Deep Dermatophytosis Caused by Zoophilic Strain of Trichophyton interdigitale with Successful Treatment of Itraconazole

Prevalence and Risk Factors of Zoonotic Dermatophyte Infection in Pet Rabbits in Northern Taiwan

Dermatophytes are the group of keratinophilic fungi that cause superficial cutaneous infection, which traditionally belong to the genera Trichophyton, Microsporum, and Epidermophyton. Dermatophyte infection is not only a threat to the health of small animals, but also an important zoonotic and public health issue because of the potential transmission from animals to humans. Rabbit dermatophytosis is often clinically identified; however, limited information was found in Asia. The aims of this study are to investigate the prevalence and to evaluate the risk factors of dermatophytosis in pet rabbits in Northern Taiwan. Between March 2016 and October 2018, dander samples of pet rabbits were collected for fungal infection examination by Wood’s lamp, microscopic examination (KOH preparation), fungal culture, and PCR assay (molecular identification). Z test and Fisher’s exact test were performed to evaluate the potential risk factors, and logistic regression analysis was then performed to build the model of risk factors related to dermatophyte infection. Of the collected 250 dander samples of pet rabbits, 29 (11.6%) samples were positive for dermatophytes by molecular identification. In those samples, 28 samples were identified as the T. mentagrophytes complex and 1 sample was identified as M. canis. Based on the results of the Firth’s bias reduction logistic analyses, animal source (rabbits purchased from pet shops) and number of rearing rabbits (three rabbits or more) were shown as the main risks for dermatophyte infection in the pet rabbits in Taiwan. The results of the present study elucidate the prevalence of rabbit dermatophyte infection, pathogens, and risk factors in Taiwan, and provide an important reference for the prevention and control of rabbit dermatophytosis.

In vitro pharmacokinetics/pharmacodynamics modeling and efficacy against systemic candidiasis in Drosophila melanogaster of a bisaryloxypropanamine derivative

The number of deaths due to systemic fungal infections is increasing alarmingly, which is aggravated by the limitations of traditional treatments and multidrug resistance. Therefore, the research and development of new therapeutic options against pathogenic fungi is an urgent need. To evaluate the fungicidal activity of a synthetic compound, 1,3-bis-(3,4-dichlorophenoxy)propan-2-aminium chloride (2j), through time-kill studies and pharmacokinetics/pharmacodynamics (PK/PD) modeling. The protective effect of the compound was also evaluated using the Drosophila melanogaster minihost model of candidiasis. Mathematical modeling of time-kill data of compound 2j was performed to obtain PD characteristics. Additionally, Toll-deficient D. melanogaster flies were infected with a Candida albicans strain and treated with 2j. We observed that compound 2j demonstrated a time- and dose-dependent fungicidal effect against Candida spp. and dermatophytes, even at low concentrations, and rapidly achieved kill rates reaching the maximum effect in less than one hour. The efficacy of the compound against systemic candidiasis in D. melanogaster flies was comparable to that achieved by fluconazole. These results support the potential of compound 2j as a systemic antifungal agent candidate and serve as a starting point for further studies involving mammalian animal models.

[Trichophyton mentagrophytes-from snow leopard to man : A molecular approach for uncovering the chain of infection]

Sources of infection for Trichophyton (T.) mentagrophytes-a zoophilic dermatophyte-comprise pet rodents (guinea pigs, mice, rabbits) and sometimes cats. Human infections due to dermatophytes after contact with zoo animals, however, are extreme rare. Four zoo keepers from Basel Zoo were diagnosed to suffer from tinea manus and tinea corporis due to T. mentagrophytes. The 22-year-old daughter of one zoo keeper was also infected with tinea corporis after having worked in the snow leopard section for one day. The strain of the index patient was confirmed by a direct uniplex-PCR-EIA and sequence analysis of the ribosomal internal transcribed spacer (ITS) region (18S rRNA, ITS1, 5.8S rRNA, ITS2, 28S rRNA) as T. mentagrophytes. Three young snow leopards from Basel Zoo were identified as the origin of the fungal skin infection. The transmission occurred due to direct contact of the zoo keepers with the young snow leopards when removing hedgehog ticks (Ixodes hexagonus). Two adult snow leopards had developed focal alopecia of the facial region which was diagnosed as dermatomycoses due to T. mentagrophytes by the zoo veterinarians. By sequence analysis, both the strains from the animals and a single strain of the index patient showed 100% accordance proving transmission of T. mentagrophytes from animals to the zoo keepers. Molecular biological identification revealed a strong relationship to a strain of T. mentagrophytes from European mink (Mustela lutreola) from Finland. Treatment of patients was started using topical ointment with azole antifungals, and oral terbinafine 250 mg once daily for 4 weeks. Both adult snow leopards and the asymptomatic young animals were treated with oral itraconazole.

Majocchi's granuloma: current perspectives

Majocchi’s granuloma (MG) is a rare fungal infection of the dermis that is mainly caused by dermatophytes (in ≥95% of cases); the most frequently identified cause is anthropophilic Trichophyton rubrum. In the rest of the cases, the causes are non-dermatophytic fungi such as Aspergillus species. This review aimed to provide information about the current perspectives on MG regarding its clinical characteristics, predisposing factors, laboratory diagnosis, and treatment strategies. Although the lower extremities were reported to be the most common site of infection, facial involvement has been predominant in the past 5 years. Our literature research showed that the most common predisposing factor (55%) is the use of topical steroid creams without potassium hydroxide examination during treatment of erythematous squamous dermatoses. A reliable diagnosis of MG is based on histopathological examination, including fungal culture and molecular analyses. MG should be treated not only with topical agents but also with systemic antifungal agents that are continued until the lesions are completely resolved. In systemic treatment, the most preferred drug is terbinafine, because of its efficacy, side effects, and safety.