Acute Eosinophilic Pneumonia
Definition
Acute respiratory insufficiency associated with pulmonary eosinophil infiltration
Covered Separately
Diagnostic Criteria
Clinical
Acute onset of dyspnea, cough and fever
Rapid progression to respiratory insufficiency
Generally under 1-2 weeks
Presentation similar to diffuse alveolar damage / acute interstitial pneumonia
Mean age 30, usually previously healthy
Rapid response to steroids
X-ray
Bilateral diffuse opacities
Pathology
Blood eosinophils usually normal
Occasionally elevated but generally <500/mm3
Demonstration of pulmonary eosinophilia required for diagnosis with either:
Bronchoalveolar lavage (BAL) fluid shows eosinophils > lymphocytes
Usually >25%
Other cells are macrophages and neutrophils
Tissue biopsy shows prominent eosinophilic infiltrate
Biopsy is not usually necessary for diagnosis but may help rule out infection
Intra-alveolar and usually interstitial
5-25% eosinophils is consistent with diagnosis, >25% is suggestive
Eosinophils are rare in normal lung (<2%)
Changes of diffuse alveolar damage with hyaline membranes usually present
Changes of cryptogenic organizing pneumonia (BOOP) frequently present
Known causes must be ruled out
Drugs including antibiotics, non-steroidal anti-inflammatory, anti-hypertensive, heroin, cocaine
Organisms including fungi and parasites
Gerald J Berry MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting/updates: 11/20/10
Differential Diagnosis
Known causes of eosinophilic pneumonia must be ruled out
Drugs
Check history
Skin rash suggestive
Organisms
Check travel history
Check stool ova and parasites
Check serology for fungi and parasites
Culture and stain lavage and biopsy specimens
Allergic bronchopulmonary aspergillosis
Bronchiolocentric
May have necrotizing granulomatous bronchiolitis
Mucus plugs common
Culture, serology, biopsy identification
Diffuse alveolar damage pattern may be seen in acute eosinophilic pneumonia
BOOP pattern may be seen in acute eosinophilic pneumonia
Following steroid treatment, eosinophils may be harder to identify
Classification / Lists
Idiopathic Interstitial Lung Diseases
Other Diffuse Parenchymal Lung Diseases
Bibliography
Travis WD, Colby TV, Koss MN, Rosado-de-Christenson ML, Müller NL, King TE Jr. Non-neoplastic Disorders of the Lower Respiratory Tract, AFIP Atlas of Nontumor Pathology, First Series, Fascicle 2, 2002.
Tazelaar HD, Linz LJ, Colby TV, Myers JL, Limper AH. Acute eosinophilic pneumonia: histopathologic findings in nine patients. Am J Respir Crit Care Med. 1997 Jan;155(1):296-302.
Pope-Harman AL, Davis WB, Allen ED, Christoforidis AJ, Allen JN. Acute eosinophilic pneumonia. A summary of 15 cases and review of the literature. Medicine (Baltimore). 1996 Nov;75(6):334-42.
Jederlinic PJ, Sicilian L, Gaensler EA. Chronic eosinophilic pneumonia. A report of 19 cases and a review of the literature. Medicine (Baltimore). 1988 May;67(3):154-62.
Marchand E, Cordier JF. Idiopathic chronic eosinophilic pneumonia. Orphanet J Rare Dis. 2006 Apr 6;1:11..