A 28-year-old man presented at our clinic with 1-month history of an ulcer covered with crust on his left anterior tibia. Based on the morphological features and molecular identification, the patient was diagnosed as cutaneous alternariosis caused by Alternaria arborescens. He was successfully cured by oral itraconazole and topical use of 0.25% liposomal amphotericin B. A review of published studies revealed 29 cases of cutaneous alternariosis. Most cases (90%) occurred in immunosuppressed patients; itraconazole (59%) and voriconazole (24%) are the most effective treatments of choices.

This study was aimed to explain the formation mechanisms of corkscrew hairs and cigarette-ash-shaped hairs observed by dermoscopy of tinea capitis. In the present work, the ultrastructure of the involved hairs collected from a girl with tinea capitis caused by Trichophyton violaceum was observed by scanning electron microscope (SEM) and transmission electron microscope (TEM). SEM observation of the corkscrew hair revealed bent hair shaft and asymmetrically disrupted cuticle layer. TEM findings demonstrated the hair shaft became weak. The corkscrew hairs closely covered by scales on the scalp were observed under dermoscopy. We speculate that the formation of corkscrew hairs is a result of a combination of internal damage due to hair degradation by T. violaceum and external resistance due to scales covering the hair. SEM observation of the cigarette-ash-shaped hair revealed irregularly disrupted and incompact end, which might represent the stump of the broken corkscrew hair after treatment.

This chapter highlights the description of the clinical manifestation and its pathogen and the host tissue damage observed under the Scanning Electron Microscope, which helps the clinician to understand the pathogen's superstructure, the change of host subcell structure, and the laboratory workers to understand the clinical characteristics of pathogen-induced human skin lesions, to establish a two-way learning exchange database with vivid images Keywords: Fungi, "acteria, Parasite, Clinical Skin Samples, SEM . IntroductionIn dermatovereology department, skin infections by fungi, bacteria, and, parasites are very common in routine clinical practice. Differentiation and identification of these pathogens are a huge challenge and very important for the patient's diseases diagnosis and treatment. Scanning electron microscope SEM is a very strong tool for detection and observation of pathogens from the clinical samples that helps us obtain a direct proof of the pathogen on the surface of the skin samples of the lesion. "ased on the detailed morphologic image, we can recognize the ultrastructural of the pathogen and understand the pathogenesis of the skin-infected diseases. During recent years, we collected a lot of pathogenic microorganisms' photographs taken by SEM. These pathogens include fungi Trichophyton violaceum, Microsporum canis, Mucor irregularis, Lichtheimia Absidia corymbifera, Alternaria arboresce, Fon-© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. secaea pedrosoi, Aspergillus fumigatus and Malassezia , bacteria Propionibacterium acnes , and parasites Pediculosis pubis and Demodicid mites in vivo or in vitro. The diagnosis and clinical manifestation, the kinds of sample and the image of the pathogens are summarized in the . Methods"ll samples for SEM were taken from clinical patients. These samples included infected hair, scales, colony of culture, and tissue of skin biopsy. The samples for SEM were fixed in % glutar-aldehyde for h at °C , dehydrated through four gradations of alcohol solutions %, %, %, %, progressively for min each, then soaked in isoamyl acetate for min. The specimens were prepared after critical-point drying method, under which condiModern Electron Microscopy in Physical and Life Sciences 226 tion they were gilded in a vacuum chamber and observed under the SEM, FEI Inspect F , equipped with an FEG gun operated at kV at high vacuum. . Results . . Tinea capitisTinea capitis is a common superficial fungal infection of scalp hair follicles and surrounding skin. It often affects children rather than adults. Its pathogens are dermatophytes, usually species in the genera Microsporum and Trichophyton, such as Microsporum canis, Trichophyton tonsurans, and Trichophyton violaceum [ ]. The clinical manifestation of tinea capitis is highly var...