Notwithstanding the advantages of providing definitive diagnoses, the identification of fungi based on histopathological determination can be difficult and may lead to a pit of diagnoses. Therefore, the establishment of an auxiliary diagnostic method for use in routine pathological laboratories is desirable and should improve the above situation. Our previous studies have shown the superiority of in situ hybridization (ISH) for the detection of pathogenic fungi in histological specimens. This review focuses on the usefulness of ISH in the detection and identification of pathogenic fungi from formalin-fixed and paraffin-embedded (FFPE) tissue sections, and provides an overview of ISH for the diagnosis of fungal infection and retrospective autopsy analysis using molecular procedures. Based on the above, peptide nucleic acid (PNA) probes were shown to be superior in terms of the detection of target fungi and useful since histopathological diagnosis has the potential danger of being incorrect in the identification of fungi. In conclusion, we wish to emphasize that histopathological diagnosis in combination with molecular methods such as ISH and polymerase chain reaction (PCR) of FFPE samples should enhance the accuracy of identification in relation to fungi.

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Cryptococcus neoformans is an opportunistic fungal pathogen that causes fatal meningoencephalitis in immunocompromised hosts such as patients with AIDS and hematological malignancy. Host defense to C. neoformans infection is mediated by Th1-type cellular immunity, which is triggered by host cell recognition of the pathogen-associated molecular patterns via the pattern recognition receptors. Recently, our study revealed that TLR9-dependent sensing of cryptococcal DNA was a pivotal step in initiating the host defense to this infection and raised a possibility that this process may be triggered in a distinct manner by bacterial DNA with a canonical CpG motif. In addition, we found that mice deficient in CARD9, a critical adapter molecule for signaling via C-type lectin receptors (CLRs), was highly susceptible to cryptococcal infection with impaired immune responses, suggesting a possible involvement of some CLRs. In this article, we review advances in understanding the pattern recognition and host defense response to C. neoformans, with a particular focus on our recent results.

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We assessed anti-C. albicans activities of the 4 fatty acids : caproic acid, caprylic acid, capric acid and lauric acid in vitro. All four inhibited not only the mycelial but also the yeast-form growth of Candida albicans. In particular, capric acid and caprylic acid inhibited Candida mycelia growth at very low concentrations. The effects of treatment of these two fatty acids on oral candidiasis were examined using a murine model. When 50 μl of capric acid (more than 48.8 μM) was administered three times into the oral cavity of Candida-infected mice, symptom scores of tongues of the mice were significantly improved. Histological studies of the capric acid-treated animals indicated that the fatty acid suppressed mycelial growth of the fungus on the tongue surface. These results suggest that all four fatty acids, and especially capric acid, have potential as substances supporting anti-Candida treatment.

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A 63-year-old healthy female patient presented with well defined itchy erythematous lesions on the area of her eyebrows. Her eyebrows had been tattooed two months before her visit to us. The lesions had previously been treated by application of steroid ointment and anti-histamine and steroid tablets by mouth without success. We suspected the lesions to be contact dermatitis caused by some metal element contained in the dye used for tattooing. Treatment was continued for two weeks, but the lesions spread to her cheeks and forehead. No fungal element was found from the lesions by direct microscopy at this stage. The patch-testing to 20 metal substances on her skin showed no allergic reaction. After one more week of treatment, we reexamined the scale taken from the lesions by direct microscopy, and fungal elements were found at that time. Microsporum (M.) gypseum was isolated from the scale taken from the lesions. The lesions cleared after treatment of 11 weeks' oral intake of itraconazole 100mg daily.
It was found that the patient was accustomed to sleep with her dog, a Chihuahua. On examination by a veterinarian, no skin lesions were found on the dog. We speculate that the paws of the dog might have carried soil contaminated by M. gypseum, a geophilic fungus, to the area of her eyebrows which had minor trauma after being tattooed.

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Background : T. tonsurans infection is spreading among combat sport athletes in Japan, and preventive measures are necessary.
Methods : A questionnaire survey and hairbrush-culture tests were conducted over a 4-year period on university judo athletes from about 50 university teams affiliated with the University Judo Federation of Tokyo. Culture-positive individuals were given specific treatment recommendations based on culture results and were advised to seek treatment at a medical clinic. Culture-positive individuals were re-tested at 3 months post-treatment.
Results : Approximately 65% of participants reported a history of T. tonsurans infection. The incidence of hairbrush culture-positive individuals overall gradually decreased from 11.3% (academic year 2008) to 5.4% (2011). Each year the incoming freshmen had the highest infection rate of the four academic classes. Beginning in 2009 the infection rates decreased sharply among those who had participated in the survey the previous year, and the decreases continued the following year (s) until graduation. Among culture-positive individuals, the incidence of asymptomatic carriers increased each year, from 86% in 2008 to 98% in 2011. The culture-negative conversion rate was 86% overall for those undergoing treatment.
Conclusion : Preventive measures against T. tonsurans infection in the University Judo Federation of Tokyo were successful in increasing awareness of the disease, lowering the incidence of infection, and detecting asymptomatic carriers who require treatment.

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