18
Diagnosis
Table 6. Histopathological Criteria for the Diagnosis of HP
(Other than "Hot-Tub Lung"
a
)
Matter Typical Sources HP "Disease"
Fibrotic HP
c
Typical histopathological
features of fibrotic HP—
1, 2, and 3 in at least one
biopsy site:
1. Chronic fibrosing
interstitial pneumonia
• Architectural
distortion, fibroblast
foci ± subpleural
honeycombing
• Fibrotic NSIP-like
d
pattern
Both of the following features
(1 and 2 from first column) in
at least one biopsy site:
1. Chronic fibrosing
interstitial pneumonia
• Architectural
distortion, fibroblast
foci ± subpleural
honeycombing
• Fibrotic NSIP-like pattern
The following features in
at least one biopsy site:
1. Chronic fibrosing
interstitial pneumonia
• Architectural
distortion, fibroblast
• Fibrotic NSIP-
like pattern
foci ± honeycombing
• Fibrotic NSIP-like
pattern
2. Airway-centered fibrosis
• ±Peribronchiolar
metaplasia
• ±Bridging fibrosis
e
2. Airway-centered fibrosis
• ±Peribronchiolar
metaplasia
• ±Bridging fibrosis
e
3. Poorly formed
nonnecrotizing
granulomas
b
±Cellular interstitial
pneumonia
±Cellular interstitial
pneumonia
±Cellular interstitial
pneumonia
±Cellular bronchiolitis
±Cellular bronchiolitis
±Cellular bronchiolitis ±Organizing pneumonia
pattern and
±Organizing pneumonia
pattern and
±Organizing pneumonia
pattern and
Absence of features in any
biopsy site to suggest an
alternative diagnosis:
• Plasma cells > lymphs
• Extensive lymphoid
hyperplasia
• Extensive well-formed
sarcoidal granulomas and/
or necrotizing granulomas
• Aspirated particulate
Absence of features in
any biopsy site to suggest
an alternative diagnosis:
• Plasma cells > lymphs
• Extensive lymphoid
hyperplasia
• Extensive well-formed
sarcoidal granulomas
and/or necrotizing
granulomas
• Aspirated particulates
Absence of features in any
biopsy site to suggest an
alternative diagnosis:
• Plasma cells > lymphs
• Extensive lymphoid
hyperplasia
• Extensive well-formed
sarcoidal granulomas
and/or necrotizing
granulomas
• Aspirated particulates
(cont'd)
