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Cryptococcus (Latin for "hidden sphere") is a genus of fungus. These fungi grow in culture as yeasts. The sexual forms or teleomorphs of Cryptococcus species are filamentous fungi in the genus Filobasidiella. The name Cryptococcus is used when referring to the yeast states of the fungi.

General characteristics

The cells of these species are covered in a thin layer of glycoprotein capsular material that has a gelatin-like consistency and that, among other functions, serves to help extract nutrients from the soil. However, the C. neoformans capsule is different, in being richer in glucuronic acid and mannose, having O-acetyl groups,^[1] and functioning as the major virulence factor in cryptococcal infection and disease.^[2]

Infectious species

There are about 37 recognized species of Cryptococcus, but the taxonomy of the group is currently being re-evaluated with up-to-date methods. The majority of species live in the soil and are not harmful to humans. Very common species include Cryptococcus laurentii and Cryptococcus albidus. Of all species, Cryptococcus neoformans is the major human and animal pathogen. However, Cryptococcus laurentii and Cryptococcus albidus have been known to occasionally cause moderate-to-severe disease, to be specific meningitis, in human patients with compromised immunity (owing to HIV infection, cancer chemotherapy, metabolic immunosuppression, et cetera).^[3]^[4]

C. neoformans

Cryptococcus neoformans is the most prominent medically important species. It is best known for causing a severe form of meningitis and meningo-encephalitis in people with HIV/AIDS. It may also infect organ transplant recipients and people receiving certain cancer treatments.^[5] C. neoformans is found in the droppings of wild birds, often pigeons; when dust of the droppings is stirred up it can infect humans or pets that inhale the dust.^[5] Infected humans and animals do not transmit their infection to others; they are not infectious.^[5] When plated on Niger or birdseed agar, C. neoformans produces melanin, which causes the colonies to have a brown color, and it is believed that this melanin production may be an important virulence factor.^[6]

Field stain showing Cryptococcus species in lung tissue

C. gattii

Cryptococcus gattii (formerly Cryptococcus neoformans var gattii) is endemic to tropical parts of the continent of Africa and Australia. It is capable of causing disease (cryptococcosis) in non-immunocompromised people. It has been isolated from eucalyptus trees in Australia. Since 1999, there has been an outbreak of Cryptococcus gattii infections in eastern Vancouver Island,^[7] an area not generally thought to be endemic for this organism. Cases have since been described in the Pacific Northwest, in both Canada and the United States.^[8]

C. albidus

Cryptococcus albidus is a species that has been isolated from the air, dry moss in Portugal, grasshoppers in Portugal, and tubercular lungs.^[9] The colonies on a macroscopic level are cream-color to pale pink, with the majority of colonies being smooth with a mucoid appearance. Some of the colonies have been found to be rough and wrinkled, but this is a rare occurrence.^[10] This species is very similar to Cryptococcus neoformans, but can be differentiated because it is phenol oxidase-negative, and, when grown on Niger or birdseed agar, C. neoformans produces melanin, causing the cells to take on a brown color while the C. albidus cells stay cream-color.^[6]^[11] On a microscopic level C. albidus has an ovoid shape, and when viewed with India ink it is apparent that a capsule is present. This species also reproduces through budding. The formation of pseudohyphae has not been seen. C. albidus is able to use glucose, citric acid, maltose, sucrose, trehalose, salicin, cellobiose, and inositol, as well as many other compounds, as sole carbon sources. This species is also able to use potassium nitrate as a nitrogen source. C. albidus produces urease, as is common for Cryptococcus species.^[12] Cryptococcus albidus is very easily mistaken for other Cryptococcus species, as well as species from other genus of yeast, and as such should be allowed to grow for a minimum of seven days before attempting to identify this species.

While this species is most frequently found in water and plants and is also found on animal and human skin, it is not a frequent human pathogen. Cases of C. albidus infection have increased in humans during the past few years, and it has caused ocular and systemic disease in those with immunoincompetent systems, for example, patients with AIDS, leukemia, or lymphoma.^[10]^[11] While systemic infections have been found with increasing regularity in humans, it is still relatively rare in animals. To date there have only been two cases of infection in horses, a case of systemic infection in a house cat, and in 2005 the first confirmed case of C. albidus systemic infection in a dog was confirmed. It is believed that C. albidus entered unencapsulated into a Doberman Pinscher named Daisy through her lungs, and infected the lung tissue. It is also believed that once the infection was embedded in Daisy’s lung tissue, the yeast became encapsulated, the presence of this important virulence factor thereby allowing C. albidus to spread through her system. While immunodeficiency seems to be required for a systemic infection of C. albidus to occur in humans, this does not appear to be the case in animals, though further studies will have to be done to confirm whether or not this is the case in animals. One thing that is confirmed is that a systemic infection in animals is typically seen when antibiotics are administered for extended periods of time. The only accepted treatment in humans and animals is the long-term administration of amphotericin B. The administration of amphotericin B in animals has been successful, but in humans the treatment usually has poor results.^[6]

Cryptococcus albidus var. albidus is a variety of C. albidus that has been considered unique. It differs from Cryptococcus neoformans because of its ability to assimilate lactose, but not galactose. This species is also considered unique because its strains have a maximum temperature range from between 25 °C and 37 °C. This is important because it violates van Uden’s rule, which states that the yeast strains of a particular species cannot have their maximum growth temperature vary by more than 5 °C.^[13] However, there is some debate as to whether or not this maximum temperature range for the strains of C. albidus is accurate, because other research has shown that C. albidus var. albidus strains cannot grow at 37 °C.^[11] Another variety, Cryptococcus albidus var. diffluens is different from Cryptococcus neoformans in that it can assimilate melibiose but not galactose.^[6]

C. uniguttulatus

Cryptococcus uniguttulatus (Filobasidium uniguttulatus is a teleomorph) was the first non-neoformans Cryptococcus to infect a human. It was isolated from ventricular fluid from a patient having had a neurosurgical procedure. This species was found to be very sensitive to amphotericin B at the minimum inhibitory dose. This species was first isolated from a human nail.

Non-infectious species

Cryptococcus adeliensis
Cryptococcus aerius
Cryptococcus albidosimilis
Cryptococcus antarcticus
Cryptococcus aquaticus
Cryptococcus ater
Cryptococcus bhutanensis
Cryptococcus consortionis
Cryptococcus curvatus
Cryptococcus phenolicus
Cryptococcus skinneri
Cryptococcus terreus
Cryptococcus vishniacci

References

^ Ross A, Taylor IE (1981) Extracellular glycoprotein from virulent and avirulent Cryptococcus species. Infection and Immunity. 31(3):911–8
^ Casadevall A and Perfect JR (1998) Cryptococcus neoformans. American Society for Microbiolgy, ASM Press, Washington DC, 1st edition.
^ Cheng MF, Chiou CC, Liu YC, Wang HZ, Hsieh KS (2001) Cryptococcus laurentii fungemia in a premature neonate. Journal of Clinical Microbiology. 39(4):1608–11. A good review of C. laurentii cases till year 2000.
^ Results from a PubMed Search on terms: "Cryptococcus albidus Infection" – list of references for C. albidus clinical infections.
^ ^a ^b ^c "What is Cryptococcus infection (cryptococcosis)?". Center for Disease Control and Prevention. April 28, 2010. Retrieved 8 March 2012.
^ ^a ^b ^c ^d Labrecque O., Sylvestre D. and Messier S. (2005) Systemic Cryptococcus albidus infection in a Doberman Pinscher. J Vet Diagn Invest 17:598-600
^ Lindberg J, Hagen F, Laursen A, et al. (2007). "Cryptococcus gattii Risk for Tourists Visiting Vancouver Island, Canada". Emerg Infect Dis 13 (1): 178–79. doi:10.3201/eid1301.060945. PMC 2725802. PMID 17370544.
^ MacDougall L, Kidd SE, Galanis E, et al. (2007). "Spread of Cryptococcus gattii in British Columbia, Canada, and Detection in the Pacific Northwest, USA". Emerg Infect Dis 13 (1): 42–50. doi:10.3201/eid1301.060827. PMC 2725832. PMID 17370514.
^ Fonseca A., Scorzeti G., and Fell J. (2000) Diversity in the yeast Cryptococcus albidus and related species as revealed by ribosomal DNA sequence analysis. Can. J. Microbiol. 46:7-27
^ ^a ^b http://www.doctorfungus.org/thefungi/Cryptococcus_albidus.php Results from a search on Doctor Fungus
^ ^a ^b ^c (2006) 0609-1 Cryptococcus albidus. Cmpt Mycol Plus
^ Cryptococcus albidus. Mycology Online. The University of Adelaide. http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Yeasts/Cryptococcus/C_albidus.html
^ Vishniac H. S., Kurtzman C. P. (1992) Cryptococcus anarcticus sp. nov. and Cryptococcus albidosimilis sp. nov., Basidioblasomycetes from Antarctic Soils. Int. J. Syst. Bacteriol. 42(4) 547-553

External links

Wikispecies has information related to: Cryptococcus (Filobasidiaceae)

UpToDate Contents

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1. 中枢神経系以外のクリプトコッカス感染症 cryptococcal infection outside the central nervous system
2. クリプトコッカス感染症の微生物学および疫学 microbiology and epidemiology of cryptococcal infection
3. AIDS関連クリプトコッカス髄膜脳炎 aids associated cryptococcal meningoencephalitis
4. HIV血清陰性患者におけるクリプトコッカス髄膜脳炎の臨床症状および診断 clinical manifestations and diagnosis of cryptococcal meningoencephalitis in hiv seronegative patients
5. HIV血清陰性患者におけるクリプトコッカス髄膜脳炎および播種性感染症の治療 treatment of cryptococcal meningoencephalitis and disseminated infection in hiv seronegative patients

English Journal

PCR-REA as an important tool for the identification of Cryptococcus neoformans and Cryptococcus gattii from human and veterinary sources.

Cordeiro RA, Costa AK, Brilhante RS, de Lima RA, Castelo-Branco Dde S, Ribeiro JF, Monteiro AJ, Rocha FA, Sidrim JJ, Rocha MF.SourceDepartment of Pathology and Legal Medicine, School of Medicine, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, CE, Brazil; Department of Pathology and Legal Medicine, School of Medicine, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, CE, Brazil.
Veterinary microbiology.Vet Microbiol.2011 Dec 29;154(1-2):180-4. Epub 2011 Jul 7.
The extraordinary ability of Cryptococcus species to cause disease has focused the attention of scientists on finding ways to improve their identification methods. In this study, PCR-REA, manual methods (morphological and biochemical characteristics), API 20C and VITEK 2 were used to test identify a
PMID 21802868

Fungal diversity in cow, goat and ewe milk.

Delavenne E, Mounier J, Asmani K, Jany JL, Barbier G, Le Blay G.SourceUniversité Européenne de Bretagne, France.
International journal of food microbiology.Int J Food Microbiol.2011 Dec 2;151(2):247-51. Epub 2011 Sep 8.
Knowledge of fungal diversity in the environment is poor compared with bacterial biodiversity. In this study, we applied the denaturing high-performance liquid chromatography (D-HPLC) technique, combined with the amplification of the ITS1 region from fungal rDNA, for the rapid identification of majo
PMID 21944758

Japanese Journal

Characterization of D-galacturonate reductase purified from the psychrophilic yeast species Cryptococcus diffluens(ENZYMOLOGY, PROTEIN ENGINEERING, AND ENZYME TECHNOLOGY)

Hamada Shohei,Seike Yuichiro,Tanimori Shinji,Sakamoto Tatsuji,Kishida Masao
Journal of bioscience and bioengineering 111(5), 518-521, 2011-05
… D-Galacturonic acid reductase was purified from a psychrophilic yeast strain of Cryptococcus diffluens, which was isolated from Satho, a traditional alcohol drink in Thailand. …
NAID 110008661196

Possible participation of the Rho/Rho-associated coiled-coil-forming kinase pathway in the cell death of Cryptococcus neoformans caused by Staphylococcus aureus adherence

Ikeda Reiko
Microbiology and immunology 55(8), 552-557, 2011-08
NAID 40018961416

Related Pictures

★リンクテーブル★

リンク元	「髄膜炎」「不完全菌」「クリプトコッカス属」「cryptococcal」「cryptococci」
拡張検索	「Cryptococcus neoformans」「Cryptococcus neoformans infection」「Cryptococcus属」

「髄膜炎」

Cryptococcus
	Cryptococcus neoformans
Scientific classification
Kingdom:	Fungi
Phylum:	Basidiomycota
Class:	Tremellomycetes
Order:	Tremellales
Family:	Tremellaceae
Genus:	Cryptococcus; Vuill.
Type species
	Cryptococcus neoformans;
Synonyms
	Filobasidiella

　　[★]

英: meningitis
同: 脳脊髄膜炎、
関: 蛋白細胞解離

病因

感染症(細菌、ウイルス、真菌など)、悪性腫瘍の浸潤　→　髄膜の炎症

分類

病原体

細菌性髄膜炎

菌血症→脳脈絡叢→髄腔
菌体成分(LPSなど)→BBB, 上衣細胞、脳細胞の障害。神経膠細胞による炎症サイトカインの分泌

無菌性髄膜炎

血行性、あるいは神経軸索によりウイルスが髄腔に波及。

細菌性髄膜炎：様々
ウイルス性髄膜炎：コクサッキーウイルス、エコーウイルス、ムンプスウイルス、単純ヘルペスウイルス、風疹ウイルス、麻疹ウイルス、水痘・帯状疱疹ウイルス
真菌性髄膜炎：クリプトコッカス髄膜炎
結核性髄膜炎：結核菌
梅毒性髄膜炎：梅毒菌

臨床経過

宿主要因と髄膜炎に関わる病原体

頻度・年齢階層が資料によって異なるため混乱しないように注意。

YN.J-137改変

4ヶ月未満	B群溶連菌(50%)	大腸菌(25%)	インフルエンザ菌(20%)	リステリア菌(1%)
4ヶ月～6歳未満	インフルエンザ菌(70%)	肺炎球菌(25%)
6歳～50歳未満	肺炎球菌(65%)	インフルエンザ菌(10%)	髄膜炎菌
50歳以上	肺炎球菌(80%)	黄色ブドウ球菌
免疫不全者	クレブシエラ	連鎖球菌	緑膿菌	黄色ブドウ球菌	真菌

first aid step1 2006 p.161

Newborn (0–6 mos)	Children (6 mos–6 yrs)	6–60 yrs	60 yrs +
Streptococcus agalactiae	Streptococcus pneumoniae	Neisseria meningitidis	Streptococcus pneumoniae
Escherichia coli	Neisseria meningitidis	Enteroviruses	Gram-negative rods
Listeria	Haemophilus influenzae type B	Streptococcus pneumoniae	Listeria
	Enteroviruses	HSV

HIV: Cryptococcus, CMV, toxoplasmosis (brain abscess), JC virus (PML)

incidence of H. influenzae meningitis has ↓ greatly with introduction of H. influenzae vaccine in last 10–15 years.

CBT QB vol2 p.562

	1位	2位	3位
新生児	大腸菌	B群溶連菌	リステリア菌
小児期(6歳以下)	インフルエンザ菌	肺炎球菌
成人	肺炎球菌	髄膜炎菌

IMD.1042

年齢	病原体
3ヶ月未満	B群溶連菌	大腸菌	リステリア菌
3ヶ月以上の乳小児	インフルエンザ菌	肺炎球菌
成人	肺炎球菌	髄膜炎菌
高齢者	肺炎球菌	グラム陰性桿菌	リステリア菌

小児細菌性髄膜炎起炎菌(PED.606)

		<3か月	3か月≦
グラム陽性	球菌	Streptococcus agalactiae Streptococcus pneumoniae Staphylococcus Enterococcus faecalis	Streptococcus pneumoniae(PSSP/PISP/PRSP)
グラム陽性	桿菌	Listeria monocytogenes	Listeria monocytogenes
グラム陰性	球菌	Neisseria meningitidis	Neisseria meningitidis
グラム陰性	桿菌	Escherichia coli Enterobacter cloacae Serratia marcescens	Haemophilus influenzae type b

新生児

Streptococcus agalactiaeは産道感染
Escherichia coliもおそらく産道感染

新生児と老人

Listeria monocytogenesは産道感染するので新生児に多い。新生児と老人に多いのは通性細胞内寄生菌で細胞性免疫の弱い宿主に感染やすいため？

乳児～幼児

Haemophilus influenzae type B

乳児～大人

Enteroviruses
Neisseria meningitidis

小児～大人

Herpes simplex virus

乳児～老人

Streptococcus pneumoniae

老人

グラム陰性桿菌は老人

髄膜炎の鑑別

	細菌性髄膜炎	ウイルス性髄膜炎	結核性髄膜炎	真菌性髄膜炎	癌性髄膜炎
外観	混濁	clear	水様～キサントクロミー日光微塵	clear～日光微塵	clear～キサントクロミー
圧 70-180 (mmH2O)	↑↑ 200～800以上	↑ 200～300	↑ 200～800	↑ 200～800	↑ 200～300
細胞 0-5 (/mm3)	500～数百万	10～1,000	25～1,000	25～1,000	25～500
細胞 0-5 (/mm3)	好中球	リンパ球	リンパ球	リンパ球	好中球
タンパク 15-45 mg/dl	↑↑ 50～1,500	↑ 正常～100	↑ 50～500	↑ 100～500	↑ 50～500
糖 50-80 mg/dl	↓↓ 0～40	→ 正常	↓↓ ～40	↓↓ ～40	↓ ～40

予後不良因子

入院時の状態に依存する：痙攣、意識レベルの変化、低血圧 (IRE.407)

国試

100F048

「不完全菌」

　　[★]

英: imperfect fungus, imperfect fungi
関: 完全菌、真菌

不完全菌の特徴

子のう菌・担子菌には、単細胞で生活する酵母の形を取るものと、菌糸体を発達させるものがある。不完全菌にも、それに対応して、不完全酵母類・不完全糸状菌類がある。不完全酵母は出芽や分裂によって増殖する。

不完全酵母

Candida
Cryptococcus

参考

http://ja.wikipedia.org/wiki/%E4%B8%8D%E5%AE%8C%E5%85%A8%E8%8F%8C

「クリプトコッカス属」

　　[★]

英: Cryptococcus
同: Cryptococcus属
関: 真菌

クリプトコッカス科
出芽で増殖
不完全真菌
莢膜を
仮性菌糸を形成しない
キャンディン系抗真菌薬は無効
アゾール系抗真菌薬(イトラコナゾール、フルコナゾール)が第一選択の治療薬。アムホテリシンBは有効だが副作用が大きい。

「cryptococcal」

　　[★]

クリプトコッカスの

関: cryptococci、Cryptococcus

「cryptococci」

　　[★]

クリプトコッカス

関: cryptococcal、Cryptococcus

「Cryptococcus neoformans」

　　[★]

ラ: Cryptococcus neoformans, C. neoformans
同: Filobasidiella neoformans、クリプトコッカス・ネオフォルマンス
関: クリプトコッカス症

厚い莢膜
不完全菌酵母
担子菌
感染組織内、培地でも莢膜を持つ単細胞(酵母)として増殖
中枢神経系に強い親和性を有する。

分布

ミルク、加重、健常者の皮膚、消化管
土壌特にハトその他の鳥類、コアラの糞などで汚染された土壌に豊富に存在

分離培養

染色

墨汁染色

感染症

クリプトコッカス症(肺クリプトコッカス症、クリプトコッカス髄膜炎、播種性クリプトコッカス症)

感染経路は空気感染　→　肺クリプトコッカス症

細胞免疫能低下患者　→　髄膜や脳に二次感染

HIV患者では高頻度にクリプトコッカス髄膜炎

参考

真菌の写真 - Fungal Images

http://www.asm.org/Division/c/fungi.htm

「Cryptococcus neoformans infection」

　　[★]

クリプトコッカス・ネオフォルマンス感染症、クリプトコッカス・ネオフォルマンス感染

「Cryptococcus属」

　　[★] クリプトコッカス属

[1] Ross A, Taylor IE (1981) Extracellular glycoprotein from virulent and avirulent Cryptococcus species. Infection and Immunity. 31(3):911–8

[2] Casadevall A and Perfect JR (1998) Cryptococcus neoformans. American Society for Microbiolgy, ASM Press, Washington DC, 1st edition.

[3] Cheng MF, Chiou CC, Liu YC, Wang HZ, Hsieh KS (2001) Cryptococcus laurentii fungemia in a premature neonate. Journal of Clinical Microbiology. 39(4):1608–11. A good review of C. laurentii cases till year 2000.

[4] Results from a PubMed Search on terms: "Cryptococcus albidus Infection" – list of references for C. albidus clinical infections.

[CDC-5] "What is Cryptococcus infection (cryptococcosis)?". Center for Disease Control and Prevention. April 28, 2010. Retrieved 8 March 2012.

[Labrecque_O._2005-6] Labrecque O., Sylvestre D. and Messier S. (2005) Systemic Cryptococcus albidus infection in a Doberman Pinscher. J Vet Diagn Invest 17:598-600

[7] Lindberg J, Hagen F, Laursen A, et al. (2007). "Cryptococcus gattii Risk for Tourists Visiting Vancouver Island, Canada". Emerg Infect Dis 13 (1): 178–79. doi:10.3201/eid1301.060945. PMC 2725802. PMID 17370544.

[8] MacDougall L, Kidd SE, Galanis E, et al. (2007). "Spread of Cryptococcus gattii in British Columbia, Canada, and Detection in the Pacific Northwest, USA". Emerg Infect Dis 13 (1): 42–50. doi:10.3201/eid1301.060827. PMC 2725832. PMID 17370514.

[9] Fonseca A., Scorzeti G., and Fell J. (2000) Diversity in the yeast Cryptococcus albidus and related species as revealed by ribosomal DNA sequence analysis. Can. J. Microbiol. 46:7-27

[doctorfungus.org-10] ttp://www.doctorfungus.org/thefungi/Cryptococcus_albidus.php Results from a search on Doctor Fungus

[ReferenceA-11] (2006) 0609-1 Cryptococcus albidus. Cmpt Mycol Plus

[12] Cryptococcus albidus. Mycology Online. The University of Adelaide. http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Yeasts/Cryptococcus/C_albidus.html

[13] Vishniac H. S., Kurtzman C. P. (1992) Cryptococcus anarcticus sp. nov. and Cryptococcus albidosimilis sp. nov., Basidioblasomycetes from Antarctic Soils. Int. J. Syst. Bacteriol. 42(4) 547-553

Cryptococcus

Cryptococcus neoformans
Scientific classification
Kingdom:	Fungi
Phylum:	Basidiomycota
Class:	Tremellomycetes
Order:	Tremellales
Family:	Tremellaceae
Genus:	Cryptococcus Vuill.
Type species
Cryptococcus neoformans
Synonyms
Filobasidiella

匿名

検索

案内

Cryptococcus