We present a 17-year-old Japanese male high school student, who had applied steroid ointment for atopic dermatitis, with fingernail onychomycosis due to Trichophyton tonsurans. He was found positive for T. tonsurans infection based on hairbrush culture performed due to an epidemic of T. tonsurans infection in his judo club. The hairbrush culture method is very important in screening for this infection, and dermatologists should examine the entire body of athletes who are found positive using this method. For the diagnosis of T. tonsurans infection, other than the skin and hair, the nails should also be checked by dermoscopy because the fingernail may be the origin of this fungus.
Candida species are opportunistic fungal pathogens that cause superficial or invasive infections. Recently, the incidence of infection by non-Candida albicans species, especially Candida glabrata, has increased. In this study, we analyzed the adhesion and cytotoxicity of various Candida spp. that are part of the normal human microbiota. C. albicans adheres well to cell culture plates and to cultured cells. C. glabrata selectively adheres to epithelial cells rather than to cell culture plates. Candida parapsilosis insufficiently adheres to confluent monolayers of human lung epithelial A549 and keratinocyte HaCaT cells. We then analyzed the cytotoxicity of C. albicans and C. glabrata, which adhered well to epithelial cells. C. glabrata has been found to cause more damage to A549 cells than to HaCaT cells, suggesting that resident Candida spp. have distinct cytotoxic effects in different tissues. It is important to clarify the properties of Candida spp. as there is evidence that normal microbiota can cause infections. Our data suggest that it is necessary to use appropriate cell lines for characterizing the adherence and cytotoxicity of Candida spp.
Aspergillus fumigatus is a critical human fungal pathogen that infects the host via inhalation of airborne conidia. These conidia then germinate to form filamentous hyphae, which secrete various elements to survive in the host lung. Elements such as proteins secreted by A. fumigatus can act as virulence factors in host tissues. Among secreted proteins, we were interested in the thaumatin-like proteins of A. fumigatus. In our analysis of the function of thaumatin-like proteins, we found that, like CalA and CalB, CalC has a secreted form. Originally, CalC was predicted to be a GPI-anchored protein, as documented in the Aspergillus Genome Database. Here, we report on a novel secreted form of CalC. Furthermore, we established two novel hybridomas, C103 and C306, which recognized CalC. Monoclonal antibodies produced by these hybridomas responded to recombinant CalC produced by the mammalian cell line HEK293T and to the supernatant of cultured A. fumigatus. Taken together, our data suggest that calC can be spliced to give rise to a novel secretory form of CalC, which is present in the supernatant of cultured A. fumigatus. The hybridomas that we established will be helpful in understanding the biological role of A. fumigatus CalC.
A 66-year-old woman with diabetes who was treated with prednisolone (15 mg/day) for autoimmune hepatitis developed multiple erythematous nodules with retention of purulent fluid on her lower right limb. Candida albicans was cultured from the nodules. She was started on oral fluconazole, and the lesions subsided. However, multiple dark-red abscesses and indurations newly appeared on the left crus. Histopathological examination showed numerous branched hyphae, and tissue culture yielded a Rhizopus microsporus-related fungus. She was treated with liposomal amphotericin B combined with drainage and debridement. However, she died because of poor control of the infection and hepatic disorder.
Human and animal dermatophytoses are most commonly treated with systemic antifungal drugs such as itraconazole (ITZ) and terbinafine (TRF). The antifungal susceptibility of Nannizia fulva, however, remains poorly documented. In the present study, we investigated the in vitro susceptibility of N. fulva to ITZ and TRF using the CLSI M38-A2 test. The mean MICs for the 12 tested strains were 0.6542 mg/L (range: 0.0625-1 mg/L) for ITZ and 0.15625 mg/L (range: <0.003125-0.5 mg/L) for TRF. These results indicate that ITZ and TRF at standard veterinary doses should be efficacious against N. fulva.