Getting to the diagnosis of aspergillosis: Tests and their interpretation

1
Getting to the diagnosis of aspergillosis Tests
and their interpretation

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

2
Aspergillus Life-cycle
www.aspergillus.man.ac.uk
3
CLASSIFICATION OF ASPERGILLOSIS
Airways/nasal exposure to airborne Aspergillus

4
CLASSIFICATION OF ASPERGILLOSIS

• Invasive aspergillosis
• Acute (lt1 month course)
• Subacute/chronic necrotising (1-3 months)

Airways/nasal exposure to airborne Aspergillus

• Chronic aspergillosis (gt3 months)
• Chronic cavitary pulmonary
• Aspergilloma of lung
• Chronic fibrosing pulmonary
• Chronic invasive sinusitis
• Maxillary (sinus) aspergilloma

• Persistence without disease - colonisation of the
  airways or nose/sinuses

• Allergic
• Allergic bronchopulmonary (ABPA)
• Extrinsic allergic (broncho)alveolitis (EAA)
• Asthma with fungal sensitisation
• Allergic Aspergillus sinusitis (eosinophilic
  fungal rhinosinusitis)

5
Early diagnosis of invasive aspergillosis is
important

• Treatment started lt10d gt11d
• Mortality 40 90

Von Eiff et al, Respiration 199562241-7.
6
Modalities for early diagnosis of invasive
aspergillosis

• CT scanning
• Microscopy
• Antigen (blood or respiratory fluid)
• PCR (blood or respiratory fluid)

7
Investigations for diagnosis of IPA

• Abnormal/All
• Chest X-ray 89/98 (91)
• Focal disease 58/98
  (59)
• Cavitation
  5/98 ( 5)
• Diffuse/multiple 26/98 (27)
• Chest CT scan 23/23 (100)
• Focal disease 3/23
  (13)
• Cavitation 4/23 (17)
• Diffuse/multiple 16/23
  (70)
• Bronchoalveolar lavage 36/61 (59)
• Transbronchial biopsy 4/6 (67)
• Open lung biopsy 4/8 (50)

Denning et al, J Infection 199837173-80.
8
Unequivocal Halo sign surrounding a nodule
Halo
Small vessel angioinvasion
Herbrecht, Denning et al, NEJM 2002347408-15.
9
Criteria for Halo Sign
Perimeter of ground-glass opacity surrounding a
nodular lesion
Identified early in angio-invasive aspergillosis
n
Differentiate from nodular lesions with unsharp
margination that lack a perimeter of ground-glass
gg ground-glass halo
n nodular lesion
Greene et al, ECCMID 2003
10
Criteria for Air Crescent Sign
Crescent of gas surmounting soft tissue
sequestrum within a nodular or cavitary lesion
Usually appear late in angio-invasive
aspergillosis after recovery from neutropenia
s
ac air crescent
S sequestrum
Greene et al, ECCMID 2003
11
Pulmonary nodules a useful feature if invasive
pulmonary aspergillosis

• CT features in 48 CTs of which 17 IPA
• IPA Other
• Halo 13/17 0/31
• Nodules 14/17 11/31
• Masses 6/17 2/31

Kami, Mycoses 200245287-94.
12
Pulmonary nodules a useful feature if invasive
pulmonary aspergillosis

• CT features in 235 CTs in patients with IPA
• Macronodule (gt1cm) 221 (94)
• Halo 143 (60)
• Consolidation 71 (30)
• Macro-nodule, infarct shaped 63
  (27)
• Cavitary lesion 48 (20)
• Air bronchograms 37 (16)
• Clusters of small nodules (lt1cm) 25 (11)
• Pleural effusion 25 (11)
• Air crescent sign 24 (10)
• Non-specific ground glass 21 (9)

Greene submitted, from Herbrecht N Engl J Med
2002347408.
13
Contribution of CT scans and antigen testing to
rapid diagnosis of IA
Caillot et al, J Clin Oncol 200119253
14
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
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Microscopy
Ruchel R, www.aspergillus.man.ac.uk/images
16
Sputum Cultures for Fungus
Bacteriological media inferior to fungal media
32 higher yield on fungal media
Horvath Dummer, Am J Med 1996100171-8.
17
Aspergillus workload and significance

• 3 year survey in Spanish teaching hospital
• 404 isolates from 260 patients
• 1/1000 micro samples positive
• 31/260 (12) had invasive disease
• Point score system for IA developed
• Invasive sample positive 1
• gt 2 positive samples 2
• leukaemia 2
• neutropenia 5
• corticosteroid Rx 2
• Score of 1 or 2 10.3, of 3 or 4 40, of gt5
  70

Bouza J Clin Microbiol 2005432075.
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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.
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BSMM proposed standards of care

• All bronchoscopy fluids from patients suspected
  of infection should be examined microscopically
  for hyphae and cultured on specialised media.
• All clinical isolates of Aspergillus should be
  identified to species level

Denning, Barnes and Kibbler. Lancet Infect Dis
20033230.
20

• Aspergillus Antigen Test
• Diagnosis or surveillance?
• Only blood, or BAL, CSF etc
• Best OD cut-off - 0.7
• False positives in kids / antibiotics
• False negative with antifungal
• prophylaxis
• Not as useful for non-hematology
• Not useful if pre-existing antibody

Herbrecht et al, J Clin Microbiol
2002201898-906 and others
21
Aspergillus Antigen in BAL

• 13/17 (76) in acute leukaemia with CT
  abnormality
• 5/20 (25) in suspected IFIs
• 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

Becker, Br J Haem 2003121448 Sanguinetti, JCM
2003413922 Musher, JCM 2004425517.
22
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 IA patients without haem malignancy
• Culture ve in 56/67 (84)
• Aspergillus antigen ve 27/51 (53)
• Autopsy ve for hyphae in 27/41 (66)
• Predicted mortality 48, actual 91

Meersemann et al, Am J Resp Med Crit Care
2004170621.
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CLASSIFICATION OF ASPERGILLOSIS

• Invasive aspergillosis
• Acute (lt1 month course)
• Subacute/chronic necrotising (1-3 months)

Airways/nasal exposure to airborne Aspergillus

• Chronic aspergillosis (gt3 months)
• Chronic cavitary pulmonary
• Aspergilloma of lung
• Chronic fibrosing pulmonary
• Chronic invasive sinusitis
• Maxillary (sinus) aspergilloma

• Persistence without disease - colonisation of the
  airways or nose/sinuses

• Allergic
• Allergic bronchopulmonary (ABPA)
• Extrinsic allergic (broncho)alveolitis (EAA)
• Asthma with fungal sensitisation
• Allergic Aspergillus sinusitis (eosinophilic
  fungal rhinosinusitis)

24
Simple aspergilloma
Patient RT December 2002 Cough (mild) tired
Wythenshawe Hospital
25
Aspergilloma
Severo on www.aspergillus.man.ac.uk
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Chronic Cavitary Pulmonary Aspergillosis Normal
smoking 30 year woman
Patient JA Jan 2001
27
Chronic Cavitary Pulmonary Aspergillosis
Patient JA Feb 2002
28
Chronic Cavitary Pulmonary Aspergillosis
Patient JA April 2003
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Chronic Cavitary Pulmonary Aspergillosis
Patient JA July 2003
30
Chronic cavitary pulmonary aspergillosis an
example of radiographic failure
Patient SS April 2004
Patient SS July 2004, despite receiving
itraconazole for 3 months
www.aspergillus.man.ac.uk
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Chronic pulmonary aspergillosis - serology

• All 18 patients had positive Aspergillus
  precipitins (1-4)
• All 18 patients had elevated inflammatory
  markers, CRP, PV and / or ESR
• 14 of 18 (78) had elevated total IgE (gt20), 13
  gt200 and 7 gt400
• 9 of 14 (67) had Aspergillus specific IgE (RAST)

Denning DW et al, Clin Infect Dis 2003 37S265
32
Contribution of CT scans and antibody testing to
rapid diagnosis of IA
Caillot et al, J Clin Oncol 200119253
(unpublished data)
33
Antibody diagnosis of invasive aspergillosis
In house ELISA method Definite
IA 20/31 (64.5) Probable
IA 11/67 (16.4) Possible
IA 14/55 (25.5) All
episodes 45/153 (29.4)
Herbrecht et al, J Clin Microbiol 2002201898-906
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www.aspergillus.man.ac.uk