cryptococcus neoformans 1992

5
8/19/2019 Cryptococcus neoformans 1992 http://slidepdf.com/reader/full/cryptococcus-neoformans-1992 1/5  linical Microbiology Newsletter Vol. 14, No. 23 December 1, 1992 ryptococcusneoformans Mark La Rocco Ph.D. Department of Pathology and Laboratory Medicine University of Texas Medical School Houston TX 77225 There is, perhaps, no other fungal pathogen in recent times that has had as dramatic an impact on clinical medicine and public health as Cryptococcus neoformans. Long regarded as an oppor- tunistic pathogen in patients with Hodg- kin's disease, leukemia, diabetes, and prolonged steroid therapy, the morbid- ity and mortality of C. neoformans disease has exploded with the advent of acquired immunodeficiency syndrome (AIDS). Cryptococcal meningitis is the most comm on fife-threatening oppor- tunistic fungal disease in patients infected with the human immuno- deficiency virus (HIV) type 1. In the United States, the prevalence of the disease in this patient population is between 7 and 12% (1-3) and is as high as 20% in AIDS patients in tropical Africa (4). The purpose of this article is to re- view the critical features of the mycol- ogy, ecology, and epidemiology of C. neoformans and to summarize current information on the pathophysiology, diagnosis, and treatment of cryptocoe- cal disease. Mycologic Features C. neoformans is an encapsulated, monomorphic yeast. Two varieties and four serotypes have been described: C. neoformans var. neoformans, which cor- responds to serotypes A and D; and C. neoformans var. gattii, which corre- sponds to serotypes B and C. The de- scription of the teleomorphic form of the organism by Kwon-Chung et al. (5) led to its classification as the basidiomy- cete Fiiobasidiella neoformans F. neo- formans var. neoformans and F. neoformans var. bacillispora), although these forms are rarely encountered un- der laboratory conditions. Species of Cryptococcus produce ovoid to globose vegetative cells with multipolar blasto- conidia attached by a narrow neck. The cells are usually surrounded by a poly- saccharide capsule and may rarely form rudimentary pseudohyphae. All species of Cryptococcus are non-fermentative but will assimilate a variety of carbohy- &ate substrates. Production of urease, inositol assimilation, and microscopic morphology are key features that distin- guish Cryptococcus from other yeasts. At least seven species have been de- scribed but it is generally believed that C. neoforma~ is the only human patho- gen. Separation of species is readily achieved by assimilation studies and pigment production. The latter relates to the ability of C. neoformans to form melanin pigments from o- and p-diphe- nol compounds through the production of phenol oxidase enzymes. The sub- strate for pigment production was origi- nally a medium containing an exWact from pulverized seeds of Guizotia abyssinica bird seed). More recently, bird seed agar has been replaced by caffeic acid medium, which contains the diphenol compounds necessary for pigmentation (6). The four serotypes of C. neoformans are recognized on the ba- sis of the antigenic specificity of the capsular polysaccharide. Although most clinical microbiology laboratories do not serotype isolates, differentiation of the two species variants may be occa- sionally useful for epidemiologic pur- poses. A simple agar medium containing L-canavanine, glycine, and bromthymol blue has been shown to re- liably distinguish the A and D sero- types C. neoformans var. neoformans) from the B and C serotypes (C. neofor- mans vat. gattii) by the ability of only the latter to cause blueing of the media around colonies (7). The current taxonomic classification of C. neoformans has been supported (so far) by recent molecular ap- proaches. Genetic analyses can circum- In This Issue Cryptococcus neoformans ....... 77 An overview of the ecology, epidemiology, mycology, and diagnostic and therapeutic aspects of this important opportunistic pathogen Actinomyces naeslundii Bacteremia ................... 181 A case report Fatal Infection due to Alcaligenes xylosoxidans subsp, xylosoxidans in a Neutropenk Host .......... 82 case report CMNEEI 14(23)177-184,1992 Eiaevier 01964399/92/ 0.00 + 03.00

Upload: julia

Post on 07-Jul-2018

217 views

Category:

Documents


1 download

TRANSCRIPT

Page 1: Cryptococcus neoformans 1992

8/19/2019 Cryptococcus neoformans 1992

http://slidepdf.com/reader/full/cryptococcus-neoformans-1992 1/5

  linical

Microb io logy

News l e t t e r

Vol. 14, No. 23

De cem ber 1, 1992

ryptococcus neoformans

Mark La Rocco Ph.D.

Department of Pathology and Laboratory

Medicine

University of Texas Medical School

Houston TX 77225

There is , perhaps, no other fungal

pathogen in rece nt times that has had as

dramatic an impact on cl in ical med icine

and public heal th as

C r y p t o c o c c u s

n eo fo rma n s . Long rega rded as an oppor-

tunistic pathogen in patients with Hodg-

kin 's d isease, leukem ia, d iabetes , and

prolonged s teroid therapy, the morbid-

i ty and mortal i ty of

C . n e o f o r m a n s

d isease has exp loded wi th the adven t o f

acqu i red imm unodef ic iencysyndrome

(AIDS). C ryptococca l meningit is is the

mos t comm on f i fe- th rea ten ing oppor-

tunistic fu ngal diseas e in patients

in fec ted wi th the hum an imm uno-

deficienc y virus (HIV) ty pe 1 . In the

United States , the prev alence of the

disease in th is pat ient populat ion is

be tween 7 and 12% (1 -3 ) and i s as h igh

as 20% in A IDS pat ients in t ropical

Africa (4).

The pu rpose of th is art icle is to re-

view the cri t ical features of the mycol-

ogy , eco logy , and ep idem io logy o f C .

n e o f o r m a n s

and to sum marize cu rren t

information on the pathophysiology,

diagnosis , an d treatmen t of cryptocoe-

cal disease.

M y c o l o g i c F e a t u r e s

C . n e o f o r m a n s

is an encapsulated,

monomorph ic yeas t. Tw o var ie t ies and

four serotypes have been described: C.

n eo fo rma n s va r . n eo fo rma n s ,

which co r-

responds to serotypes A a nd D; and C.

n eo fo rma n s va r . g a t ti i ,

which co rre-

sponds to serotypes B a nd C. The de -

scription o f the teleomorphic form of

the o rgan ism by Kw on-Chung e t a l . (5 )

led to i ts classificat ion as the b asidiomy-

ce te Fi io b a s id i e l l a n eo fo rm a n s F . n eo -

f o r m a n s v a r. n e o f o r m a n s a n d F .

n eo fo rma n s va r . b a c i l li sp o ra ) ,

al though

these fo rms are ra re ly encoun tered un-

der laboratory condit ions. Species of

Cryp to co ccu s produc e ovoid to globose

vegetat ive cel ls with mult ipolar b lasto-

con id ia a tt ached by a narrow neck . The

cel ls are usual ly surrounded by a poly-

sacchar ide capsu le and may ra re ly fo rm

rudime ntary pseudohyphae. All species

o f

Cryp to co ccu s a re

non-fermentat ive

but wil l ass imilate a variety of carbohy-

&a te substrates . Prod uction of urease,

inositol assimilation, and microscopic

morp hology are ke y features that d is tin-

guish

Cryp to co ccu s

from othe r yeasts .

At least seven species have been de-

scribed but i t is gen eral ly bel ieved that

C . n e o f o r m a ~

is the only human patho-

gen. Separat ion of species is readily

ach ieve d by assimilation studies and

pigm ent production. The lat ter relates

to the abi l i ty of C.

n e o f o r m a n s t o f o r m

melan in p igmen ts f rom o - and p -d iphe-

nol com pounds through the production

of pheno l ox idase enzymes . The sub-

strate for p igment production was origi-

nal ly a m edium containing an exWact

f rom pu lver ized seeds o f

Gu izo t i a

a b yss in i ca b i rd seed ) .

More recen t ly ,

b i rd seed agar has been rep laced by

caffe ic ac id med ium , wh ich con ta ins

the d ipheno l compounds necessary fo r

pigmentat ion (6). The fo ur serotypes of

C. n eo fo rma n s a re

recogn ized on the ba-

sis of the ant igenic specifici ty of the

capsular polysaccharide. Although

most cl in ical m icrobiology laboratories

do not sero type isolates , d ifferent iat ion

of the two spec ies varian t s may be occa-

sional ly useful for epidem iologic pur-

poses. A s imple agar med ium

containing L-canavan ine, g lycine, and

bromthym ol b lue has been shown to re -

l iably dis t inguish the A and D sero-

t yp es C . n eo fo rm a n s va r . n eo fo rma n s )

from the B an d C serotypes (C.

neofor-

ma n s va t . g a t t i i )

by the abi l i ty of only

the lat ter to cause blueing o f the me dia

around c olonies (7).

The curren t taxonom ic classification

of C . n e o f o r m a n s has been supported

(so fa r ) by recen t molecu lar ap -

proaches. Gene tic analyses can circum-

I n T h i s I s su e

C r y pt oc o c cu s n eo f o rm a n s . . . . . . .

77

An overview o f the eco logy,

epidemiology, mycology, and diagnostic

and therapeu tic aspects of this

important opportunistic pathogen

A c t i n o m y c e s n a e s l u n d ii

Bacteremia . . . . . . . . . . . . . . . . . . . 1 8 1

A case report

F a t a l I n f e c t i o n d u e t o

A l c a l i g e n e s

x y l o s o x i d a n s

subsp ,

x y l o s o x i d a n s

in a N e u t r op e n k H o s t . . . . . . . . . . 82

case report

C M N E E I 1 4 ( 2 3 ) 1 7 7 - 1 8 4 , 1 9 9 2 E i a e v i e r

0 1 9 6 4 3 9 9 / 9 2 / 0 . 0 0 + 0 3 . 0 0

Page 2: Cryptococcus neoformans 1992

8/19/2019 Cryptococcus neoformans 1992

http://slidepdf.com/reader/full/cryptococcus-neoformans-1992 2/5

ven t the confus ion o f ten genera ted by

the plast ici ty of phenotyp ic t raits , par-

t icularly whe n deal ing with the anamo r-

ph ic s tages o f fung i. New ly deve loped

techniques that have been succe ssful ly

applied to the taxonom ic s tudy of

cryptococci include rapid restrict ion

mapping using the polyme rase chain re-

act ion (8), res trict ion frag men t polym or-

ph ism ana lys i s o f mi tochondr ia l DNA

(9), and electrophoret ic karyotyping by

pulsed field gel e lectrophoresis (10).

Such s tudies wil l undoubted ly enha nce

our unders tand ing o f the phy logenet ic

relationship between

Cryptococcus and

othe r fungi. Wh ethe r these sophisti-

cated techniques will imp rove our cur-

rent level of proficiency in the

diagnosis and trealm ent of cryptoc occal

disease remains to be determ ined.

E c o l o g y D i s t r i b u t i o n a n d

E p i d e m i o l o g y

The w or ldwide occurrence o f c ryp to -

coccal d isease s tands as evide nce for

the environmen tal ubiquity of

C. neofor-

marts.

As o r ig ina l ly descr ibed by E m-

mons (11), the organism thrives in the

alkaline, high-nitrogen and high-salt

content of dried pigeon feces . Pigeons

are rarely infected, perhaps beca use of

an unsuitably h igh body tem perature of

42°C. Studies have reported the recov -

ery f rom dr ied o r mois t p igeon feces o f

large numbers of v iable organisms w ith

an abi li ty to remain viable for up to 2 yr

(12). This well-described ecologic

niche is val id only

for C. neoform ans

var. neoform ans

and, unt i l recently , the

natural habitat of C. neoform ans var.

gatt i i

was unknow n. Austral ian invest i-

gators , howeve r, have provided com pel-

l ing eviden ce for a b iotrophic

association between C. neoform ans var.

gatt i i

and the r iver red gum t ree

Euca-

lyptus camaldulensis

(13). Their studies

have dem ons t ra ted the env i ronmen ta l

p resence o f C. neoforma ns vat . gat t i i

only during the flowering periods of E.

camaldulensis in late spring (14). They

postulate that the organism m ay be a

smut-L~ke fungu s tha t ov er-w inters in

the deve lop ing buds o f the euca lyp t

with release o f basidiospores in to the

env i ronmen t when the hos t p lan t f low-

ers (13). The y further speculate that the

basidiospores serv e as infectious propa -

gules . Hum an infect ion ma y be direct

or through a vecto r such as (in Austra-

l ia) the koala, wh ich favors the eucalypt

as a foo d source. In support of their hy-

pothesis is the finding of C. neo formans

vat. gatt i i

in the feces o f the koa la and

an endem ic focus o f d i sease caused by

C. neoform ans var. gatt i i

in the rural

aboriginal populat ion of the A ustral ian

Northern Terri tory , a natural habitat for

E. camaldulensis

(14).

These rec ent and fascinat ing find-

ings on the eco logy o f C. neo formans

are in ag reemen t wi th cu rren t ep idemi-

ological d atao The restricted niche o f C.

neoform ans var. gat t ii to E. camaldulen-

sis

may exp lain the p reva lence o f the

varian t in patient isolates from tropical

and subtropical reg ions (15). Similarly,

serotypes A and D C. neoform ans vat .

neo formans)

predom inate in isolates re-

covered from pat ients with and without

AIDS in the United States (16). Of in-

terest is the rec ent report of

C. neofor-

man s vat . gat t i i in an

AIDS pat ient

living in So uthern Californ ia (17) fol-

lowed by ano ther communica t ion an -

nouncing the isolation of the variant

f rom E. camaldulensis

t rees growing in

San F rancisco (18).

H o s t - P a r a s i t e

I n t e r a c t i o n s

The po lysacchar ide capsule o f C .

neo formans

consis ts mainly of g lucu-

ronoxy lomannan and ga lac toxy lman-

nan. I t is considered a v irulence factor

in that s tudies have demo nstrated the

antiphagocytic and imm unosuppressive

effects of ca psular polysacch aride (19,

20). Phen ol oxidase-m ediated synthesis

of me lanin has also been l inked to viru-

lence in a mur ine mod el o f in fec t ion

(21), al though the mecha nism has not

bee n established.

Hos t -defense mechan isms aga ins t C .

neo formans have been s tud ied by sev -

eral investigators. In supp ort of strong

natural huma n resis tance to

C. neofor-

mans ,

immu ni ty appears ac t ive on sev -

eral levels . Neutrophils , macrophages,

ant ibody, sensi t ized T cel ls , and n atural

ki l ler cel ls have al l been shown to have

anti-cryptoeocca l act iv i ty (22). C ell-me-

diated immu nity is probably the most

important protect ive mecha nism against

sys temic c ryp tococca l d isease and re -

cent s tudies have foc used at tent ion on

the imm unomodula to ry e f fec t o f C. neo-

f o r m a n s

on the T-cel l network. Crypto-

cocca l an t igens have been shown to

induce T-suppressor cel ls in mice,

wh ich then b lun ts de layed- type hyper-

sensitivity (23). Induc tion of T-suppres-

sor cel ls in HIV -infected pat ients with

cryp tococcos is ma y fu r ther aggrava te

an a l ready dow n-regu la ted ce l lu la r re -

sponse, perhaps explaining the high in-

c idence and severe symptom ato logy o f

the dise ase in th ese patients.

C r y p t o c o c c a l I n f e c t i o n :

C u r r e n t S t a t u s

In their monogra ph published in

1956 , L i t tman and Z im merm an re -

corde d 151 fatal cases of cryptococco-

sis in the U nited States during the

period from 1949 to 1956 (24). The y

quite correct ly conclude d that the figure

underes t imated the t rue inc idence o f

disease in this country s ince manda tory

repor ting was no t requ i red . The CD C

reported 788 fatal cases in the period

from 1952 to 1963 (an average of 66

cases per ye ar) (25), and 1 ,040 fatal

cases f rom 1965 to 1975 (average o f

104 cases per year) (26). Beginning in

1965 , the Fungus Im munology Branch

of the CD C offered na t ionwide tes ting

of serum and cerebrospinal f lu id for C.

neo formans

antige ns and /or antibodies.

By correla ting their f mdings with avail-

able cl in ical , my cologic, and histologic

data, they docu me nted 1 ,264 proven

N O T E :

N o r e s p o n s ib i l i ty i s a s s u m e d b y t h e P u b l i s h e r

f or an y

i n j u r y a n d / o r d a m a g e t o p e r s o n s o r

p m p e ~ y a s

a m a t t e r o f p r o d u c t s l i a b il i ty , n e g l i g e n c e o r o t h e r w i s e , o r f r o m a n y u s e o r

o p e r a t io n o f a n y m e t h o d s , p r o d u c t s , i n s t r u c ti o n s o r i d e a s c o n t a i n e d i n t h e m a t e r i a l h er e i n . N o s u g g e s t e d t e s t o r p r o c e d u r e s h o u l d b e c a r r i e d o u t u n l e s s , i n t h e r e a d e r ' s j u d g m e n t , i t s r i s k i s

j u s t i f i e d . Be c a u se o f r a p i d a d v a n c e s i n m e d i c a l

s c i e n c e s w e

r e c o m m e n d t h a t t h e i n d e p e n d e n t v e r if i c a t io n o f d i a g n o s e s a n d d r a g d o s a g e s s h o u l d h e m a d e . D i s c u s s i o n s , v i e w s a n d

r e c o m m e n d a t i o n s a s t o m e d i c a l p r o c e d u r e s , c h o i c e o f d r u g s

an d d rag d os ages are

t h e r e sp o n s i b i l i t y o f t h e a u t h o r s .

Clinical Microbiology Ne wsletter

f l S S N 0 1 9 6 - 4 3 9 9 ) i s

i s s u ed t w i ce

m o n t h l y i n

on e i n d exed vo l u me p er year

b y E l s e v i e r S c ie n c e P u b l i s h i n g C o . , I n c. , 6 5 5 A v e n u e o f t h e A m e r i c a s , N e w

Y o r k , N Y 1 0 0 1 0 . S u b s c r ip t i o n p r ic e p er year . 1 3 5 . 0 0 i n c l u d i n g p os t age an d h a n d l i n g i n t h e U n i t e d S t at e s , C a n a d a , e n d M e x i c o . A d d 5 2 . 0 0 f o r p o s t a g e i n t h e r e s t o f th e w o r l d . S e c o n d - c la s s

pc~tage

p a i d a t N e w Y o r k , N Y a n d a t a d d i t io n a l m a i l i n g o f fi c e s . P o s tm a s t e r . S e n d a r k h e s s c h a n g e s t o Clinical Microbiology Newsletter E l s e v i e r S c i e n c e P u b l i s h i n g C o . , I n c ., 6 5 5 A v e n u e

o f t h e A m e r i c a s , N e w Y o r k , N Y 1 0 0 1 0 .

78

0 1 9 6 - 4 3 9 9 / 9 2 / 0 . 0 0 + 0 3 . 0 0 © 1 9 9 2 E l s e v i e r S c i e n c e P u b l i s h i n g C o . , I n c . C l i n i c a l M i c r o b i o l o g y N e w s l e t t e r 1 4 : 2 3 , 1 9 9 2

Page 3: Cryptococcus neoformans 1992

8/19/2019 Cryptococcus neoformans 1992

http://slidepdf.com/reader/full/cryptococcus-neoformans-1992 3/5

 l.)

c~ 5

r j

u .w

0 4

Z.-

Z 2

Y E R

o o o o o o o o o ° ° O

940 197 1980

1990

Figure 1. Incidence of cryptococcal disease in the United States 1960-1991.

cases of cryptococ cosis dur ing a 1 2-yr

per iod cover ing 1965 to 1977 and est i -

mat ed an i nc idence o f 500 cases per

year by 1978 (27) . A 450% increase

over a 20 -y r per iod wa s cons idered , fo r

good reason, a s tar tl ing med ical revela-

t ion. The expanding ro le of C . n eo fo r

m a n s a s a n

opportunist ic pathogen in

the imm unocomp romised pa ti en t was

appreciated 3 y r before the in i tial re-

po r t s o f an acqu i r ed imm unodef i c iency -

l ike syndrome in homosexual men .

Figure 1 depicts the exp losive r i se in

the es t imat ed i nc idence o f c ryp tocooca l

disease in the Uni ted Slates s ince 1981.

Cal cu la t ions a re based on year -by -year

repor ting of AIDS cases in th is count ry

and an es t imat ed 10% p reva l ence o f

cryptoco ccal meningi t i s in th is pat ient

populat ion, a figure wel l supported by

recen t s tud i es (1 -4 ) . Wi th now over

200 ,000 cases o f AIDS repor t ed t o t he

CDC (28 ), po ten t ia l l y 20 ,000 new cases

o f c ryp tococcos i s have occu r red i n t he

last decade , an approximate increase of

1 ,500% as com pared to the previous

decade . In 1991 , 43 ,389 ne w cases o f

AIDS w ere r eco rded by t he CD C, co r re-

iating to potent ial ly ove r 4 ,300 n ew

cases o f c ryp tococcos i s i n t ha t year

a lone , over t h ree t imes t he nu mber o f

cases docum ented during the ent i re pe-

r iod f rom 1965 to 1977 Cryp tococ cal

meningi ti s i s the mo st comm on l i fe-

threatening fung al infection in the pa-

t ient wi th A IDS , and of ten i s the f i rs t

manifestation of the diseas e (1--4).

The c l in ical presentat ion of crypto-

coccos i s i s dependen t upon t he imman-

ocom peten ce of the infec ted patient .

Infect ion may b e superf icial or deep, lo-

cal ized or d i f fuse, and can select ively

involve speci f ic organs or d isseminate

to mul t ip le organ system s. The por tal of

ent ry for the organism is the lung; h ow-

ever , pulmon ary infect ion i s usual ly as-

ymptomat ic. Cent ral nervous system

involvem ent i s the mo st f requent ly d iag-

nosed fo rm o f c ryp tococcos i s , a lt hough

the predi lect ion of C . n e o f o r m a n s fo r

t he CNS has no t been conclus ive ly ex -

plained. Abn ormal i t ies in the cerebro-

spinal f lu id (CS F) are general ly found.

Opening p ressure i s of ten elevated, g lu-

cose i s dep ressed i n ha l f t he cases , p ro -

tein concen t rat ion i s almo st always

e l eva t ed, ce l l coun t s r ange f rom 40 t o

400 l eukocy t es per m m 3 and have a

lymphocy t i c p redominance.

Several recen t repor ts on the cl in ical

presentat ion of cryp tococc al meningi ti s

in HIV-infec ted pat ients have detai led

important d i f feren ces in the cl in ical

f indings as compa red to pat ients wi th-

ou t HIV (1 -4 ) . H IV pa t ien t s o f t en p re-

sent wi th minimal s igns of meningeal

inf lammat ion and m inimal or no abnor-

mal i ti es o f t he CSF. The l ack o f CS F

abnorm al i t ies m ay exist despi te the

p resence o f l a rge numbers o f yeas t s i n

the f lu id . Addi t ional d iagnost ic features

characteristic of this patient popula tion

are l i s ted in Table 1 and are d iscuss ed

fur ther below.

Pr ior to the ad ven t of ant ifungal ther-

apy , symptom at i c c ryp tococcos i s was

invar iably fata . Th e m ortal i ty of the

disease wa s great ly d iminished wi th the

avai labi l i ty of amph oter icin B. A l-

t hough t he usefu lness o f 5 - f l uo rocy to -

s ine a lone i s l imi t ed by deve lopmen t o f

resis tance dur ing therapy, Bennet t and

co l l eagues show ed t he benef i t o f combi -

nat ion therapy wi th amphoter icin B and

5-f luorocy tosine for the t reatment o f

cryptoc occa l meningi t i s (29) . The regi -

men a l l ows a l ow er dose o f ampho-

tericin B to b e use d, thus alleviating

some o f t he t ox i c it y p rob l ems assoc i -

ated wi th the drug. Co mbina t ion ther-

apy wi th ampho ter i c in B and

5-f luorocytosin e for the t reatment of

cryptoc occa l meningi t i s in HIV -in-

fecte d patients has b een disappointing.

Rel apse i s commo n and , m ore impor -

tant ly , m any pat ients ca nnot to lerate the

bone m ar row suppress ion i nduced by 5 -

f luorocytosine. Toxic i ty i s further am -

pf i f ied in pat ients t reated w i th

azidothymidine, a drug wi th a propen-

si ty for causing leukopenia. As a resul t,

an in tensive search for al ternat ive thera-

p i es i s underway . Much o f t he focus

has been on f l uconazo l e , the new o ra l

triazole antifungal. Althou gh optimal

therapy for cryp tococc al meningi ti s in

the HIV-infec ted pat ient remains unde-

fined, a recent, large multicenter trial

determined f luconaz ole to be a suitable

al ternative to am photer icin B a s a

pr imary thera py (30) . Addi t ional

ev idence sugges t s t ha t f l uconazo l e may

also be a usefu l suppressive therapy in

chronical ly infected individuals (31) .

L a b o r a t o r y D i a g n o si s

Defini t ive d iagnosis , based on the

morp hologic an d physiolo gic features

des crib ed earl ier in this article, is read-

i ly accompl i shed by r ec overy o f

C . n eo

f o r m a n s f rom CS F, b lood , o ther body

fluids, or t i ssue. The organism is non-

fast id ious, wi l l grow at 25°C or 37°C,

and can be cu l ti va t ed on m os t rou ti ne

fungal media. B eca use the organism is

var iably sensi t ive to cyclohexim ide, se-

lect ive med ia should be avoided. Pr i-

ma ry growth usua l ly occu rs within 48

to 72 h; c onsequ ent ly , the organisms

ma y be detec ted dur ing rout ine bacter io-

l og ic wo rkup o f spec imens . Recov ery

f rom b lood can be ach i eved wi th mos t

0196-4399/92/ 0.00 + 03.00 179

linical MicrobiologyNewsletter 14:23,1992 © 1992 Elsevier Science Publishing Co., Inc.

Page 4: Cryptococcus neoformans 1992

8/19/2019 Cryptococcus neoformans 1992

http://slidepdf.com/reader/full/cryptococcus-neoformans-1992 4/5

T A B L E 1 . C o m p a r i s o n o f l a b o r a t o r y f e a t u r e s o f c r y p t o c o c c a l m e n i n g i t i s i n

p a t ie n t s w i t h a n d w i t h o u t A I D S

Patients

CSF With AIDS Without AIDS

High opening pressure >65% >65%

Low glucose < 25% -50%

High protein ~50% >90%

White-cell count >20hnm 3 <30% >70%

Pleoeytosis mild or absent present

India -ink positiv e >80% <_.50%

Number of yeasts +++ +

Antigen-positive 90--100% (high titer ) >9 0%

Blood culturo--positive -50% <50%

Serum antigen-positive 98-100% ~_50%

aMo dified from referen ce 4.

ava i l ab le b lood cu l tu re me thodo log ie s ,

bu t s ome s tud ie s have s how n the s upe -

r io r pe r fo rm ance o f ly s i s -cen t r i fuga t ion

( 32 ). T h e B A C T E C 4 6 0 a n d 6 6 0 s y s -

t ems (B ec ton-Dick ins on Diagnos t i c

I n s t ru m e n t S y s t e m s , T o w s o n , M D ) ,

w h i c h m e a s u r e g r o w t h r a d io m e t r ic a U y

and by in f ra red s pec t ros copy , re spec -

t ive ly , m ay oc cas iona l ly fa i l t o de tec t

the p re s ence o f C . n e o f o r m a n s in the

b lood cu l tu re bo t t l e de s p i t e g rowth o f

the o rgan i s m in the m ed ia (33 ) .

T h e m i c r o sc o p i c e x a m i n a t i o n o f

C S F mixed w i th Ind ia ink i s a t r ad i-

t i on a l m e t h o d f o r r a p i d , p r e s u m p t i v e

iden t i f i c a t ion o f C . n e o f o r m a n s . T h e

te s t s u f fe r s f rom a l a ck o f s ens i t iv i ty

a n d s p e c i f ic i t y a n d t h e n e e d t o e x a m i n e

l a r ge v o l u m e s o f C S F . E v e n w h e n e x -

a m i n e d b y e x p e r i e n c e d p e r so n n e l , t h e

te s t is pos i t ive in on ly 50% of pa t i en t s

wi th c ryp toc occa l men in g i t i s (22 ).

T he de ve lopm en t o f l a tex pa r t i c l e

agg lu t ina t ion (L PA) fo r the de tec t ion o f

C . n e o f o r m a n s caps u la r po lys accha r ide

i n C S F a n d s e r u m o f f e r e d a s i g n i fi c a n t

i m p r o v e m e n t f o r t h e r a p id d i a g n o s i s o f

c ryp tococca l men ing i t i s . In i t i a l s pec i f i c -

i ty p rob lems , pa r t i cu la r ly in s e rum , due

to in t e r fe r ing s ubs tances s uch a s rheu-

m a t o i d f a c t o r, h a v e b e e n r e s o l v e d b y

p r e t re a t m e n t o f s p e c i m e n s w i t h p r o n a s e

(34) . C ur ren t ly , L P A i s e s t ima ted to

have a s ens i t iv i ty g rea te r than 90% fo r

the d iagnos i s o f c ryp tococc a l men ing i -

t is (22). Fa lse pos i t ives are un usual . Re-

cen t ly , how eve r , L PA c ros s - reac t iv i ty

has been repor t ed in pa t i en t s w i th d i s -

s emina ted in fec t ions w i th T r i c h o s p o r o n

b e i g e l i i

(35) . A no the r repor t de s c r ibed

a fa l s e -pos i t ive re s u l t l i nked to con tami -

na t ion o f C SF wi th s yne re s i s f lu id (36 ) .

Ove ra l l , howeve r , c ryp tococca l L PA i s

cons ide red the m os t r e l i ab le s e ro log ic

t e s t fo r the d iagnos i s o f a funga l d i s ea s e .

C e reb ros p ina l f lu id s tud ie s in HIV-

in fec ted pa t i en ts w i th c ryp tococca l

men ing i t i s o f t en revea l the p re s ence o f

l a rge numbers o f yea s t s in the abs ence

o f a n i n f l a m m a t o r y r e sp o n s e a n d I n d i a

ink p repa ra t ions ma y be pos i t ive in

ove r 80% of cu l tu re -pos i tive ca s e s

(1 -4 , 22 ) . E x t rem e ly h igh L PA t i t e r s ,

pa r t i cu la r ly in s e rum, ma y occur . T he

labora to ry s hou ld be a l e r t ed to the pos -

s ib i l it y o f a p rozone reac t ion an d the

need to inc lud e appropr i a te d i lu t ions o f

the s pec im en . Pe rs i s t en t ly e l eva ted s e -

rum an t igen t i t e rs a re com m on (2 , 4 ,

22 ) , a l thoug h the c l in i ca l s ign i f i c ance i s

unc lea r . F ina l ly , t he inc lus ion o f s e r i a l

L P A s e r u m a n d C S F t it e rs i n t h e e v a l u -

a t ion o f pa t i en t s s ub jec ted to nove l

t rea tmen t p ro toco l s w i l l p robab ly c l a r-

i fy any p rognos t i c va lue a s s oc ia t ed

with the tes t .

S u n n n a r y

In the i r z ea l t o en l igh ten c l in i ca l

c o l l e a g u e s o n t h e i m p o r t a n c e o f f u n g a l

p a t h o g e n s i n t o d a y ' s p a n t h e o n o f i n f e c-

t ious d i s ea se , med ica l my co log i s t s a re

s om e t imes d r iven to a f l a i r fo r the d ra -

mat ic . In 1970, Aje l lo (37) suspected

tha t the p reva lence o f c ryp tococcos i s

w a s m u c h h i g h e r t h a n t h e c u r r e n t in f o r -

mar ion ind ica ted . He de s c r ibed c ryp to -

c o c c o s i s a s t h e s l e e p in g g i a n t a m o n g

s y s t e m i c m y c o s e s. I n 1 9 78 , K a u f m a n n

a n d B l u m e r (2 7 ) o f t h e C D C c o m p i l e d

s e ro log ic da ta on the d i s ea s e and p ro -

c l a i m e d c r y p t o c o c c o s is t h e a w a k e n i n g

g i a n t . T h e p r o p h e c y o f th e m e t a p h o r,

f rom a 1992 pe rs pec t ive , is unne rv ing .

T h e g i a n t i s i n d e e d w i d e a w a k e a n d a

f e a r s o m e c o n t e m p o r a r y o f s y s t em i c m y -

coses .

References

1. Chuck , S. L. and M. A. Sande. 1989. In-

fections with Cryptococcus neoformans

in the acquired immuno deficiency syn-

drom e. N. Eng l. J. Med . 321:794--799.

2. Clark,R. A. et aL 1990. Speclnun of

Cryptococcus neoformans infection n 68

patients with hum an imm unodeficiency

virus. Rev . Infect. Dis. 12:768--777.

3. Eng, R. H. K. et al. 1986. Cryptocx ~cal

infections in patients with acquired im-

munodeficiency syndrome. Am . J.

Med. 81:19-23.

4. Vand epitte, J. 1990. Clinical aspects of

cryptococcosis in patients with AIDS,

p. 115-122. In H. Vanden Bossche et

al. (ed.), Myc oses in A IDS patients.

Plenum Press, New York.

5. Kwon-Chung, K. J. 1975. A new genus,

FilobasidieUa, the perfect state of Cryp-

tococcus neoformans. Mycologia

67:1197-1200.

6. McGinnis, M. R. 1980. Laboratory

handbook of m edical mycology. Aca-

demic Press, New York.

7. Kw on-Ch ung, K. J. et al. 1982. Im-

proved diagnostic medium fo r separa-

tion of Cryptococcus neoformans var.

neoformans (serotypes A and D) and

Cryptococcus neoformans var. gatt i i

(serotypes B and C). J. Clin. Microb iol.

15:535-537.

8. Vilgalys, R. and M. Hester. 1990.

Rapid genetic identification and map-

ping o f enzym atically am plified ribo-

somal DNA from several Cryptococcus

species. J. Bacteriol. 172:4238--4246.

9. Varma, A. and K. J . Kwon-Chung.

1989. Restriction fragmen t polymor-

phism in mitochondrial DNA o f Crypto-

coccus neoformans. J. Gen. Microbiol.

135:3353--3362.

10. Perfect, J. R. et al. 1989. Separation of

chromosomes of Cryptococcus neofor-

roans by pulsed field gel electrophore-

sis. Infect. Imm un. 57:2624-2 627.

11. Emm ons, C. W. 1955. Saprophytic

sources of Cryptococcus neoformans as-

sociated with the pigeon Calumba

livia). Am . J. Hyg. 62:227-232.

12. Littman, M. L. and R. Borok. 1968. Re-

lation of the pigeon to cryptococ cosis:

natural carrier state, heat resistance, and

survival of Cryptococcus neoformans.

Mycopathologia 35:329-345.

13. Ellis, D. H. and T. J. Pfeiffer. 1990.

180 0196-4399/92/$0.0003.00 © 1992ElsevierSciencePublishingCo., nc. ClinicalMicrobiologyNewsletter14:23,1992

Page 5: Cryptococcus neoformans 1992

8/19/2019 Cryptococcus neoformans 1992

http://slidepdf.com/reader/full/cryptococcus-neoformans-1992 5/5

E c o l o g y , l i f e c y c l e, a n d i n f e c ti o u s

p r o p a g u l e o f

Cryptococcus neoformans.

L a n c e t 3 3 6 : 9 2 3 - 9 2 5 .

14 . E l l i s , D . H . a n d T . J . P fe i f f e r . 1990.

N a t u r a l h a b i ta t o f Cryptococcus neofor-

mans va t. gattii.

J . C l in . Mic robio l .

2 8 : 1 6 4 2 - 1 6 4 4 .

1 5 . K w o n - C h u n g , K . J . a n d J . E . B e n n e t t .

1984 . Epide nu o log ic d i f f e r e nc e s be -

t w e e n t w o v a r i e t i e s o f Cryptococcus

neoformans. A m . J . E p i d e m i o l .

1 2 0 : 1 2 3 - 1 3 0 .

16 . R ina ld i , M. G . e t al . 1986 . Se ro ty pe s of

Cryptococcus neoformans in pa t i e n t s

w i th A ID S . J . I n fe c t . D i s . 153:642 .

17 . C la nc y , M . N . e t a l. 1990 . I so la t ion of

Cryptococc us neoformans var. gattii

f r o m a p a t i e n t w i th A I D S i n s o u t h e r n

Ca l i forn ia . J . I n fe c t . D i s . 161:809 .

18 . P fe i f f e r , T . a nd D . E l li s . 1991 . Envi ron -

m e n t a l i s o l a t io n o f

Cryptococcus neo-

formans gattii from Ca l i forn ia . J . I n fe c t .

D i s . 1 6 3 : 9 2 9 - 9 3 0 .

19. Koz el , T. R. and E. C. Gotschl ich. 1982.

T h e c a p s u l e o f Cryptococ cus neoformans

pa s s ive ly inh ib i ts pha goc y tos i s o f the

y e a s t b y m a c r o p h a g e s. J . I m m u n o l .

129:1675-1679.

20 . H e nd e r son , D . K . e t a l . 1986 . Tole ra nc e

t o c r y p t o c o c c a l p o l y s a c c h a r i d e i n c u r e d

c rypto c oc c o s i s pa ti e n t s : f a i lu re o f a n t i -

b o d y s e c r et i o n i n v i tr o . C l i n . E x p . I m -

m u n o l . 6 5 : 6 3 9 - 6 4 6 .

2 1 . K w o n - C h u n g , K . J. a n d J . C . R h o d e s .

1 9 8 6. E n c a p s u l a t i o n a n d m e l a n i n f o r m a -

t ion a s ind ic a tor s o f v i ru le nc e in Crypto-

coccus neoformans. I n f e c t. I m m u n .

5 1 : 2 1 8 - 2 2 3 .

22 . D ia m ond , R . D . 1990 .

Cryptococcus

neoformans

p . 1 9 8 0 - 1 9 8 9 . I n G . L .

M a n d e l l , R . G . D o u g l a s , a n d J . E . B e n -

ne t t ( e d . ) , P r inc ip le s a nd pra c t i c e o f in -

f e c t ions d i s e a se s . Churc h i l l

L i v i n g s t o n e , N e w Y o r k .

2 3 . K h a k p o u r , F . R . a n d J . W . M u r p h y .

1987 . Cha ra c te r i z a t ion of a th i rd-orde r

s u p p r e s s o r T - c e l l ( T ,3 ) i n d u c e d b y c r y p -

t o c o c c a l a n t i g e n (s ) . I n f e c t . I m m u n .

5 5 : 1 6 5 7 - 1 6 6 2 .

2 4 . L i t t m a n , M . L . a n d L . E . Z i m m e r m a n .

1956 . Cryptoc oc c os i s ( to ru los i s ) . G rune

a n d S t r a t to n , N e w Y o r k .

25 . L i t tma n , M . L . a nd J . E . W a l te r . 1968 .

Cryptoc oc c os i s : Cur re n t s t a tus . A m. J .

M e d . 4 5 : 9 2 2 - 9 2 8 .

26 . U . S . Ce nte r fo r D ise a se Cont ro l . 1976 .

A n n u a l s u p p l e m e n t , s u m m a r y . M o r b i d .

M o r t a l . W e e k l y R e p . 2 4 : 1 - 6 2 .

2 7 . K a u f m a n , L . a n d S . B l u m e r . 1 9 7 8 .

C r y p t o c o c c o s i s : t h e a w a k e n i n g g i a n t , p .

1 7 6 - 1 8 2 . In P r o c e e d i n g s o f t h e f o u r t h

i n t er n a t io n a l c o n f e r e n c e o n t h e m y c o -

se s . W. H . O . , Wa shing ton , I ) (2

28 . Ce nte r s fo r D ise a se Cont ro l . 1992 .

T h e s e c o n d 1 0 0 , 0 0 0 c a s e s o f a c q u i r e d

i m m u n o d e f i c ie n c y s y n d r o m e - - U n i t e d

S t a t es , J u n e 1 9 8 1 - D e c e m b e r 1 9 9 1 .

Morbid . Mor ta l . We e kly Re p . 41 :28- -29 .

29 . Be nn e t t , J. E . e t a l . 1979 . A c om pa r i so n

o f a m p h o t e r i c i n B a l o n e an d c o m b i n e d

w i t h f l u c y t o s i n e i n t h e t r e at m e n t o f

c ryp toc oc c a l me ningi t i s . N . Engl . J .

M e d . 3 0 1 : 1 2 6 - 1 3 1 .

30 . Sa a g , M . S . e t a l . 1992 . Com pa r i so n of

a m p h o t e r ic i n B w i t h f l u c o n a z o l e i n th e

t r e a tm e n t o f a c u t e A I D S - a s s o c i a t ed

c r y p t o e o c c a i m e n i n g i t i s . N . E n g l . J .

M e d . 3 2 6 : 8 3 - 8 9 .

31 . Boz z e t t e , S . A . e t a l . 1991 . A p la c e bo -

c o n t m n e d t r i a l o f m a i n t e n a n c e t h e r a p y

w i t h f l u c o n a z o l e a l~ e r tr e a t m e n t o f c r y p -

t o c o c c a l m e n i n g i t i s i n t h e a c q u i r e d i m -

m u n o d e f i c i e n c y s y n d r o m e . N . E n g l . J.

M e d . 3 2 4 : 5 8 0 - 5 8 4 .

32. Bil le ,

J. c t

a l . 1983 . Eva lua t ion of a

l y s i s -c e n t r i fu g a t i o n s y s t e m f o r r e c o v e r y

o f y e a s t s a n d f d a m e n t o u s f u n g i f r o m

blood . J . C l in . Mie rob io l . 18 :469- -471 .

33 . Rob inson , P . G . e t a l . 1987 . Fa i lu re o f

t h e B A C T E C 4 6 0 r a d i o m e t er t o d e te c t

Cryptococcus neoformans f u n g e m i a in

a n A ID S pa t i e n t . A m. J . C l in . Pa tho l .

8 7 : 7 8 3 - 7 8 6 .

34 . S toc k ma n, L . a nd G . D . Rob e r t s . 1983 .

S p e c i f i ci t y o f t h e l a t e x t e s t f o r c r y p t o -

c o c c a l a n t i g en : a r a p i d , s i m p l e m e t h o d

for e l imina t ing in te r f e re nc e f a c tor s . J .

C l i n . M i e r o b i o l . 1 7 : 9 4 5 - 9 4 7 .

35 . M c M a nus , E . J . a nd J . M. Jone s . 1985 .

D e t e c t i o n o f a

Trichosporon b eigelff an-

t i ge n c ros s - r e a c t ive w i th

Cryptococcus

neoformans c a p s u l a r p o l y s a c c h a r i d e i n

s e r u m f r o m a p a t i e n t w i t h d i s se m i n a t e d

Trichosporon i n f e c t ion . J . C l in . Mic ro-

b io l . 2 1 : 6 8 1 - 6 8 5 .

3 6 . B o o m , W . H . e t a l . 19 8 5 . N e w c a u s e fo r

f a l s e -pos i t ive r e su l t s w i th the c ryp toc oc -

c a l a n t ige n t e s t by l a t e x a gglu t ina t ion .

J . C li n . M i c r o b i o l . 2 2 : 8 5 6 - 8 5 7 .

3 7 . A j e l l o , L . 1 9 7 0. T h e m e d i c a l m y c o b i -

o log ic a l i c e be rg , p . 3 -12 . In Pan Ameri-

c a n H e a l t h O r g a n i z a t i o n , p r o c e e d in g s

o f t h e i n t er n a t io n a l s y m p o s i u m o n t h e

m y c o s e s . W H O , W a s h in g t o n , D C .

C a s e R e p o r t s

ctinomyces naeslundii

ac t eremia

E d w a r d K . C h a p n i c k , M . D .

J e r e m y D . G r a d o n , M . B . , B . S .

M i c h a e l L e v i , S c . D .

L a r r y I . L u t w i c k , M . D .

Division of Infectious Diseases

Department of Internal Medicine and

Microbiology Laboratory

Department of Pathology

Maimonides Medical C enter

Brooklyn NY 11219

Ac t inomyces naes lundi i i s a c o m p o -

n e n t o f n o r m a l h u m a n m o u t h f l o r a. I t

w a s f i rs t c h a r a c t e r i z e d a s a p a t h o g e n i n

1 9 6 9 b y C o l e m a n e t a l. ( 1 ), w h o r e -

porte

t h r e e b l o o d c u l t u r e i s o l a t e s o f

t h i s o r g a n i s m . A l i t e r a t u r e s e a r c h f a i l e d

t o d i s c o v e r a n y o t h e r c a s e s o f b a c t e r e -

m i a c a u s e d b y t h is o r g a n i s m s u b -

s e q u e n t t o t h i s 1 9 6 9 p u b l i c a t i o n .

C a s e R e p o r t

T h e p a t i e n t w a s a 7 1 - y r - o l d m a l e

w i t h a h i s t o r y o f g a s t ri c c a r c i n o m a i n -

i t ia U y d i a g n o s e d a n d t r e a te d w i t h c h e -

m o t h e r a p y i n th e S o v i e t U n io n . H e w a s

a d m i t t e d t o o u r h o s p it a l c o m p l a i n i n g o f

a b d o m i n a l p a i n a n d v o m i t i n g . A C T

s c a n r e v e a l e d a t h i c k e n e d g a s t r ic w a l l

w i t h o u t h e p a t i c m e t a s t a s e s . T h e p a t i e n t

u n d e r w e n t r a d i c a l e s o p h a g o g a s t r e c -

t o m y , s p l e n e c t o m y , a n d R o u x - e n - Y

e s o p h a g o j e j u n o s t o m y o n h o s p i ta l d a y 8 .

T h e i m m e d i a t e p o s t o p e r a t i v e c o u r s e

w a s u n e v e n t f u l. P a t h o l o g i c e x a m i n a -

t i o n r e v e a l e d i n f d t r a ti n g , m o d e r a t e l y

d i f f e r e n t i a t e d a d e n o c a r e i n o m a a r i s i n g

f r o m t h e p r o x i m a l s t o m a c h a n d e x t e n d -

i n g t o t h e e s o p h a g e a l m a r g i n a n d p e r i -

g a s t r i c f a t .

T h e p a t i e n t d i d w e l l u n t i l t h e p o s t o p -

e r a ti v e d a y 1 4 , w h e n h e d e v e l o p e d v o m -

i t in g a n d a t e m p e r a t u r e o f 1 0 2 ° a n d w a s

Clinical MicrobiologyNewsletter14:23,1992 © 1992 Elsevier Science PublishingCo., Inc. 0196-4399/92/ 0.00 + 03.00 18 |