Guixia Lv

Protothecosis successfully treated with amikacin combined with tetracyclines

We report a case of protothecosis in an 18‐year‐old female student caused by Prototheca zopfii successfully treated with amikacin combined with tetracyclines.

Multiple cyp51A-based mechanisms identified in azole-resistant isolates of Aspergillus fumigatus from China

ABSTRACT Seventy-two A. fumigatus clinical isolates from China were investigated for azole resistance based on mutations of cyp51A. We identified four azole-resistant strains, among which we found three strains highly resistant to itraconazole, two of which exhibit the TR34/L98H/S297T/F495I mutation, while one carries only the TR34/L98H mutation. To our knowledge, the latter has not been found previously in China. The fourth multiazole-resistant isolate (with only moderate itraconazole resistance) carries a new G432A mutation.

A case of subcutaneous phaeohyphomycosis caused by Cladosporium cladosporioides and its treatment

Phaeohyphomycosis refers to a group of cutaneous, subcutaneous and systemic infections caused by certain dematiaceous fungi characterised by production of melanin in the mycelium. In the past decades, increasing numbers of pathogenic genera causing phaeohyphomycosis have been recognised worldwide, including mainly Exophiala, Phialophora, Cladosporium, Xylohypha, Curvularia, Dactylaria, Exserohilum, Bipolaris, Lecythophora and Alternaria. This communication reports the first case of subcutaneous phaeohyphomycosis due to Cladosporium cladosporioides in China and its pathogenic characteristics.

Cutaneous and Mucosal Phaeohyphomycosis Caused by Exophiala spinifera in a Pregnant Patient: Case Report and Literature Review

We report a case of mucocutaneous phaeohyphomycosis caused by Exophiala spinifera. Crusty plaques and nodules were major clinical features. Histological examination revealed brown yeast-like cells and hyphae. Mycological and molecular data identified E. spinifera as etiologic agent. Oral itraconazole was effective, which was in accordance with the results of in vitro susceptibility testing. We speculated that her pregnancy may play a role of risk factor in the infection by E. spinifera.

Coccidioidomycosis: Imported and possible domestic cases in China: A case report and review, 1958-2017

We report a case of imported pulmonary coccidioidomycosis caused by Coccidioides posadasii in a patient who was misdiagnosed as tuberculosis and mistreated with antituberculosis medications for 18 months. The symptoms were not relieved until antifungal treatment was started. An extensive review of the coccidioidomycosis cases occurring in China reveals 38 cases, 16 of which had no associated history of travel to any traditional endemic areas. We speculate that some factors may drive Coccidioides spp. transference to China, which then causes those domestic infections. Moreover, we indicate the first, to the best of our knowledge, possible endemic areas in China.

Successful Treatment by Surgery of a Primary Cutaneous Mucormycosis Caused by Mucor irregularis

We report a case of primary cutaneous mucormycosis caused by Mucor irregularis. A 66-year-old man was presented to our hospital with a history of gradually enlarging plaque on the right leg for about a year. The identification of pathogen based on the fungus morphology and DNA sequencing revealed M. irregularis as the responsible fungus for skin lesion. The lesion was removed incidentally by a surgery procedure, and no recrudescence was seen during a follow-up of 24-month observation.

In Vitro Analyses of Mild Heat Stress in Combination with Antifungal Agents against Aspergillus fumigatus Biofilm

ABSTRACT Aspergillus fumigatus biofilms still present a challenge for effective treatment in clinical settings. While mild heat stress has been introduced as a treatment for infectious diseases, the effectiveness of mild heat stress on A. fumigatus biofilm formation and antifungal susceptibility is still unknown. In the present study, confocal laser scanning microscopy (CLSM) was used to image and quantify Aspergillus fumigatus biofilm formation under three different regimens of continuous mild heat stress: at 37, 39, and 41°C. Furthermore, fungal growth has been investigated under the above conditions in combination with antifungal drugs (amphotericin B [AMB], micafungin [MCF], and voriconazole [VOC]) at early and late stages. CLSM analysis showed that higher temperatures induce earlier germination and greater hyphal elongation but poorer polar growth and reduced biofilm thickness. In the early stage of biofilm formation, the combination of treatment at 39 or 41°C with MCF or VOC produced no visible difference in biomass formation from similar treatments at 37°C with the same drug. Interestingly, AMB treatment at 37°C inhibited early stage biofilm formation to a much greater extent than at 39 and 41°C. At the late stage of biofilm formation, the mild heat treatments at 39 and 41°C with AMB, MCF, and VOC inhibited biomass formation compared to that at 37°C. The present data show that mild heat stress has a negative regulatory effect on biofilm formation in vitro, and antifungal drug improvement with mild heat treatment at late-stage biofilm formation provides useful indications of possible effective strategies for clinical management of aspergillosis.

Subcutaneous Phaeohyphomycosis Caused by Exophiala oligosperma in an Immunocompetent Host: Case Report and Literature Review

We report a case of subcutaneous infection caused by Exophiala oligosperma. Erythematous ulcerated plaque with exudate was major clinical features. Histopathological examination showed yeast-like cells and fungal hyphae. Mycological and molecular identification revealed E. oligosperma as etiologic agent. Local debridement and oral itraconazole were effective. To the best of our knowledge, this is the first report of phaeohyphomycosis caused by E. oligosperma in mainland China. This report highlights the potential role of E. oligosperma as an emerging cause of infection in immunocompetent patients.

The influence of the mating type on virulence of Mucor irregularis

Mucor irregularis is an emerging fungal pathogen that cause cutaneous infection and could cause death. However, little is known about its mechanism of pathogenesis. There is evidence suggesting virulence vary with mating types in fungi, including the Mucorales. Here, we characterized the mating type locus of M. irregularis and the mating type ratio of 17 clinical isolates in China. Genomic data indicated M. irregularis is heterothallic having two mating types – bearing either SexP or SexM allele. Also, we employed a mice model to study the inflammation and pathological effects of different mating types. The comparison of the inflammatory response, cytokine profiles and Th-1, Th-2 and Th-17 cells numbers in each mating type treated mice showed that the severity and disease progress were enhanced in (+) mating type treated mice. One (+/0) mutant strain, with multiple mutations at the mating locus, had defects in sexual mating ability but appeared to be more virulent than the (−) mating type. Although (+) mating type appeared to be more virulent, most of our clinical isolates presented belonged to (−) mating type. Our findings support the involvement of MAT genes in sexual fertility, and the influence of mating type on the severity of cutaneous infection.