Epidemiology of Visceral Mycoses in Patients with Leukemia and MDS-Analysis of the Data in Annual of Pathological Autopsy Cases in Japan in 1989, 1993, 1997 and 2001-

Risk Factors and Clinical Characteristics of Patients with Ocular Candidiasis

Ocular candidiasis is a critical and challenging complication of candidemia. The purpose of this study was to investigate the appropriate timing for ophthalmologic examinations, risk factors for complications of ocular lesions, and their association with mortality. This retrospective cohort study applied, using multiple logistic regression analysis and Cox regression models, to cases of candidemia (age ≥ 18 years) for patients who underwent ophthalmologic consultation. Of the 108 candidemia patients who underwent ophthalmologic examination, 27 (25%) contracted patients had ocular candidiasis, and 7 experienced the more severe condition of endophthalmitis, which included subjective ocular symptoms. In most cases, the initial ophthalmologic examination was performed within one week of the onset of candidiasis with a diagnosis of ocular candidiasis, but in three cases, the findings became apparent only after a second examination within 7−14 days after onset of candidiasis. The independent risk factor extracted for the development of ocular candidiasis was the isolation of C. albicans (OR, 4.85; 95% CI, 1.58−14.90), unremoved CVC (OR, 10.40; 95% CI, 1.74−62.16), and a high βDG value (>108.2 pg/mL) (HR, 2.83; 95% CI = 1.24−6.27). Continuous ophthalmologic examination is recommended in cases of candidemia with the above risk factors with an initial examination within 7 days of onset and a second examination 7−14 days after onset.

Epidemiology of visceral mycoses in patients with acute leukemia and myelodysplastic syndrome: Analyzing the national autopsy database in Japan

Visceral mycoses (VM) are a deadly common infection in patients with acute leukemia and myelodysplastic syndrome (MDS). We retrospectively analyzed the data from the centralized "Annual Report of Autopsy Cases in Japan" that archives the national autopsy cases since 1989. Among the total of 175,615 archived autopsy cases, 7183 cases (4.1%) were acute leukemia and MDS patients. While VM was only found in 7756 cases (4.4% in total cases), we found VM had a disproportionally high prevalence among acute leukemia and MDS patients: 1562 VM cases (21.7%) and nearly sixfold higher in prevalence. Aspergillus spp. was the most predominant causative agent (45.0%), and Candida spp. was the second (22.7%) among confirmed single pathogen involved cases. The prevalence of Candida spp. infection decreased about 50% due to the widely use of fluconazole prophylaxis, which may skew toward doubling of the Mucormycetes incidence compared to 30 years ago. Complicated fungal infection (> one pathogen) was 11.0% in acute leukemia and MDS in 2015. It was 14.7 times higher than in other populations. Among 937 patients who received allogeneic hematopoietic cell transplantation (HCT), the prevalence of VM was 28.3% and 23.3% with GVHD. Aspergillus spp. was less prevalent, but Candida spp. was more associated with GVHD. Its prevalence remains stable. Although Aspergillus spp. was the primary causative agent, non-albicans Candida spp. was increasing as a breakthrough infection especially in GVHD cases. Complicated pathogen cases were more common in acute leukemia and MDS.

Detection of Mucor velutinosus in a blood culture after autologous peripheral blood stem cell transplantation : a pediatric case report

Filamentous fungi were detected in the blood culture of a one-year-old boy after autologous peripheral blood stem cell transplantation. The patient was suspected to have aspergillosis and received micafungin. Fungi were isolated on potato dextrose agar medium and incubated at 37℃ for 2-5 days. Grayish, cottony colonies formed. A slide culture showed a spherical sporangium at the tips of the sporangiophores. The fungus could have been a zygomycete. The zygomycete was isolated from three blood cultures. The antifungal drug was changed from micafungin to liposomal amphotericin B, which resulted in an improvement in the patient's symptoms. Growth was observed at 37℃, but not 42℃ in a growth temperature test. Gene sequence analysis identified the fungus as Mucor velutinosus. To the best of our knowledge, this is the first time M. velutinosus has been detected in Japan, and this case is very rare. Zygomycetes are known to be pathogens that cause fungal infections in immunodeficient patients such as those with leukemia. They are difficult to identify by culture and are identified at autopsy in many cases. Therefore, culture examinations should be performed for immunodeficient patients with the consideration of zygomycetes.

Efficacy and safety of micafungin for the prophylaxis of invasive fungal infection during neutropenia in children and adolescents undergoing allogeneic hematopoietic SCT

The objective of this study was to evaluate the efficacy and safety of micafungin for the prevention of invasive fungal infection (IFI) during the neutropenic phase of allogeneic hematopoietic SCT (allo-HSCT) in children and adolescents. This was a prospective, multicenter, open-label, single-arm study. Micafungin was administered i.v. at a dose of 1 mg/kg/day (max 50 mg) from the beginning of conditioning until neutrophil engraftment. Treatment success was defined as the absence of proven, probable, possible or suspected IFI through to 4 weeks after therapy. From April 2010 to December 2011, 155 patients were enrolled from 11 institutions in Korea, and 147 patients were analyzed. Of the 147 patients, 121 (82.3%) completed the protocol without premature interruption. Of the 132 patients in whom micafungin efficacy could be evaluated, treatment success was achieved in 119 patients (90.2%). There was no proven fungal infection in any patient. The number of patients with probable, possible and suspected IFI was two, two and nine, respectively. Thirty-five patients (23.8%) experienced 109 adverse events (AEs) possibly related to micafungin. No patients experienced grade IV AEs. Two patients (1.4%) discontinued micafungin administration due to adverse effects. None of the deaths were related to the study drug.

Gene Expression Profiling of Polymorphonuclear Leukocytes Treated with the Culture Filtrate ofAspergillus fumigatusand Gliotoxin

Pathogens of the Aspergillus species are frequently seen in deep-seated mycoses. We previously demonstrated that the culture filtrate of Aspergillus fumigatus (CF) has immunosuppressive effects on polymorphonuclear leukocytes (PMNs), which act as the main phagocytes to hyphae of Aspergillus fumigatus (A. fumigatus). But little is known about the gene expression profiles involved in it. Therefore we investigated the changes in gene expression in human PMNs treated with CF or gliotoxin at two time points, using microarray analysis. CF and gliotoxin changed the expression of 548 and 381 genes, respectively. Only 51 genes showed the same expression patterns with the two stimulants, and CF-induced changes in gene expression occurred comparatively earlier than those induced by gliotoxin. Among 31 genes encoding apoptosis, which were up- or down-regulated in this assay, only 3 genes were similarly changed by both kinds of stimulation. Apoptosis was detected and quantified using two apoptosis assays. CF and gliotoxin changed the expessions of only 3 out of 19 regulated genes related to inflammatory mediators and receptors similarly. The up-regulation of the gene encoding annexin 1 (ANXA1), which is known to be involved in extravasation and apoptosis of neutrophils, may play a role in the immunosuppressive effect of A. fumigatus. The difference in expression changes between CF and gliotoxin is presumed to be caused by the interaction among the components of CF and therefore the interaction is an area of interest for further investigation.

Epidemiology of visceral mycoses in autopsy cases in Japan: comparison of the data from 1989, 1993, 1997, 2001, 2005 and 2007 in Annual of Pathological Autopsy Cases in Japan

The data on visceral mycoses reported in the " Annual of Pathological Autopsy Cases in Japan " were analyzed epidemiologically every four years from 1989 to 2005, and in 2007. The frequency rates of visceral mycoses dropped sharply between 1989 (4.5%) and 1994 (3.2%), but by 2001 had risen again and have remained (4.4-4.6%) generally stable since then. The predominant causative agents were Candida and Aspergillus. Although the rate of candidosis showed a gradual decrease, the rate of aspergillosis showed an increase by degrees. Furthermore, the rate of aspergillosis exceeded that of candidosis in 1994, and the difference in the rates between the two conditions apparently further increased until 2001. After 2005, however no changes in this difference were observed. For complicated infections, the incidence of coinfection with Aspergillus and Candida showed a decreasing, and that with Aspergillus and Zygomycetes showed an increasing tendency. Severe infections with Zygomycetes showed a clear increase from 57.4% in 1989 to 88.9% in 2007. Comparing underlying diseases with mycoses in 1989 and 2007, leukemia (including myelodysplastic syndrome) decreased from 26.1% to 18.8% and bacterial infections (including interstitial pneumonia) increased from 11.1% to 22.1%. By age, the highest frequency rate of mycoses was observed in the range of 60-79 years, and the frequency rate of exogenous fungal infections such as aspergillosis, cryptococcosis, zygomycosis and trichosporonosis showed an increasing trend in the less than one-year old group.

Evaluation of the safety and efficacy of micafungin in Japanese patients with deep mycosis: a post-marketing survey report

The safety and efficacy of micafungin were evaluated in a Japanese post-marketing survey involving 1,142 patients with deep mycosis caused by Candida or Aspergillus. The overall clinical response was 83.0%, and the respective responses for patients with candidiasis or aspergillosis were 86.3 and 70.8%. With regard to drug reactions, 562 adverse reactions were observed in 28.5% of patients. Among the 83 serious adverse drug reactions reported by 53 patients, a causal relationship with micafungin was assessed as definite or probable for 6 reactions in 5 patients. Age and baseline hepatic and renal function status did not affect the incidence of adverse reactions, although incidence increased significantly in proportion to the severity of mycosis and daily dose (p < 0.01). In multiple logistic regression analysis, neither baseline hepatic impairment nor increased daily dose of micafungin affected the incidence of hepatobiliary disorders, however, the severity of mycosis was found to correlate significantly with hepatobiliary disorders (p = 0.031). Taken together, our post-marketing findings show that micafungin is effective against deep mycosis caused by Candida or Aspergillus in patients across a range of backgrounds.

Clinical efficacy and safety of micafungin in Japanese patients with chronic pulmonary aspergillosis: a prospective observational study

Aspergillosis has been the prevailing deep-seated mycosis in Japan since the 1990s. Although micafungin (MCFG) has been approved in Japan for the management of patients with such infections caused by Candida and Aspergillus species, there are relatively few reports on its use in patients with chronic pulmonary aspergillosis (CPA). Therefore, we conducted a prospective observational study to evaluate the efficacy and safety of the use of MCFG in Japanese patients with CPA. The efficacy of the antifungal was assessed on the basis of improvements in clinical symptoms and radiological findings. In addition, adverse events, including abnormal laboratory findings were determined. The overall clinical efficacy rate was 68.4% (26/38 patients), which is comparable to the results obtained in clinical trials for marketing approval conducted in Japan. Although adverse drug reactions were observed in six patients (15.8%), they were not serious. The most common of these reactions was abnormal liver functions. No relationship between the incidence of adverse drug reactions and age of the patients, MCFG dose, or duration of treatment was observed. Consequently, MCFG has favorable efficacy and safety profiles in Japanese CPA patients with various backgrounds.

Itraconazole for invasive fungal infection with pediatric malignancies

BACKGROUND

Invasive fungal infection (IFI) is an increasingly common and often fatal infection in children with hematological malignancies and solid tumor. Prophylactic therapy with anti-fungal agents is very important for these patients, because the early diagnosis of IFI is very difficult.

PROCEDURE

A total of 0.5 mL/kg per day of itraconazole oral solution (ITCZ-OS) was administered in twice-daily doses to 22 children with hematological malignancies who had received chemotherapy, and its usefulness and safety regarding the prevention of IFI were examined.

RESULT

Prophylactic therapy with ITCZ-OS was completed in 18 (81.8%) of the 22 children. Of these, IFI was not strongly suspected in any child. Side-effects included non-alcoholic steatohepatitis in two children, syndrome of inappropriate anti-diuretic hormone secretion in one, and liver dysfunction in one. The administration of ITCZ-OS was discontinued in these cases. These four children had received vincristine sulfate (VCR) or irinotecan hydrochloride, which were reported to interact with ITCZ. In most children the plasma levels of ITCZ were satisfactory. The plasma levels, however, were slightly increased in VCR-treated children; ITCZ should be carefully administered.

CONCLUSION

Although the number of subjects was small in the present study, the plasma concentrations of ITCZ-OS favorably increased in the children with hematological malignancies, suggesting that this agent exhibits prophylactic effects on IFI. It must be considered, however, that some combined agents cause side-effects via their interactions with ITCZ.

Histopathological study of candidal infection in the central nervous system

In recent years, incidence of invasive fungal infection has been increasing, mostly due to advances in + medicine that may produce immunocompromised individuals. Candidial infection in the central nervous system (CNS) is one of the most serious forms of blood stream infection of Candida sp. and mortality is known to be more than 50%. In this research, we employed 27 autopsies with confirmed in vasive CNS yeast infection which were confirmed. In addition to detailed morphological analysis of yeast cells in lesions, in situ hybridization was carried out with an originally designed Candida-specific peptide nucleic acid (PNA) probe to identify the candidial infection of each patient. This was followed by histopathological investigation: invasiveness, shape, and distribution of yeast or yeasts with pseudohyphal growth, and a study regarding the correlation between histological characteristics and number of leukocytes in the peripheral blood just before death. Results showed that the, supratentorial region was the most common area of disseminated candidial infection in CNS, and that density was highest in the cerebral gray matter followed by the white matter and basal ganglia. On the other hand, regarding the lesions developed in the cortical area, the average distance from the brain surface was 4.026 mm. This area corresponding to the deeper cortex has a characteristic arterial structure that refers hairpin curving reverse. The structure may contribute to the high incidence of candidial foci in the deeper cortex, because of the increase in shear stress.

Polymerase chain reaction assay for specific identification of Candida guilliermondii (Pichia guilliermondii)

The incidence rates of fungemia caused by Candida guilliermondii have been increasing over the past several years. Although still relatively rare (1.3% of all cases of fungemia in Japan), most cases of C. guilliermondii fungemia occur in patients with cancer or hematological malignancy and their mortality rate is high. As C. guilliermondii tends to be resistant to various antifungal agents, early identification of this pathogen and treatment with an appropriate antifungal agent are required to improve survival rates in these patients. However, it is extremely difficult to differentiate C. guilliermondii (Pichia guilliermondii) from members of the C. famata complex. To date, identification based on DNA sequencing has been the only reliable method for the identification of fungal groups. Here, we used a polymerase chain reaction (PCR)-based method that we developed for the simple and reliable identification of C. guilliermondii (P. guilliermondii). A pair of specific primers was designed corresponding to the 18S rDNA sequence. The PCR system was applied to isolates from fungemia patients. These yeasts could not be identified with CHROMagar Candida, but were successfully identified using this PCR-based system.

[Strategy of Aspergillus fumigatus to evade attacks from host--projectile weapons and armor]

Humans are continually inhaling environmental fungi. When the host immune system is competent, the inhaled fungi are cleared away from the lung by host defense mechanisms. But in immunocompromised individuals, the environmental fungi (e.g., Aspergillus fumigatus) sometimes cause infection. Pathogenic fungi possess various mechanisms to invade the host. A. fumigatus is no exception in possessing several virulence factors and defense mechanisms against host immune attack.One of the virulence factors is secondary metabolite. A. fumigatus produces a variety of secondary metabolites, and the fungal products in culture supernatant have a strong apoptosis-inducing activity to macrophages and alveolar epithelial cells. These data suggest that A. fumigatus is equipped with special projectile weapons for destroying host physical barriers and immunological barriers in lung.The fungal cell wall is an easy target for the host to recognize the pathogen. One of the fungal cell wall components, beta- (1,3) -glucan, is a major fungal PAMP (pathogen-associated molecular pattern), which is recognized by one of the pattern recognition receptors, dectin-1. The interaction induces activation of transcription factors and production of proinflammatory cytokines in the host cell. However, beta-glucan of A. fumigatus is strongly exposed to the surface only during the "swollen-conidia" phase. In the hyphal phase, the fungus is covered with "armor", i.e., other cell wall components to minimize the exposure of the beta-glucan structure. These findings suggest that A. fumigatus evades the recognition and the attack from host by masking beta-glucan. A. fumigatus has clever mechanisms to defend itself and to attack the host immune system.

Breakthrough disseminated zygomycosis induced massive gastrointestinal bleeding in a patient with acute myeloid leukemia receiving micafungin

A 69-year-old man, who had been receiving prednisolone for 11 months for treatment of interstitial pneumonia, was diagnosed with acute myeloid leukemia. During induction therapy, he developed severe pneumonia. Although meropenem and micafungin were started, he died of circulatory failure owing to massive gastrointestinal bleeding. Autopsy specimens obtained from the stomach revealed fungal hyphae, which had invaded diffusely into submucosal vessels and caused the massive gastric bleeding. The same hyphae were also observed in both lungs. A diagnosis of disseminated zygomycosis was confirmed by its characteristic histopathological findings. Because zygomycetes are spontaneously resistant to the newer antifungal agents, such as voriconazole or micafungin, it seems likely that the prevalence of zygomycosis as a breakthrough infection may increase in the future. Zygomycosis is a rare, but life-threatening, deep fungal infection that appears in immunologically or metabolically compromised hosts. Its manifestations are clinically similar to those of invasive aspergillosis. In addition to the well-established epidemiology of zygomycosis, this case suggests the following new characteristics. (1) Although the gastrointestinal manifestation of zygomycosis is relatively rare, it is observed more frequently than invasive aspergillosis. (2) Gastrointestinal zygomycosis occasionally leads to the development of necrotic ulcers and may induce hemorrhagic shock.(3) We should be cautious of an occurrence of breakthrough zygomycosis when we use echinocandins for patients with known risk factors, especially steroid use and neutropenia. (4) For patients who are receiving broad-spectrum antibiotics and echinocandins, who are negative for culture studies and aspergillus antigen, and who present with unresolved fever, it is important to make a prompt clinical diagnosis of zygomycosis.

[Our efforts to curb systemic fungal infections]

The number of systemic fungal infection (SFI) cases is going due to the increase in immunocompromised hosts associated with advanced chemotherapy and high-tech medical devices. Aspergillus, Candida and Cryptococcus are major etiologies of SFIs and a remarkable increase of aspergillosis has been noted. The problems of SFIs in general are lower diagnostic rate and worse prognosis compared to infections by other pathogens. Clinical concerns of SFIs are the low diagnostic rate of aspergillosis, lack of evidence for treatment of chronic aspergillosis, poor outcome of cryptococcal encephalomeningitis of immunocompromised hosts, and increasing low azole-susceptible Candida. Our final goal is to overcome these problems and to develop a newer rapid diagnostic tool for aspergillosis, establish clinical trials for chronic aspergillosis, discover new pathogenic factors of Cryptococcus and evaluate alternative treatment for low azole susceptible Candida infections. We believe research advances in these areas will be useful in the diagnosing and treatment of SFIs in the future.