Many past paper questions ask about the causes and differential diagnosis of " a diffuse bilateral infiltrate on CXR." There are many scenarios available. It is important to be able to generate a lot of differentials in this sort of question.
ARDS Severity | PaO2/FiO2 on PEEP of 5 | Mortality |
Mild | 200 – 300 | 27% |
Moderate | 100 – 200 | 32% |
Severe | < 100 | 45% |
In 2012, learned scholars came together and revised the old ARDS definition, making some changes to the inclusion and exclusion criteria.
An excellent article from Silvia Blanco and Antoni Torres (antimicrobe.org) actually contains a brilliant table of differentials, which is incorporated into the table below.
Vascular:
Infectious
Neoplastic
Idiopathic
|
Drug-induced
Autoimmune
Traumatic
|
Idiopathic pneumonia syndrome and ATRA syndrome(nowadays referred to as "differentiation syndrome") have been added since Question 4 from the second paper of 2015 introduced them into the list of differentials.
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