Effects of photodynamic therapy alone or in combination with antifungal agents on the apoptosis of planktonic and biofilm cells of Exophiala dermatitidis / 中华皮肤科杂志

Objective To evaluate the in vitro effects of photodynamic therapy alone or in combination with antifungal agents on the apoptosis of planktonic and biofilm cells of Exophiala dermatitidis (E.dermatitidis).Methods The planktonic suspensions of E.dermatitidis were prepared,and the biofilms of E.dermatitidis were prepared via a modified 96-well plate-based methods.Planktonic and biofilm cells of E.dermatitidis were separately divided into several groups:antifungal agent groups treated with antifungal agents alone,photodynamic therapy group receiving photodynamic therapy alone,combination groups receiving photodynamic therapy followed by the treatment with antifungal agents,and blank control group receiving no treatment.These antifungal agents included amphotericin B,posaconazole,voriconazole and itraconazole.The concentrations of these antifungal agents were all 1 mg/L,and the treatment with antifungal agents lasted 2 hours.Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was performed to detect the apoptosis of planktonic and biofilm cells of E.dermatitidis in all the groups.Results The antifungal agents and photodynamic therapy both affected the apoptosis of planktonic (both P ＜ 0.001) and biofilm cells (beth P ＜ 0.05) of E.dermatitidis.The apoptosis rates of E.dermatitidis planktonic cells in the control group,amphotericin B group,posaconazole group,voriconazole group and itraconazole group were 11.67％ ± 0.21％,13.30％ ± 1.78％,14.30％ ± 3.61％,14.51％ ± 1.91％and 36.17％ ± 4.00％ respectively.The apoptosis rate of E.dermatitidis planktonic cells was significantly higher in the itraconazole group than in the control group (P ＜ 0.05),but no significant differences were observed between the other 3 antifungal agent groups and control group (all P ＞ 0.05).The photodynamic therapy group also showed a significantly higher apoptosis rate of E.dermatitidis planktonic cells (41.37％ ±7.80％) compared with the control group (P ＜ 0.05).After the treatment with photodynamic therapy combined with amphotericin B,posaconazole,voriconazole or itraconazole,the apoptosis rates of E.dermatitidis planktonic cells were 29.23％ ± 6.71％,37.23％ ± 10.86％,43.57％ ± 6.42％ and 69.87％ ± 3.53％ respectively.Moreover,the photodynamic therapy + voriconazole group and photodynamic therapy + itraconazole group both showed significantly higher apoptosis rates compared with the voriconazole group and itraconazole group respectively (both P ＜ 0.05).The apoptosis rate of E.dermatitidis biofilm cells was significantly higher in the photodynamic therapy group than in the control group (32.00％ ± 0.43％ vs.25.30％ ± 1.31％,P ＜ 0.05),as well as in the photodynamic therapy + amphotericin B than in the amphotericin B group (P ＜ 0.05).Conclusion Photodynamic therapy combined with antifungal agents can markedly promote the apoptosis of planktonic and biofilm cells of E.dermatitidis.

In vitro antifungal activity of four antifungal agents alone or in combination against Exophiala dermatitidis biofilms / 中华皮肤科杂志

Objective To evaluate the in vitro antifungal activity of 4 antifungal agents alone or in combination against Exophiala dermatitidis (E.dermatitidis) biofilms.Methods E.dermatitidis biofilms were prepared by using a modified 96-well plate-based method.The in vitro antifungal activity of amphotericin B,voriconazole,itraconazole and caspofungin alone or in combination against E.dermatitidis biofilms were investigated via the broth microdilution checkerboard technique.Results The sessile minimum inhibitory concentration ranges resulting in 50％ (SMICS0) and 80％ inhibition (SMIC80) of E.dermatitidis biofilms were all ＞ 32 mg/L for itraconazole,voriconazole and caspofungin,and the SMIC50 and SMIC80 ranges of amphotericin B were 1-2 mg/L and 4-8 mg/L respectively.The combination of amphotericin B with voriconazole showed synergistic inhibitory effects against E.dermatitidis biofilms,while the combination of amphotericin B with itraconazole or caspofungin,as well as the combination of voriconazole with caspofungin,revealed no synergistic effects.No antagonistic effect was observed in any of the combinations.Conclusion Amphotericin B appears more active against E.dermatitidis biofilms,and the combination with voriconazole can enhance the anti-biofilm effects against E.dermatitidis biofilms.

In vitro antifungal activity of tacrolimus alone or in combination with itraconazole or terbinafine against Exophiala dermatitidis / 中华皮肤科杂志

Objective To evaluate in vitro antifungal activity of tacrolimus combined with itraconazole or terbinafine against Exophiala dermatitidis (E.dermatitidis).Methods The minimum inhibitory concentrations (MICs) of itraconazole and terbinafine against 12 strains of E.dermatitidis were determined using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution susceptibility method (M38-A2 Document).A broth microdilution checkerboard method was used to evaluate the in vitro antifungal activity of tacrolimus combined with itraconazole or terbinafine against E.dermatitidis.Results The MIC ranges of terbinafine and itraconazole against E.dermatitidis were 0.060-0.125 mg/L and 0.5-1 mg/L,respectively.The combination of tacrolimus with terbinafine showed synergistic inhibitory effects against 5 strains of E.dermatitidis,while the combination of tacrolimus with itraconazole revealed synergistic effects against 10 strains of E.dermatitidis.No antagonism was observed in either of the two combinations.Conclusion In vitro combination of tacrolimus with itraconazole or terbinafine can enhance the antifungal activity of itraconazole or terbinafine against E.dermatitidis.

Cutaneous phaeohyphomycosis caused by Exophiala dermatitidis: A case report and literature review.

We report a case of cutaneous phaeohyphomycosis caused by Exophiala dermatitidis. An adult male presented with a 1 month history of erythematous swelling and ulcer on the right forearm. E. dermatitidis was identifi ed from the lesion through microscopic examination, in vitro culture, cutaneous biopsy and molecular analysis. He was treated with oral itraconazole (400 mg/day) and showed improvement.

Cerebral phaeohyphomycosis by Exophiala dermatitidis.

Cerebral phaeohyphomycosis is a rare and frequently fatal disease. We report a case of cerebral phaeohyphomycosis caused by Exophiala dermatitidis in a young immuno competent male presenting to a tertiary care hospital in Jaipur.

In vitro susceptibility testing of 16 strains of Exophiala dermatitidis to 6 commonly used antifungal agents / 中华皮肤科杂志

Objective To investigate the in vitro susceptibility of 16 strains of Exophiala dermatitidis to 6 commonly used antifungal agents. Methods The Glinical and Laboratory Standards Institute (CLSI)M27-A2 protocol was carried out to determine the MIGs of terbinafine (TRB), itraconazole (ITC), amphotericin B (AMB), fluconazole (FLC), voriconazole (VRC), and caspofungin (GAS) to 16 strains of E. dermatitidis, and E-test was performed to determine those of VRG, ITC and AMB. Besides, the minimal fungicidal concentrations (MFGs) of the above antifungal agents to the 16 strains of E. dermatitidis were further assessed.The activity of TRB in combination with ITC and VRG against E. dermatitidis was also estimated. Results The MIC ranges of TRB, VRC, ITC, AMB, FLC, and CAS were 0.125 - 0.25 mg/L, 0.25 - 0.5 mg/L, 2.0 mg/L,2.0 mg/L, 16 - 32 mg/L and 16 - 64 mg/L respectively as shown by M27-A2 microdilution assay, while the MIC ranges of VRG, ITG and AMB, as determined by E-test, were 0.032 - 0.094 mg/L, 0.047 - 0.5 mg/L and 0.125 - 3.0 mg/L, respectively. The MFC ranges of TRB, VRC, ITG, AMB and FLG were 0.125 - 0.5 mg/L,0.25 - 0.5 mg/L, 2.0 - 4.0 mg/L, 2.0 - 4.0 mg/L and 16 - 64 mg/L, respectively. No synergism in the acitivity against E. dermatitidis was observed for the combination of TBR with ITC or VRC. Conclusion E. dermatitidis is susceptible to TRB, ITC, AMB, and VRC, but less sensitive to both FLC and GAS.

Therapy and Diagnosis of Phaeohyphomycosis of Central Nervons System / 实用儿科临床杂志

Objective To explore the clinical characteristics ,diagnosis, treatment and prognosis of phaeohyphomycosis. Methods Clinical data were collected, including history, physical examination, cranial and spinal imaging. Brain biopsy was performed. Data of the pathology and incubation of brain tissue were analyzed. Responsiveness to treatment was followed up. Results A previously healthy three and half years old boy was presented to our unit, with a three- month history of recurrent headache, vomiting, progressive paraplegia accompanied by urinary continence and constipation. A computed tomogram scan and magnetic resonance imaging of the brain revealed multiple lesions located in the region of the parietal - occipital lobes, periventricular area and frontal lobe, with prominent surrounding edema and irregular peripheral enhancement of the mass after the administration of contrast materials. A cerebral biopsy was performed and the pathological report was cerebral phaeohyphomycosis. The culture of the tissue and cerebrospinal fluid grew a same fungus identified as exo-phiala dermatitidis. The patient's response to therapy was poor, the parents of the boy gave up therapy, and the boy died 1 month later. Conclusions Cerebral Phaeohyphomycosis caused by Exophiala dermatitidis is rare, but the most serious form of fungus infection. Pathology and incubation of the tissue are essential for diagnosis. There is no curative therapy and the prognosis is poor.

Phaeohyphomycosis Due to Exophiala dermatitidis Successfully Treated with Itraconazole / 대한의진균학회지

Phaeohyphomycosis is a subcutaneous and systemic infection caused by dark-walled hyphae and differs from chromoblastomycosis in that it has no sclerotic cells. It commonly occurs in a immunosuppressed host. Exophiala dermatitidis, common pathogen of phaeohyphomycosis, has been commonly reported in Japan, but very rare in Korea. This report describes a case of phaeohyphomycosis due to Exophiala dermatitidis successfully treated with itraconazole.