common cause of death in patients diagnosed with acute leukemia, but improvement in treatment and supportive care over the past few decades, coupled with expanded prophylaxis and prevention regimens, have led to reduction in both the frequency and severity of infections. Regardless, due in part to an aging cancer population and the diversity of cancer treatments and procedures, infectious diseases remain a major cause of morbidity and mortality in patients with leukemia.

Favorable outcome of chronic disseminated candidiasis in four pediatric patients with hematological malignancies

Four children were diagnosed with chronic disseminated candidiasis (CDC) during treatment for hematological malignancies. All presented with persistent fever, not responsive to broad-spectrum antibiotics, abdominal distension and hepatosplenomegaly. Two children needed artificial ventilation because of respiratory insufficiency. The time between onset of neutropenic fever and diagnosis of CDC ranged from 20-49 days. Ultrasound and computed tomography failed to demonstrate CDC during the neutropenic phase. All children needed a liver or spleen biopsy to establish the diagnosis of CDC. Three of four patients continued chemotherapy during treatment for the fungal infection. All patients had a favorable outcome, both in terms of the invasive Candida infections, as well as their underlying malignancies.

Wild-type Drosophila melanogaster as a model host to analyze nitrogen source dependent virulence of Candida albicans

The fungal pathogen Candida albicans is a common cause of opportunistic infections in humans. We report that wild-type Drosophila melanogaster (OrR) flies are susceptible to virulent C. albicans infections and have established experimental conditions that enable OrR flies to serve as model hosts for studying C. albicans virulence. After injection into the thorax, wild-type C. albicans cells disseminate and invade tissues throughout the fly, leading to lethality. Similar to results obtained monitoring systemic infections in mice, well-characterized cph1Δ efg1Δ and csh3Δ fungal mutants exhibit attenuated virulence in flies. Using the OrR fly host model, we assessed the virulence of C. albicans strains individually lacking functional components of the SPS sensing pathway. In response to extracellular amino acids, the plasma membrane localized SPS-sensor (Ssy1, Ptr3, and Ssy5) activates two transcription factors (Stp1 and Stp2) to differentially control two distinct modes of nitrogen acquisition (host protein catabolism and amino acid uptake, respectively). Our results indicate that a functional SPS-sensor and Stp1 controlled genes required for host protein catabolism and utilization, including the major secreted aspartyl protease SAP2, are required to establish virulent infections. By contrast, Stp2, which activates genes required for amino acid uptake, is dispensable for virulence. These results indicate that nutrient availability within infected hosts directly influences C. albicans virulence.

[The Spanish Society of Paediatric Infectious Diseases (SEIP) recommendations on the diagnosis and management of invasive candidiasis]

Candida yeasts are ubiquitous commensals, which can cause opportunistic infection in any location of the body. The source of infection may be both endogenous and exogenous. Invasive candidiasis encompasses different entities ranging from invasive candidiasis to disseminated multiorgan infection. Invasive candidiasis is the third leading cause of nosocomial bloodstream infection and the fourth of all nosocomial infections. It is also the most common invasive fungal infection in non-neutropenic critically ill patients, with a remarkable increase in the last 20 years owing to the increased survival of these patients and to more complex diagnostic, therapeutic and surgical procedures. Its incidence in infants, according to recent reviews, stands at 38.8 cases/100,000 children younger than 1 year. Candida albicans remains the most frequent isolate in invasive infections, although infections caused by other species have risen in the last years, such as C. kruzsei, C. glabrata and C. parapsilosis; the latter causing invasive candidiasis mainly associated with central venous catheter management, especially in neonatal units. The overall mortality of invasive candidiasis is high, with 30-day mortality reaching 20-44% in some series involving paediatric patients. This report provides an update on incidence, epidemiology, clinical presentation, diagnosis, treatment and outcome of invasive infection by Candida spp. in the paediatric patient.

Hospital epidemiology and infection control in acute-care settings

Health care-associated infections (HAIs) have become more common as medical care has grown more complex and patients have become more complicated. HAIs are associated with significant morbidity, mortality, and cost. Growing rates of HAIs alongside evidence suggesting that active surveillance and infection control practices can prevent HAIs led to the development of hospital epidemiology and infection control programs. The role for infection control programs has grown and continues to grow as rates of antimicrobial resistance rise and HAIs lead to increasing risks to patients and expanding health care costs. In this review, we summarize the history of the development of hospital epidemiology and infection control, common HAIs and the pathogens causing them, and the structure and role of a hospital epidemiology and infection control program.

High ferritin levels are associated with hepatosplenic candidiasis in hematopoietic stem cell transplant candidates

OBJECTIVES

Invasive fungal infections (IFI) are a significant cause of morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. Hepatosplenic candidiasis (HSC) is defined as a distinct form of invasive candidiasis, with liver, spleen, and kidney involvement, in patients with hematological disorders.

METHODS

The charts of 255 patients (male/female 168/87; median age 35 (range 16-71) years) who were evaluated pre-HSCT at the Gazi University Hospital Stem Cell Transplantation Unit between 2003 and 2008, were retrospectively reviewed.

RESULTS

HSC, which was demonstrated in six (2.3%) patients, was found to be more common in allogeneic HSCT recipients than in autologous HSCT recipients and in patients who had received two or more previous chemotherapy courses than in patients who had received fewer than two (p>0.05). Patients with HSC tended to have a worse performance status than patients without HSC according to the World Health Organization (p=0.001) and Karnofsky scale (p=0.007). Pre-transplantation ferritin (p=0.008) and acute phase reactant levels, including erythrocyte sedimentation rate (p=0.025) and C-reactive protein (p=0.007), were significantly higher in patients with HSC than in patients without HSC.

CONCLUSIONS

This study shows the predictive role of pre-transplantation ferritin levels in selecting a subset of patients at increased risk for HSC. Pre-transplantation risk assessment and targeted strategies might lower the morbidity and mortality of IFI in HSCT recipients.

Infections in pediatric patients with hematologic malignancies

Despite significant advances in supportive care, infection remains second only to malignancy as a cause of death in pediatric oncology patients, and infection accounts for a large fraction of treatment-related costs. Multiple risk factors contribute to infection-related morbidity, chief among them the immunosuppressive effects of leukemia itself and of cytotoxic chemotherapy, prolonged hospitalization and antibiotic use, and loss of barrier integrity associated with mucositis and the need for indwelling central access. While viruses are the most common causes of infection, bacteria are responsible for most life-threatening complications. Gram-negative bacilli are a concern for all patients undergoing treatment, while a subset of gram-positive organisms, particularly viridans streptococci, become significant pathogens in children receiving profoundly immunosuppressive therapy. Invasive fungal infections are also a serious risk for morbidity and mortality in this population. Availability of new antimicrobial agents has made it possible to treat infectious complications more effectively, but their availability is also leading to an increased prevalence of highly resistant pathogens. Future work in pediatric oncology will need to include measures to reduce the immunosuppressive effects of anti-cancer therapy, provide targeted treatment for infections, and better identify groups of patients at high risk for infectious complications, who may benefit from antimicrobial prophylaxis or more aggressive empirical therapy.

Invasive fungal infections in pediatric leukemia patients receiving fluconazole prophylaxis

BACKGROUND

Children with acute leukemia have increased risk for invasive fungal infections (IFI) but the role of long term antifungal prophylaxis (AFP) in morbidity and mortality of IFI is not well-known.

PROCEDURE

Medical records of 154 children with acute leukemia who received AFP with fluconazole during intensive chemotherapy were retrospectively reviewed to determine risk factors, clinical characteristics and outcome of IFI.

RESULTS

The overall incidence of IFI was 13.6%. Frequencies of proven, probable and possible infections were 7.2%, 2.6%, and 3.8%, respectively. The causative agent was Candida in 12 (57.2%) and Aspergillus in 9 (42.8%) children. There were 10 children with candidemia (47.6%), 7 with pulmonary aspergillosis (33.4%), 2 with hepatosplenic candidiasis (10.0%), one with sinopulmonary aspergillosis (4.5%) and one with sinus aspergillosis (4.5%). IFI was twice as common in acute myeloid leukemia (AML) (20.7%) than in acute lymphoblastic leukemia (ALL) (10.2%). Duration of profound neutropenia (P = 0.01) and steroid medications (P = 0.001) were significantly associated with IFI in univariate but not in multivariate analysis. Liposomal amphotericin B (L-AMB) was successful in 15 of 21 children as a single agent. Voriconazole produced complete response in four children with invasive aspergillosis and two with hepatosplenic candidiasis, who were unresponsive to L-AMB. The rate of IFI attributable death was 5%.

CONCLUSIONS

Our results indicate that AFP with fluconazole and early empirical antifungal therapy may be effective in reducing the incidence and mortality of IFI in children with acute leukemia.

Adjuvant corticosteroid therapy for chronic disseminated candidiasis

BACKGROUND

Chronic disseminated candidiasis (CDC) is typically observed during neutrophil recovery in patients with acute leukemia and requires protracted antifungal therapy.

OBJECTIVE

Our objective was to document the efficacy and tolerance of corticosteroid therapy (CST) in patients with symptomatic CDC, including those who experienced fever and abdominal pain despite ongoing antifungal therapy.

METHODS

We performed a retrospective, multicenter study involving 10 pediatric and adult patients who experienced ongoing symptomatic CDC despite receipt of appropriate antifungal therapy for whom adjuvant oral CST was initiated.

RESULTS

All cases of CDC were proven or probable, as determined on the basis of the European Organization for Research and Treatment of Cancer-Mycosis Study Group definition criteria, and occurred in patients with leukemia. CDC-attributable clinical symptoms resolved with CST, which was started a mean of 33.8 days after antifungal therapy had been initiated. Fever and abdominal pain disappeared a median of 4-5 days, and serum fibrinogen and C-reactive protein levels returned to normal values within 14-30 days. The median duration of hospitalization after CST initiation was 8.8 days. Hepatosplenic microabscesses decreased or disappeared within a mean period of 107 days (range, 30-210 days). No relapses of CDC were observed during a median duration of follow-up of 6.5 years (range, 4-9 years).

CONCLUSIONS

In children and adults who experience persistently symptomatic CDC despite ongoing receipt of antifungal therapy, CST involving a prednisone equivalent at a dosage of > or =0.5 mg/kg per day for at least 3 weeks is associated with a prompt resolution of symptoms and of inflammatory response. These findings support the pathophysiological hypothesis that CDC belongs to the spectrum of fungus-related immune reconstitution inflammatory syndrome.

Nosocomial fungal infections: epidemiology, diagnosis, and treatment

Invasive fungal infections are increasingly common in the nosocomial setting. Furthermore, because risk factors for these infections continue to increase in frequency, it is likely that nosocomial fungal infections will continue to increase in frequency in the coming decades. The predominant nosocomial fungal pathogens include Candida spp., Aspergillus spp., Mucorales, Fusarium spp., and other molds, including Scedosporium spp. These infections are difficult to diagnose and cause high morbidity and mortality despite antifungal therapy. Early initiation of effective antifungal therapy and reversal of underlying host defects remain the cornerstones of treatment for nosocomial fungal infections. In recent years, new antifungal agents have become available, resulting in a change in standard of care for many of these infections. Nevertheless, the mortality of nosocomial fungal infections remains high, and new therapeutic and preventative strategies are needed.

Effect of neutropenia and treatment delay on the response to antifungal agents in experimental disseminated candidiasis

Disseminated candidiasis is associated with a high rate of morbidity and mortality. The presence of neutrophils and the timely administration of antifungal agents are likely to be critical factors for a favorable therapeutic outcome of this syndrome. The effect of neutropenia on the temporal profile of the burden of Candida albicans in untreated mice and those treated with amphotericin B was determined using a pharmacodynamic model of disseminated candidiasis. A mathematical model was developed to describe the rate and extent of the C. albicans killing attributable to neutrophils and to amphotericin B. The consequences of a delay in the administration of amphotericin B, flucytosine, or micafungin were studied by defining dose-response relationships. Neutrophils caused a logarithmic decline in fungal burden in treated and untreated mice. The combination of amphotericin B and neutrophils resulted in a high rate of Candida killing and a sustained anti-C. albicans effect. In neutropenic mice, 5 mg/kg of body weight of amphotericin B was required to prevent progressive logarithmic growth. An increased delay in drug administration resulted in a reduction in the maximum effect to a point at which no drug effect could be observed. Neutrophils and the timely initiation of antifungal agents are critical determinants in the treatment of experimental disseminated candidiasis.

Candidaemia in patients with haematological disorders and stem cell transplant

The incidence of non-albicans species of Candida has recently increased, especially in patients with malignant haematological disorders receiving fluconazole prophylaxis. A retrospective study of patients who developed candidaemia at Riyadh Armed Forces Hospital between January 1992 and December 2002 was carried out. Thirty one episodes of candidaemia occurred in 27 patients with a variety of haematological disorders. Twenty-four episodes were caused by non-albicans species of Candida and only 7 episodes were caused by C.albicans. The most frequent underlying haematological disorders were acute myeloid leukaemia (AML) followed by acute lymphoblastic leukaemia (ALL). The main predisposing factors for the development of candidaemia were: broad spectrum antibiotics, central venous catheters, neutropenia, cytotoxic chemotherapy, coexisting bacterial infections, steroid therapy, relapsing or untreated primary disease and fluconazole prophylaxis.

Eight episodes were complicated by chronic disseminated candidiasis. Amphotericin-B and amBisome were used in the treatment of Candida infections. The treatment was successful in 86% of the episodes of C. albicans and 50% of the episodes due to nonalbicans species of Candida. The highest mortality rate was encountered with C.tropicalis infections.

Candidaemia is an important cause of mortality and morbidity in patients with malignant haematological disorders and stem cell transplant. The predominance of non-albicans species of Candida especially C.krusei and C.tropicalis is alarming. The early administration of appropriate antifungal therapy and the removal of infected intravascular catheters improve the outcome considerably.

Fungal Liver Infection in Immunocompromised Patients: Depiction with Multiphasic Contrast-enhanced Helical CT

PURPOSE

To retrospectively assess multiphasic (nonenhanced, arterial phase, and portal venous phase) computed tomography (CT) of the liver for depiction of hepatic fungal infection in immunocompromised patients.

MATERIALS AND METHODS

The institutional ethics review board approved the study and waived the requirement for informed consent. Sixty multiphasic hepatic CT examinations were performed in 39 immunocompromised patients who fulfilled the criteria for having probable or proved fungal liver infection. The detection and conspicuity of focal liver lesions were assessed on scans obtained during each CT phase. The lesion enhancement pattern was determined, and, accordingly, lesions were stratified into two groups: lesions suggestive of infection (with ring enhancement patterns or high attenuation) and nonspecific hypoattenuating lesions. Statistical analyses were performed by using logistic regression with generalized estimating equations.

RESULTS

A total of 536 liver lesions detected at 36 CT examinations with results positive for fungal infection were assessed. All 36 (100%) examinations yielded positive results during the arterial phase, whereas 25 (69%) of them yielded positive results during the portal venous phase (P < .001). At lesion-by-lesion analysis, the arterial phase scans depicted significantly more lesions (483 of 536 [90%]) than the portal venous phase (329 of 536 [61%]) and nonenhanced (265 of 465 [57%]) scans (P < .001 for both comparisons). In addition, on arterial phase scans, 386 of 483 lesions, as compared with 134 of 329 lesions on portal venous phase scans (P < .001), were judged to have an enhancement pattern suggestive of infection. The CT phases did not differ significantly in terms of the conspicuity of detected lesions.

CONCLUSION

In patients suspected of having hepatic fungal infection, arterial phase CT depicts significantly more hepatic lesions than does CT performed during the other phases, and it reveals more lesions with enhancement patterns suggestive of infection. Arterial phase CT should be performed in addition to portal venous phase CT in patients suspected of having hepatic fungal infection.

Chronic disseminated candidiasis in patients with acute leukemia: emphasis on diagnostic definition and treatment

BACKGROUND

Chronic disseminated candidiasis (CDC) is a form of invasive fungal infection that occurs most commonly in patients with acute leukemia treated with chemotherapy. Recent studies have provided evidence for diagnostic alternatives to invasive procedures and more therapeutic options for the management of this complication. In order to put diagnostic criteria and methodological approach to the disease into the perspective of developing strategies for therapy, all relevant studies published in the English literature over the last 30 years were examined.

MATERIALS AND METHODS

The English-language articles located through MEDLINE (1966 to present) and from selected bibliographies.

RESULTS

There is increased recognition of CDC as complication of treatment with chemotherapy in patients with acute leukemia. Liver biopsy may not always be revealing or feasible to perform in some patients. Among the imaging modalities, magnetic resonance imaging has obtained preeminence as a non-invasive tool for the diagnosis of hepatosplenic fungal infections. Administration of amphotericin B (Amp B) in relatively large cumulative doses is needed to ensure appropriate control of the infection and prevention of future relapse. Patients intolerant of, or refractory to conventional Amp B have been successfully salvaged using fluconazole or lipid formulations of Amp B. A constellation of clinical, laboratory and radiologic parameters should be used to determine response and efficacy of therapy. There is sufficient evidence to support the safety and feasibility of continuing chemotherapy for acute leukemia in conjunction with antifungal treatment in patients diagnosed with CDC.

CONCLUSION

The development of CDC in patients with acute leukemia does not preclude further chemotherapy or constitute contraindication for bone marrow transplantation. Knowledge of the course and pattern of evolution of the disease and adopting aggressive therapeutic approach will likely reduce the morbidity and mortality from this complication.

Candida albicans Csy1p is a nutrient sensor important for activation of amino acid uptake and hyphal morphogenesis

Candida albicans is an important human pathogen that displays a remarkable ability to detect changes in its environment and to respond appropriately by changing its cell morphology and physiology. Serum- and amino acid-based media are known to induce filamentous growth in this organism. However, the mechanism by which amino acids induce filamentation is not yet known. Here, we describe the identification and characterization of the primary amino acid sensor of C. albicans, Csy1. We show that Csy1p plays an important role in amino acid sensing and filamentation. Loss of Csy1p results in a lack of amino acid-mediated activation of amino acid transport and a lack of induction of transcription of specific amino acid permease genes. Furthermore, a csy1Delta/csy1Delta strain, lacking Csy1p, is defective in filamentation and displays altered colony morphology in serum- and amino acid-based media. These data provide the first evidence that C. albicans utilizes the amino acid sensor Csy1p to probe its environment, coordinate its nutritional requirements, and determine its morphological state.

Hospital-acquired candidemia in HIV-infected patients. Incidence, risk factors and predictors of outcome

A retrospective case-control study was performed to analyze hospital-acquired candidemia in HIV-positive patients. To understand the impact of Highly Active Antiretroviral Therapy (HAART) on the incidence of nosocomial candidemia, two time periods were compared: A (1992-1996) and B (1997-2001). 32 out of 38 (84%) cases of candidemia were hospital-related. A significant reduction in the incidence of all cases of hospital-acquired candidemia has been observed in the post-HAART in respect to pre-HAART period (0.09 episodes vs. 1.1 per 100/py). Multivariate analysis showed that the presence of central venous catheter was the only variable independently associated with the development of nosocomial candidemia. The overall mortality rate was 59%. Univariate analysis indicated three prognostic indicators: presence of concomitant opportunistic infections, isolation of non-albicans Candida species; neutropenia. Multivariate analysis of prognostic indicators showed that isolation of non-albicans Candida species is the only independent variable. Despite the use of HAART, this disease still represents a severe complication of advanced stage of AIDS.

Successful Treatment of Chronic Disseminated Candidiasis with Caspofungin and Itraconazole in a Patient with Progressive Acute Leukemia and Prolonged Neutropenia

Severe fungal infections remain a significant cause of morbidity and mortality in neutropenic patients undergoing dose-intensive chemotherapy for malignant diseases. Chronic disseminated candidiasis (CDC) is a life-threatening complication in neutropenic patients because of the lack of responsive hematopoietic precursor cells. Resolution of Candida organ lesions after hematopoietic reconstitution may take months. Here, we report the case of a 19-year-old neutropenic woman with relapsed acute myelogenous leukemia and candidiasis of liver, spleen, and kidneys. Antifungal treatment was initiated using fluconazole and caspofungin but was changed to itraconazole and caspofungin. Despite elevated C-reactive protein (CRP) levels and detectable Candida organ lesions, antileukemic therapy was restarted with interleukin 2 at the same time as antimicrobial treatment. Eight weeks after the start of interleukin therapy, CRP levels and organ lesions were decreased significantly irrespective of continuing neutropenia. This case report describes the successful treatment of CDC during neutropenia using combination antifungal therapy and suggests controlled studies to establish optimal therapeutic strategies.

Efficacy and safety of itraconazole prophylaxis for fungal infections after orthotopic liver transplantation: a prospective, randomized, double-blind study

BACKGROUND

There is significant morbidity and mortality related to fungal infections in the solid-organ transplant population.

METHODS

A prospective, randomized, double-blind, placebo-controlled, restricted sequential design trial was performed in 71 adults undergoing orthotopic liver transplantation. Patients were randomly assigned to receive either itraconazole (5.0 mg/kg orally, preoperatively, 2.5 mg/kg orally, two times a day, postoperatively) or placebo. Therapy continued for a maximum of 56 days or until patient was discharged from hospital or met a predefined endpoint. Measurements included incidence of fungal colonization, superficial or systemic fungal infections requiring systemic therapy, adverse events, and mortality rate.

RESULTS

This trial design supported the superiority of itraconazole in preventing fungal infections; nine patients in the placebo group (24%; 95% confidence interval, 0.118-0.412) and one patient in the itraconazole group (4%; 95% confidence interval, 0.001-0.204) developed fungal endpoints requiring therapy with amphotericin B (P=0.04, Fisher's exact test). At the time of enrollment, fungal colonization occurred in 40% and 37% of itraconazole and placebo patients (P=0.43), respectively. Adverse events were reported by 97% and 100% of the intraconazole and placebo groups, respectively, and one itraconazole and six placebo-group patients died within the study period. There was no relation to trial medication for serious adverse events.

CONCLUSION

Prophylaxis with itraconazole reduces fungal infections in patients undergoing orthotopic liver transplantation and is well tolerated.

The Pathophysiology and Treatment of Candida Sepsis

Sepsis can occur during disseminated candidiasis, but its pathogenesis differs from that caused by typical prokaryotic pathogens. Complex interactions between defects in host defense and "relative" virulence factors expressed by Candida lead to dissemination of the saprophyte to parenchymal organs, and subsequently to onset of multiorgan failure. This review focuses first on the pathophysiology of Candida sepsis, detailing current understanding of host-pathogen interactions. We then consider the choice of antifungal and supportive treatments.