Breakthrough trichosporonosis in patients receiving echinocandins: case report and literature review / 中华医学杂志(英文版)

Trichosporon species now ranks as the second most common cause of disseminated yeast infections with a high mortality rate. Breakthrough trichosporonosis in patients receiving echinocandins therapy is being recognized recently. We present a case of breakthrough trichosporonosis with acute viral myocarditis while receiving caspofungin therapy. Trichosporon infection should be considered in patients, who have risk factors for invasive fungal infection and develop unexplained clinical manifestations of infection despite treatment with echinocandins.

Environment surveillance of filamentous fungi in two tertiary care hospitals in China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Invasive fungal infections have constituted an increasingly important cause of morbidity and mortality in immunocompromised patients. In this study, a surveillance project was conducted in three different intensive care units of two large tertiary hospitals in China.</p><p><b>METHODS</b>A one-year surveillance project was conducted in two tertiary hospitals which located in northern China and southwest China respectively. Air, surfaces and tap water were sampled twice a month in a central intensive care unit, a bone marrow transplant unit, a neurosurgery intensive care unit and a live transplant department. Environmental conditions such as humidity, temperature and events taking place, for example the present of the visitors, healthcare staff and cleaning crew were also recorded at the time of sampling.</p><p><b>RESULTS</b>The air fungal load was 91.94 cfu/m(3) and 71.02 cfu/m(3) in the southwest China hospital and the northern China hospital respectively. The five most prevalent fungi collected from air and surfaces were Penicillium spp., Cladospcrium spp., Alternaria spp., Aspergillus spp. and Saccharomyces spp. in the southwest China hospital, meanwhile Penicillium spp., Fusarium spp., Aspergillus spp., Alternaria spp. and Cladospcrium spp. in the northern China hospital. The least contaminated department was intensive care units, and the heaviest contaminated department was neurosurgery intensive care unit. Seventy-three percent of all surfaces examined in the northern China hospital and eighty-six percent in the southwest China hospital yielded fungi. Fifty-four percent of water samples from the northern China hospital and forty-nine percent from the southwest China hospital yielded fungi.</p><p><b>CONCLUSIONS</b>These findings suggested that the fungus exist in the environment of the hospital including air, surface and water. Air and surface fungal load fluctuated over the year. Air fungal load was lower in winter and higher in summer and autumn, but seldom exceeded acceptable level. The higher values were created during May to August in the northern China hospital and May to June and September to October in the southwest China hospital. A correlation between air fungal load and humidity, as well as personnel was observed.</p>

Uncommon characteristics of the structure and development of Trichosporon asahii / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Trichosporon asahii (T. asahii) is one of the most important pathogenic fungus in the genus of trichosporon. Although the species identification of T. asahii was based upon the complicated results of morphologic, biochemical and biologic examination, the morphology characteristic is still the first clue to the species. Some common structures of T. asahii had been described such as arthrofilaments and arthroconidia, but other important structures of T. asahii were unclear.</p><p><b>METHODS</b>Six strains of T. asahii were incubated on the slant and micro culture of Sabouraud's dextrose agar at 30 degrees C for 7 days. Samples were fixed using 2% paraformaldehyde and 2.5% glutaraldehyde. T. asahii was observed under scanning electron microscope and transmission electron microscope.</p><p><b>RESULTS</b>The detailed characteristics of the diverse sites of germination, as well as some uncommon structures such as giant cell, sarcinate, and club-shaped macroconidia, were presented. The pseudohyphae of T. asahii were noted to produce true hyphae, either along the longitude axis or on the flank. T. asahii was noted to have blastic and thallic conidiation. Digitated branches, trichoid structures and septa inside the spores were detected.</p><p><b>CONCLUSION</b>These results may add our knowledge to the structure and development of T. asahii.</p>

Pathogenicity of Trichosporon asahii in a murine model of disseminated trichosporonosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In recent years, superficial and deep mycoses caused by trichosporon were occasionally reported. In 2001, we reported the first case of disseminated trichosporonosis caused by Trichosporon asahii (T. asahii) in China. In this study, the pathogenicity of T. asahii was investigated in a murine model of disseminated trichosporonosis.</p><p><b>METHODS</b>Seventy-five mice were randomly divided into 7 groups. Each group was inoculated with T. asahii, through intradermal, gastrointestinal tract or intravenous injection. The mice in the experimental groups were given an intraperitoneal injection of cyclophosphamide (CY) to induce granulocytopenia. Mice in the therapeutic group were given both liposomal amphotericin B and fluconazole. The main viscera of the mice were examined by means of tissue culture and pathologic sections.</p><p><b>RESULTS</b>In the two intravenous inoculation groups, T. asahii was isolated from at least one organ in 10 of the 12 granulocytopenic mice and 2 of the 14 immunocompetent mice. Two of the 7 mice in the granulocytopenia group presented with lesions in the inoculation position, but none of the 30 mice in the granulocytopenia and the control group which were inoculated intradermally or through the gastrointestinal tract had viscera infection. In the therapeutic group, the ratio of consequently dead mice, the number of involved viscera, and the incidence of systemic infection were significantly less than the untreated group. Acute purulent inflammation and granulomatous inflammation were the main pathological changes in the course of the infection. Arthrospores and filaments were found in the focus.</p><p><b>CONCLUSIONS</b>T. asahii is an opportunistic pathogen that causes cutaneous and visceral infections in immunologically impaired hosts. An immunocompetent host was to be infected by the invading T. asahii. Several organs, namely the liver, lungs, kidneys, spleen and heart, were predisposed. The therapy of combining liposomal amphotericin B with fluconazole can prevent the host from an infection and inhibit the diffusion of the infection.</p>

The surveillance and molecular epidemiology of Aspergillus in the environment and patients at liver transplant department and intensive care units / 中华皮肤科杂志

Objective To explore the possible relationship between environmental contamination by Aspergillus and invasive aspergillosis.Methods From November 2005 to October 2006,samples were collected from the environment (air in corridors,air in wards,surfaces and tap water) twice a month,and from patients (nose,pharynx and sputum) at a liver transplantation department (LTD),neurologic surgery intensive care unit (NSICU) and central intensive care unit (CICU) in our hospital,and subjected to fungal culture.The Aspergillus density was determined in these environments.The isolates of Aspergillus flavus were genotyped by random amplification of polymorphic DNA (RAPD) assay to investigate the origin of infection.Results The mean aspergillus density was 12,10.75,0 and 20 cfu/m~3 at LTD,NSICU,CICU and corridors respectively.The five most prevalent species of aspergillus in these environments in decreasing order were Aspergillus flavus,Aspergillus fumigatus,Aspergillus niger,Aspergillus versicolor and Aspergillus clavatus.RAPD demonstrated that the genotypes ofA.flavus isolated from two patients were identical to those of the environmental strains in NSICU.The A.flavus genotypes from 3 patients in CICU were all different from those of the environment strains in CICU,but the genotypes were identical from two of the three patients.Conclusions Aspergillus contamination of different degree does exist at LTD,NSICU and CICU. The genotypes of A.flavus are identical from patients and environment in NSICU,suggesting that the clinical infection may originate from hospital environment.