Fungal infections in bone marrow transplant patients

Association between fluid infusions and the recovery from acute kidney injury in patients administered liposomal amphotericin B: a nationwide observational study

Acute kidney injury (AKI) often develops during the administration of liposomal amphotericin B (L-AMB), a broad-spectrum antifungal drug. However, clinical recovery approaches for AKI patients administered L-AMB are not well established. This retrospective analysis used the data obtained from hospitals throughout Japan. AKI was defined as a ≥ 1.5-fold increase within 7 days or ≥0.3 mg/dL increase within 2 days in serum creatinine. AKI recovery was defined as a return to creatinine levels below or equal to those recorded before AKI onset. Ninety patients were assessed for recovery from AKI as per the three stages. The incidence of recovery from AKI regardless of its stage was higher, though not significant, in patients administered ≥10 mL/kg/day fluid for 7 consecutive days from AKI onset (63%) than in those who did not (35%, p = 0.053). However, if limited to AKI stage 1 patients, the former group had a significantly higher incidence of recovery (91%) than the latter group (50%, p = 0.017), even after adjusting for confounding factors (odds ratio: 10.135, 95% confidence interval: 1.148–89.513, p = 0.037). The daily fluid volume administered during the 7 consecutive days from AKI onset positively correlated with the recovery from AKI of all stages (p = 0.043). Daily consecutive fluid infusion from AKI onset may be associated with recovery from stage 1 AKI in patients administered L-AMB, with daily fluid volume positively correlating with the incidence of AKI recovery.

Efficacy of early administration of liposomal amphotericin B in patients with septic shock: A nationwide observational study

INTRODUCTION

Liposomal amphotericin B (L-AMB), a broad spectrum anti-fungicidal drug, is often administered to treat invasive fungal infections (IFIs). However, the most suitable time to initiate treatment in septic shock patients with IFI is unknown.

METHODS

Patients with septic shock treated with L-AMB were identified from the Japanese Diagnosis Procedure Combination national database and were stratified according to L-AMB treatment initiation either at septic shock onset (early L-AMB group) or after the onset (delayed L-AMB group) to determine their survival rates following septic shock onset and the shock cessation period.

RESULTS

We identified 141 patients administered L-AMB on the day of or after septic shock onset: 60 patients received early treatment, whereas 81 patients received delayed treatment. Survival rates after septic shock onset were higher in the early L-AMB group than in the delayed L-AMB group (4 weeks: 68.4% vs 57.9%, P = 0.197; 6 weeks: 62.2% vs 44.5%, P = 0.061; 12 weeks: 43.4% vs 35.0%, P = 0.168, respectively). The septic shock cessation period was shorter in the early L-AMB group than in the delayed L-AMB group (7.0 ± 7.0 days vs 16.5 ± 15.4 days, P < 0.001), with a significant difference confirmed after adjusting for confounding factors with propensity score matching (7.1 ± 7.2 days vs 16.7 ± 14.0 days, P = 0.001).

CONCLUSION

Early L-AMB administration at septic shock onset may be associated with early shock cessation.

The clinical usage of liposomal amphotericin B in patients receiving renal replacement therapy in Japan: a nationwide observational study

Background

Liposomal amphotericin B (L-AMB), a broad-spectrum antifungicidal drug, is often used to treat fungal infections. However, clinical evidence of its use in patients with renal dysfunction, especially those receiving renal replacement therapy (RRT), is limited. Therefore, we evaluated the usage and occurrence of adverse reactions during L-AMB therapy in patients undergoing RRT.

Methods

Using claims data and laboratory data, we retrospectively evaluated patients who were administered L-AMB. The presence of comorbidities, mortality rate, treatment with L-AMB and other anti-infective agents, and the incidence of adverse reactions were compared between patients receiving RRT, including continuous renal replacement therapy (CRRT) and maintenance hemodialysis (HD), and those that did not receive RRT.

Results

In total, 900 cases met the eligibility criteria: 24, 19, and 842 cases in the maintenance HD, CRRT, and non-RRT groups, respectively. Of the patients administered L-AMB, mortality at discharge was higher for those undergoing either CRRT (15/19; 79%) or maintenance HD (16/24; 67%) than for those not receiving RRT (353/842; 42%). After propensity score matching, the average daily and cumulative dose, treatment duration, and dosing interval for L-AMB were not significantly different between patients receiving and not receiving RRT. L-AMB was used as the first-line antifungal agent for patients undergoing CRRT in most cases (12/19; 63%). Although the number of subjects was limited, the incidence of adverse events did not markedly differ among the groups.

Conclusion

L-AMB may be used for patients undergoing maintenance HD or CRRT without any dosing, duration, or interval adjustments.

Factor analysis of acute kidney injury in patients administered liposomal amphotericin B in a real-world clinical setting in Japan

Liposomal amphotericin B (L-AMB) is a broad-spectrum antifungal drug that is used to treat fungal infections. However, clinical evidence of its use in patients with renal failure is limited. Here, we aimed to identify factors associated with acute kidney injury (AKI) in patients administered L-AMB. We retrospectively utilized a combination of Diagnosis Procedure Combination data and laboratory data obtained from hospitals throughout Japan between April 2008 and January 2018. In total, 507 patients administered L-AMB were identified. After L-AMB treatment initiation, AKI, which was defined as a ≥ 1.5-fold increase within 7 days or ≥ 0.3 mg/dL increase within 2 days in serum creatinine according to the KDIGO criteria, was recognized in 37% of the total patients (189/507). The stages of AKI were stage 1 in 20%, stage 2 in 11%, and stage 3 in 7%. Five factors were associated with AKI of all stages: prior treatment with angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers or carbapenem; concomitant administration of catecholamines or immunosuppressants; and ≥ 3.52 mg/kg/day of L-AMB dosing. Serum potassium < 3.5 mEq/L before L-AMB therapy was associated with severe AKI of stage 2 and 3. Altogether, these factors should be carefully considered to reduce the occurrence of AKI in patients administered L-AMB.

Management of Invasive Fungal Infections in Pediatric Acute Leukemia and the Appropriate Time for Restarting Chemotherapy

OBJECTIVE

Rapid and effective treatment of invasive fungal infection (IFI) in patients with leukemia is important for survival. In this study, we aimed to describe variations regarding clinical features, treatment modalities, time of restarting chemotherapy, and outcome in children with IFI and acute leukemia (AL).

MATERIALS AND METHODS

The charts of all pediatric AL patients in our clinic between the years of 2001 and 2013 were retrospectively reviewed. All patients received prophylactic fluconazole during the chemotherapy period.

RESULTS

IFI was identified in 25 (14%) of 174 AL patients. Most of them were in the consolidation phase of chemotherapy and the patients had severe neutropenia. The median time between leukemia diagnosis and definition of IFI was 122 days. Twenty-four patients had pulmonary IFI. The most frequent finding on computed tomography was typical parenchymal nodules. The episodes were defined as proven in 4 (16%) patients, probable in 7 (28%) patients, and possible in 14 (56%) patients. The median time for discontinuation of chemotherapy was 27 days. IFI was treated successfully in all patients with voriconazole, amphotericin B, caspofungin, or posaconazole alone or in combination. Chemotherapy was restarted in 50% of the patients safely within 4 weeks and none of those patients experienced reactivation of IFI. All of them were given secondary prophylaxis. The median time for antifungal treatment and for secondary prophylaxis was 26 and 90 days, respectively. None of the patients died due to IFI.

CONCLUSION

Our data show that rapid and effective antifungal therapy with rational treatment modalities may decrease the incidence of death and that restarting chemotherapy within several weeks may be safe in children with AL and IFI.

Experimental methodologies and evaluations of computer-aided drug design methodologies applied to a series of 2-aminothiophene derivatives with antifungal activities

Fifty 2-[(arylidene)amino]-4,5-cycloalkyl[b]thiophene-3-carbonitrile derivatives were screened for their in vitro antifungal activities against Candida krusei and Cryptococcus neoformans. Based on experimentally determined minimum inhibitory concentration (MIC) values, we conducted computer-aided drug design studies [molecular modelling, chemometric tools (CPCA, PCA, PLS) and QSAR-3D] that enable the prediction of three-dimensional structural characteristics that influence the antifungal activities of these derivatives. These predictions provide direction with regard to the syntheses of new derivatives with improved biological activities, which can be used as therapeutic alternatives for the treatment of fungal infections.

Neurological complications of hematopoietic stem cell transplantation (HSCT): a retrospective study in a HSCT center in Brazil

We present the neurological complications evaluated in a series of 1000 patients who underwent hematopoietic stem cell transplantation (HSCT). Central nervous system (CNS) neurological complications, particularly brain hemorrhages, were the most common, followed by seizures and CNS infections. An unusual neurological complication was Wernicke's encephalopathy. Less frequent neurological complications were metabolic encephalopathy, neuroleptic malignant syndrome, reversible posterior leukoencephalopathy syndrome, brain infarct and movement disorders. The most common neurological complication of the peripheral nervous system was herpes zoster radiculopathy, while peripheral neuropathies, inflammatory myopathy and myotonia were very rarely found.

Distinct responses of human monocyte subsets to Aspergillus fumigatus conidia

Aspergillus fumigatus is an environmental fungus that causes life-threatening infections in neutropenic patients. In the absence of intact innate immunity, inhaled A. fumigatus spores (conidia) germinate in the lung, forming hyphae that invade blood vessels and disseminate to other tissues. Although macrophages and neutrophils are postulated to provide defense against invasive fungal infection, animal models and human studies suggest that circulating monocytes also contribute to antifungal immunity. Although human monocyte subsets, defined as either CD14(+)CD16(-) or CD14(+)CD16(+), have been extensively characterized, their respective roles during fungal infection remain undefined. We isolated CD14(+)CD16(-) and CD14(+)CD16(+) monocytes from healthy allogeneic hematopoietic stem cell transplantation donors and compared their ability to phagocytose and inhibit A. fumigatus conidia. Both monocyte subsets efficiently phagocytose conidia, but only CD14(+)CD16(-) monocytes inhibit conidial germination yet secrete little TNF. In contrast CD14(+)CD16(+) do not inhibit conidial germination and secrete large amounts of TNF. Although CD14(+)CD16(-) and CD14(+)CD16(+) monocytes differ in their response to dormant conidia, responses are similar if conidia are already germinated at the time of monocyte uptake. Our study demonstrates that functional CD14(+)CD16(-) and CD14(+)CD16(+) monocytes can be isolated from allogeneic hematopoietic stem cell transplantation donors and that these subsets differ in their response to A. fumigatus conidia.

Proinflammatory response of immature human dendritic cells is mediated by dectin-1 after exposure to Aspergillus fumigatus germ tubes

BACKGROUND

Invasive fungal infections caused by Aspergillus fumigatus represent a great challenge for immunocompromised patients. Pathogen detection is mediated by different receptors, including Toll-like receptors (TLRs), C-type lectins, and pentraxines. However, little is known about their relevance for immature human dendritic cells (iDCs).

METHODS

The gene expression pattern of iDCs after exposure to A. fumigatus germ tubes was studied by use of whole genome microarray analysis and real-time polymerase chain reaction. Fungal receptors were targeted by means of short interfering RNAs (siRNAs), which were used to knock down expression of TLR2, TLR4, DC-SIGN (dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin), PTX3 (pentraxin-related gene), dectin-1 (C-type lectin domain family 7, member A), and CARD9 (caspase recruitment domain family, member 9).

RESULTS

Exposure to A. fumigatus induced expression of cytokines, chemokines, costimulatory molecules, and genes involved in prostaglandin synthesis, as well as genes related to fungal recognition and phagocytosis. Silencing of dectin-1 resulted in reduced expression of proinflammatory cytokines (tumor necrosis factor-alpha and interleukin-12), which was also reduced by anti-Dectin-1 antibody treatment prior to exposure to A. fumigatus, zymosan, or Candida albicans.

CONCLUSION

Dectin-1 was identified as an important receptor for A. fumigatus and C. albicans on human iDCs and was found to be involved in the induction of a proinflammatory cytokine response.

Antimicrobial effects of liquid anesthetic isoflurane on Candida albicans

Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections is associated with its morphological shift such that the hyphal morphology of the fungus is most invasive. Of importance, aberrant multiplication of Candida yeast is also associated with the pathogenesis of certain mucosal diseases. In this study, we assessed the anti-candidal activity of the volatile anesthetic isoflurane in liquid form in comparison with the anti-fungal agent amphotericin B in an in vitro culture system. Exposure of C. albicans to isoflurane (0.3% volume/volume and above) inhibited multiplication of yeast as well as formation of hyphae. These data suggest development of potential topical application of isoflurane for controlling a series of cutaneous and genital infections associated with this fungus. Elucidiation of the mechanism by which isoflurane effects fungal growth could offer therapeutic potential for certain systemic fungal infections.

Synthesis and antifungal activity of a novel series of alkyldimethylamine cyanoboranes and their derivatives

A series of new amine cyanoborane derivatives were synthesized and exhibited antifungal activity. A long alkyl chain attached to the nitrogen of the amine cyanoboranes and carboxyboranes enhances antifungal activity. An enhanced activity was also obtained upon the halogenation of the amine cyanoboranes as well as in the presence of C=C double bond at the end of the N-alkyl group. The lead compounds were dimethylundecylamine cyanoborane (C11H23N(CH3)2BH2CN), 9, and its dibromo derivative dimethylundecylamine dibromocyanoborane (C11H23N(CH3)2BBr2CN), 11. The MIC values for the lead compounds against the most important human pathogenic fungi ranged from 16.25 to 32.5 micromol/L and from 10.05 to 79 micromol/L, respectively. Both compounds were found to be relatively safe in intravenous injections to mice, (MTD = 121.9 and 73.1 micromol/kg, respectively) and active against strains that are resistant to fluconazole (a conventional antifungal medicine). These data indicate their potential to become antifungal agents.

Transplant-related immunosuppression: a review of immunosuppression and pulmonary infections

Solid organ and hematopoietic stem cell transplantation are definitive therapies for a variety of end-stage diseases. Immunosuppression has improved graft survival but leaves the patient susceptible to infectious complications. Of these, pulmonary infections are the leading cause of morbidity and mortality in the transplant recipient. Allograft rejection is mediated primarily by T cells, with B cells playing a role via antibody production. Depending on the transplant type, rejection can be hyperacute, acute, or chronic. Hyperacute rejection occurs as an immediate response to preformed antibodies to donor human leukocyte antigens. Acute cellular rejection involves recipient T-cell recognition of human leukocyte antigen molecules expressed on donor-derived, antigen-presenting cells (direct allorecognition) or presentation of donor-derived peptides by recipient antigen-presenting cells to recipient T cells (indirect allorecognition). Once the alloantigens are recognized as foreign, the activation, proliferation, and production of cytokines by T lymphocytes and other immune cells lead to the amplification of the alloimmune response. This complex process involves the generation of effector T cells, antibody production by activated B cells, and macrophage activation. Alloimmunity is facilitated by the production of many cytokines, chemokines, and other effector molecules, such as complement. The immunosuppressants involve many classes of drugs, including antibody therapies that eliminate specific groups of cells or alter signaling pathways used by effector cells. The article reviews the agents and associated infections.

Risks and outcomes of invasive fungal infections in pediatric patients undergoing allogeneic hematopoietic cell transplantation

Invasive fungal infections (IFI) are the leading cause of infectious mortality in adult patients undergoing hematopoietic cell transplantation (HCT) after myeloablative conditioning, but the extent of this problem in the pediatric population is unclear. We retrospectively examined risk factors for IFI among 120 consecutive pediatric patients undergoing allogeneic HCT at a single center. The incidence of proven or probable IFI in pediatric patients during the first year after allogeneic HCT was 13%, comparable to the rate reported in adult patients; however, unlike IFI in adult patients, the majority of IFI in children occurred within the first month after transplantation. The primary risk factors for IFI were duration of neutropenia, age greater than 10 years, transplant for severe aplastic anemia or Fanconi anemia, and high-dose corticosteroid administration for 10 days or longer. IFI were more likely to be successfully treated (42%, 5/12 patients) in pediatric HCT recipients when compared to previous reports of adult recipients. Nonrelapse mortality was estimated at 17% (20/120 patients) after allogeneic HCT, of which 35% (seven patients) were directly attributed to IFI. Thus, IFI is a significant cause of nonrelapse mortality in children undergoing allogeneic HCT and more effective strategies are needed to prevent and treat IFI.

A safety evaluation of drotrecogin alfa (activated) in hematopoietic stem cell transplant patients with severe sepsis: lessons in clinical research

We conducted an open-label, multicenter, single-arm clinical trial to investigate the safety and efficacy of drotrecogin alfa (activated) (Drot AA) in hematopoietic stem cell transplant (HSCT) patients with severe sepsis. Drot AA was administered as a continuous i.v. infusion of 24 microg/kg/h for 96 h. The target enrollment was 250 patients in 15-20 transplant centers over a 2-year period (March 2003-March 2005). However, after only 10 months, in December 2003, the trial was stopped due to a low enrollment of seven patients at three of the 15 sites that were open for accrual. Six of the seven patients completed the drug infusion. Two patients experienced serious bleeding events. The first patient developed a nonfatal diffuse alveolar hemorrhage 2 days after study-drug completion. The second patient had severe coagulopathy and developed a fatal intracranial hemorrhage on the third day of drug infusion. Three of the seven patients were alive 100 days after the HSCT. The slow enrollment rate was attributed to changes in transplant preparatory regimens, enhancements in antimicrobial prophylactic protocols and the use of antimicrobial-coated catheters. The small number of patients in this report precludes a definitive assessment of the safety and efficacy of Drot AA in HSCT patients.