医学微生物学--第34章 主要病原性真菌 ppt课件

2018/7/28,医学微生物学,皮肤癣菌(Dermatophytes) 主要侵犯角化的皮肤、毛发和指（趾） 甲等浅部感染的真菌。引起皮肤癣病，包括手癣、足癣、甲癣、头癣、体癣等。包括表皮癣菌属、毛癣菌属、 和小孢子菌属三个属。,第34章 主要病原性真菌,体癣（Tinea corporis） ：环行红斑， 边界水泡， 搔痒,Skin scrapings taken from patients in 10% KOH, and show hyphae under microscope. fungiqual-a.de,Reverse side of 红色毛癣菌（T. rubrum） colony, showing deep red pigment www.hudlegekontoret.no,Typical cigar shaped macroconidia of T. rubrum granular type. 2006 The University of Adelaide,White, cottony surface,股癣（Tinea cruris）: “jock itch” infection of the groin, perianal area.(T rubrum is most frequently responsible),指甲癣（Tinea unguium）: infection on the nails that thickened, crumbling and discolored. nails can be clipped and used for culture.,Onychomycosis caused by Trichophyton rubrum. (From Hay RJ: Cutaneous and subcutaneous mycoses. In Anaissie EJ, McGinnis MR, Pfaller MA, editors: Clinical mycology, New York, 2003, Churchill Livingstone.),2018/7/28,医学微生物学,糠秕bi马拉色菌引起的花斑癣Pityriasis (tinea) versicolor Typical depigmented lesions seen in dark-skinned individuals, for example in Australian Aborigines.(Pathogen: Malassezia furfur) 2006 The University of Adelaide,角层癣菌,Treatment: Local antifungal cream (咪康唑 miconazole) or oral伊曲康唑 itraconazole are effective.Prevention: 保持皮肤干燥， 远离患者及患病动物,2018/7/28,医学微生物学,此类真菌一般存在于土壤和植物，经创伤部位侵入人体皮下组织。 一般只限局部， 也可引起深部感染。 包括: 申克孢子丝菌,第二节 皮下感染真菌,Classic lymphocutaneous form of sporotrichosis demonstrating a chain of subcutaneous nodules along the lymphatic drainage of the arm. (From Chandler FW, Watts JC: Pathologic diagnosis of fungal infections, Chicago, 1987, ASCP Press. Copyright 1987, American Society of Clinical Pathologists.),申克孢子丝菌可引起孢子丝菌病 也可引起深部感染。,2018/7/28,医学微生物学,Sporothrix schenckii on Sabourauds dextrose agar grown at 25oC colonies are moist and glabrous, with a wrinkled and folded surface. Pigmentation may vary from white to cream to black. 2006 The University of Adelaide,Microscopic morphology of the mycelial form of Sporothrix schenckii when grown on Sabourauds dextrose agar at 25oC. Note clusters of ovoid conidia（分生孢子） produced sympodially on short conidiophores arising at right angles from the thin septate hyphae.,2018/7/28,医学微生物学,治疗: 口服饱和KI溶液, 伊曲康唑Prevention: Avoid skin lesion.,一、 白假丝酵母菌在免疫力低下、菌群失调等情况下念珠菌可引起皮肤黏膜、内脏、中枢神经等各个部位的感染，称为念珠菌病，如鹅口疮、呼吸道炎症等。,第三节 机会致病性真菌 一般属机体正常菌群或广泛分布于土壤、水、空气中。,一 生物学性状 1 革兰氏阳性，圆形或卵圆形，以出芽方式繁殖 2 培养特性，普通培养基生长良好，类酵母型菌落。,C. albicans, Gram stain positive www.fnplzen.cz/mykoatlas/kvasinky/C_albicans_mi_gram_1b.jpg,C. albicans on Sabourauds dextrose agar showing typical cream coloured, smooth surfaced, waxy colonies.25oC,二 致病性：在免疫力低下、菌群失调时， 1. 皮肤黏膜感染: 可发生于皮肤的潮湿及皱褶部位。鹅口疮 (多见于艾滋病患者，体质虚弱的婴幼儿)。,2. 内脏及中枢神经系统感染,三 微生物学检查 1 直接镜检 2 分离培养与鉴定,芽管Germ-tubesproduced in serum for 3 hrs at 37oC,厚膜孢子Chlamydoconidia on Difco chlamydospore agar. Trypan blue in the medium is absorbed strongly by these terminal vesicles. Numerous small blastoconidia and pseudohyphae are also present. 2006 The University of Adelaide,2018/7/28,医学微生物学,防治原则:去除危险因素，酮康唑。,二、 新生隐球菌,新生隐球菌存在于人体表，口腔及粪便， 也大量存在于干燥的鸽粪中，通过呼吸道感染人类，引起隐球菌病 一 生物学性状1 形态与结构酵母样 菌体外有肥厚的荚膜菌体常有出芽,C. neoformans Image courtesy of Jennifer Lodge,二 致病性 传染源：鸽粪 传播途径：呼吸道 该菌为条件感染，发生于肺部，能自愈，严重者可爆发型感染，血行播散，致中枢神经系统， 导致死亡。,The ecological niches of C. neoformans are pigeon and chicken droppings. But they are not infected. The portal of entry is the respiratory system, then disseminate to other parts of the body but preferentially to the CNS, causing meningoencephalitis. No human to human transmission,Histopathology of lung shows widened alveolar septum containing a few inflammatory cells and numerous yeasts of C.neoformans. The inner layer of the yeast capsule stains red. CDC/Dr. Edwin P. Ewing, Jr.,2018/7/28,医学微生物学,MRI scans showing multiple cryptococcomas white masses in the brain. (Courtesy Prof. Tania Sorrell, Sydney NSW).,三 微生物学检查 1 直接镜检，墨汁负染 2 分离培养与鉴定 3 抗原检查 4 动物实验 四 防治鸽粪管理，抗真菌药物治疗,C. neoformans Image courtesy of Jennifer Lodge,三、 曲霉（Aspergillus）广泛分布于自然界，引起的疾病包括肺曲霉病（真菌球型肺曲霉病、曲霉肺炎、过敏性支气管肺曲霉病）、全身性曲霉病、毒素中毒、致癌(黄曲霉毒素能诱导肝癌发生)。无有效的预防措施，治疗可采用唑类抗真菌药物。,2018/7/28,医学微生物学,Aspergilloma(fungal ball) found at post-mortem in the lung of a child with leukaemia. 2006 The University of Adelaide,四、 毛霉广泛存在于自然界的腐生菌，常引起食物发生霉变，是一种条件感染性真菌，感染多发于鼻及耳部，引起坏死性炎症和肉芽肿，可扩散至全身，引起死亡。,Mucor rot on peach Photo courtesy Agriculture & A