early diagnosis with the aid of serological markers - escmid

Early diagnosis with the aid of

serological markers

Georgia Vrioni

Medical School, University of Athens

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

02/03/2012 Problems and progress in the diagnosis of IFIs

Diagnostic methods for IFIs

Conventional methods • direct microscopic examination • culture

Non-culture-based methods

Serologic methods

Molecular methods

Histopathology Radiology

β-D glucan galactomannan cryptococcal capsular polysaccharide

Microbiological Non-microbiological

PCR

2

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Diagnosis of invasive fungal infections

Diagnosis is difficult:

symptoms non-specific

sensitivity of culture is low

Early diagnosis is important for survival

Techniques to improve timely diagnosis have focused on the detection of circulating markers released by the fungus


3

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


Better markers = better strategies

Sequelae Full blown disease

Signs and symptoms Markers No disease

High risk patients (chemo, ICU,…)

High risk host on antibiotics with fever

Remember RISK hosts and factors

Prophylaxis Pre-emptive Empirical Therapy

Asymptomatic

Colonization

4

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Which are the characteristics of an ideal antigenic marker for IFIs?


The ideal antigenic marker for IFIs should

not be present too transiently,

be associated with infection rather than colonization,

be conserved within the fungal species of interest,

not cross-react with other human and microbial antigens, and

be present sufficiently early for the starting of antifungal therapy.

Tests for this antigen should

be adaptable to formats that can be used in routine clinical laboratories,

be easy to perform, and

not be subject to significant interlaboratory variation.

5

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Fungus Antigen, antibody, enzyme,

metabolite Clinical specimen

C. neoformans Glycuronoxylomannan* CSF, serum, urine

Aspergillus Galactomannan (GM)* Serum, BAL

(CSF, urine??)

Candida Mannan, antimannan* Serum, CSF

Candida Enolase Serum

Candida Anti-enolase & antibodies

against other intracytoplasmic antigens

Serum

Candida D-arabinitol Serum

Aspergillus & Cryptococcus

Mannitol Serum

Fungi other than Zygomycetes and C. neoformans

(1,3)-β-D-glucan* Plasma/serum

* Used in routine diagnosis

Serologic methods

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Glycuronoxylomannan

Cryptococcal capsular polysaccharide Ag Prevost E et al., JCM 1978;8:529

Yeo SF, Wong B. Clin Microbiol Rev, 2002

Latex agglutination (polyclonal IgG) (Pastorex Crypto Plus)

serum, CSF, urine, BAL

Sensitivity 93-100%

Specificity 93-98%

False (+):

Rheumatoid factor

Disseminated trichosporonosis

Capnocytophaga canimorsus septicemia

Malignancy

False (-):

Prozone-like effect: can be corrected by dilution of the specimen or pronase treatment

LA (monoclonal IgM) (Murex):

Eliminates false (+) reactions with RF

Lower sensitivity

EIA (a polyclonal capture system and a monoclonal detection system) [Premier Cryptococcal Ag (Meridian)]:

• Serum, CSF, urine • Sensitivity and specificity as Pastorex LA • Advantages over LA:

• does not react with rheumatoid factor, • can be run with a fairly large number of samples, and • gives fewer false (+) reactions

High concordance between all the tests used (LAT and EIA) Babady et al. (2009); Saha et al. (2008)

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Dolan Champa Saha J Med Microbiol 2009;58:1098–1105

Aim: comparative study of • conventional methods and • rapid diagnostic methods

latex agglutination test (LAT), enzyme immunoassay (EIA) and PCR.

Material: 359 samples from 52 patients with cryptococcosis (31 HIV-pos & 21 HIV-neg) and 30 negative controls.

Evaluation: CSF, serum and urine samples separately

02/03/2012 Problems and progress in the diagnosis of IFIs 8

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

CSF

Serum

Urine Although the fungal load in urine was low, the presence of cryptococcal Ag in urine was sufficient to be detected by serological methods.

LAT, EIA and PCR: positive even when culture was negative in samples of low inoculum or in patients on antifungal treatment Sensitivities of LAT, EIA and PCR are comparable Higher specificity of EIA than LAT

Dolan Champa Saha J Med Microbiol 2009;58:1098–1105

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Definitions


In the case of Cryptococcus neoformans

detection of capsular antigen in CSF (or a positive result of an India ink preparation of CSF) was considered sufficient to establish a diagnosis of proven cryptococcosis.

De Pauw et al., CID 2008 46:1813–21

10

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Recommendations


Serum antigen to diagnose

disseminated cryptococcosis (higher sensitivity in HIV-pos vs HIV-neg)

Good evidence (A II)

CSF antigen to diagnose cryptococcal meningitis

Good evidence (A II)

Serum antigen to diagnose pulmonary cryptococcosis

Moderate evidence (from opinions, clinical experience) (B III)

Use of baseline antigen titres for prognosis

Moderate evidence (B III)

Use of serum or CSF antigen kinetics (titres) to assess response to treatment

Poor evidence (C III)

11

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Detectable mannanemia: Invasive candidiasis

Less likely to be present in patients with transient or central

venous catheter-related candidemia

Rapid clearance from serum 40% of patients from whom multiple serum samples were

available, 11% of patients from whom only one sample was

available (Sendid, JCM, 1999)

Repeat serum sampling (2-3/weak)

Improve sensitivity and specificity Combination of two assays (mannan & anti-mannan)

Detection in sterile samples

CSF: specificity 100% if C. albicans

Yeo SF and Wong B, Clin Microbiol Rev, 2002

Kedzierska A et al., Eur J Clin Microbiol Infect Dis 2007

12

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

13

Platelia Candida (ELISA, Bio-Rad):

Monoclonal antibody ΕΒ-CA1

Detection threshold = 0.25 ng/ml

Better sensitive than LA test, but steal low

(40%)

Rapid clearance of the patients’ sera

Similar specificity (98%) Sendid et al., 1999, JCM, 37: 1510-1517

Pastorex Candida (LA, Bio-Rad):

Monoclonal antibody ΕΒ-CA1

Detection threshold = 2.5 ng/ml

Sensitivity 28%

Specificity 100% Sendid et al., 1999, JCM, 37: 1510-1517

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Problems and progress in the

diagnosis of IFIs 14

Positive result

> / = 10 AU

Positive result

> / = 0.5ng/ml

Platelia

Candida

Ab/Ac/Ak,

(Bio-Rad)

Platelia

Candida Ag,

(Bio-Rad)

Anti-mannan and Mannan

Sendid B, J

Med Microbiol

2002;51:433

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Sendid

B.

et

al,

JCM

, 1999

Mannan and anti-mannan

Lunel Diagn Microbiol Infect Dis 2009; Ellis J Med Microbiol 2009; Sendid Clin Vaccine Immunol 2008;

Oliveri Clin Microbiol Infect 2008; Alam BMC Infect Dis 2007; Fujita J Med Microbiol 2006;

Prella Diagn Microbiol Infect Dis 2005; White J Clin Microbiol 2005; Sendid J Clin Microbiol 2004;

Sendid J Clin Microbiol 2003; Sendid J Med Microbiol 2002; Persat Mycoses 2002;

Yera Eur J Clin Microbiol Infect Dis 2001; Sendid J Clin Microbiol 1999.

Mannan Anti-mannan Combination

Per patient 60% (31-100) 60% (46-100) 89% (75-100)

Per sample 53% (17-100) 60% (39-100) 83% (75-100)

Sensitivity, median (range)

Use of both

enzyme

immunoassays

may be useful for

the routine

diagnosis of

candidiasis

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Sensitivity of Ag & Ab was the highest for C. albicans

and the lowest for C. parapsilosis or C. krusei.

16

Platelia Candida Ag test is based on the use of a monoclonal antibody EB-CA1,

which recognizes a mannopentose epitope of C. albicans.

This epitope has also been found at high levels in C. glabrata and C. tropicalis, but

at lower levels in C. krusei, C. kefyr and C. parapsilosis.

Sendid et al. 2002; Jacquinot et al. 1998; Rimek et al. 2003

Mannan Anti-mannan Mannan & anti-mannan

C. albicans 62% 67% 100%

C. glabrata 58% 83% 83%

C. tropicalis 70% 60% 80%

C. parapsilosis 30% 10% 40%

C. krusei 25% 38% 50%

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Serum antigen positivity significantly preceded the positive blood

culture result

In one study 73% of patients had one test positive before the blood

culture results (at least 2 days and in some patients up to 15 days)

Yera H, Eur J Clin Microbiol Infect Dis 2001;20:864

17

Lunel, Mennink-Kersten et al. 2009;

Oliveri, Trovato et al. 2008;

Prella, Bille et al. 2005;

Sendid, Poirot et al. 2002;

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Poor performance of mannan sandwich EIA in the diagnosis of IFIs

Positive M antigen testing is not included in EORTC/MSG definition

De Pauw et al., CID 2008 46:1813–21

The use of combined Ag/Ab is preferred over

Ag or Ab only for diagnosing invasive

Candida infection (ICU/surgery patients)

Moderate evidence (B II)

The combined Ag/Ab testing is useful for

supporting the diagnosis of candidemia

Poor evidence (C II)

The combined Ag/Ab testing is useful for

diagnosing hepatosplenic candidiasis

Moderate evidence (B III)

18 Mikulska et al., Critical Care 2010;14:R222

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Candida albicans germ tube

antibody CAGTA

A Spanish group has developed an antibody test against the germ-

tube structure of Candida albicans cells developing when growing in

culture or invading host tissue (C. albicans IFA IgG, Vircell, Spain).

Applying this test to various patients populations they have

observed that

this test provides a rapid and simple diagnosis of IC (an overall

sensitivity of 77-89% and a specificity of 91-100%)

patients with positive CAGTA had a better outcome than those with

negative antibodies,

detection of CAGTA in patients with invasive infections caused by

Candida species other than C. albicans may also be positive, although

titers are lower.

02/03/2012

Peman et al. Mycoses. 2009; Zaragosa et al., Clin Vaccine Immunol 2009; Moragues

et al., Enferm Infecc Microbiol Clin 2004; Zaragoza et al., Clin Microbiol Infect

2009; Pontón et al., JCM 1994; Quindós et al., Eur J Clin Microbiol Infect Dis 1990.

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


Pemán et al. BMC Infectious Diseases 2011;11:60

A prospective, cohort, observational multicentre study was

carried out in six medical/surgical ICU of tertiary-care Spanish

hospitals.

Aim: to identify the patients who could be benefited by the use of

Candida albicans Germ Tube Antibody test in critical care setting.

CAGTA test was performed twice a week if predetermined risk factors were

present, and

serologically demonstrated candidiasis was considered if the

testing serum dilution was ≥ 1:160 in at least one sample and no

other microbiological evidence of invasive candidiasis was found.

53 critically ill non-neutropenic patients (37.7% post surgery) were

included. •22 patients(41.5%) had CAGTA-positive results, none of them with positive

blood culture for Candida.

• Neither corrected colonization index nor antifungal treatment had

influence on CAGTA results.

• This finding could corroborate that the CAGTA may be an important

biomarker to distinguish between colonization and infection in these

patients.

• The presence of acute renal failure at the beginning of the study was

more frequent in CAGTA-negative patients.

• Previous surgery was statistically more frequent in CAGTA-positive

patients.

• Detection of CAGTA may be important for the diagnosis of invasive

candidiasis in surgical patients admitted in ICU.

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Galactomannan (GM antigen)

Jones B. and McLintock L, Curr Opin Infect Dis, 2003

Yeo SF and Wong B, Clin Microbiol Rev, 2002

Component of the cell wall of Aspergillus spp. Many other

filamentous fungi may have GM in their cell wall (but in

lower amount).

Heat-stable heteropolysaccharide

Detection in:

serum

BAL

tissue

bodily fluids (CSF, peritoneal fluid, urine, pericardial fluid)

GM production is proportional to fungal load

GM levels appear to have

prognostic significance

high unremitting levels (in the face of antifungal therapy) associated

with an unfavourable outcome

mostly

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


Pastorex Aspergillus (LA): detection limit 15 ng/ml

Platelia Aspergillus (ELISA): 0.5-1.0 ng/ml

More sensitive (15-20 times)

became positive earlier than LA (2-3 weaks)

remain positive after the LA had became negative

Europe: from 1995. USA: FDA cleared 2003

ELISA

Sensitivity: 29-100%

Specificity: 21-98%

FDA data Sensitivity 81%, spesificity 89%

22 Hope et al., Lancet Inf Dis 2005; Yeo et al., CMR 2002; Cuenca-Estrella M et al., JAC 2011

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

12/11/2011 23

Positive GM: mycological criterion

of probable invasive aspergillosis

detected in serum, plasma, BAL or CSF

European Organisation for the Research and

Treatment of Cancer and

Mycosis Study Group (EORTC/MSG)

(Ascioglu S., et al., CID, 2002, 34:7-14)

(De Pauw B., et al., CID, 2008, 46:1813-21)


Problems and progress in the diagnosis of IFIs

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Platelia Aspergillus: meta-analysis

Pfeiffer et al, CID, 2006; 42: 1417

Underlying

disease

Age

Choice of

cutoff values

for defining

positivity

24

Sensitivity increases in patients with hematological malignancy

(haematopoietic stem cell transplants recipients,HSCTs)

declines in solid organ transplant (SOT) recipients

Positive result ~ 8 days earlier (1-27 days)

PPV: 70-87.5%

NPV: 96.3-98.4%

•Sensitivity: ≤50% in non-neutropenic patients

The GM assay should be used only when there is a high

pretest probability of IA (in high risk populations with

neutropenia and malignancy or populations that have

undergone transplantation)

In non-neutropenic patients: a negative result or a low GM

index should not eliminate the diagnosis of IA. This limitation

calls for other microbiological tests, including analysis of BAL,

to establish a definitive diagnosis of IA. Cordonnier C et al. Clin Microbiol Infect 2009;15:81

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

GM-”cut-off” index value for serum [OD sample/OD control]

1.5

0.5

Manufacturer

FDA

EUROPE

Maertens JA et al., Clin Infect Dis 2007;44:1329

> / = 0.5 in 2 consecutive samples Highest accuracy of the test with improved PPV

0.7

Lowering the cutoff OD index from 1.5 to 0.5

the overall sensitivity by 21% (from 76.3% to 97.4%)

but

the overall specificity by 7% (from 97.5% to 90.5%).

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

False-positivity (5% in adults, 83% in neonates)

Cross-reactions:

Other fungal species (Penicillium chrysogenum, P. digitatum, Paecilomyces varioti, Geotrichum capitatum, …)

Lipoteichoic acid Bifidobacterium bifidum sp pennsylvanicum (3% in the gut of adults, 91% - 75% in the gut of breast- and formula-fed infants)

False positive antigenemia

Translocation from various food stuff-milk, rice, protein-rich food,…

Drugs (originated from fungi)

β-lactam antibiotics (pirecillin, piperacillin-tazobactam,…)

Immunoglobulins

Haemoderivatives

GM-containg solutions (Plasma-Lyte)

Immunosuppressive drugs (cyclophosphamide)

2/3/2012 26

Aquino VR. et al., Mycopathologia 2007

Cuenca-Estrella M et al., JAC 2011 Platelia GM test

Problems and progress in the diagnosis of IFIs

FDA: practice caution in using Bio-Rad Platelia Aspergillus EIA

www.fda.gov/cdrh/oivd/laboratory.html (2005)

Take serum sample before dosing (“at trough level”)

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

False-negativity (< 5%)

Prior administration of antifungals, especially prophylaxis with

intraconazole (by decreasing the fungal load)

reduced the sensitivity to 20% (vs 80% in those not receiving these drugs)

the sensitivity in BAL fluid was reduced by only 8%

Cut-off index

Inappropriate diagnostic criteria for IA:

sensitivity depends on the criteria used to diagnose IA

Inadequate frequency of galactomannan testing

4 times a day in oncology patients: variations in OD index from 0.17 to

1.15 (Racil et al., 2006)

levels should be determined immediately in patients where the

diagnosis of IA is likely to occur (Hope et al., Lancet Infect Dis

2005;5:609–22)

Severity of aspergillosis

Quantity of GM released can vary according to Aspergillus species

Higher GM concentrations: A. terreus, A. niger, A. nidulans 27

concentration 10 times of the serum

sensitivity of ELISA 50% (JCM 2008, 46: 1391-7)

Platelia GM test Aquino VR. et al., Mycopathologia 2007

Cuenca-Estrella M et al., JAC 2011

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

28

Patients received antifungal therapy

At least

2 samples (+)

J Clin Microbiol 2009; 47:129

Problems and progress in the diagnosis of IFIs 2/3/2012

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

12/11/2011 Εργαστηριακή Διάγνωση 29

GM (+)

GM (-)

Survival was significantly

better in patients who

became GM-negative

(P < 0.0001).

Cancer 2009; 115:355

In patients with leukemia and IΑ under treatment:

• GM index >1 sign of therapeutic failure Koo et al. JCM 2010;48:1255

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

30

Bronchoalveolar Lavage Fluid Galactomannan for the

Diagnosis of Invasive Pulmonary Aspergillosis in Patients

with Hematologic Diseases

Good BAL GM sensitivity (91.3%, cut-off index ≥ 1.0) in comparison with

culture and microscopy (50% and 53.3%, respectively)

BAL GM is a valuable adjunctive diagnostic tool to other conventional

microbiologic and radiologic studies. Maertens J, CID 2009; 49: 1688

GM in BAL: the optimal cut-off =/> 1.0

2/3/2012

Contribution of Galactomannan Antigen Detection in BAL

to the Diagnosis of Invasive Pulmonary Aspergillosis in

Patients With Hematologic Malignancies

GM detection in BAL (cut-off index ≥ 0.5): SEN 57.6% and SPE 95.6%

Detection of GM in BAL is complementary of serum GM testing and

mycologic evaluation of the respiratory samples for the diagnosis of IPA.

Bergeron A, Chest 2010; 137: 410

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

12/11/2011 Εργαστηριακή Διάγνωση 31

The diagnostic utility of GM in sputum for diagnosis IPA and comparison of the results with those of BAL and serum

6 patients with proven / probable IA

13 patients with possible IA

37 patients with non-IA

GM

cut-off

GM

sensitivity (%)

GM

specificity (%)

Sputum 1.2 100 62 Colonization?

BAL 0.5-1.3 67 100

Serum 0.5 83 81

The

significantly

lower

sensitivity of

BAL GM

compared with

sputum may be

due to the

extent

of dilution of

the sample…

Kimura S, Int J Hematol 2009; 90: 463 GM in sputum

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

32

GM in serum (ΑΙΙ): adult neutropenic patients undergoing intensive chemotherapy for leukemia or receiving an allogeneic stem cell transplantation (plasma C III)

combined with high resolution CT imaging,

every 3 to 4 days

a single sample: index ≥0.7

2 consecutive samples: index ≥0.5

GM in BAL (cut-off 1.0) and CSF (cut-off 0.5) (in neutropenic and non-neutropenic patients): is recommended (ΒΙΙΙ)

GM in pleural fluid, sputum or urine is insufficient to make recommendations (CIII)

Persistent GM during therapy is a poor prognostic sign (BII)

Serum serial testing in neutropenic paedriatic patients


ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

33

(1-3)-β-D-glucan

It is a homogeneous assay and does not require any washing steps.

It can be completed in ~ 2 hours


Component of the fungal cell wall (present in many fungal species)

EXCEPT Zygomycetes

EXCEPT Cryptococcus neoformans

Diagnosis of IFIs (such as candidiasis in critical ill patients, Pneumocystis pneumonia):

Serum: the only currently approved sample

(Serum that is hemolysed, lipemic, visually icteric or turbid is not suitable)

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

BD assays commercially available for diagnostic use

34

Kit product Manufacturer Availability Horseshoe

crab

species

Photometric

principle

Manufacturer’s

cut-off

Fungitell Associates of

Cape Cod

(ACC), Inc

(USA)

USA (FDA

approved)

Europe

Limulus

polyphemus Chromogenic >/= 80 pg/ml

< 60 pg/ml: neg

60-79 pg/ml:

indeterminate

Fungitec

G-MK

Seikagaku

Biobusiness

(Japan)

Japan only (collaboration

with ACC)

Tachypleus

tridentatus* Chromogenic

20 pg/ml

β-Glucan

test

Wako Pure

Chemical

Industries

Ltd. (Japan)

Japan only

Tachypleus

tridentatus*

Turbidimetric 11 pg/ml

β-Glucan

test

Mahura Corp.

(Japan)

Japan only (collaboration

with Wako)

Tachypleus

tridentatus* Chromogenic

11 pg/ml

* Tachypleus tridentatus 3-5x more reactive than Limulus polyphemus

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Pan-fungal marker

35 Problems and progress in the diagnosis of IFIs 2/3/2012

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


(1-3)-β-D-glucan

Sensitivity 50-100%

Specificity 77-100%

NPV 73-100%

PPV 44-67%

Positivity 4-14 days earlier than clinical

diagnosis (or after in some

cases)

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

37

Positive β-D glucan (in serum): mycological criterion

of probable Invasive fungal disease

other than cryptococcosis and

Zygomycoses (Rhizopus, Mucor, Absidia)

European Organization for the Research and Treatment

of Cancer and Mycosis Study Group (EORTC/MSG)

(De Pauw B., et al., CID, 2008, 46:1813-21)

Limulus

(1-3)-β-D-glucan

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

38

Odabasi et al., CID, 2004, 39:199-205

283 hematological (AML / MDS) patients

•(+) results in 70% of the patients: ~ 3 days earlier

(from 32 days before to 7 days after)

• In proven or probable IFI: ~ 10 days earlier

(from 32 days before to 2 days after )

β-D-glucan test: take more than one sample


ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

39

Koo et al. CID 2009;49:1650

Multicenter study:

1308 BG from 871 patients

228 proven / probable IFD


BG level 80 pg/mL

• Sensitivity: 64%

• Specificity: 84%

•The use of albumin, intravenous immunoglobulin or hemodialysis was

associated with false-positive results.

•Empirical systemic antifungal treatment did not reduce overall BG

sensitivity.

• BD was of greater use in patients who did not have haematological

disease.

Consideration of BG results would have increased the diagnostic certainty

to probable in 54% of possible IFD cases.

(1-3)-β-D-glucan

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


(1-3)-β-D-glucan: meta-analyses

Karageorgopoulos D et al., Clin Infect Dis 2011;52:750

Yuan Lu et al., Intern Med 2011;50:2783

15 studies, were included for the analysis (proven and probable IFD vs

possible or no IFD): Sensitivity 76%, specificity 85%

higher specificities for patients with hematological disorders and a

positive BG result with two consecutive samples

the BG results should be interpreted in parallel with clinical findings.

BDG between patients with proven or probable IFIs (excluding Pneumocystis

jirovecii infections)

16 studies: pooled sensitivity of BDG 76.8% and specificity 85.3%

Marked statistical heterogeneity

BDG has good diagnostic accuracy for distinguishing proven or probable IFIs

from no IFIs.

It can be useful in clinical practice, if implemented in the proper setting

and interpreted after consideration of its limitations.

Lamoth F et al., Clin Infect Dis 2012;54:633

Four commercial BG antigenemia assays

BG antigenemia assays for the diagnosis of IFI in hemato-oncological

patients

6 cohort studies:

The diagnostic performance of the BG assay in proven or probable IFI

was better with 2 consecutive positive test results

For 2 consecutive tests: sensitivity 49.6% and specificity 98.9%

Because sensitivity is low, the test needs to be combined with clinical,

radiological, and microbiological findings.

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

02/03/2012 Problems and progress in the diagnosis of

IFIs

41

Akira Onishi et al, J. Clin. Microbiol. 2012, 50(1):7

The diagnostic

accuracy was

significant lower in

EORTC/MCG criteria

Case-control studies

overestimate both

SEN & SPE

Fungitell was

statistically lower in

accuracy than

Fungitec G / Wako

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


Summary receiver operating characteristic (SROC) curves for Pneumocystis jiroveci pneumonia and IFI

Akira Onishi et al, J. Clin. Microbiol. 2012, 50(1):7

Heterogeneity was significant for IFI diagnosis

The diagnostic accuracy of the BG assay is high for PJP and moderate for IFI.

Because the sensitivity for PJP is particularly high, the BG assay can be used as a

screening tool for PJP.

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


(1-3)-β-D-glucan in the diagnosis of IPA

What should be the optimal cut-off of serum 1,3-β-D glucan for the

detection of IPA in patients with haematological malignancies?

JCM

2011;49:3783

Clin Microbiol Infect

2011;17: 1053

Metan G et al., Scand J Infect Dis 2011;

Cut-off of 140 pg/ml: sensitivity 85.7%, specificity 69.7%, NPV 91.3%.

Moderate performance characteristics of this test: limit its use as a

diagnostic test for IA in this population

Further and prospective investigations with more patients and serial

sampling

BG in the setting of non-surgical ICU patients is a non-invasive

diagnostic tool with efficiency, sensitivity and specificity

above 80% for the diagnosis of FP in critical patients at risk, and high NPV (93%)

BD (and GM) 4.3 days (1-10) before Aspergillus was cultured

Evidence based prospective studies are needed for further evaluation of the

usefulness of BG.

Higher cut-off levels (>180 pg/ml): specificity and sensitivity of BD to

unacceptable level

The commercially recommended cut-off: appropriate for screening purposes

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

44

J Clin Microbiol 2009; 47:129


Patients received antifungal therapy

At least

2 samples (+)

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


(1-3)-β-D-glucan in the diagnosis of IC

Int. J. Mol. Sci. 2011; 12: 5871

Critical Care 2011, 15:R249

Clin Microbiol Infect 2011; 17: 1549–1553

Clin Vaccine Immunol 2011;18:2113

BD as an aid in the diagnosis of candidemia

Τhe test results should be associated with

clinical data (and other microbiological

information)

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


False positive results may be associated with:

Hemodialysis patients (cellulose filters) Kato et al., 2001

Bacteremia, cirrhosis, enterocolitis

Patients receiving

coagulation factors / albumin / immunoglobulins Ikemura et al., 1989

IV antimicrobial therapy (beta-lactams: AMC, SAM,…)

Hemolyzed serum specimens, lipemic, or that contain bilirubin.

Contaminated specimens (gauze for desinfection at the bedside

environmental dusts-organic wastes in the lab) Nakao et al., 1997

Attention should be paid to the technical complexity of the assay

and the cost implications.

(1-3)-β-D-glucan

Monique et al., 2006; Marty et al., 2006; Metan et al., 2011

All materials (tips, tubes) and glassware used must

be free of interfering glucan.

The Fungitell assay requires rigorous attention to

technique and the testing environment.

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Screening for IFD using BD for high-risk hematological

patients with prolonged neutropenia after

chemotherapy for AL or for allogeneic HSCT

Strength for recommendation: moderate evidence to support

recommendation for use (BII)


(1-3)-β-D-glucan

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Method Indication Advantages Disadvantages

GΜ Early

detection

of

aspergillosis

2 samples

weekly

(at least)

Cut-off: 0.5

A screening test to accompany

conventional diagnostics

methods in patients at high

risk for IA

• in neutropenic adults

• in neutropenic children

• Serum value >1: sign of

therapeutic failure in adult

and children

•Aids in ruling out of IA due to

the high % of NPV

• Quantification in BAL(cut-

off>1) and in CSF (cut-off>0.5)

(useful in neutropenic and

non-neutropenic patients)

• In non-neutropenic

patients: not the same

diagnostic and prognostic

value

•Mould-active antifungal

drug therapy is one of the

factors which may have

impact on SEN

Serologic tests for the diagnosis of IFIs


ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


b-D-

glucan

Diagnosis of IFI

2 samples

weekly

(at least)

Pun-fungall marker in

critically ill patients and

in cases of PJP

•A frequency of 2 tests

per week seems an

appropriate screening

strategy increases the SPE but

decreases the SEN

•False-(+) results,

methodological concerns

•Limited experience •Less widely used than GM

•The threshold for positive

results depends on the test

which is used. •Fingitell > 80pg/ml

•Wako >7 pg/ml

•Less accuracy in

hematological patients

(significant limitation to use

as screening test)



ESCMID O

nline

Lectu

re Lib

rary

© by au

thor


Mannan

and

Anti-Mannan

Invasive

candidiasis

• Good sensitivity and

specificity in combined

use

• Limited experience

• Non-mycological

criterion

CAGTA

Invasive

candidiasis

•Diagnosis and

therapeutic monitoring

•High specificity

•Detect several Candida

species

• Limited experience

• Non-mycological

criterion

Cryptococcal

Ag

Disseminated

cryptococcosis

Cryptococcal

meningitis

•In CSF: mycological

criterion of proven

cryptococcosis

•CSF, serum, urine

•High SEN and SPE

Moderate evidence

• to diagnose pulmonary

cryptococcosis

• to prognosis

Poor evidence

• to assess response to

treatment



ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

Conclusions


IFIs are still difficult to diagnose

Criteria for proven invasive fungal disease:

Microscopic analysis / culture: sterile material

New serologic tests

may be helpful in early diagnosis, but

sensitivities may be influenced by various factors

Conventional & serological methods: together

The concomitant use of serological methods as screening tests in high risk patients may provide early diagnosis, early treatment and lower mortality rates

ESCMID O

nline

Lectu

re Lib

rary

© by au

thor

early diagnosis with the aid of serological markers - escmid

Documents