Case and content by Lauren Brown, MD
Expert radiology interpretation by David Godwin, MD
- Use the distribution of lung disease to create a targeted differential diagnosis
35 yo woman with history of eczema and childhood asthma presents to clinic with two months of progressive dyspnea, dry cough, and daily low-grade fever, associated with myalgias, arthralgias, and non-drenching night sweats. She denies sick contacts, recent travel, or known new exposures.
Vital signs and physical examination are normal. Labs reveal WBC 15K (36% PMN, 13% L, 4% M, 46% Eos), elevated ESR/CRP, and normal BMP and LFTs.
How does the distribution of lung findings guide your differential diagnosis?
The distribution here is unusual – It is both apical AND peripheral. there is low grade consolidation (not “very” white, and could earn the descriptor ground glass opacity which applies to CXR as well as CT) concentrated in the apices and at least on the right, very peripheral. Peripheral lung processes includes embolic phenomena (metastases, septic emboli), eosinophilic pneumonias, and organizing pneumonias. Basilar predominant findings will commonly be due to blood-borne processes. This “cloak-like” distribution of peripheral AND upper-lobe predominant significantly narrows the differential, making chronic eosinophilic pneumonia most likely.
Clinical pearl: Dr. Godwin notes that this distribution was seen not uncommonly due to influenza pneumonia during the H1N1 epidemic – so influenza/viral causes should still be considered.A CT chest serves to highlight this distribution.
DIAGNOSIS AND OUTCOME:
Chronic eosinophilic pneumonia
ANA, rheumatoid factor, ANCA serologies were negative. Serum IgE level was mildly elevated, but aspergillus-specific IgE was negative. Bronchoscopy revealed marked pulmonary eosinophilia. She was treated with high dose steroids with rapid and dramatic improvement in symptoms, which were tapered off gradually over 3 months.
TAKE HOME POINTS:
- Differential diagnosis of peripheral lung processes includes embolic phenomena (septic emboli, metastases), eosinophilic pneumonias, and organizing pneumonias
- A “cloak-like” peripheral AND apical distribution strongly suggests chronic eosinophilic pneumonia