主要致病性真菌.ppt

《主要致病性真菌.ppt》由会员分享，可在线阅读，更多相关《主要致病性真菌.ppt（81页珍藏版）》请在淘文阁 - 分享文档赚钱的网站上搜索。

1、主要致病性真菌主要致病性真菌浅部感染真菌浅部感染真菌n表面感染真菌n皮肤癣真菌皮肤癣真菌n皮下组织真菌感染2 2PityriasisversicolorshowinghyperpigmentedlesionsinaCaucasianandhyphopigmentedlesionsinanAustralianAborigine6 6Culture of Malassezia furfur on Dixons agar(contains glycerol mono-oleate)7 7Piedraia hortae(何德毛结节菌何德毛结节菌)n nIt usually affected the s

2、calp hairn nThe nodules are darker in color,harder,and more firmly attached to the hairsn nBlack Piedra8 8Piedraia hortaeformsahardsuperficialpigmentednodulearoundthehairshaft(在毛干上形成硬的黑色结节，如沙粒状)9 9Fungal otitis externan nFungal infection of the external auditory canaln nCaused by several species of

3、Aspergillus(most often A.niger),but Candida albicans is also capable of infecting this siten nThe major symptoms are itching and feeling of fullness in ear10101111皮肤癣真菌皮肤癣真菌n n引起皮肤浅部感染n n皮肤癣是人类最多见的真菌病n n统称：皮肤癣菌，大约40多个种，分属于3个属n n嗜角质蛋白，37不能生长，侵犯部位：角化的表皮，毛发，指（趾）甲n n病理变化：由真菌增殖及代谢产物刺激宿 主引起1212致病性 指（趾）甲指（

4、趾）甲 皮肤皮肤 毛发毛发毛癣菌属毛癣菌属 +表皮癣菌属表皮癣菌属 +-+-小孢子癣菌属小孢子癣菌属 -+-+一种皮肤癣菌可在不同部位引起病变相同部位的病变也可由不同的皮肤癣菌引起13131414TineapediscausedbyT.rubrum.Sub-clinicalinfection(left)showingmildmacerationunderthelittletoeandmoresevereinfection(right)showingextensivemacerationofalltoewebspacesTineaistransmittedviathefeetbydesquama

5、tedskinscalesinsubstrateslikecarpetandmatting.1515手足癣治疗原则n n水疱型温和搽剂和霜剂水疱型温和搽剂和霜剂n n角化过度型先角质剥脱剂，再用抗真角化过度型先角质剥脱剂，再用抗真菌霜剂菌霜剂n n浸渍糜烂型粉剂收干，抗继发感染，浸渍糜烂型粉剂收干，抗继发感染，再温和抗真菌再温和抗真菌1616Tinea Unguiumn nusually caused by Trichophyton sp1717甲癣治疗原则n n局部治疗甲涂剂局部治疗甲涂剂n n系统治疗伊曲康唑，特比萘芬等系统治疗伊曲康唑，特比萘芬等n n联合治疗配合拔甲或削甲治疗联合治疗配

6、合拔甲或削甲治疗1818Tinea Corporis:caused by caused by M.canisM.canis,following contact with infectious kittensfollowing contact with infectious kittens 1919 Tinea Cruris(Jock itch):Infection of the groin,mainly seen in menInfection of the groin,mainly seen in men2020Tinea Capitis(scalp ringworm)Tinea favos

7、a发内孢子发内孢子2121Tinea Capitis(scalp ringworm)Tinea alba发外孢子发外孢子2222Tinea Capitis(scalp ringworm)脓脓癣癣2323头癣治疗原则n n剪发剪发n n洗发洗发n n搽药搽药n n服药服药n n消毒消毒2424Candidiasis of skin,mucous membranes and nailsn n Predisposing factorsInfancy,pregnancy,old ageInfancy,pregnancy,old ageDisorders of immune function,e.g.,

8、leukemia,Disorders of immune function,e.g.,leukemia,corticosteroid therapycorticosteroid therapyChemotherapy,e.g.,immunosuppressive,Chemotherapy,e.g.,immunosuppressive,antibioticantibioticEndocrine disease,e.g.,diabetes mellitusEndocrine disease,e.g.,diabetes mellitusCarcinomaCarcinoma2525念珠菌性间擦疹念珠菌

9、性间擦疹好发部位：腋窝、乳房下、好发部位：腋窝、乳房下、腹股沟、会阴，多见于婴儿腹股沟、会阴，多见于婴儿及肥胖者。及肥胖者。2626n nCutaneouscandidiasis:includingCutaneouscandidiasis:includingInterdigitalcandidiasisInterdigitalcandidiasis,diapercandidiasis,paronychiaandonychomycosisdiapercandidiasis,paronychiaandonychomycosisn nVulvovaginalcandidiasisandbalanit

10、isVulvovaginalcandidiasisandbalanitisInterdigital candidiasis Candidiaonychomycosisandparonychia2727n nOropharyngealcandidiasis:includingthrush,glossitis,stomatitisandangularcheilitisOralthrush2828皮下组织真菌感染皮下组织真菌感染n n主要有孢子丝菌和着色真菌n n申克孢子丝菌，属腐生性真菌，常因外伤接触带菌的花草等引起感染。此菌可引起孢子丝菌下疳。此菌也可引起深部感染。是一种二相性真菌。n n着色真

11、菌感染发生在暴露部位，称着色真菌病。我国主要有卡氏枝孢霉和裴氏着色芽生菌。2929Sporotrichosis此菌可经微小损伤侵入皮肤，然后沿淋巴管分布，引此菌可经微小损伤侵入皮肤，然后沿淋巴管分布，引起亚急性或慢性肉芽肿，使淋巴管形成链状硬结，称起亚急性或慢性肉芽肿，使淋巴管形成链状硬结，称为孢子丝菌下疳。为孢子丝菌下疳。3030n nChromomycosisn nInfections occur in exposed areas,skin lesions become dark,so called chromomycosisn nRepresentive species:Cladospo

12、rium carrianii,Fonsecaea pedrosoi,etc.n nAre saprophytic fungi,usually enters the body by trauma3131n n经外伤侵入n n丘疹n n结节n n结节融合成疣状或菜花状n n斑痕形成影响淋巴回流n n肢体象皮肿3232ChromomycosisChronicverrucouschromoblastomycosisofthehandduetoCladophialophora carrionii3333Mycetoma 足分枝菌病足分枝菌病n n是由多种放线菌或真菌引起的一种慢性化脓性肉芽肿性疾病，是由

13、多种放线菌或真菌引起的一种慢性化脓性肉芽肿性疾病，主要感染足部，以肿胀、窦道和颗粒为特征。主要感染足部，以肿胀、窦道和颗粒为特征。n ncausedbyfungiarecalledeumycetoma(40%)n nActinomycetomaiscausedbyactinomycetes(60%)n nItischaracterizedbytheformationofabscess,whichcontainlargeaggregatesoffungaloractinomycetefilamentsknownasgrains3434n nEumycetomaEumycetoma Dark gr

14、ainsDark grains Madurella Madurella mycetomatismycetomatis Leptosphaeria Leptosphaeria senegalensissenegalensis Exophiala jeanselmeiExophiala jeanselmei Pale grainsPale grains Fusarium Fusarium sp.sp.AcremoniumAcremonium sp.sp.Scedosporium Scedosporium apiospermum apiospermum n nActinomycetomaActino

15、mycetomaWhite-yellow grainsWhite-yellow grains Actinomadura Actinomadura maduraemadurae Nocardia brasiliensisNocardia brasiliensisYellow-brown grainsYellow-brown grains Streptomyces Streptomyces somaliensissomaliensisRed-pink grainsRed-pink grains Actinomycetoma Actinomycetoma pellettieripellettieri

16、3535深部真菌感染深部真菌感染n n引起深部感染的真菌包括两大类：致病性真菌与条件致病性真菌n n致病性真菌主要有组织胞浆菌、球孢子菌、副球孢子菌和芽生菌，这些真菌均属二相性。多见于美洲，我国极少见。它们侵袭深部组织和内脏以及全身，引起慢性肉芽肿样炎症、溃疡和坏死。n n条件致病性真菌包括有：念珠菌、隐球菌、曲霉菌与毛霉菌、肺孢子菌等。3636Characteristics of systemic dimorphic mycosesn nAre uncommon,Are uncommon,often occurs in often occurs in endemic areasendemic

17、 areas n nMost infections are Most infections are asymptomaticasymptomatic or self-limiting or self-limitingn nin immune-compromised hosts,infections are in immune-compromised hosts,infections are often fataloften fataln nThe pattern of infection are similarThe pattern of infection are similar Route

18、 of acquisition is inhalation Route of acquisition is inhalation Pulmonary infectionPulmonary infection Disseminated infection(Disseminated infection(Blood,Bone marrow,Brain and Blood,Bone marrow,Brain and CSF,Joint)CSF,Joint)3737Coccidioidomycosisn nCoccidiodes immitis Coccidiodes immitis is is con

19、sidered to be the considered to be the most most virulentvirulent of fungal pathogens.of fungal pathogens.n nRestricted to hot,semi-arid Restricted to hot,semi-arid areas of SW USA and areas of SW USA and Mexico.Mexico.n nGrows in the soil,but Grows in the soil,but inhalation of a single spore inhal

20、ation of a single spore can initiate infection.can initiate infection.In infected tissues,C.immitis appears as a mixture of endospores and spherules.ConidiaSpherules3838Coccidioidomycosis:A.A.Encounter:Encounter:Mycelium found in dry,dusty soil.Contact by Mycelium found in dry,dusty soil.Contact by

21、inhalationinhalation of of arthroconidiaarthroconidiaB.B.Spread:Spread:Most commonly an asymptomatic self limited pulmonary Most commonly an asymptomatic self limited pulmonary disease,but may spread via the blood to skin,soft tissues,bones,disease,but may spread via the blood to skin,soft tissues,b

22、ones,joints and joints and meningesmeninges.C.C.Immune Response:Immune Response:T-cell mediated(Th-1)T-cell mediated(Th-1)D.D.Evasion of Defenses:Evasion of Defenses:Resistant to killing by phagocytesResistant to killing by phagocytes-protein rich,hydrophobic outer wallprotein rich,hydrophobic outer

23、 wall-alkaline halo associated with-alkaline halo associated with ureaseurease E.E.Damage:Damage:secreted secreted proteinasesproteinases break down collagen,break down collagen,elastinelastin hemoglobin,hemoglobin,IgGIgG&IgAIgA39391.Ethnicity:Filipinos,African Americans,Native Americans at higher r

24、isk2.Age:Extremes more susceptible3.Sex:Males more susceptible4.Pregnancy:3rd trimester5.ImmunosuppressionF.Diagnosis1.Exam:Suppurative or granulomatous inflammation2.Histopathology:spherules or endospores seen in sputum,exudates or tissue3.Culture:danger,highly infectious!4.Serology:Complement fixa

25、tion assay(in cerebrospinal fluid),particle agglutination assay G.Treatment1.Amphotericin B followed by an azoleE.Risk FactorsCoccidioidomycosis:4040Histoplasmosis (also called(also called cave diseasecave disease)Caused by the dimorphic fungus Histoplasma capsulatumTuberculated macroconidia,grown a

26、t 25CIntracellular yeast at 37CHistoplasmosis is characterized by intracellular growth of the pathogen in macrophages and a granulomatous reaction in tissue.These granulomatous foci may reactivate and cause dissemination of fungi to other tissues.4141HistoplasmosisA.A.EncounterEncounter.H.capsulatum

27、H.capsulatum grows in soil,especially soil grows in soil,especially soil contaminated by guano.contaminated by guano.Inhalation of conidia from Inhalation of conidia from the environment is source the environment is source of infection.This is more of infection.This is more likely in endemic areas.I

28、n likely in endemic areas.In U.S.these include the U.S.these include the Atlantic Ocean to N.Dakota Atlantic Ocean to N.Dakota(500,000 cases/year in(500,000 cases/year in U.S.),except New England U.S.),except New England&Florida.Most cases occur&Florida.Most cases occur in Ohio Valley and in Ohio Va

29、lley and Mississippi Valley)Mississippi Valley)4242 More HistoplasmosisMore Histoplasmosis1.1.90%of cases are asymptomatic,but in rare cases flu like respiratory 90%of cases are asymptomatic,but in rare cases flu like respiratory symptoms occursymptoms occur2.2.Disseminated Disseminated histoplasmos

30、ishistoplasmosis occurs in 1:200 cases and is diagnosed occurs in 1:200 cases and is diagnosed frequently in patients with AIDS living in the central U.S.frequently in patients with AIDS living in the central U.S.3.3.In these cases,the organism spreads In these cases,the organism spreads via bloodvi

31、a blood from the lung to from the lung to involve bone marrow,adrenal glands,heart valves and CNSinvolve bone marrow,adrenal glands,heart valves and CNS4.4.Spread can also be associated with underlying lung disease(e.g.,Spread can also be associated with underlying lung disease(e.g.,emphysema).emphy

32、sema).B.SpreadC.Immune Response1.Cell-mediated responses are of primary importance2.Activated macrophage can kill yeast cellsD.Evasion of Defenses1.Survival in macrophages elevates pH of phagosomes2.Yeast cells absorb iron(siderophore)and calcium from host3.Alteration of cell surface 4343Histoplasmo

33、sis 1.Direct histology and culture of blood or bone marrow2.Serological testing for antibody and histoplama antigen in blood and urine.E.DiagnosisD.Damage1.Lung-bronchial obstruction and inflammatory sequelae2.Disseminated histoplasmosis-fulminant disease that may result in toxic shock3.CNS-fatal if

34、 untreated.4444Even More HistoplasmosisF.TreatmentAmphotericin still mainstay of therapy vs.disseminated and severe pulmonary histoplasmosis.Ketoconasole or itraconasole is effective as therapy for self-limited disease(used in AIDS).Ocular HistoplasmosisA small fraction of individuals form scar tiss

35、ue in the retina many years after the original histoplasmosis infection.Live organisms cannot be recovered from these specimens.The scarring can obscure the macula and lead to loss of central vision.The first signs are small“histo spots”.Advanced disease is treated with laser photocoagulation to lim

36、it the proliferation of blood vessels.4545Blastomycosis Granulomatous mycotic infection Granulomatous mycotic infection that predominantly involves lungs that predominantly involves lungs and skin;but can spread to other and skin;but can spread to other organs.Most prevalent in males organs.Most pre

37、valent in males 40-60 years of age and children.40-60 years of age and children.Blastomyces dermatitidis Dimorphic organism originates in the soil and infection ensues by inhalation of spores.Converts to yeast in animal hosts or at 37o in vitro.4646Blastomycosisn nEncounterEncounter:Most cases are i

38、n southern,central,and southeastern USA.:Most cases are in southern,central,and southeastern USA.Infection is by inhalation of spores.Infection is by inhalation of spores.n nSpread:Spread:The pulmonary infection is either self-limited or progressive.The pulmonary infection is either self-limited or

39、progressive.Dissemination often occurs to the skin and to the bone-80%of Dissemination often occurs to the skin and to the bone-80%of patients have large skin lesions;a large number also have patients have large skin lesions;a large number also have granulomatous pulmonary lesions.granulomatous pulm

40、onary lesions.n nRisk Factors:Risk Factors:Occupational contact with soil;owning a dog.Living in Occupational contact with soil;owning a dog.Living in endemic area.endemic area.n nEvasion of Defenses:Evasion of Defenses:Escapes phagocytosis by neutrophils and Escapes phagocytosis by neutrophils and

41、monocytes by shedding its surface antigen after infectionmonocytes by shedding its surface antigen after infectionn nDamage:Damage:Consequence of the immune response to the organismskin Consequence of the immune response to the organismskin lesions,respiratory infiltrates.lesions,respiratory infiltr

42、ates.n nDiagnosis:Diagnosis:based on clinical findings and microscopic detection of based on clinical findings and microscopic detection of organisms in tissue specimensorganisms in tissue specimens47471.1.AmphotericinAmphotericin B is the drug of choice for rapidly progressive B is the drug of choi

43、ce for rapidly progressive blastomycosisblastomycosis2.2.ItraconazoleItraconazole or or KetoconazoleKetoconazole for less severe cases for less severe casesImmune response1.Alveolar macrophage provide a first line of defense.2.T-cell stimulated PMNs kill Blastomyces cells by oxidative mechanisms.3.C

44、onidia are more sensitive to killing by PMNs because yeast are too big.4.TH-1 response is of primary importanceBlastomycosisTreatment4848Opportunistic fungal infectionsn nOpportunistic mycoses are fungal infections that do not normally Opportunistic mycoses are fungal infections that do not normally

45、 cause disease in healthy people,but do cause disease in people cause disease in healthy people,but do cause disease in people with weakened immune defenses(immunocompromised people).with weakened immune defenses(immunocompromised people).Weakened immune function may occur due to inherited Weakened

46、immune function may occur due to inherited immunodeficiency diseases,drugs that suppress the immune immunodeficiency diseases,drugs that suppress the immune system(cancer chemotherapy,corticosteroids,drugs to prevent system(cancer chemotherapy,corticosteroids,drugs to prevent organ transplant reject

47、ion),radiation therapy,infections(e.g.,HIV),organ transplant rejection),radiation therapy,infections(e.g.,HIV),cancer,diabetes,advanced age and malnutrition.cancer,diabetes,advanced age and malnutrition.n nThe most common infections are:The most common infections are:n nCandidiasisCandidiasisn nCryp

48、tococcosisCryptococcosisn nAspergillosisAspergillosisn nPneumocystiscariniipneumonia(PCP)Pneumocystiscariniipneumonia(PCP)n nPenicillosismarneffeiPenicillosismarneffei4949白假丝酵母菌白假丝酵母菌(Candida albicans)形态：圆形或卵圆形单细胞真菌，革兰阳性繁殖：出芽繁殖，形成假菌丝，在组织易形成芽生孢子培养：普通琼脂、血琼脂与沙保培养基 需氧。室温或 37甚至42生长良好 菌落灰白色或奶油色，表面光滑，带有浓厚的

49、酵母气味。有大量向下生长的营养假菌丝，呈类酵母型。在玉米粉培养基上可长出厚膜孢子n n属于假丝酵母菌属，俗称白念，为酵母型真菌，是条件致病菌属于假丝酵母菌属，俗称白念，为酵母型真菌，是条件致病菌 可引起皮肤、黏膜和内脏的急性或慢性炎症，即念珠菌病，是最可引起皮肤、黏膜和内脏的急性或慢性炎症，即念珠菌病，是最常见的深部感染真菌病，口腔念珠菌病是艾滋病患者最先出现的常见的深部感染真菌病，口腔念珠菌病是艾滋病患者最先出现的继发性感染。继发性感染。n n生物学特性生物学特性5050假菌丝和厚膜孢子5151Systemic involvementn nUrinary tract infectionn n

50、Pulmonary candidiasis n nEndocarditis n nMeningitisn nCandidaemia(septicaemia)Infancy,old age,pregnancy,prolong antibiotic,HIV/AIDS,diabetes 5252微生物检查：微生物检查：1 1、直接镜检：同时见出芽的念珠菌与假菌丝、直接镜检：同时见出芽的念珠菌与假菌丝、直接镜检：同时见出芽的念珠菌与假菌丝、直接镜检：同时见出芽的念珠菌与假菌丝 2 2、分离培养与鉴定：假菌丝，芽生孢子、分离培养与鉴定：假菌丝，芽生孢子、分离培养与鉴定：假菌丝，芽生孢子、分离培养与鉴定：