Antifungal Prophylaxis in Severely Neutropenic Patients: How Much Fluconazole is Necessary?

Efficacy of Low-Dose Fluconazole for Primary Prophylaxis of Invasive Candida Infections in Patients With Acute Leukemia: A Double-Blind Randomized Clinical Trial

BACKGROUND

Invasive fungal infections (IFIs), particularly Candida infections, are a significant cause of morbidity and mortality in patients with acute leukemia. While fluconazole is widely used for prophylaxis, the optimal dosing regimen remains uncertain. This study aimed to evaluate the efficacy of low-dose fluconazole for primary prophylaxis against invasive Candida infections in patients with acute leukemia receiving intensive chemotherapy.

METHODS

A double-blind, randomized clinical trial was conducted with patients diagnosed with acute leukemia. Patients were assigned to receive either low-dose (150 mg/day) or standard high-dose (400 mg/day) fluconazole for primary prophylaxis against invasive Candida infections during intensive chemotherapy. The primary outcomes were the efficacy of antifungal prophylaxis and the safety profile.

RESULTS

A total of 120 patients (60 per group) were enrolled. The overall incidence of Candida infections was similar between the groups (p = 0.615). Candida colonization was higher in the low-dose fluconazole group during the first week, particularly with non-albicans Candida at oral and subaxillary sites (p < 0.001). However, by the third week, both groups showed a significant decline in colonization, with the reduction in the oral cavity being statistically significant (p = 0.03). Aspergillosis occurred in 38.3% of patients, with no significant difference between groups (p > 0.99). Adverse events were similar in both groups (p > 0.05).

CONCLUSION

Low-dose fluconazole is an effective alternative to high-dose regimens for preventing Candida infections in acute leukemia patients, with similar efficacy and safety. The rising threat of aspergillosis highlights the need for targeted prophylaxis. Further research is needed to refine strategies for high-risk patients.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT) number: IRCT20140818018842N37.

Optimizing antimicrobial prophylaxis strategies in acute leukemia patients: Assessing the efficacy of fluconazole

BACKGROUND

Acute myeloid (AML) and promyelocytic (APL) leukemia patients are at high risk for infection and mortality. While guidance for infection prevention is provided by the National Comprehensive Cancer Network (NCCN) and the American Society of Clinical Oncology (ASCO), each institution may vary in antimicrobial prophylaxis prescribing practices. The discrepancy may be explained by medication intolerance, cost, and low incidence of mold infections in leukemia patients. A recent meta-analysis demonstrated mortality benefits with the use of posaconazole, which was adopted by the NCCN. Despite known risks, it is unclear whether universal mold-active coverage is indicated for all AML and APL patients.

OBJECTIVE

To assess the incidence of breakthrough infections in AML and APL patients.

METHODS

This was a single-center, retrospective chart review of AML and APL patients receiving induction therapy at Baylor St Luke's Medical Center (BSLMC) between January 2019 and October 2021. The primary outcome assessed the incidence of breakthrough infections. Descriptive statistics were used to summarize the data.

RESULTS

A total of 55 patients were included and 54 (98%) had prolonged neutropenia with a median duration of 30 days. Five patients (9.3%) experienced breakthrough infections during induction while 21 individuals (38.9%) during the follow-up period. Aspergillus infections occurred in three patients receiving nonmold coverage compared to none on mold-active agents (p = 1.0) with no statistical difference in mortality.

CONCLUSION

Despite the majority of patients not receiving mold-active prophylaxis, nonmold-active prophylaxis may be sufficient with consideration of low aspergillosis incidence.

Combatting fungal biofilm formation by diffusive release of fluconazole from heptylamine plasma polymer coating

A drug-eluting coating applied onto biomedical devices and implants is an appropriate way to ensure that an inhibitory concentration of antimicrobial drugs is present at the device surface, thus preventing surface colonization and subsequent biofilm formation. In this study, a thin polymer coating was applied to materials, and it acted as a drug-delivery reservoir capable of surface delivery of the antifungal drug fluconazole to amounts up to 21 μg/cm². The release kinetics into aqueous solution were quantified by UV spectroscopy and conformed to the Ritger-Peppas and Korsmeyer-Peppas model. Complementary microbiological assays were used to determine effectiveness against Candida albicans attachment and biofilm formation, and against the control heptylamine plasma polymer coating without drug loading, on which substantial fungal growth occurred. Fluconazole release led to marked antifungal activity in all assays, with log 1.6 reduction in CFUs/cm². Cell viability assays and microscopy revealed that fungal cells attached to the fluconazole-loaded coating remained rounded and did not form hyphae and biofilm. Thus, in vitro screening results for fluconazole-releasing surface coatings showed efficacy in the prevention of the formation of Candida albicans biofilm.

Nystatin prophylaxis and treatment in severely immunodepressed patients

BACKGROUND

Nystatin is sometimes used prophylactically in patients with severe immunodeficiency or in the treatment of fungal infection in such patients, although its effect seems to be equivocal.

OBJECTIVES

To study whether nystatin decreases morbidity and mortality when given prophylactically or therapeutically to patients with severe immunodeficiency.

SEARCH METHODS

We searched PubMed from 1966 to 7 July 2014 and the reference lists of identified articles.

SELECTION CRITERIA

Randomised clinical trials comparing nystatin with placebo, an untreated control group, fluconazole or amphotericin B.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection and colonisation were independently extracted by both authors. A random-effects model was used unless the P value was greater than 0.10 for the test of heterogeneity.

MAIN RESULTS

We included 14 trials (1569 patients). The drugs were given prophylactically in 12 trials and as treatment in two. Eleven trials were in acute leukaemia, solid cancer, or bone marrow recipients; one in liver transplant patients; one in critically ill surgical and trauma patients; and one in AIDS patients. Nystatin was compared with placebo in three trials, with fluconazole in 10, and amphotericin B in one; the dose varied from 0.8 MIE to 72 MIE daily and was 2 mg/kg/d in a liposomal formulation. The effect of nystatin was similar to that of placebo on fungal colonisation (relative risk (RR) 0.85, 95% confidence interval (CI) 0.65 to 1.13). There was no statistically significant difference between fluconazole and nystatin on mortality (RR 0.75, 95% CI 0.54 to 1.03) whereas fluconazole was more effective in preventing invasive fungal infection (RR 0.40, 95% CI 0.17 to 0.93) and colonisation (RR 0.50, 95% CI 0.36 to 0.68). There were no proven fungal infections in a small trial that compared amphotericin B with liposomal nystatin. The results were very similar if the three studies that were not performed in cancer patients were excluded. For the 2011 and 2014 updates no additional trials were identified for inclusion.

AUTHORS' CONCLUSIONS

Nystatin cannot be recommended for prophylaxis or the treatment of Candida infections in immunodepressed patients.

Evidence-based guidelines for empirical therapy of neutropenic fever in Korea

Neutrophils play an important role in immunological function. Neutropenic patients are vulnerable to infection, and except fever is present, inflammatory reactions are scarce in many cases. Additionally, because infections can worsen rapidly, early evaluation and treatments are especially important in febrile neutropenic patients. In cases in which febrile neutropenia is anticipated due to anticancer chemotherapy, antibiotic prophylaxis can be used, based on the risk of infection. Antifungal prophylaxis may also be considered if long-term neutropenia or mucosal damage is expected. When fever is observed in patients suspected to have neutropenia, an adequate physical examination and blood and sputum cultures should be performed. Initial antibiotics should be chosen by considering the risk of complications following the infection; if the risk is low, oral antibiotics can be used. For initial intravenous antibiotics, monotherapy with a broad-spectrum antibiotic or combination therapy with two antibiotics is recommended. At 3-5 days after beginning the initial antibiotic therapy, the condition of the patient is assessed again to determine whether the fever has subsided or symptoms have worsened. If the patient's condition has improved, intravenous antibiotics can be replaced with oral antibiotics; if the condition has deteriorated, a change of antibiotics or addition of antifungal agents should be considered. If the causative microorganism is identified, initial antimicrobial or antifungal agents should be changed accordingly. When the cause is not detected, the initial agents should continue to be used until the neutrophil count recovers.

Antifungal Prophylaxis in Cancer Patients After Chemotherapy or Hematopoietic Stem-Cell Transplantation: Systematic Review and Meta-Analysis

Purpose

To evaluate the effect of antifungal prophylaxis on all-cause mortality as primary outcome, invasive fungal infections (IFIs), and adverse events. Many studies have evaluated the role of antifungal prophylaxis in cancer patients, with inconsistent conclusions.

Methods

We performed a systematic review and meta-analysis of randomized, controlled trials comparing systemic antifungals with placebo, no intervention, or other antifungal agents for prophylaxis in cancer patients after chemotherapy. The Cochrane Library, MEDLINE, conference proceedings, and references were searched. Two reviewers independently appraised the quality of trials and extracted data.

Results

Sixty-four trials met inclusion criteria. Antifungal prophylaxis decreased all-cause mortality significantly at end of follow-up compared with placebo, no treatment, or nonsystemic antifungals (relative risk [RR], 0.84; 95% CI, 0.74 to 0.95). In allogeneic hematopoietic stem-cell transplantation (HSCT) recipients, prophylaxis reduced all-cause mortality (RR, 0.62; 95% CI, 0.45 to 0.85), fungal-related mortality, and documented IFI. In acute leukemia patients, there was a significant reduction in fungal-related mortality and documented IFI, whereas the difference in mortality was only borderline significant (RR, 0.88; 95% CI, 0.74 to 1.06). Prophylaxis with itraconazole suspension reduced documented IFI when compared with fluconazole, with no difference in survival, and at the cost of more adverse events. On the basis of two studies, posaconazole prophylaxis reduced all-cause mortality (RR, 0.74; 95% CI, 0.56 to 0.98), fungal-related mortality, and IFI when compared with fluconazole.

Conclusion

Antifungal prophylaxis decreases all-cause mortality significantly in patients after chemotherapy. Antifungal prophylaxis should be administered to patients undergoing allogeneic HSCT, and should probably be administered to high-risk acute leukemia patients.

Detection of bacteria in endodontic samples by polymerase chain reaction assays and association with defined clinical signs in Italian patients

BACKGROUND/AIMS

The presence of selected bacteria (Enterococcus faecalis, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, Treponema denticola) in infected root canals was studied using polymerase chain reaction (PCR) assays, and the association of bacteria with clinical signs of endodontic disease was assessed. The null hypothesis, that no difference could be observed between clinical signs of apical periodontitis and a specific bacterial strain, was tested.

METHODS

Microbial samples were obtained from 62 teeth in 54 patients with endodontic disease. For each tooth, clinical data including patient symptoms were collected. Teeth were categorized by diagnosis as having acute apical periodontitis (AAP, teeth with clinical symptoms but no periapical radiolucency, n=22), chronic apical periodontitis (CAP, teeth with radiolucency but no clinical symptoms, n=15) or exacerbated apical periodontitis (EAP, teeth with symptoms and radiolucency, n=25). Seventy-one percent of cases were primary endodontic infections, and 29% were recurrent ('secondary') endodontic infections (failing cases). PCR assays were used to detect the presence of the selected bacteria.

RESULTS

T. denticola and E. faecalis were each detected in 15 of 62 samples (24%), P. gingivalis in 8 samples (13%), P. intermedia in 5 samples (8%), and T. forsythensis in 4 samples (7%). T. denticola was detected in 56% of teeth with EAP. E. faecalis was found in 60% of teeth with CAP and in 72% of teeth with secondary infection. Statistical analysis demonstrated an association of CAP and secondary endodontic infection with the presence of E. faecalis. (P<0.01). EAP was associated with the presence of T. denticola (P<0.01).

CONCLUSION

T. denticola was associated with symptomatic endodontic disease in the presence of apical bone resorption. E. faecalis was associated with treatment failures. We suggest that these species may play critical roles in endodontic pathology.

Infectious complications and outcomes after allogeneic hematopoietic stem cell transplantation in Korea

We reviewed 242 allogeneic hematopoietic stem cell transplantation (HSCT) recipients retrospectively over a 2-year period (January 1998-December 1999) in order to analyze the characteristics and assess the outcomes of infectious complications in patients after HSCT in Korea. Bacteria were the major pathogens before engraftment, and viral and fungal infections predominated during the post-engraftment period. Varicella zoster virus was the most common viral pathogen after engraftment. Cytomegalovirus disease occurred mainly in the late-recovery phase. The frequency of mold infection was higher than that of yeast. There was a relatively high incidence of tuberculosis (3.0%) and Pneumocystis carinii pneumonia (6.5%). One case of death by measles confirmed by autopsy was also noted. Overall, cumulative mortality was 43% (104/242), and 59.6% of these deaths (62/104) were infection-related. Allogeneic HSCT recipients from unrelated donors were prone to infectious complication and higher mortality than those from matched sibling (17/39 (43.6%) vs 45/203 (22.2%), respectively; P<0.01; odd ratio 2.5; 95% confidence interval 1.2-5.1). As infection was the main post-HSCT complication in our data, more attention should be given to the management of infections in HSCT recipients.

Nystatin prophylaxis and treatment in severely immunodepressed patients

BACKGROUND

Nystatin is sometimes used prophylactically in patients with severe immunodeficiency or in the treatment of fungal infection in such patients, although the effect seems to be equivocal.

OBJECTIVES

To study whether nystatin decreases morbidity and mortality when given prophylactically or therapeutically to patients with severe immunodeficiency.

SEARCH STRATEGY

MEDLINE and The Cochrane Library using a comprehensive search strategy, date of last search November 2001. Contacted industry and scanned reference lists.

SELECTION CRITERIA

Randomised trials comparing nystatin with placebo, an untreated control group, fluconazole or amphotericin B.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection and colonisation were extracted by both authors independently. The outcomes were weighted by the inverse variance. A random effects model was used unless p>0.10 for the test of heterogeneity.

MAIN RESULTS

We included 12 trials (1,464 patients). The drugs were given prophylactically in ten trials and as treatment in two. Seven trials were in acute leukaemia, two in cancer, one in liver transplant patients, one in critically ill surgical and trauma patients, and one in AIDS patients. Nystatin had been compared with placebo in three trials and with fluconazole in nine; the dose varied from 1.5 MIE to 72 MIE daily. The effect of nystatin was similar to that of placebo on fungal colonisation (relative risk 0.85, 95% confidence interval 0.65 to 1.13). There was no statistically significant difference between fluconazole and nystatin on mortality (relative risk 0.76, 0.49 to 1.18) whereas fluconazole was more effective in preventing invasive fungal infection (relative risk 0.37, 0.15 to 0.91) and colonisation (relative risk 0.49, 0.34 to 0.70). The results were very similar if the three studies which were not performed in cancer patients were excluded.

REVIEWER'S CONCLUSIONS

Nystatin cannot be recommended for prophylaxis or treatment of Candida infections in immunodepressed patients.

Antifungal prophylaxis during neutropenia and immunodeficiency

Fungal infections represent a major source of morbidity and mortality in patients with almost all types of immunodeficiencies. These infections may be nosocomial (aspergillosis) or community acquired (cryptococcosis), or both (candidiasis). Endemic mycoses such as histoplasmosis, coccidioidomycosis, and penicilliosis may infect many immunocompromised hosts in some geographic areas and thereby create major public health problems. With the wide availability of oral azoles, antifungal prophylactic strategies have been extensively developed. However, only a few well-designed studies involving strict criteria have been performed, mostly in patients with hematological malignancies or AIDS. In these situations, the best dose and duration of administration of the antifungal drug often remain to be determined. In high-risk neutropenic or bone marrow transplant patients, fluconazole is effective for the prevention of superficial and/or systemic candidal infections but is not always able to prolong overall survival and potentially selects less susceptible or resistant Candida spp. Primary prophylaxis against aspergillosis remains investigative. At present, no standard general recommendation for primary antifungal prophylaxis can be proposed for AIDS patients or transplant recipients. However, for persistently immunocompromised patients who previously experienced a noncandidal systemic fungal infection, prolonged suppressive antifungal therapy is often indicated to prevent a relapse. Better strategies for controlling immune deficiencies should also help to avoid some potentially life-threatening deep mycoses. When prescribing antifungal prophylaxis, physicians should be aware of the potential emergence of resistant strains, drug-drug interactions, and the cost. Well-designed, randomized, multicenter clinical trials in high-risk immunocompromised hosts are urgently needed to better define how to prevent severe invasive mycoses.