Diagnosis of pulmonary aspergillosis ignoring allergy

1
Diagnosis of pulmonary aspergillosis(ignoring
allergy)

• David W. Denning
• Wythenshawe Hospital
• University of Manchester

2
Conceptual framework
Chronic inflammation and fibrosis
Vascular invasion, necrosis, dissemination
Granulomas, acute inflammation, central necrosis
Aspergilloma - CCPA - CNPA/subacute IPA - acute
IPA
3
Testing performance?
Aspergilloma - CCPA - CNPA/subacute IPA - acute
IPA
Culture /- /- /- /- Antigen
- - - Glucan /- ?
? /- Antibody ?
- PCR (resp) ? ? ? PCR
(blood) -? -? -? /-
4
Testing performance?
Pulmonary defect innate immune
defect corticosteroids neutrophil
defect neutropenia multiple defects
Culture /- /- /- /- Antigen
- - - Glucan /- ?
? /- Antibody ?
- PCR (resp) ? ? ? PCR
(blood) -? -? -? /-
5
Invasive aspergillosis in ICU

• 127 of 1850 (6.9) consecutive medical ICU
  admissions with IA or colonisation
  (micro/histol).
• 89/127 (70) did not have haematological
  malignancy
• 67/89 proven/probable IA, 33 of 67 (50) COPD
• In 67
• Culture ve in 56/67 (84)
• Aspergillus antigen ve 27/51 (53)

Meersemann et al, Am J Resp Med Crit Care
2004170621.
6
Testing performance?
Pulmonary defect innate immune
defect corticosteroids neutrophil
defect neutropenia multiple defects
Culture () /- /- /-
/- Antigen (-) - -
Glucan (/-) ? ?
/- Antibody () ? - PCR
(resp) () ? ? ? PCR
(blood) -? -? -? /-
7
Organism/antigen/marker performance will vary by
fungal load (in lung, but not necessarily
blood) and possibly treatment
8
Aspergillus Antigen in BAL

• 13/17 (76) in acute leukaemia with CT
  abnormality
• 17/17 (100) in neutropenic patients before
  antifungal Rx, 0 after 3d antifungal therapy
• 20/20 (100) in haem-onc pts with IPA
• 37/49 (76) in HSCT haem-onc with IPA
• 6 of 11 (55) immunocompromised (8 of 11 ve by
  PCR)
• 5/20 (25) in suspected IFIs

Becker, Br J Haem 2003121448 Sanguinetti, JCM
2003413922 Musher, JCM 2004425517.
9
Organism/antigen/marker performance will vary by
fungal load (in lung, but not necessarily
blood) and possibly treatment Antibody and
imaging performance will be more independent of
organism load to the same extentAntibody takes
time to form (and tests are not standardised)
10
Contribution of CT scans and antigen testing to
rapid diagnosis of IA
Caillot et al, J Clin Oncol 200119253
11
Unequivocal Halo sign surrounding a nodule
Halo
Small vessel angioinvasion
Herbrecht, Denning et al, NEJM 2002347408-15.
12
CT scan enlargement of IA on treatment despite
good outcomes
Caillot et al, J Clin Oncol 200119253
13
Contribution of CT scans and antibody testing to
rapid diagnosis of IA
Caillot et al, J Clin Oncol 200119253
(unpublished data)
14
Test sensitivity importantMicroscopy
methodologyCulture versus PCRHistopathology
versus culture
15
Test sensitivity importantMicroscopy
methodologyCulture versus PCRHistopathology
versus culture
16
Microscopy
Ruchel R, www.aspergillus.man.ac.uk/images
17
Test sensitivity importantMicroscopy
methodologyCulture versus PCRHistopathology
versus culture
18
PCR detection of Aspergillus (rRNA target)
Prospective study of 197 bronchial washes in 176
patients (most leukaemia, most lung infiltrates
on X-ray) Results
Immunocom-promised pts IA not IA
normal pts IA not IA
ve PCR
-ve PCR
Positive predictive value (PPV) - 83.8 in at
risk patients Negative predictive value (NPV) -
98.1 in at risk patients
Buchheidt Br J Haematol 2002116803-811.
19
PCR detection of Aspergillus (rRNA target)
Immunocom-promised pts IA not IA
normal pts IA not IA
ve PCR
-ve PCR

• Proven, probable and possible was 12, 13 and 5,
  of whom all proven and probable cases had
  abnormal chest CT scans,
• 11 had positive cultures from BAL (9) or sputum
  (2), 14 had positive cytology from BAL or sputum
  but were culture negative,
• 3 had positive galactomannan antigen tests and 3
  had histological confirmation.
• 20 of the 31 patients died.

Buchheidt Br J Haematol 2002116803-811.
20
Comparison of BAL antigen and real-time PCR
Culture Antigen PCRProven/probable IA All
haem malignancy 6/20 20/20 18/20
Sanguinetti, Clin Microbiol. 2003413922-5.
21
Additional sensitivity will allow species
detection and possibly resistance detection on
culture negative clinical specimens
Real time PCR to distinguish Aspergillus
species A. terreus resistant to amphotericin B
Perlin , unpublished
22
Bronchoalveolar lavage for diagnosis of invasive
pulmonary aspergillosis

• positive result in all those with
• definite or probable aspergillosis

Patients BAL BAL Either Reference culture cytolog
y or both Acute leukaemia - - 50 Albeda,
1984 Leukaemia 23 53 59 Kahn, 1986 Leukaema 0 0 0
Saito, 1988 Leukaemia, BMT, 40 64 67 Levy, 1992
Oncology BMT focal 0 0 0 McWhinney,
diffuse 100 0 100 1993 All 41 83 100 Tarrand,
2003 AlloBMT 17 0 17 Roychowdhury, 2006
23
Test sensitivity importantMicroscopy
methodologyCulture versus PCRHistopathology
versus culture/antigen
24
Invasive aspergillosis in ICU

• 127 of 1850 (6.9) consecutive medical ICU
  admissions with IA or colonisation
  (micro/histol).
• 89/127 (70) did not have haematological
  malignancy
• 67/89 proven/probable IA, 33 of 67 (50) COPD
• In 67
• Culture ve in 56/67 (84)
• Aspergillus antigen ve 27/51 (53)
• Autopsy ve for hyphae in 27/41 (66)

Meersemann et al, Am J Resp Med Crit Care
2004170621.
25
Respiratory samples ve for Aspergillus in ICU
Vandewoude KH. Critical Care 200610R31
26
Respiratory samples ve for Aspergillus in ICU
Vandewoude KH. Critical Care 200610R31
27
www.aspergillus.man.ac.uk