8
Figures
Figure 1. IPF Diagnosis Based Upon HRCT and Biopsy
Patterns
IPF suspected
a
Histopathology pattern
b
UIP Probable UIP
Indeterminate
for UIP or
biopsy not
performed
Alternative
diagnosis
HRCT
Pattern
UIP IPF IPF IPF Non-IPF dx
Probable UIP IPF IPF
IPF (Likely)
c
Non-IPF dx
Indeterminate IPF
IPF (Likely)
c
Indeterminate
d
Non-IPF dx
Alternative
diagnosis
IPF
(Likely)
c
Indeterminate
d
Non-IPF
diagnosis (dx)
Non-IPF dx
a
"Clinically suspected of having IPF" is defined as unexplained patterns of bilateral pulmonary fibrosis
on a chest radiograph or chest computed tomography, bibasilar inspiratory crackles, and age greater
than 60 years. Middle-aged adults >40 and <60 years old can rarely present with otherwise similar
clinical features, especially in patients with features suggesting familial pulmonary fibrosis.
b
Diagnostic confidence may need to be downgraded if histopathological assessment is based on TBLC
given the smaller biopsy size and greater potential for sampling error compared to surgical lung biopsy.
c
IPF is the likely diagnosis when any of the following features are present:
• Moderate-to-severe traction bronchiectasis/bronchiolectasis (defined as mild traction
bronchiectasis/bronchiolectasis in four or more lobes including the lingula as a lobe, or moderate
to severe traction bronchiectasis in two or more lobes) in a man over age 50 years old or in a woman
over age 60 years old.
• Extensive (>30%) reticulation on HRCT and an age >70 years.
• Increased neutrophils and/or absence of lymphocytosis in bronchoalveolar lavage fluid (BAL) fluid.
• Multidisciplinary discussion reaches a confident diagnosis of IPF.
d
Indeterminate for IPF:
• Without an adequate biopsy remains indeterminate.
• With an adequate biopsy may be reclassified to a more specific diagnosis aer multidisciplinary
discussion and/or additional consultation.
