Differential Diagnosis #3: Bilateral Upper Lung Disease

Today's Daily Diff is bilateral upper lung disease. When evaluating chest x-rays, this pattern of disease is fairly common. Having a handy list of possible diagnosis can help you narrow down possible etiologies when framed in an appropriate clinical context. One handy mnemonic to help remember this differential is CASSETTE PRR:

	Disease	Notes
C	Cystic fibrosis
A	Ankylosing spondylitis
S	Sarcoidosis
S	Silicosis
E	Eosinophilic granuloma / Langerhans cell histiocytosis	Young male smokers
T	Tuberculosis
T	Tumors (metastases)
E	Everything else

P	Pneumocystis Pneumonia (PCP)	Immunocompromised
R	Radiation fibrosis	Head and neck cancers
R	Rheumatoid lung

In general, keep in mind that the upper lung zones have increased aeration and decreased perfusion relative to the lower lung zones due to the effects of gravity.

Baca Juga